SEDIMENTATION TYPE LIQUID-LIQUID SEPARATOR TECHNICAL FIELD

[0001]

The present invention relates to a sedimentation type liquid-liquid separator. More specifically, the invention relates to a sedimentation type liquid-liquid separator that separates a liquid mixture, in which liquids such as oil and water with different specific gravities are mixed with each other while forming an interface therebetween, into respective liquids.

BACKGROUND ART

[0002]

Hitherto, as a device that separates a liquid mixture in which liquids such as water and oil with different specific gravities are mixed with each other while forming an interface therebetween into respective liquids, a device which performs a settling treatment using the difference in specific gravity has been developed (for example, see Patent Documents 1 and 2).

[0003]

Patent Document 1 discloses a suspension separating device including a rectification plate and an inclined passageway assembly which includes an inclined passageway inclined with respect to a passageway, wherein both are installed in the passageway of the liquid mixture, and a liquid mixture which becomes a parallel laminar flow by the rectification plate is made to flow into the inclined passageway, so that a liquid with high specific gravity is separated from a main liquid with a low specific gravity as a sedimentation liquid through settlement.

[0004]

Patent Document 2 discloses a sedimentation type liquid-liquid separator including: a main body portion which includes a hollow cylindrical body portion, wherein the inside of the main body portion is equipped with a rectification member and a sedimentation member used to settle a sedimentation liquid with a high specific gravity in the liquid mixture passing through the rectification member.

Then, in the sedimentation type liquid-liquid separator of Patent Document 2, the liquid mixture enters similar to a laminar state by the rectification member, and the liquid mixture which enters similar to a laminar state is supplied to a region provided with the sedimentation member, so that the separation of the liquid mixture is promoted in the sedimentation member.

[0005]

However, in the techniques of Patent Documents 1 and 2, the inclined passageway or the sedimentation member includes plural passageways through which the liquid mixture flows. For this reason, it is desirable that all passageways serve to separate the liquids with substantially the same efficiency so that the inclined

passageway or the sedimentation member efficiently separates the liquid. Specifically, it is desirable that the flow rates and the states of the liquid mixtures supplied to all passageways be the same (that is, the mixture ratio between the main liquid and the sedimentation liquid in the liquid mixture be the same).

[0006]

However, penetration holes which have the same diameter are formed in the rectification plate or the rectification member of Patent Documents 1 and 2. For this reason, the flow of the liquid mixture may be made to be similar to the laminar flow in a manner such that the liquid mixture is made to pass through the rectification plate or the rectification member, but the speed of the liquid mixture in the cross-section of the body portion may not be made to be uniform. This is because a large amount of main liquid tends to flow toward the upper portion of the liquid mixture, whereas a small amount of sedimentation liquid tends to flow toward the lower portion of the liquid mixture. Then, with regard to the speed of the liquid mixture which passes through the rectification plate due to the difference in the flow rate of both, the speed becomes faster at the upper portion where the large amount of main liquid tends to flow than the lower portion.

Accordingly, there is a possibility that a circulating flow may occur before and after the rectification plate (between the rectification plate and the sedimentation member).

When such a circulating flow occurs, in a portion where a flow which is directed toward the sedimentation member occurs in the circulating flow, the speed of the liquid mixture becomes faster. Accordingly, the distance necessary for settling the sedimentation liquid from the main liquid becomes longer. On the other hand, in a portion where the flow which is directed to the direction opposite to the direction of the sedimentation member, the sedimentation member may not be utilized.

[0007]

Further, even in the rectification plate or the rectification member of Patent Documents 1 and 2, when a penetration hole with a small hole diameter is formed, a pressure loss generated when the liquid mixture passes through the rectification plate or the rectification member increases. Then, since the difference in speed between the fluids which pass through the upper and lower portions of the rectification plate or the rectification member may be decreased, there is a possibility that the occurrence of the circulating flow may be prevented. However, when the pressure loss generated when the liquid mixture passes through the rectification plate or the rectification member increases, the sedimentation liquid contained in the liquid mixture is separated (is changed into small particles) when the liquid mixture passes through the rectification plate or the rectification member, which degrades the separating efficiency of the sedimentation member that separates the sedimentation liquid from the main liquid.

