INCLUDING THE SAME

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application Serial No. 61/818,064, filed May 1, 2013, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

[0002] The commercial preparation of linear condensation polymers typically involves heating monomeric starting materials to cause progressive condensation of the polymers. In one example, this process is carried out in several stages, with the intermediate formation of low-molecular weight, low viscosity polymeric fluid by the removal of volatiles, for instance in a flasher. The low-molecular weight, low- viscosity polymeric fluid then passes through a finishing zone controlled at various vacuum and residence times and temperatures to allow the polymer to reach the desired final molecular weight and viscosity.

[0003] Polymers having a relative viscosity (RV) considerably higher than that attainable through equilibration with steam at atmospheric pressure may be desired. High RV polymers are prepared by subjecting the polymer fluid to a reduced partial pressure of steam in a finishing zone. The reduced partial pressure of steam is accomplished in finishing using an inert atmosphere or a partial vacuum. Because the polymer melt (e.g., polymer fluid) from a flasher contains considerable amounts of moisture as steam, finishing to relatively high viscosities (e.g., 50 percent) greater than viscosities attainable through steam equilibrium is an expensive and labor intensive operation in terms of inert gas consumption or equipment necessary to maintain prolonged partial vacuum. The increased time necessary to produce high viscosity polymer from the steam-laden mixed flow of steam and polymer fluid from the flasher often leads to gelled or otherwise degraded polymer. OVERVIEW

[0004] In some examples, rotatable agitators (e.g., cages or baskets) are provided within finisher vessels. Rotation of the agitators ideally reduces stagnation of a melt pool of the polymer fluid within the finisher vessel and accordingly reduces the formation of gel in the finisher vessel. Rotatable agitators include helical or spiral blades rotatable along a vessel wall. The helical or spiral blade is supported by one or more struts and an agitator ring coupled with a source of rotation, such as a screw of a screw pump. The agitator ring and the one or more struts are provided near the vessel wall and accordingly cooperate with the helical or spiral blade to wipe and mix polymer fluid along the vessel wall. Rotation of the rotatable agitator within the melt pool has been shown to intercept and dislodge gel formed along one or more of the vessel wall or the agitator ring. Stated another way, the agitator ring engages with gel along the vessel wall and dislodges the gel. The converse is also observed that gel formed along the agitator ring or struts is engaged with the inner vessel wall and dislodged. The gelled polymer breaks from the vessel wall or the agitator ring (or the struts) and is then delivered to an extruder and a pelletizer or fiber spinning system. Loose gelled polymer may cause one or more of clogs or low-quality polymer product.

[0005] The present inventors have recognized that a problem to be solved may include preventing the stagnation of polymer within a finisher vessel and reducing the incidences of dislodging of gelled polymer from within the finisher vessel. The present subject matter can provide a solution to this problem, for instance with a finisher assembly including a finisher agitator having one or more features recessed relative to an inner vessel wall while a wiping feature is maintained in close proximity to the inner vessel wall. In one example, the finisher agitator includes an agitator ring and a spiral ribbon. One or more mixing struts are coupled with the spiral ribbon and optionally coupled with the agitator ring. The spiral ribbon includes an exterior edge in close proximity to the inner vessel wall of the finisher vessel. The spiral ribbon wipes (e.g., mixes) polymer fluid along the inner vessel wall and accordingly reduces stagnation and corresponding gel formation along the associated portion of the wall. One or more of the agitator ring or the one or more mixing struts are recessed from the inner vessel wall and the exterior edge of the spiral ribbon. For instance, an agitator ring and one or more of the mixing struts are positioned within a mixing zone remote from a wiping zone adjacent to the inner vessel wall and occupied by the spiral ribbon. An elevating support raises the finisher agitator, and the agitator ring and the mixing struts are recessed from the inner vessel wall according to the elevation provided by the elevating support.

[0006] Gelled polymer gradually develops along one or more of the agitator ring, the one or more mixing struts, or the inner vessel wall opposed to the agitator ring. Because the agitator ring and the one or more mixing struts are recessed relative to the inner vessel wall, the gelled polymer is not intercepted and engaged by the opposed features. Accordingly, even where gel develops on the inner vessel wall opposed to the agitator ring, the recessed agitator ring is withdrawn and does not intercept the gel. Dislodging of the gel is thereby substantially reduced.

Conversely, gel formed along the agitator ring is recessed from the opposed portion of the inner vessel wall, does not engage with the wall, and dislodging of the gel is thereby substantially reduced. Similarly, where gel forms along the mixing struts, the recessed position of the mixing struts from the inner vessel wall (e.g., according to a widened spiral ribbon) prevents engagement of the gel with the inner vessel wall, thereby reducing dislodging of the gel along the mixing struts.

[0007] This overview is intended to provide an overview of subject matter of the present patent application. It is not intended to provide an exclusive or exhaustive explanation of the disclosure. The detailed description is included to provide further information about the present patent application. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document. [0009] FIG. 1 is a schematic diagram of one example of a continuous

polymerization system.

[0010] FIG. 2 is a schematic diagram of one example of a finisher assembly including a finisher vessel and a finisher agitator rotatable within the finisher vessel.

[0011] FIG. 3 is a detailed perspective view of the finisher agitator of FIG. 2 including an agitator ring and a plurality of mixing struts recessed from an inner vessel wall.

[0012] FIG. 4 is a top view of the finisher agitator including an expanded spiral ribbon.

[0013] FIG. 5 is a detailed perspective view of a portion of the finisher agitator within the finisher vessel.

[0014] FIG. 6 is a partial sectional view of one example of a finisher nozzle including a substantially isometric barrel and a separator helix.

[0015] FIG. 7 is a block diagram of one example of a method of using the finisher assembly including the finisher agitator of FIG. 3.

DETAILED DESCRIPTION

[0016] FIG. 1 is a schematic view of one example of a continuous polymerization system 100. As shown in FIG. 1, the continuous polymerization system 100 can provide a series of components configured to polymerize and progressively generate higher molecular weight (higher relative viscosity) polymer, for instance polyamide such as aliphatic polyamides having at least 85 percent aliphatic linkages between repeating amide units (e.g., Nylon). The polyamide can be any suitable polyamide, such as nylon 6, nylon 7, nylon 11, nylon 12, nylon 6,6, nylon 6,9; nylon 6,10, nylon 6,12, or copolymers thereof.

[0017] The continuous polymerization system 100 is configured to prepare polyamides by continuously passing an aqueous solution of a diamine-dibasic carboxylic acid salt at super- atmospheric pressure through a continuous reaction zone. At amide-forming temperatures, a diamine-dibasic carboxylic acid salt solution provided from a salt supply reservoir 102 can be passed through at least one compartment of a reaction zone 104 having one or more compartments (e.g., a reactor, flasher, finisher, or the like). The temperature-pressure conditions in one or more of these compartments prevent the formation of steam. The rate of travel of salt solution through each compartment is such that the major portion of salt is converted to polyamide. The polyamide reaction composition, while still at amide forming temperatures and now at a pressure allowing the formation of steam, then passes through at least one additional compartment of the reaction zone. In this additional compartment, water is progressively removed from the reaction composition as steam. Ultimately, the composition consists of molten polyamide, and the pressure is substantially atmospheric while a continuous polymer stream exits from the reaction zone. As shown in FIG. 1, the continuous polymer stream is delivered to one or more end-of-line components including, for instance a fiber spinning machine or pelletizer (both designated 106) that respectively spin the polymer into fibers or form the polymer into pellets.

[0018] In another example, the reaction zone 104 can be preceded by an evaporator 108. The evaporator 108 adjusts the concentration of the salt solution (through removal of water) provided from the salt supply reservoir 102 prior to polymerization in the reaction zone 104.

[0019] Returning to the discussion of the reaction zone 104 as shown in FIG. 1, the reaction zone includes a reactor 110. The salt solution is delivered to the reactor 110, and the conditions within the reactor (e.g., temperature and pressure) are maintained to convert a major portion of the salt to polymer and prevent the formation of steam. As further shown in FIG. 1, a flasher 112 can be provided downstream from the reactor 110. In the flasher 112, amidation temperatures are maintained with a gradual pressure reduction. The pressure reduction permits the separation of water from the reaction mass (e.g., water and polymer) as steam. The mixed flow of polymer and steam is fed continuously to a heated finisher 114, and polymerization is completed to a desired degree in the finisher 114. The degree of polymerization (e.g., molecular weight) is indirectly expressed in terms of polymer viscosity, which is often measured as relative viscosity or RV. Viscosity is controlled in the finishing step. At elevated temperatures, the degree of

polymerization is a function of, and limited by, the amount of water present. Accordingly, as water is removed by the finisher 114 from polymer fluid as steam, the RV is increased (e.g., the molecular weight of the polymer increases).

[0020] Polyamides having an RV considerably higher than that attainable through equilibration with steam at atmospheric pressure are desired. High RV (e.g., high molecular weight) polymers can be prepared by subjecting the mixed mass of polymer and water to a reduced partial pressure of steam in the finisher 114. The reduced partial pressure of steam is provided in finishing either by the use of an inert atmosphere or by finishing under partial vacuum (supplied in one example with a vent condenser). Finishing may require significant residence time within the finisher 114. A problem with finishing is that the increased time necessary to produce high viscosity polymer in the finisher 114 from the steam- laden mixed mass of polymer and water may lead to gelled or otherwise degraded polymer. For instance, gel typically forms along one or more parts of the finisher 114, and as the gel dislodges from the finisher 114, it may clog an exit orifice of the finisher 114 or degrade the quality of the output polymer.