[0008]

Furthermore, even when the circulating flow occurs before and after the rectification plate or the rectification member after installing the rectification plate or the rectification member, the circulating flow is not strong enough to promote the mixture between the main liquid and the sedimentation liquid. Accordingly, the mixture ratio between the main liquid and the sedimentation liquid contained in the liquid mixture is almost the same before and after the rectification plate or the rectification member. As described above, with regard to the liquid mixture which does not pass through the rectification plate or the rectification member, in general, a large ratio of a main liquid with a low specific gravity is present at the upper portion of the liquid mixture, and a large ratio of a sedimentation liquid with a high specific gravity is present at the lower portion thereof. For this reason, the mixture ratio of the liquid mixture which has passed through the rectification plate or the rectification member is the same, and with regard to the state of the liquid mixture which is supplied to the inclined passageway or the sedimentation member, the mixed state therebetween may be different due to the passageway. Then, in a portion to which a liquid mixture containing a small ratio of sedimentation liquid is supplied, an excessive liquid separating function may be exhibited. In a portion to which a liquid mixture containing a large ratio of

sedimentation liquid is supplied, a sufficient liquid separating function may not be exhibited. [0009]

As described above, in the techniques of Patent Documents 1 and 2, the flow of the liquid mixture may be made similar to the laminar flow to a certain extent by installing the rectification plate or the rectification member, but it is difficult to sufficiently improve the separating efficiency in the inclined passageway or the sedimentation member.

CITATION LIST

PATENT DOCUMENTS

[0010]

[Patent Document 1 ] Japanese Patent No. 3681003

[Patent Document 2] Japanese Patent Application Laid-Open No.

2009-178654

DISCLOSURE OF INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0011]

The invention is made in view of the above-described circumstances, and it is an object of the invention to provide a sedimentation type liquid-liquid separator capable of improving liquid separating efficiency by efficiently exhibiting a liquid separating function.

MEANS TO SOLVE THE PROBLEMS

[0012]

According to a first invention, there is provided a sedimentation type liquid-liquid separator that separates a liquid mixture, in which liquids with different specific gravities are mixed with each other while forming an interface therebetween, into respective liquids, the sedimentation type liquid-liquid separator including: a main body portion that includes a hollow cylindrical body portion including a liquid path formed therein, an inflow path installed at the front end of the body portion and supplying the liquid mixture to the liquid path of the body portion, and a discharge path installed at the rear end of the body portion and discharging a separated liquid from the body portion; a sedimentation member that settles a liquid with a high specific gravity contained in the liquid mixture inside the main body portion; and a rectification member that is installed between the sedimentation member and the inflow path inside the main body portion, wherein the rectification member includes an upstream rectification member that is equipped with a plurality of penetration holes with different hole diameters and a downstream rectification member that is disposed near the sedimentation member in relation to the upstream rectification member and is equipped with penetration holes with a uniform hole diameter, and wherein in the penetration holes of the upstream rectification member, the sizes of the penetration holes formed in the upper and lower portions thereof are different from each other.

According to a second invention, in the sedimentation type liquid-liquid separator of the first invention, the inflow path is disposed so as to face the front-end inner surface of the body portion so that the liquid mixture is supplied from the direction along the axial direction of the liquid path.

According to a third invention, in the sedimentation type liquid-liquid separator of the first invention, the upstream rectification member is equipped with a collision portion that is installed at a portion intersecting with the axial extension line of the inflow path so that the liquid does not pass therethrough. According to a fourth invention, in the sedimentation type liquid-liquid separator of any one of the first to third inventions, a supply port of the inflow path is disposed inside the liquid path of the body portion so as to be located at a position where a free surface of a liquid with a high specific gravity settling inside the liquid path is formed.

EFFECT OF THE INVENTION

[0013]

According to the first invention, in the upstream rectification member, the sizes of the penetration holes which are formed at the upper and lower portions thereof are different from each other. Then, in a case where the hole diameter of the penetration hole formed at the upper portion is larger than that of the penetration hole formed at the lower portion, the liquid mixture may easily pass through the upper portion of the upstream rectification member compared to the lower portion thereof. On the contrary, in a case where the hole diameter of the penetration hole formed at the lower portion is larger than that of the penetration hole formed at the upper portion, the liquid mixture may easily pass through the lower portion of the upstream rectification member compared to the upper portion thereof. For this reason, in a case where the liquid mixture contains a large ratio of a liquid with a high specific gravity

(high-specific-gravity liquid), when the hole diameter of the penetration hole formed at the upper portion is set to be larger than that of the penetration hole formed at the lower portion, the ratio of the high-specific-gravity liquid which passes through the upper portion of the upstream rectification member may be increased compared to the case where the upstream rectification member is provided with penetration holes with the uniform hole diameter. Then, since the flow rate of the liquid mixture which has passed through the upstream rectification member may be made to be almost uniform within the cross-section of the body portion, the function of making the flow rate of the liquid mixture uniform using the downstream rectification member may be improved.

Furthermore, since a comparatively large amount of high-specific-gravity liquid which easily passes through the lower portion of the upstream rectification member may pass through the upper portion of the upstream rectification member, the uniform mixture ratio of the liquid mixture may be promoted in a manner such that a certain amount of high-specific-gravity liquid settles between the upstream rectification member and the downstream rectification member. In the same way, in a case where the liquid mixture contains a large ratio of a liquid with a low specific gravity (low-specific-gravity liquid), when the hole diameter of the penetration hole formed at the lower portion is set to be larger than that of the penetration hole formed at the upper portion, the ratio of the low-specific-gravity liquid which passes through the lower portion of the upstream rectification member may be increased compared to the case where the upstream rectification member is provided with penetration holes with the uniform hole diameter. Then, since the flow rate of the liquid mixture which has passed through the upstream rectification member may be made to be almost uniform within the cross-section of the body portion, the function of making the flow rate of the liquid mixture uniform using the downstream rectification member may be improved. Furthermore, since a comparatively large amount of low-specific-gravity liquid which easily passes through the upper portion of the upstream rectification member may be made to pass through the lower portion of the upstream rectification member, the uniform mixture ratio of the liquid mixture between both plates may be promoted in a manner such that the amount of the low-specific-gravity liquid increases somewhat between the upstream rectification member and the downstream rectification member. Accordingly, since the state of the liquid mixture which has passed through the rectification member may be made to be uniform within the cross-section of the body portion, the liquid may be separated with substantially the same efficiency in all passageways in the sedimentation member, and the liquid separating efficiency in the sedimentation member, that is, the liquid separating efficiency of the device may be improved.

According to the second invention, when the liquid mixture is supplied from the inflow path toward the inner surface of the front end of the body portion, the liquid mixture which is supplied from the supply port of the inflow path flows in the direction opposite to the direction where the liquid mixture flows inside the liquid path of the body portion (hereinafter, referred to as a main direction), so that the liquid mixture collides with the inner surface of the front end of the body portion. Then, since the liquid mixture which is supplied from the supply port of the inflow path first stays in the vicinity of the inner surface of the front end of the body portion when the liquid mixture collides with the inner surface of the front end of the body portion, and flows in the main direction while the flowing direction is changed, the flow of the liquid mixture becomes a low-speed flow compared to the state where the liquid mixture is supplied from the supply port of the inflow path, and the liquid mixture flows toward the rectification member inside the liquid path. Furthermore, since the liquid mixture collides with the inner surface of the front end of the body portion, a substantially radial flow is formed along the inner surface of the front end of the body portion so that the flow speeds are substantially the same in any direction, and then the liquid mixture may flow toward the main direction. Then, the state of the liquid mixture may be set such that the flow rate is substantially uniform and the mixed state is substantially within the cross-section of the body portion until the liquid mixture is supplied to the rectification member. That is, since the state of the liquid mixture may be made to be uniform to a certain extent within the cross-section of the body portion until the liquid mixture reaches the rectification member, the state of the liquid mixture which has passed through the rectification member may be made to be more uniform.