[0021] FIG. 2 shows one example of a finisher assembly 200 (e.g., used as the finisher 114 in FIG. 1). As shown, the finisher assembly 200 includes a finisher nozzle 202 positioned within a finisher vessel 204. As an example, the finisher nozzle 202 as shown in FIG. 2 has a substantially constant perimeter (diameter if circular) or area extending from near an inlet orifice 206 of the finisher vessel 204 and into the interior of the finisher vessel 204. The term "substantially" as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about

99.999% or more. The walls of the nozzle 202 can be parallel to one another, such as the entire length of the walls from the inlet to the outlet of the nozzle 202, or can form an angle with respect to one another of about 0 degrees to about 20 degrees, 0 degrees to about 10 degrees, 0 to about 5.5 degrees, 0 to about 2.5 degrees, 0 to about 1.5 degrees, or about 0 degrees, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 14, 16, 18, or about 20 degrees with respect to one another. As will be described herein, the finisher nozzle 202 described and shown in FIG. 2 separates a mixed flow of polymer and steam (e.g., water) delivered from previous steps within the reaction zone 104 of the continuous polymerization system 100. The finisher nozzle 202 separates the steam from the polymer and delivers the separated steam 230 and polymer fluid 228 to the interior of finisher vessel 204 (for instance, to a melt pool 224). The finisher nozzle 202 delivers the separated polymer fluid 228 to the melt pool 224 and constrains spattering of the separated polymer fluid 228 to the melt pool 224. Stated another way, the inner vessel wall 229 of the finisher vessel 204 is isolated from spattering of the separated polymer fluid 228 (and the separated steam 230) according to the substantially constant barrel inner perimeter of the finisher nozzle 202 in

cooperation with a separator helix, described herein.

[0022] The finisher 114 can have any suitable size. For example, the finisher can have a height of about 2 to 200 m, or about 4 to 100 m, or about 5 to 50 m, or about 2 m or less, or about 3, 4, 5, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, or about 200 m or more. The finisher can have any suitable diameter. For example, the upper section of the finisher, which can have walls substantially parallel to one another, can have any suitable height, such as a height of about 1 to 100 m, or about 2 to 50 m, or about 3 to 25 m, or about 1 m or less, or about 2, 3, 4, 5, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or about 100 m or more, and can have any suitable diameter, such as a diameter (e.g. an inner or outer diameter) of about 1 to 50 m, or about 2 to 25 m, or about 3 to 15 m, or about 1 m or less, or about 2, 3, 4, 5, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45, or about 50 m or more. For example, the lower section of the finisher including the agitator assembly and having walls angling toward one another from the top section to the bottom can have any suitable height, such as about 1 to 100 m, or about 2 to 50 m, or about 3 to 25 m, or about 1 m or less, or about 2, 3, 4, 5, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or about 100 m or more, can have any suitable diameter at the upper-most portion, such as a diameter (e.g. an inner or outer diameter) of about 1 to 50 m, or about 2 to 25 m, or about 3 to 15 m, or about 1 m or less, or about 2, 3, 4, 5, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45, or about 50 m or more, and can have any suitable diameter at the lower-most portion, such as a diameter (e.g. an inner or outer diameter) of about 0.001 m to about 50 m, or about 0.01 m to about 25 m, 0.1 to about 15 m, or about 0.001 m or less, or about 0.01 m, 0.1, 0.2, 0.4, 0.6, 0.8, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, or about 50 m or more. The angle between the walls of the lower section of the finisher including the agitator assembly can be any suitable angle, such as about 20 degrees to about 120 degrees, or about 30 to about 100 degrees, or about 20 degrees or less, or about 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, or about 120 degrees or more. The height of the melt pool 224 within the finisher can be any suitable height, such as covering baffle 222 adequately to help reduce gel formation thereon, but not so high above baffle 222 that agitation fails to adequately reach the top of the melt pool 224 and forms a beachline of gel of undesirable size within the finisher (e.g., reducing the size of the beachline of gel can reduce the breaking off of gel from said beachline). In some examples, the height of the melt pool 224 within the finisher can be extending past the top of baffle 222 by about 0.1 cm to about 40 cm, or about 2 cm to about 20 cm, or about 0.1 cm or less, or about 0.5 cm, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 35, or about 40 cm or more.

[0023] As further shown in FIG. 2, the finisher assembly 200 in another example includes a heat exchanger jacket 227 positioned around the finisher vessel 204. In one example, the heat exchanger jacket 227 operates to heat the polymer fluid (for instance, the polymer fluid contained within the melt pool 224) to facilitate removal of water in the form of steam by way of a vent condenser 226. In another example, the heat exchanger jacket 227 is sized and shaped to receive a flow of heating fluid therein. In one example, the heating fluid includes, but is not limited to, a solution of diphenyl-diphenyl oxide provided as a vapor in the heat exchanger jacket 227 adjacent to the finisher vessel 204. As further shown in FIG. 2, the finisher assembly 200 further includes a barrel 213 (e.g., a barrel at an exit orifice 208). The barrel 213 and the polymer fluid delivered therethrough are optionally heated by way of the heat exchanger jacket 227. In one example, the heat exchanger jacket 227 associated with the barrel 213 is a separate jacket configured to provide a flow of liquid heating fluid therein. The liquid heating fluid includes, but is not limited to, diphenyl-diphenyl oxide in a liquid form.

[0024] Referring to FIG. 2, the finisher assembly 200 includes an exit orifice 208 at the opening of the barrel 213. The exit orifice 208 is sized and shaped to deliver the polymer fluid therethrough (for instance, to one or more end-of-line components 106, such as a fiber spinning machine or pelletizer 106 shown in FIG. 1). In one example, the exit orifice 208 and the barrel 213 include therein a screw pump 210 having a screw 212. The screw 212 of the screw pump 210 is rotated to deliver the polymer fluid from the finisher vessel 204 in a measured manner to the one or more end-of-line components 106. In another example, a downstream pump, such as a positive displacement gear pump, is interposed between the finisher assembly 200 and the end-of-line components 106. The downstream pump pumps the polymer fluid delivered from the finisher assembly 200 to one or more of these components 106.

[0025] Referring to FIG. 2, in one example, the finisher assembly 200 includes an agitator 214. As shown, the agitator 214 is coupled with the screw 212 of the screw pump 210. The agitator 214 includes one or more mixing struts 218 and one or more optional diagonal struts 219. Accordingly, rotation of the screw 212 is transmitted to the agitator 214 to agitate (mix and wipe as described herein) the polymer fluid 228 within the melt pool 224. The agitation provided by the agitator 214 consistently mixes the polymer within the melt pool 224, retards the generation of gel within the melt pool 224, and distributes heat from the heat exchanger jacket 227. The agitator can be rotated at any suitable rate, such that the shear on the inner wall of the finisher gives adequate wiping with reduced or minimized formation of gel, such as about 1 RPM to about 300 RPM, about 10 RPM to about 30 RPM, or about 16 to about 18 RPM, or about 1 RPM or less, or about 2 RPM, 4, 6, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 24, 26, 28, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 275, or about 300 RPM or more.

[0026] As further shown in FIG. 2, in one example, a vent condenser 226 extends away from the finisher vessel 204. As shown in the example, the vent condenser 226 includes a pipe elbow extending to a vent condenser mechanism at the end of the elbow. In one example, the vent condenser 226 includes a vacuum jet or vacuum generation system configured to draw in the atmosphere within the finisher vessel 204, such as a humidified (steam laden) atmosphere therein. In another example, steam is supplied to the vent condenser 226 (for instance, with a desired moisture content) to accordingly adjust the amount of moisture drawn through the vent condenser 226 from the atmosphere of the finisher vessel 204 (e.g., the separated steam 230). For instance, a flow of "kill" or supplemental steam is fed to the vent condenser mechanism of the vent condenser 226 through a supplemental steam line. The supplemental steam is decreased or increased to accordingly withdraw more or less steam with regard to the separated steam 230 within the finisher vessel 204, respectively. Stated another way, by decreasing the

supplemental steam to the vent condenser 226, a dryer stream of air at negative pressure is generated that accordingly withdraws additional stream from the finisher vessel 204. Conversely, by the increasing the supplemental steam to the vent condenser 226, a humidified stream of air is generated that withdraws less steam from the finisher vessel 204. By adjusting the infusion of supplemental steam into the vent condenser 226, the amount of separated steam 230 withdrawn from the finisher vessel 204 is tightly controlled. Accordingly, the quality of the polymer, for instance the molecular weight of the separated polymer fluid 228, is

correspondingly controlled.

[0027] Additionally, the vent condenser 226 includes a condensing system including a weir (for instance, a torus shaped weir provided on the interior perimeter of the vent condenser). The weir is filled with a flow of cooled water that overflows the sides of the weir and empties into the remainder of the vent condenser 226. The flow of cooled water (having a lower temperature relative to the separated steam 230) accordingly condenses out water from the separated steam 230 and removes moisture from the finisher vessel 204. The removal of moisture allows the separated polymer fluid 228 to increase its molecular weight with continued polymerization corresponding to an increase in the polymer relative viscosity. In another example, one or more sprays of water are provided across the vent condenser 226, for instance across the weir, to further facilitate the condensation of steam from the atmosphere within the finisher vessel 204.

[0028] FIG. 3 shows a detailed perspective view of the agitator 214 of FIG. 2. As shown in FIG. 3, the agitator 214 includes an agitator base 310 and one or more of the spiral ribbon 216, and the one or more mixing struts 218 extend from the agitator base 310, for instance upwardly, toward an agitator ring 220 (described herein). The view shown in FIG. 3 provides the finisher vessel 204 by itself (e.g., without the heat exchanger jacket 227 and other components) to better show the agitator 214 in detail. The agitator 214 can have any suitable height. For example, the agitator can have a height of about 1 m to 30 m, or about 2 to about 15 m, or about 1 m or less, or about 1 m, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 28, or about 30 m or more. The agitator 214 can have any suitable upper-most diameter, such as a diameter of about 1 to 50 m, or about 2 to 25 m, or about 3 to 15 m, or about 1 m or less, or about 2, 3, 4, 5, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45, or about 50 m or more. The agitator 214 can have any suitable lower-most diameter, such as about 0.001 m to about 50 m, or about 0.01 m to about 25 m, 0.1 to about 15 m, or about 0.001 m or less, or about 0.01 m, 0.1, 0.2, 0.4, 0.6, 0.8, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, or about 50 m or more.

[0029] The agitator 214 includes a spiral ribbon 216 extending from near the exit orifice 208 toward an upper surface of the melt pool 224 (FIG. 2). Stated another way, the spiral ribbon 216 extends from a spiral base 301 near the agitator base 310 (e.g., at the exit orifice 208 to a spiral end 303). The spiral ribbon 216 includes an exterior perimeter (an exterior edge 300) in close proximity to the inner vessel wall 229 (e.g., within about 1.3 cm of the wall, or within about 0.6 cm of the wall, such as within about 0.000,1 cm to about 1.3 cm or about 0.6 cm of the wall, such about 0.000,1 cm from the wall or less, or about 0.000,5 cm, 0.001, 0.005, 0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, or about 1.3 cm or more from the wall). The exterior edge 300 of the spiral ribbon 216 accordingly wipes polymer fluid from along the inner vessel wall 229. The spiral ribbon 216 (for instance, the upper and lower surface area of the spiral ribbon 216) mixes the polymer fluid along the inner vessel wall 229 according to the spiral configuration of the ribbon 216. When referring to "wiping" the mixing action of the spiral ribbon 216 adjacent to the inner vessel wall 229, in one example, is considered a portion of the wiping action. The rotation of the spiral ribbon 216 along the inner vessel wall 229 accordingly prevents stagnation along the inner vessel wall 229. Gel formation along the inner vessel wall 229 adjacent to the spiral ribbon 216 is thereby substantially reduced.

[0030] In another example, the agitator 214 includes one or more mixing struts 218 positioned inwardly relative to the spiral ribbon 216. For example, the spacing of the mixing struts 218 from the inner vessel wall 229 includes, but is not limited to, 5 cm or less, or about 6 cm, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 cm, or about 20 cm or more and optionally corresponds to the width of the spiral ribbon 216. The plurality of mixing struts 218 include, for instance, tapering struts extending from the exit orifice 208 to an agitator ring 220 (e.g., tapering outwardly at a similar angle to the vessel wall 229). The mixing struts 218 mix the polymer fluid within an interior portion of the melt pool 224 (for instance, remote from the inner vessel wall 229 relative to the spiral ribbon 216). Stated another way, the mixing struts 218 are positioned away from the inner vessel wall 229 and wiping of the polymer fluid along the inner vessel wall 229 is conducted by the spiral ribbon 216 while mixing of the polymer fluid within the interior of the melt pool 224 is primarily provided by the mixing struts 218 (and one or more optional diagonal struts 302 shown in FIG. 3) as well as the baffles described herein.

[0031] As further shown in FIG. 3 (and in FIG. 2), in one example, the agitator 214 includes one or more baffles 222. The baffles 222, in one example, are spiral fixtures coupled above the agitator ring 220 (described herein) and surrounded at least in part by the ring 220. The baffles 222 have a spiral shape, for example similar to an angled boomerang. The baffles 222 are perforated between upper and lower surfaces to allow the flow of polymer fluid therethrough (for instance, toward the exit orifice 208). In another example, the baffles 222 include an upper baffle and a lower baffle (the lower baffle being concealed at least partially by the agitator ring 220 shown in FIG. 2) that provide downward and upward movement to the polymer fluid, respectively, to vertically mix the polymer fluid within the finisher vessel 204.

[0032] Referring to FIG. 3, the various features of the agitator 214 (e.g., the mixing struts 218, spiral ribbon 216, and the baffles 222 also shown in FIG. 2) cooperate to mix and thereby reduce the stagnation of the polymer fluid within the finisher vessel 204 as water in the form of steam is gradually removed (e.g., by way of the vent condenser 226) to facilitate the increase of relative viscosity

corresponding to the generation of higher molecular weight polymer. The configuration of the agitator 214 shown in FIGS. 2 and 3, as described herein, substantially reduces the formation of gel within the finisher assembly 200 while at the same time reducing the dislodging of gel formed within the finisher vessel 204. By increasing mixing and decreasing stagnation, the baffles can increase the rate of water removal from the reaction mixture, and as compared to an agitator not having the baffles, the baffles can result in about 0.001% to about 10% by mass greater water removal per hour, or about 0.001% or less, or about 0.005, 0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, or about 10% by mass greater water removal per hour.

[0033] Referring now to FIGS. 3 and 4 (also shown in FIG. 2), one example of an agitator ring 220 of the agitator 214 is shown. The agitator ring 220 is coupled with one or more of the mixing struts 218 (and indirectly with the spiral ribbon 216) to provide support to the mixing struts 218, the spiral ribbon 216, and the baffles 222. The agitator ring 220 accordingly maintains these components in the arrangement shown in FIGS. 3 and 4. Additionally, the agitator ring 220 provides another feature to the agitator 214 configured to mix the polymer fluid and accordingly reduce stagnation and gel formation. For instance, as shown in FIG. 3, the agitator ring 220 includes one or more mixing ridges 314 along a ring exterior edge 316. The one or more mixing ridges 314 mix polymer fluid adjacent to the agitator ring 220 and reduce stagnation along the ring 220 (reducing the formation of gel along the ring). In another example, one or more notches 318 are provided in the agitator ring 220 adjacent to one or more of the mixing ridges 314. In one example, the notches 318 are provided on a trailing side of the respective mixing ridges 314 (e.g., the notches are on a trailing or downstream side of the ridges with rotation of the agitator 214 in a corresponding first direction). By increasing mixing and decreasing stagnation, the mixing ridges and notches can increase the rate of water removal from the reaction mixture, and as compared to an agitator not having the mixing ridges and notches, the mixing ridges and notches can result in about 0.001% to about 10% by mass greater water removal per hour, or about 0.001% or less, or about 0.005, 0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, or about 10% by mass greater water removal per hour.

[0034] In the example shown in FIG. 3 (and shown in the top view of FIG. 4), the agitator ring 220 is positioned remotely relative to the inner vessel wall 229.

Accordingly, as the agitator 214 rotates within the finisher assembly 200, for instance within the melt pool 224, the agitator ring 220 is spaced away from the inner vessel wall 229 by a gap or clearance. The spacing of the agitator ring 220 from the inner vessel wall 229 can be, but is not limited to, 5 cm or less, or about 6 cm, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 cm, or about 20 cm or more. In a similar manner, and as previously described herein, the one or more mixing struts 218 provided are remote from the inner vessel wall 229 (e.g., spaced by a gap or clearance corresponding, in one example, to a width of the spiral ribbon 216). The mixing struts 218 are shown in FIGS. 3 and 4 positioned remotely relative to the inner vessel wall 229. As shown, the exterior edge 300 of the spiral ribbon 216 is positioned in close proximity to the inner vessel wall 229 while the mixing struts 218 and the agitator ring 220 are recessed relatively from the wall (compared to the exterior edge 300).

[0035] The spiral ribbon 216 is configured to wipe (e.g., mechanically wipe and mix) along the inner vessel wall 229 and substantially reduce stagnation of the polymer fluid along the wall. In one example, the region along the inner vessel wall 229 wiped by the spiral ribbon is a wiping zone. In contrast, the agitator ring 220 and the mixing struts 218 (remotely positioned from the inner vessel wall 229 mix the polymer fluid located inwardly relative to both the wall 229) and the exterior edge 300 of the spiral ribbon 216 (e.g., within a mixing zone). [0036] As shown in FIG. 3, in one example, the mixing struts 218 and the spiral ribbon 216 extend from an agitator base 310. As previously described, the agitator base 310 serves as a center point or interface for the mixing struts 218 and the spiral ribbon 216. The agitator base 310, in another example, is elevated from a position at the exit orifice 208 of the finisher vessel 204 by an elevating support 304.

Referring again to FIG. 3, the elevating support 304 includes a pump interface 306 and an agitator interface 308. The pump interface 306 allows for coupling of the elevating support 304 with the screw 212 of the screw pump 210 (shown in FIG. 2). Conversely, the agitator interface 308 allows for coupling of the elevating support 304 with the remainder of the agitator 214, for instance, the agitator base 310.