According to the third invention, since the liquid mixture which flows through the inflow path from the outside may be prevented from flowing through the upstream rectification member, it is possible to maintain a function of equalizing the liquid mixture between the upstream rectification member and the downstream rectification member and a function of decreasing the ratio of a sub-liquid in the liquid mixture. Accordingly, it is possible to further improve the liquid separating efficiency of the device.

According to the fourth invention, since the liquid mixture is not easily stirred inside the body portion when the liquid mixture is supplied from the supply port of the inflow path, it is possible to suppress the separated liquids from being mixed with each other again. Then, it is possible to suppress the degradation of the liquid separating efficiency which is caused when the separated liquids are mixed with each other again.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014]

FIG 1 is a schematic cross-sectional view illustrating a sedimentation type liquid-liquid separator of the embodiment.

FIG 2(A) is a cross-sectional view taken along the line A-A of FIG. 1 , FIG. 2(B) is a cross-sectional view taken along the line B-B of FIG 1, and FIG 2(C) is a

cross-sectional view taken along the line C-C of FIG. 1.

FIG 3(A) is a schematic cross-sectional view illustrating a sedimentation type liquid-liquid separator of another embodiment and FIG 3(B) is a cross-sectional view taken along the line B-B of FIG. 1. FIG 4 is a schematic diagram illustrating a sedimentation type liquid-liquid separator of Comparative example, where FIG 4(A) is a cross-sectional view, FIG. 4(B) is a cross-sectional view taken along the line B-B of FIG 4(A), and FIG 4(C) is a cross-sectional view taken along the line C-C of FIG. 4(A).

FIG 5 is a diagram illustrating a calculation result of a status inside a separator of Comparative example, where FIG 5(A) illustrates a flow speed distribution and FIG. 5(B) illustrates a calculation result of a water volume ratio distribution.

FIG. 6 is a diagram illustrating a calculation result of a status inside a separator of Example, where FIG 6(A) illustrates a flow speed distribution and FIG 6(B) illustrates a calculation result of a water volume ratio distribution.

MODE FOR CARRYING OUT THE INVENTION

[0015]

Next, an embodiment of the invention will be described by referring to the drawings.

A sedimentation type liquid-liquid separator of the embodiment is a device that separates a liquid mixture in which liquids with different specific gravities are mixed with each other while forming an interface therebetween into respective liquids, and is a device which is appropriate for a facility such as a chemical plant or a treatment device where a liquid mixture needs to be continuously treated.

In particular, even in the case of a liquid mixture in which the difference in the mixture ratio between the respective liquids is comparatively small, the liquid mixture may be efficiently separated into respective liquids.

[0016]

Furthermore, the liquid mixture in which liquids with different specific gravities are mixed with each other while forming an interface therebetween indicates, for example, a liquid mixture which is formed by mixing oil and water or oil and alcohol. Specifically, a liquid with a low mixture ratio is dispersed in the form of liquid droplets in a liquid with a high mixture ratio contained in the liquid mixture. Then, the liquid mixture which is separated into respective liquids by the sedimentation type liquid-liquid separator of the embodiment may be a liquid mixture in which liquids with different specific gravities are mixed with each other while forming an interface therebetween, although the type of the liquid which is mixed in the liquid mixture is not particularly limited.

[0017]

Hereinafter, a liquid with a low specific gravity in a liquid mixture is referred to as a low-specific-gravity liquid, and a liquid with higher specific gravity than that of the low-specific-gravity liquid is referred to as a sedimentation liquid.