[0037] As shown in FIG. 3, the elevating support 304 positions and suspends the agitator 214 within the finisher vessel 204. As previously described, the one or more mixing struts 218 extend from the agitator base 310, for instance, toward the agitator ring 220. As shown in the example, the one or more mixing struts 218 are angled at a similar angle relative to the inner vessel wall 229 corresponding to the tapered portion of the wall of the finisher vessel 204. The elevating support 304 when coupled (or incorporated) with the agitator base 310 elevates the agitator 214 including the mixing struts 218. Accordingly, as shown in FIG. 3, the elevating support 304 positions the mixing struts 218 while at the same time the mixing struts 218 are moved inwardly because of the elevation change relative to the inner vessel wall 229. For instance, with removal of the elevating support 304, the agitator 214 is correspondingly positioned nearer the exit orifice 208, and the mixing struts 218 are in close proximity to the inner vessel wall 229. Stated another way, the mixing struts 218 are recessed or spaced from the inner vessel wall 229 according to the relative position provided by the elevating support 304.

[0038] In a similar manner, the elevating support 304 also positions and supports the remainder of the agitator 214 including the agitator ring 220. As shown in FIG. 3 and as previously described herein, the agitator ring 220 is recessed relative to the opposed portion of the inner vessel wall 229 adjacent to the ring. Because the elevating support 304 positions the agitator 214 within the finisher vessel 204, the agitator ring 220 is accordingly recessed relative to the opposed portion of the inner vessel wall 229. Stated another way, because the finisher vessel 204 is tapered toward the exit orifice 208, the ring is recessed from the inner vessel wall 229 by raising the agitator ring 220 toward an outwardly tapered portion of the vessel 204. Accordingly, the elevating support 304 recesses each of the mixing struts 218 and the agitator ring 220 from the inner vessel wall 229 by elevating the agitator 214 relative to the finisher vessel 204.

[0039] In one example, the elevating support 304 is integral to the agitator base 310. For instance, the agitator 214 is provided with the elevating support 304 as part of the agitator base 310. In another example, the elevating support 304 is an aftermarket feature coupled to the agitator base 310 and installed during retrofitting. Accordingly, by providing the elevating support 304, the one or more mixing struts 218 and the agitator ring 220 are lifted and thereby recessed relative to the inner vessel wall 229 (e.g., out of the wiping zone). As will be described herein, recessing of one or more of the agitator ring 220 or the one or more mixing struts 218 positions each of the these features remotely relative to polymer gel formed on portions of the inner vessel wall 229 opposed to either the ring 220 or the struts 218.

[0040] Referring to FIG. 4, a top view of the finisher assembly 200 including the agitator 214 within the finisher vessel 204 is provided. As previously described, the agitator 214 is rotatably coupled within the finisher vessel 204. As also described, the one or more mixing struts 218 extend from the agitator base 310, for instance toward the agitator ring 220. The spiral ribbon 216 is coupled with and extends around one or more of the mixing struts 218. Accordingly, with rotation of the agitator base 310, the agitator 214 (e.g., including the spiral ribbon 216, the mixing struts 218, and the agitator ring 220) is rotated within the finisher vessel 204. As previously described, the rotation of these elements mixes the polymer fluid (e.g., the polymer of the melt pool) within the finisher vessel 204 and reduces stagnation of polymer fluid (and corresponding gel formation) within the finisher vessel 204.

[0041] Referring to FIG. 4, the spiral ribbon 216 is shown in a two-part configuration. As previously described, in one example the agitator base 310 is elevated within the finisher vessel 204, for instance with elevating supporting 304 (shown in FIG. 3). The elevation provided by the elevating support 304 correspondingly recesses the one or more mixing struts 218 and the agitator ring 220 from the inner vessel wall 229 (for instance, portions of the inner vessel wall 229 opposed to each of these features). Elevation of the agitator 214 also recesses the spiral ribbon 216 relative to the inner vessel wall 229. In one example, a supplemental ribbon 400 is coupled along an interior ribbon 402 (e.g., the original spiral ribbon in a retrofitted or modified finisher assembly). For instance, as shown in FIG. 4, the supplemental ribbon 402 is coupled along an exterior portion of the interior ribbon 400. Accordingly, the exterior edge 300 shown in FIG. 3 corresponds to the exterior edge of the supplemental ribbon 402. Similarly, an interior edge 312 shown in FIG. 3 corresponds to the interior edge 312 of the interior ribbon 400.

[0042] In one example, the elevating support 304 raises the agitator 214 approximately 10 cm, as shown in FIG. 4. The supplemental ribbon 402 provides an increased surface area (e.g., an increase in width) relative to the interior ribbon 400 of about 5.8 cm. That is to say, the width of a composite ribbon (interior and supplemental ribbons 402, 400) interior is increased about 5.8 cm with the supplemental ribbon 402. Accordingly, with this arrangement (referring now to FIG. 3), the exterior edge 300 of a composite spiral ribbon 216 is positioned in close proximity to the inner vessel wall 229 even while the plurality of mixing struts 218 and the agitator ring 220 are recessed relative to the corresponding opposed portions of the inner vessel wall 229 with the elevating support 304.

[0043] In another example, the spiral ribbon 216 is unitary. Stated another way, the spiral ribbon is provided with the width shown in FIG. 4 corresponding to the width of the interior and supplemental ribbons 402, 400. For instance, where the elevating support 304 is incorporated into the agitator base 310, the spiral ribbon 216 optionally includes a wider unitary ribbon that allows for recessing of the mixing struts 218 while maintaining the exterior edge 300 in close proximity to the inner vessel wall 229. That is to say, the spiral ribbon 216 extends from the interior edge 312 optionally coupled to the mixing struts 218 to the exterior edge 300 as a unitary component (or a plurality of components as described above).

[0044] Referring to FIG. 3, in another example, a scraping blade 404 is provided with the agitator 214. In one example, the scraping blade 404 is coupled with the agitator ring 220. The scraping blade 404 extends from the agitator ring 220 toward the inner vessel wall 229. For instance, the scraping blade 404 is configured to provide a wiping function in a similar fashion to the spiral ribbon 216 as described herein. Referring to FIG. 4, the scraping blade 404 is shown in the top view in close proximity to the inner vessel wall 229. The scraping blade 404 thereby provides mixing (including wiping and mixing based on turbulence generated by the blade) along the inner vessel wall 229 immediately adjacent to the agitator ring 220.

Accordingly, stagnation in the melt pool 224 is substantially reduced from the area of the agitator ring 220 upwardly toward a beach line of the pool. That is to say, the scraping blade 404 provides wiping along the portion of the inner vessel 229 opposed to the blade and is thereby positioned within the wiping zone similar to the wiping zone of the spiral ribbon 216. By increasing mixing and decreasing stagnation, the scraping blade can increase the rate of water removal from the reaction mixture, and as compared to an agitator not having the scraping blade, the scraping blade can result in about 0.001% to about 10% by mass greater water removal per hour, or about 0.001% or less, or about 0.005, 0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, or about 10% by mass greater water removal per hour.

[0045] Referring now to FIG. 5, a portion of the finisher assembly 200 is provided. As shown, the agitator 214 is positioned within the finisher vessel 204. As previously described and shown again in FIG. 5, the agitator 214 includes an elevating support 304 coupled with or incorporated into an agitator base 310. One or more mixing struts 218 extend from the agitator base 310 toward the agitator ring 220. The spiral ribbon 216 extends around the mixing struts 218, for instance as shown in FIG. 3, an interior edge 312 of the spiral ribbon 216 is coupled at points along the mixing struts 218. The exterior edge 300 of the spiral ribbon 216 is in close proximity to the inner vessel wall 229.

[0046] As shown in FIG. 5 the spiral ribbon 216 is positioned in close proximity to the inner vessel wall 229. A wiping zone (shown in FIG. 5) is shown by way of a broken line corresponding to that portion of the spiral ribbon 216 in close proximity to the inner vessel wall 229. The spiral ribbon 216 is configured to wipe (e.g., mechanically engage polymer fluid within the melt pool and generate turbulence along the inner vessel wall 229) to substantially reduce stagnation of the polymer fluid along the inner vessel wall 229. As further shown in FIG. 5, a mixing zone is shown positioned inwardly relative to the wiping zone. The mixing struts 218 and the agitator ring 220 are positioned within the mixing zone and mix polymer fluid within the mixing zone.

[0047] As previously described, by recessing the one or more mixing struts 218 as well as the agitator ring 220 from the inner vessel wall 229, interaction of these features with formed gel along the inner vessel wall 229 is substantially reduced. For instance, as shown in FIG. 5, polymer gel 500 can form along a portion of the inner vessel wall 229. Because the agitator ring 220 is recessed relative to the inner vessel wall 229 (optionally as a function of the elevating support 304), in various embodiments the agitator ring 220 does not physically engage with the polymer gel 500 and dislodge the gel during operation of the finisher assembly 200. Instead, the majority of the polymer gel 500 is retained along the inner vessel wall even while components of the agitator 214, such as the spiral ribbon 216 and the scraping blade 404, wipe the portions of the inner vessel wall 229 opposed to those components. Because the agitator ring 220 is recessed relative to the inner vessel wall 229, each of these features may pass over and not contact the polymer gel 500 formed along the inner vessel wall. Accordingly, even with formation of some polymer gel at stagnant locations along the inner vessel wall 229 (e.g., opposed to the agitator ring 220), the finisher assembly 200 may continue operation without dislodging of the polymer gel and thereby avoid the drawbacks of dislodged gel (e.g., clogging and incorporation of the gel polymer into otherwise higher grade polymer generated within the finisher assembly 200).

[0048] Similar to the gel 500 shown in FIG. 5, gel 502 formed along the mixing struts 218 does not interact with the inner vessel wall 229 (except in the most extreme circumstances where the polymer gel 502 is allowed to accrue over a significant amount of time, for instance longer than 91 days or the like). As shown in FIG. 5, the accrued polymer gel 502 on the recessed mixing struts 218 is similarly recessed from the inner vessel wall 229. Accordingly, interaction between the inner vessel wall 229 and the polymer gel 502 (engagement and dislodging during rotation of the agitator 214) is substantially avoided.

[0049] As shown in FIG. 5 and described herein, any gel 500 or 502 provided on one or more of the components of the finisher assembly 200, whether the inner vessel wall 229 or a component of the agitator 214 such as the mixing struts 218, is isolated from an opposed portion of the finisher assembly 200. That is to say, polymer gel 500 formed along the inner vessel wall 229 is isolated from interception by the rotating agitator ring 220. Similarly, polymer gel 502 formed along the mixing struts 218 (or the agitator ring 220) is isolated from the otherwise static inner vessel wall 229. Accordingly, gel 500, 502 remains bonded onto respective components (e.g., the wall 229, agitator ring 220 or mixing struts 218) without dislodging.

[0050] Referring now to FIG. 6, another example of a component of the finisher assembly 200 is shown; the component is an example of a finisher nozzle 202 that provides the inflow of polymer fluid 228 to the finisher assembly 200. FIG. 6 is a partial cross section of the finisher nozzle 202. A barrel 603 of the nozzle 202 is sectioned along its midline while a separator helix therein 606 is shown in a side view. The cylindrical barrel 603 extends from an inlet orifice 600 to an outlet orifice 602. The barrel 603 has a barrel inner perimeter 604 circumscribing a lumen extending therethrough. As shown in FIG. 6, the barrel 603 has a substantially constant inner area 607 (the cross sectional area of the barrel measured

perpendicular to the helix axis 608, described below) between the inlet orifice 600 and the outlet orifice 602. That is to say, the barrel 603 is substantially isometric between the inlet and outlet orifices 600, 602. In one example, a portion of the finisher nozzle 202, for instance adjacent to the outlet orifice 602 or adjacent to the inlet orifice 600, may have a short tapered perimeter according to the needs of the particular finisher nozzle 202 for use with the finisher assembly 200 shown in FIG. 2. As shown in FIG. 6, the barrel inner perimeter 604 and the inner area 607 are substantially constant over the length corresponding to the separator helix 606, described further herein. [0051] As will be described herein, the isometric barrel 603 (e.g., having a substantially constant barrel inner perimeter 604 and a substantially constant inner area 607) cooperates with a separator helix 606 (shown herein) to separate the mixed flow of polymer fluid and steam and accordingly deliver separated polymer fluid 228 and separated steam 230 to the finisher vessel 204. The finisher nozzle 202 substantially prevents the re-entrainment of polymer with the separated steam 230 to substantially reduce spattering of the separated polymer 228 otherwise re- entrained with the separated steam 230 along the inner vessel wall 229 of the finisher vessel 204 shown in FIG. 2, as described herein.

[0052] In FIG. 6, the separator helix 606 is shown extending through at least a portion of the barrel 603. As shown, the separator helix 606 includes a plurality of helical segments 610 coupled in an end-to-end series as shown. In the example shown in FIG. 6, a separator base plate 612 having a substantially straight configuration is coupled with the adjacent helical segment 610. The remainder of the helical segments 610 extending toward the outlet orifice 602 have a twisted configuration and cooperate to separate the polymer fluid 228 from the steam 230 to deliver the separated polymer fluid 228 to the finisher vessel 204, for instance without spattering the inner vessel wall 229.

[0053] In one example, each of the helical segments 610 include first and second ends 614, 616. Each of the helical segments extends in a helical fashion (e.g., twists) from the first end 614 to the second end 616. As previously described, the separator helix 606 and its segments 610 are shown in a side view (not sectioned); accordingly, the first end 614 is shown substantially perpendicular to the page while the second end 616 is parallel to the page. The remainder of each of the segments 610 accordingly twists between first end 614 and second end 616. In the example shown in FIG. 6, each of the helical segments 610 twists approximately 90 degrees from the first end 614 to the adjacent second end 616. For instance, the exterior edge 605 along an upper portion (as shown in FIG. 6) of the helical segments 610 gradually extends into the page as the exterior edge 605 extends toward the first end 614 from the second end 616. Conversely, the exterior edge 605 along a lower portion (as shown in FIG. 6) of the helical segment 610 gradually extends out of the page as the edge extends from the second end 616 to the first end 614.

[0054] In another example, adjacent helical segments 610, for instance the helical segment 610 next in line toward the outlet orifice 602 when beginning at the inlet orifice 600, includes a first end 614 approximately 90 degrees out of phase with the adjacent second end 616 of the preceding helical segment 610. Accordingly, the separator helix 606 in the example shown in FIG. 6 provides a broken (non- continuous) chain of helical segments 610 each providing a twisted helical surface (e.g., twisting in the same direction clockwise or counterclockwise) that are mated at their ends at approximately 90 degrees relative to one another. That is to say, the second end 616 of a helical segment 610 is approximately 90 degrees out of phase to the first end 614 of a proceeding helical segment 610. In one example, the helical segments 610 are mated with one another by one or more mechanisms including, but not limited to, a weld, mechanical interfitting (such as one element having a lock features and another element having a corresponding key feature), or the like.

[0055] As shown in FIG. 6, in one example, the separator helix 606 is coupled at one or more segment anchors 618 to thereby space the remainder of the separator helix 606 (e.g., such as an exterior edge 605 of each of the segments 610 extending along the perimeter 604) from the barrel inner perimeter 604. The separation (such as a clearance or separator gap 620), between each of the helical segments 610 and the barrel inner perimeter 604 cooperates to provide a path for separated steam (such as the separated steam 230 shown in FIG. 2) to travel isolated relative to the separated polymer 228 delivered along a helix axis 608. In the example shown in FIG. 6, each of the helical segments 610 is coupled with the barrel inner perimeter 604 by separate segment anchors 618 at the second ends 616 (or optionally at the first end 614 or an intermediate portion of the segments 610). The path for the separated steam 230 extends through the separator gap 620 provided between the inner perimeter 604 and the exterior edges 605 according to the spacing (or clearance) provided by the segment anchors 618.

[0056] Each of the helical segments 610 are, in one example, respectively coupled with the barrel inner perimeter 604 (for instance, with the segment anchors 618). The segment anchors 618 cooperate to affix each of the helical segments 610 in place within the barrel 603. Accordingly, during servicing of the finisher nozzle 202 (e.g., during removal of the finisher nozzle 202 for cleaning or for inline cleaning of the finisher nozzle 202), heating of the nozzle 202 including the separator helix 606 does not warp the separator helix 606 and maintains the plurality of helical segments 610 in the orientation shown in FIG. 6. That is to say, the segment anchors 618 (and optionally a plate anchor 622) cooperate to anchor each of the helical segments 610 (and optionally the separator base plate 612) within the barrel 603. Stated another way, warping of the separator helix 606 is reduced or prevented by anchoring each of the helical segments 610. Each of the helical segments 610 of the separator helix 606 can be firmly anchored in place.

Accordingly, as the separator nozzle 202 including the separator helix 606 is heated during cleaning (and cooled afterwards), the separator helix 606 does not warp within the barrel 603. The arrangement of the separator helix 606, for instance with the separator gap 620, is thereby maintained during the operational lifetime of the finisher nozzle 202 including during and after cleaning operations.

[0057] In operation, a mixed flow of polymer fluid and steam is delivered through the inlet orifice 600 shown in FIG. 6 (e.g., from a preceding portion of the continuous polymerization system 100 shown in FIG. 1). For instance, the mixed flow of polymer fluid and steam is delivered from the flasher 112 to the schematic finisher 114 shown in FIG. 1. As shown in FIG. 2, the finisher nozzle 202 delivers the mixed flow of fluid into the finisher vessel 204 and separates the mixed flow into separated steam 230 and separated polymer fluid 228.

[0058] The mixed flow of polymer fluid is delivered into the inlet orifice 600 of the barrel 603 of the finisher nozzle 202. The mixed flow is delivered along the separator base plate 612 and onto the separator helix 606. Because of the isometric barrel 603 (e.g., substantially constant barrel inner perimeter 604 and substantially constant inner area 607), as the mixed flow of polymer and steam is delivered through the barrel 603, its velocity is substantially maintained or increased as the fluid is delivered toward the outlet orifice 602. In one example, the inner perimeter 604, for instance a diameter of the inner perimeter, is decreased relative to previous finisher nozzles to further increase shear within the mixed flow of polymer and steam. In one example, the finisher nozzle 202 has an inner diameter of 12.7 cm compared to a 17.8 cm diameter of a previous tapered nozzle.