Further, in the liquid mixture which is separated by the sedimentation type liquid-liquid separator of the embodiment, the mixture ratio between the

low-specific-gravity liquid and the sedimentation liquid is not particularly limited, but hereinafter, a case will be representatively described in which the sedimentation liquid is mixed in the low-specific-gravity liquid. That is, a case will be representatively described in which the liquid mixture formed by dispersing the sedimentation liquid in the low-specific-gravity liquid in the form of liquid droplets is separated into the low-specific-gravity liquid and the sedimentation liquid.

[0018]

(Description of entire structure of sedimentation type liquid-liquid separator 1 of embodiment)

In FIG 1 , the reference sign 10 indicates a sedimentation type liquid-liquid separator 1 of the embodiment (hereinafter, simply referred to as a separator 1) of a main body portion. A main body portion 10 is a hollow container that includes a hollow cylindrical body portion 11 and barrelheads 12 and 13 provided at both ends of the body portion 11 in the axial direction. For example, in a case where the separator 1 of the embodiment is used in a chemical plant, the main body portion 10 in which the inner diameter of the body portion 11 is about several m and the axial length is several times the inner diameter of the body portion 11 is used, but the main body portion 10 is not particularly limited to the above-described size, and may be freely determined depending on the amount, the property, or the like of a liquid to be treated.

[0019]

The left end (the front end) of the body portion 11 is equipped with an inflow path 14 which is used to supply a liquid mixture into the main body portion 10. The inflow path 14 is a tubular member which is disposed at the side surface of the body portion 11. With regard to the inflow path 14, the upper end thereof protrudes to the outside of the main body portion 10 and the lower end thereof is disposed inside the main body portion 10.

Furthermore, the lower end of the inflow path 14 is disposed so as to be positioned at a height of the interface (the free interface FS) between the sedimentation liquid accumulated in the lower portion of the main body portion 10 and the liquid mixture. Then, a supply port 14a which supplies the liquid mixture into the body portion 11 of the main body portion 10 is provided at the side surface of the inflow path 14 near the front-end barrelhead 12 (the front-end barrelhead 12), the reason for which will be described later.

[0020]

As shown in FIG 1, the right end side (the rear end side) of the inflow path 14 is provided with two rectification members 21 and 22 and a sedimentation member 23 which are arranged in this order. The two rectification members 21 and 22 and the sedimentation member 23 are provided so as to separate the liquid mixture into the low-specific-gravity liquid and the sedimentation liquid, the details of which will be described later.

[0021]

In the vicinity of the rear end of the main body portion 10, a separation plate lOd which divides the inside of the body portion 11 of the main body portion 10 is provided between the sedimentation member 23 and the barrelhead 13 (the rear-end barrelhead 12). Specifically, the separation plate lOd is installed so as to divide the inside of the body portion 11 into a liquid separation space and a low-specific-gravity liquid discharge space. Furthermore, the liquid separation space is a space where the sedimentation member 23 is accommodated.

The separation plate lOd is formed so that a communication path lOf is formed between the upper end thereof and the inner surface of the body portion 11 for the purpose of the communication between both spaces. For this reason, the liquid positioned at the upper portion of the liquid separation space, that is, the

low-specific-gravity liquid may be made to flow into the low-specific-gravity liquid discharge space through the communication path 1 Of.

[0022]

Then, the rear end of the main body portion 10 is equipped with discharge paths 11a and lib which discharge a liquid from the inside of the main body portion 10 to the outside thereof.

[0023]

In the vicinity of the rear end of the body portion 11 , a sedimentation liquid discharge path 1 la is installed at the lower portion of the liquid separation space near the separation plate lOd. The sedimentation liquid discharge path 1 la is a path which is used to discharge the sedimentation liquid separated from the low-specific-gravity liquid to the outside. The sedimentation liquid discharge path 1 la is equipped with a mechanism (for example, a valve or the like) capable of interrupting the communication between the inside and the outside of the main body portion 10, and is configured to discharge the sedimentation liquid from the sedimentation liquid discharge path 1 la at a predetermined period. Specifically, the discharge amount of the sedimentation liquid is adjusted so that the amount of the sedimentation liquid accumulated in the lower portion of the body portion 11 becomes a predetermined amount (that is, a predetermined depth).