[0059] As the mixed flow moves along the separator helix 606, the mixed flow engages the series of helical segments 610. As previously described, each of the helical segments 610 has a twisted shape (including, for instance, a 90 degree twist). Each of the helical segments 610, in yet another example, are twisted in the same direction (e.g., clockwise or counterclockwise). As the mixed flow of polymer fluid flows along and follows each of the helical segments 610, the velocity of the fluid is maintained by the isometric barrel 603. That is to say, because the barrel 603 is isometric (e.g., does not include an expanding taper from the inlet to the outlet), velocity of the mixed flow as it is delivered into the barrel 603 is maintained or increased as opposed to decreasing with an expanding tapered nozzle. The helical segments 610 divide or separate the mixed flow, for instance by allowing the polymer fluid to travel along the helix axis 608, while the less dense steam 230 moves to the outlying portions of the helical segments 610 and into the separator gap 620 according to its maintained velocity. The denser polymer fluid 228 maintains a substantially linear flow along the helix axis 608 and is thereby separated from the steam 230. Accordingly, at the outlet orifice 602 of the finisher nozzle 202, the polymer fluid 228 is delivered primarily along the helix axis 608, and the separated steam 230 is delivered primarily along the barrel inner perimeter 604 (and downwardly directed parallel to the helix axis 608) into the finisher vessel 204 as shown in FIG. 2.

[0060] Further, the separation provided by the separator helix 606 in combination with the isometric barrel 603 (as well as the separator gap 620 maintained therebetween) guides the separated steam 230 into the separator gap 620 and accordingly substantially reduces re-entrainment of the polymer fluid traveling along the segments 610 into the steam. Stated another way, the steam maintains its velocity by way of the substantially isometric barrel 603 (e.g., having constant perimeter and area) and accordingly is guided into and maintained within the separator gap 620 (and along inner perimeter 604) away from the guided polymer fluid 228. Separation of the steam 230 and the polymer fluid 228 is thereby maintained through passage within the nozzle 202 and delivery to the finisher vessel 204.

[0061] Moreover, with the arrangement shown in FIG. 6, as the separated polymer fluid 228 and the separated steam 230 are guided and delivered into the finisher vessel 204 by the isometric barrel 603 (e.g., with the substantially constant barrel inner perimeter 604 and inner area 607), any spattering of the polymer fluid 228 is substantially constrained to the melt pool 224. As discussed above, the inner vessel wall 229 is isolated from spattering of the separated polymer 228. Steam is less dense and disperses more easily than the polymer toward the inner vessel wall 229. Accordingly, outward spattering toward the wall 229 is reduced by preventing re-entrainment of the polymer within the steam. Further, the flow of the separated steam 230 is directed substantially along the helix axis 608 and toward the melt pool 224. Lateral velocity components of the separated steam 230 moving through the finisher nozzle 202 are reduced (relative to an expanding nozzle) by the isometric barrel 603 (e.g., having a substantially constant barrel inner perimeter 604 and inner area 607). Accordingly, spattering along the inner vessel wall 229 by way of steam 230 with re-entrained polymer 228 is substantially reduced. Instead, the separated polymer 228 (as well as the separated steam 230) is directed toward the melt pool 224 (see FIG. 2) by the finisher nozzle 202, and spattering from the finishing nozzle 202 is similarly directed into the melt pool 224.

[0062] FIG. 7 shows a block diagram for a method 700 for using a polymer finisher assembly, for instance the finisher assembly 200 shown in FIG. 2 including a finisher agitator 214. In describing the method 700, reference is made to one or more components, features, functions, steps, or the like described herein. Where convenient, reference is made to the components, features, steps, functions, or the like with reference numerals. The reference numerals provided are exemplary and are not exclusive. For instance, the features, components, functions, steps, or the like described in the method 700 include, but are not limited to, the corresponding numbered elements, the corresponding features described herein (both numbered and unnumbered), and their equivalents. [0063] At 702, the method 700 includes agitating a polymer fluid within a melt pool 224 (see FIG. 2) with a finisher agitator such as the agitator 214 shown in FIGS. 2, 3, and 4. In one example, agitating the polymer fluid 228 includes at 704 wiping the polymer fluid along an inner vessel wall 229 (see FIG. 5) with the spiral ribbon 216 of the finisher agitator 214. In another example, agitating the polymer fluid within the melt pool 224 further includes, at 706, mixing the polymer fluid with one or more of an agitator ring 220 or one or more mixing struts 218 coupled with the spiral ribbon 216. The agitator ring and the one or more mixing struts are spaced from the inner vessel wall 229, as previously described herein.

[0064] At 708, the method 700 further includes isolating the agitator ring 220 from gel formed along the inner vessel wall 229 or isolating the inner vessel wall 229 from gel formed on the one or more mixing struts 218 according to the spacing of the agitator ring 220 and the one or more mixing struts from the inner vessel wall. In another example, the agitator ring 220 or the one or more mixing struts 218 are spaced from the inner vessel wall 229 by elevating the agitator 214 within the finisher vessel 204. As shown, for instance in FIG. 3 and further described herein, an elevating support 304 raises the remainder of the agitator 214 within the finisher vessel 204 and accordingly moves the mixing struts 218 and the agitator ring 220 inwardly relative to the corresponding opposed portions of the inner vessel wall 229.

[0065] Several options for the method 700 follow. In one example, wiping the polymer fluid includes mechanically engaging the polymer fluid with the spiral ribbon, for instance by mechanically engaging an exterior edge 300 along the polymer fluid adjacent to the inner vessel wall 229. In another example, wiping includes generating turbulence with the rotating movement of the spiral ribbon 216 along the inner vessel wall 229. Wiping adjacent to the inner vessel wall 229 (e.g., within the wiping zone shown in FIG. 5) accordingly prevents stagnation of polymer along this portion of the inner vessel wall 229.

[0066] In another example, isolating one or more of the agitator ring 220 or the one or more mixing struts 218 from gel includes spacing the agitator ring 220 and the one or more mixing struts 218 away from the inner vessel wall 229 relative to an exterior edge 300 of the spiral ribbon 216 in close proximity to the inner vessel wall 229. That is to say, the mixing struts 218 and the agitator ring 220 are recessed relative to the opposed portions of the inner vessel wall 229 compared to the close proximity of the exterior edge 300 of the spiral ribbon 216 with the inner vessel wall 229. For instance, as stated herein, the exterior edge 300 of the spiral ribbon 216 is positioned within the wiping zone and at least the agitator ring 220 and the one or more mixing struts 218 are positioned remotely relative to this close proximity from the inner vessel wall 229. In various examples, the spacing of the agitator ring 220 from the inner vessel wall 229 includes, but is not limited to, 5 cm or less, or about 6 cm, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 cm, or about 20 cm or more. In another example, the method 700 includes retaining gel, for instance gel 500 formed along one or more of the inner vessel wall 229, the agitator ring 220 or the one or more mixing struts 218 (e.g., gel 502) during agitation based on spacing of the agitator ring 220 and the one or more mixing struts 218 recessed from the inner vessel wall 229. That is to say, any gel formed along the agitator ring 220 and the one or more mixing struts 218 is recessed from the inner vessel wall 229.

Accordingly, with rotation of the agitator 214, this gel 502 fails to engage with the inner vessel wall 229 and is retained along these features without dislodging.

[0067] Mixing the polymer fluid with the agitator ring 220 includes, in one example, mixing the polymer fluid with the agitator ring 220 having one or more mixing ridges 314 along a ring exterior edge 316. For instance, the one or more mixing ridges 314 are provided at one or a plurality of locations along the ring exterior edge 316. In another example, mixing the polymer fluid with the agitator ring 220 includes mixing the polymer fluid with the agitator ring 220 having one or more notches 318 on a trailing side (relative to the direction of rotation) of one or more of the mixing ridges 314.

[0068] In still another example, the method 700 further includes separating a mixed flow of steam and polymer fluid with a separator helix, such as the separator helix 606 shown in FIG. 6. As shown, the separator helix 606 is positioned within a barrel 603 of a finisher nozzle 202. The finisher nozzle 202 is configured to deliver the polymer fluid 228 to the finisher vessel 204 and substantially prevent the re- entrainment of the polymer fluid 228 within separated steam 230 as described herein. In another example, the method 700 includes delivering the separated polymer fluid 228 to the melt pool 224 of polymer fluid with the finisher nozzle 202 as shown, for instance, in FIG. 2. The method 700 further includes isolating the inner vessel wall 229 (above a beach line of the melt pool 224) from spattering of the separated polymer fluid 228 according to the barrel 603 having one or more of a substantially constant inner perimeter or a substantially constant area. For instance, where the barrel 603 is substantially isometric from the inlet orifice 600 toward the outlet orifice 602, each of the separated polymer fluid 228 and the separated steam 230 are directed downwardly into the melt pool 224. Additionally, and as described herein, a separator helix 606 guides the separated steam 230 (for instance, to a separator gap 620) to segregate the separated steam 230 from the separated polymer fluid 228 otherwise delivered along the helix axis 608. In one example, the isometric barrel 603 allows for the maintenance of velocity of the mixed flow of polymer and steam within the finisher nozzle 202 and accordingly facilitates the separation of the steam 230 from the polymer fluid 228. For instance, the steam 230 spins outwardly along the helical segments 610 toward the separator gap 620 and accordingly (at least in part due to the velocity of the steam) remains separated from the more centrally flowing polymer fluid.

Example 1 - Finisher Assembly with Mixing Struts Adjacent to Inner Vessel Wall.

[0069] In a continuous nylon 6,6 manufacturing process, adipic acid and hexamethylenediamine are combined in a salt strike in an approximately equimolar ratio in water to form an aqueous mixture containing nylon 6,6 salt having about 50 wt water. The aqueous salt is transferred to an evaporator at about 105 L/min. The evaporator heats the aqueous salt to about 125-135 °C (130 °C) and removes water from the heated aqueous salt, bringing the water concentration to about 30 wt . The evaporated salt mixture is transferred to a reactor at about 75 L/min. The reactor brings the temperature of the evaporated salt mixture to about 218-250 °C (235 °C), allowing the reactor to further remove water from the heated evaporated salt mixture, bringing the water concentration to about 10 wt , and causing the salt to further polymerize. The reacted mixture is transferred to a flasher at about 60 L/min. The flasher heats the reacted mixture to about 270-290 °C (280 °C), allowing the flasher to further remove water from the reacted mixture, bringing the water concentration to about 0.5 wt , and causing the reacted mixture to further polymerize. The flashed mixture is transferred to a finisher at about 54 L/min. The finisher subjects the polymeric mixture to a vacuum to further remove water, bringing the water concentration to about 0.1 wt , such that the polyamide achieves a suitable final range of degree of polymerization before transferring the finished polymeric mixture to an extruder and a pelletizer.

[0070] The finisher has an approximately cylindrical upper portion that is 20 meters tall and an inner diameter of about 7 meters. The finisher has an

approximately conical lower portion that is about 5 meters tall, an upper diameter of about 7 meters, and a lower diameter of about 0.5 m, with the side walls forming an angle of 70 degrees with one another. The finisher assembly includes a finisher agitator with mixing struts positioned adjacent to the inner vessel wall of a finisher vessel, such that the mixing struts are about 3.8 cm to about 5 cm away from the inner wall of the vessel. Rotation of the mixing struts and the spiral ribbon of the finisher agitator mechanically engages the polymer fluid along an inner vessel wall within a melt pool. Additionally, the agitator ring is adjacent to the inner vessel wall, having a spacing from the inner vessel wall of about 3.8 cm to about 5 cm. An exterior edge of the spiral ribbon is about 0.38 cm to 0.64 cm from the wall. The agitator has a height of 7 m, with an upper diameter of 7 m and a lower-most diameter of 0.5 m. The finisher vessel is inspected after 65 days of production and the inner vessel wall of the finisher vessel, the mixing struts, and the agitator ring is fouled with gelled polymer (e.g., requiring 5.6 shutdowns and cleanings per year with fouling at approximately 65 days).

[0071] Additionally, gel particulate is measured for the finisher agitator during operation. Gel particulate corresponds to gel particles delivered through a screen and further corresponds to gel dislodged from the finisher vessel. The average number of gel particles per day for the finisher assembly is 44.59 gel particles per week.

Example 2 - Finisher Assembly with Mixing Struts Spaced from Inner Vessel Wall.

[0072] The continuous nylon 6,6 manufacturing process of Example 1 is performed, but using a finisher assembly including a finisher agitator with the mixing struts and the agitator ring spaced from the inner vessel wall of the finisher vessel at a distance such that an exterior edge of a spiral ribbon is about 0.38 cm to 0.64 cm from the wall and the mixing struts and agitator ring are about 5.8 cm from the wall. Rotation of the spiral ribbon mechanically engages and generates turbulence in the polymer fluid along an inner vessel wall. Rotating of the mixing struts spaced from the inner vessel wall of the finisher vessel engages and generates turbulence in the polymer fluid. The inner vessel wall is isolated from the turbulence generated by the mixing struts. The finisher vessel is inspected after 65 days of production without evidence of significant fouling. The finisher vessel is inspected after 91 days of production with evidence of gelled polymer fouling along one or more of the inner vessel wall or the mixing struts (e.g., requiring 4 shut downs and cleanings per year with fouling at approximately 91 days). The finisher assembly with the finisher agitator having mixing struts and the agitator ring spaced from the inner vessel wall accordingly realizes a nearly 30 percent increase in operational life before cleaning is necessary. [0073] The gel particulate measured for the finisher assembly, with the mixing struts and the agitator ring recessed, is less than that of the other finisher assembly. The average number of gel particles per unit time for the finisher assembly is 20.82 gel particles per week. The finisher assembly with the recessed mixing struts and the agitator ring realizes nearly a 47 percent decrease in gel particulate.

Example 3 - Finisher Assembly with Mixing Struts Spaced from Inner Vessel Wall and with Baffles.

[0074] Example 2 is followed, but the finisher agitator includes two baffles having perforations coupled with the one or more mixing struts. The baffles are adjacent to the spiral ribbon. One baffle is an upper baffle the other is a lower baffle. The lower baffle is interposed between the upper baffle and the spiral ribbon. The upper baffle is configured to direct polymer fluid downwardly when rotated in a first direction, and the lower baffle is configured to direct polymer fluid upwardly when rotated in the first direction. The baffles reduce stagnation of polymer mixture within the finisher and help remove water from the polymer mixture more efficiently. The baffled agitator gives 1.5 mass per hour greater removal of water from the polymer mixture as compared to Example 2. Example 4 - Finisher Assembly with Mixing Struts Spaced from Inner Vessel Wall and with Mixing Ridges and Notches.

[0075] Example 2 is followed, but the agitator ring includes about 10 mixing ridges along an exterior edge of the ring. The agitator ring also includes 3 notches even spaced within about 0.2 meters of each the mixing ridges, the notches for each mixing ridge disposed on a trailing side of the mixing ridge when the finisher agitator is rotated in a first direction. The notches and mixing ridges reduce stagnation of polymer mixture within the finisher and help remove water from the polymer mixture more efficiently. The notched mixing ridge-equipped agitator gives 0.5 mass per hour greater removal of water from the polymer mixture as compared to Example 2. Example 5- Finisher Assembly with Mixing Struts Spaced from Inner Vessel Wall and with a Scraper Blade.

[0076] Example 2 is followed, but a scraping blade extends from the agitator ring toward the inner vessel wall, and the scraping blade is configured to wipe polymer fluid along the inner vessel wall within the wiping zone. The scraping blade reduces stagnation of polymer mixture within the finisher and helps remove water from the polymer mixture more efficiently. The scraping blade-equipped agitator gives 0.5 mass per hour greater removal of water from the polymer mixture as compared to Example 2.

Example Embodiments

[0077] Example 1 can include subject matter, such as a finisher assembly including a finisher agitator comprising: a finisher vessel including an inner vessel wall extending toward a vessel base having an exit orifice, the inner vessel wall tapering toward the exit orifice, and the inner vessel includes a wiping zone adjacent to the inner vessel wall and a mixing zone remote from the inner vessel wall; and a finisher agitator configured for coupling with a screw of a screw pump, the finisher agitator rotatable relative to the finisher vessel, the finisher agitator including: a spiral ribbon extending from near the exit orifice and along the inner vessel wall, the spiral ribbon including an exterior edge in close proximity to the inner vessel wall and within the wiping zone, and the spiral ribbon is configured to wipe a polymer fluid from along the inner vessel wall within the wiping zone, one or more mixing struts coupled with the spiral ribbon, the one or more mixing struts extend from near the exit orifice and along the spiral ribbon, and an agitator ring coupled with one or more of the spiral ribbon or the one or more mixing struts, and the one or more mixing struts and the agitator ring are spaced from the inner vessel wall and within the mixing zone, one or more of the agitator ring or the one or more mixing struts configured to mix the polymer fluid within the mixing zone remotely from the inner vessel wall.

[0078] Example 2 can include, or can optionally be combined with the subject matter of Example 1, to optionally include wherein in the mixing zone turbulence from the one or more mixing struts or the agitator ring is configured to mix the polymer fluid.

[0079] Example 3 can include, or can optionally be combined with the subject matter of one or any combination of Examples 1 or 2 to optionally include wherein one or more of the agitator ring or the one or more mixing struts ring are configured to mix the polymer fluid in the mixing zone without disturbing gel along the inner vessel wall or along the mixing struts according to the spacing of the agitator ring and the one or more mixing struts from the inner vessel wall.

[0080] Example 4 can include, or can optionally be combined with the subject matter of one or any combination of Examples 1 through 3 to optionally include wherein an interior edge of the spiral ribbon extends inwardly into the mixing zone, and the one or more mixing struts are coupled with the spiral ribbon adjacent to the interior edge of the spiral ribbon.

[0081] Example 5 can include, or can optionally be combined with the subject matter of one or any combination of Examples 1-4 to optionally include wherein the spiral ribbon has a width of between about 2.5 cm to at least 20 cm between the exterior edge and the interior edge, or about 5.8 cm to at least 20 cm between the exterior edge and the interior edge (e.g., about 2.5 cm, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or about 20 cm or more, and the one or more mixing struts are spaced from the inner vessel wall at least 2.5 cm, or spaced from the inner vessel wall at least 5.8 cm (e.g., about 2.5 cm, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or about 20 cm or more).

[0082] Example 6 can include, or can optionally be combined with the subject matter of Examples 1-5 to optionally include wherein the finisher agitator includes one or more baffles having perforations coupled with the one or more mixing struts, the one or more baffles adjacent to the spiral ribbon.

[0083] Example 7 can include, or can optionally be combined with the subject matter of Examples 1-6 to optionally include wherein the one or more baffles include an upper baffle and a lower baffle, the lower baffle interposed between the upper baffle and the spiral ribbon, the upper baffle is configured to direct the polymer fluid toward the exit orifice with rotation in a first direction, and the lower baffle is configured to direct the polymer fluid away from the exit orifice with rotation in the first direction.

[0084] Example 8 can include, or can optionally be combined with the subject matter of Examples 1-7 to optionally include wherein the agitator ring includes one or more mixing ridges along a ring exterior edge.

[0085] Example 9 can include, or can optionally be combined with the subject matter of Examples 1-8 to optionally include wherein the agitator ring includes one or more notches adjacent to one or more of the mixing ridges, the one or more notches on a trailing side of one or more of the mixing ridges when the finisher agitator is rotated in a first direction.

[0086] Example 10 can include, or can optionally be combined with the subject matter of Examples 1-9 to optionally include a screw pump including a screw extending through the exit orifice, and the finisher agitator is coupled with the screw and rotatable according to rotation of the screw.

[0087] Example 11 can include, or can optionally be combined with the subject matter of Examples 1-10 to optionally include wherein the finisher agitator includes an elevating support coupled with the screw, the elevating support elevates the finisher agitator within the finisher vessel.

[0088] Example 12 can include, or can optionally be combined with the subject matter of Examples 1-11 to optionally include wherein the one or more mixing struts and the agitator ring are spaced from the inner vessel wall according to the elevation provided by the elevating support.

[0089] Example 13 can include, or can optionally be combined with the subject matter of Examples 1-12 to optionally include wherein a scraping blade extends from the agitator ring toward the inner vessel wall, and the scraping blade is configured to wipe polymer fluid along the inner vessel wall within the wiping zone.

[0090] Example 14 can include, or can optionally be combined with the subject matter of Examples 1-13 to optionally include a finisher agitator comprising: a spiral ribbon extending from a spiral base to a spiral end, the spiral ribbon expanding from the spiral base to the spiral end, the spiral ribbon including an exterior edge configured for wiping a polymer fluid from an inner vessel wall of a finisher vessel when installed in the finisher vessel; one or more mixing struts coupled along the spiral ribbon from near the spiral base toward the spiral end, the one or more mixing struts configured to mix the polymer fluid; and an agitator ring coupled with one or more of the spiral ribbon or the one or more mixing struts, wherein the agitator ring is recessed from the inner vessel wall when installed in the finisher vessel relative to the exterior edge of the of spiral ribbon in close proximity to the inner vessel wall, and the recessed agitator ring is isolated from the inner vessel wall.

[0091] Example 15 can include, or can optionally be combined with the subject matter of Examples 1-14 to optionally include wherein the finisher agitator includes an elevating support near the spiral base, the elevating support elevates the finisher agitator within the finisher vessel when installed.

[0092] Example 16 can include, or can optionally be combined with the subject matter of Examples 1-15 to optionally include wherein the agitator ring is recessed from the inner vessel wall according to the elevation provided by the elevating support.

[0093] Example 17 can include, or can optionally be combined with the subject matter of Examples 1-16 to optionally include wherein the one or more mixing struts are recessed from the inner vessel wall according to the elevation provided by the elevating support, and the one or more recessed mixing struts are isolated from the inner vessel wall.

[0094] Example 18 can include, or can optionally be combined with the subject matter of Examples 1-17 to optionally include wherein the finisher agitator is configured for rotation within the finisher vessel, and when rotated the one or more mixing struts and the agitator ring are configured to mix the polymer fluid without disturbing gel along the inner vessel wall or along the mixing struts according to the recessing of the agitator ring from the inner vessel wall and recessing of the one or more mixings struts from the inner vessel wall when installed.

[0095] Example 19 can include, or can optionally be combined with the subject matter of Examples 1-18 to optionally include wherein the finisher agitator includes one or more baffles having perforations coupled with one or more of the agitator ring or the one or more mixing struts.

[0096] Example 20 can include, or can optionally be combined with the subject matter of Examples 1-19 to optionally include wherein the one or more baffles include an upper baffle and a lower baffle, the lower baffle interposed between the upper baffle and the spiral ribbon, the upper baffle is configured to direct polymer fluid downwardly when rotated in a first direction, and the lower baffle is configured to direct polymer fluid upwardly when rotated in the first direction.

[0097] Example 21 can include, or can optionally be combined with the subject matter of Examples 1-20 to optionally include wherein the agitator ring includes one or more mixing ridges along a ring exterior edge.

[0098] Example 22 can include, or can optionally be combined with the subject matter of Examples 1-21 to optionally include wherein the agitator ring includes one or more notches adjacent to one or more of the mixing ridges, the one or more notches on a trailing side of one or more of the mixing ridges.

[0099] Example 23 can include, or can optionally be combined with the subject matter of Examples 1-22 to optionally include wherein a scraping blade extends from the agitator ring, when installed in the finisher vessel the scraping blade extends toward the inner vessel wall, and the scraping blade is configured to wipe polymer fluid along the inner vessel wall.

[00100] Example 24 can include, or can optionally be combined with the subject matter of Examples 1-23 to optionally include a method of using a finisher assembly including a finisher agitator comprising: agitating a polymer fluid within a melt pool of a finisher vessel with a finisher agitator including: wiping the polymer fluid along an inner vessel wall with a spiral ribbon of the finisher agitator, and mixing the polymer fluid with one or more of an agitator ring and one or more mixing struts coupled with the spiral ribbon, the agitator ring and the one or more mixing struts spaced from the inner vessel wall; and isolating the agitator ring from gel formed along the inner vessel wall or isolating the inner vessel wall from gel formed on one or more of the mixing struts according to spacing of the agitator ring and the one or more mixing struts from the inner vessel wall. [00101] Example 25 can include, or can optionally be combined with the subject matter of Examples 1-24 to optionally include wherein wiping the polymer fluid includes mechanically engaging the polymer fluid with the spiral ribbon, and generating turbulence with the spiral ribbon along the inner vessel wall.

[00102] Example 26 can include, or can optionally be combined with the subject matter of Examples 1-25 to optionally include wherein isolating one or more of the agitator ring or the one or more mixing struts from gel includes spacing the agitator ring and the one or more mixing struts away from the inner vessel wall relative to an exterior edge of the spiral ribbon in close proximity to the inner vessel wall.

[00103] Example 27 can include, or can optionally be combined with the subject matter of Examples 1-26 to optionally include isolating the inner vessel wall from gel formed along one or more of the agitator ring or the one or more mixing struts according to spacing of the agitator ring and the one or more mixing struts from the inner vessel wall.

[00104] Example 28 can include, or can optionally be combined with the subject matter of Examples 1-27 to optionally include retaining gel formed along one or more of the inner vessel wall, the agitator ring, or the one or more mixing struts during agitation according to spacing of the agitator ring and the one or more mixing struts from the inner vessel wall.

[00105] Example 29 can include, or can optionally be combined with the subject matter of Examples 1-28 to optionally include wherein mixing the polymer fluid with the agitator ring includes mixing the polymer fluid with the agitator ring having one or more mixing ridges along a ring exterior edge.

[00106] Example 30 can include, or can optionally be combined with the subject matter of Examples 1-29 to optionally include wherein mixing the polymer fluid with the agitator ring includes mixing the polymer fluid with the agitator ring having one or more notches on a trailing side of one or more of the mixing ridges.

[00107] Example 31 can include, or can optionally be combined with the subject matter of Examples 1-30 to optionally include separating a mixed flow of steam and polymer fluid with a separator helix within a barrel of a finisher nozzle, the finisher nozzle configured to deliver polymer fluid to the finisher vessel. [00108] Example 32 can include, or can optionally be combined with the subject matter of Examples 1-31 to optionally include delivering the separated polymer fluid to the melt pool of polymer fluid with the finisher nozzle; and isolating the inner vessel wall from spattering of the separated polymer fluid according to the barrel having a substantially constant inner area.

[00109] Example 33 can include, or can optionally be combined with the subject matter of Examples 1-32 to optionally include delivering the polymer fluid through an exit orifice of the finisher vessel with a screw pump including a screw, the finisher agitator coupled with the screw.

[00110] Each of these non-limiting examples can stand on its own, or can be combined in any permutation or combination with any one or more of the other examples.

[00111] The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments in which the disclosure can be practiced.

These embodiments are also referred to herein as "examples." Such examples can include elements in addition to those shown or described. However, the present inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the present inventors also contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.

[00112] In the event of inconsistent usages between this document and any documents so incorporated by reference, the usage in this document controls.

[00113] In this document, the terms "a" or "an" are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of "at least one" or "one or more." In this document, the term "or" is used to refer to a nonexclusive or, such that "A or B" includes "A but not B," "B but not A," and "A and B," unless otherwise indicated. In this document, the terms "including" and "in which" are used as the plain-English equivalents of the respective terms "comprising" and "wherein." Also, in the following claims, the terms "including" and "comprising" are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[00114] Method examples described herein can be machine or computer- implemented at least in part. Some examples can include a computer-readable medium or machine-readable medium encoded with instructions operable to configure an electronic device to perform methods as described in the above examples. An implementation of such methods can include code, such as microcode, assembly language code, a higher- level language code, or the like. Such code can include computer readable instructions for performing various methods. The code may form portions of computer program products. Further, in an example, the code can be tangibly stored on one or more volatile, no n- transitory, or nonvolatile tangible computer-readable media, such as during execution or at other times. Examples of these tangible computer-readable media can include, but are not limited to, hard disks, removable magnetic disks, removable optical disks (e.g., compact disks and digital video disks), magnetic cassettes, memory cards or sticks, random access memories (RAMs), read only memories (ROMs), and the like.

[00115] The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other embodiments can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. § 1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the

understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the Detailed Description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that such embodiments can be combined with each other in various combinations or permutations. The scope of the disclosure should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.