[0024]

On the other hand, in the rear end of the body portion 11, a low-specific-gravity liquid discharge path 1 lb is installed at the lower portion of the low-specific-gravity liquid discharge space near the separation plate lOd. The low-specific-gravity liquid discharge path 1 lb is a path which is used to discharge the low-specific-gravity liquid, flowing into the low-specific-gravity liquid discharge space through the communication path lOf after the sedimentation liquid is separated, to the outside therethrough. The low-specific-gravity liquid discharge path 1 lb is equipped with a mechanism (for example, a valve or the like) capable of interrupting a communication between the inside and the outside of the main body portion 10, and adjusts the flow rate of the

low-specific-gravity liquid discharged from the low-specific-gravity liquid discharge path lib. Specifically, the liquid level of the low-specific-gravity liquid is adjusted to be constant.

[0025]

With the above-described configuration, when the liquid mixture is supplied from the inflow path 14 installed at the front end of the main body portion 10, the liquid mixture may be supplied into the body portion 11 of the main body portion 10.

Since the rear end of the main body portion 10 is equipped with the discharge paths 11a and lib, the liquid mixture flows inside the body portion 11 from the inflow path 14 toward the discharge paths 11a and 1 lb (that is, from the front end of the main body portion 10 toward the rear end thereof).

Then, in the inside of the body portion 11, the two rectification member 21 and 22 and the sedimentation member 23 are installed between the inflow path 14 and the discharge paths 11a and lib. Accordingly, the sedimentation liquid is separated from the low-specific-gravity liquid during a time when the liquid mixture flows from the inflow path 14 to the discharge paths 1 la and 1 lb.

Then, since the sedimentation liquid is accumulated in the lower portion of the liquid separation space, only the low-specific-gravity liquid positioned at the upper portion of the liquid separation space flows from the communication path 1 Of into the low-specific-gravity liquid discharge space. For this reason, the respective liquids which are separated inside the liquid separation space may be respectively discharged from the discharge paths 11a and 1 lb without being mixed with each other again.

That is, in the separator 1 of the embodiment, when the liquid mixture is supplied from the inflow path 14 into the body portion 11 , the liquid mixture may be separated into the low-specific-gravity liquid and the sedimentation liquid, and the respective separated liquids may be collected.

[0026]

Furthermore, it is needless to mention that the low-specific-gravity liquid which is discharged from the low-specific-gravity liquid discharge path lib does not mean only the state where the sedimentation liquid is rarely contained, but the state where the ratio of the sedimentation liquid decreases compared to the liquid mixture supplied from the inflow path 14. In the same way, it is needless to mention that the sedimentation liquid which is discharged from the sedimentation liquid discharge path 11a does not mean only the state where the low-specific-gravity liquid is rarely contained, but also the state where the low-specific-gravity liquid is somewhat contained.

[0027]

Further, a gas discharge portion 1 le is installed above the front end of the body portion 11. The gas discharge portion 11 e is equipped with a mechanism (for example, a valve or the like) capable of interrupting communication between the inside and the outside of the main body portion 10, and is configured to appropriately discharge a gas accumulated inside the main body portion 10.

[0028]

(Detailed description of respective constituents)

Next, the respective constituents of the sedimentation type liquid-liquid separator of the embodiment 1 will be described in detail.

[0029]

(Description of two rectification members 21 and 22)

In the separator 1 of the embodiment, in order to improve the separation effect, the two rectification members 21 and 22 and the sedimentation member 23 are provided inside the body portion 11 of the main body portion 10.

[0030]

As shown in FIG 1, the two rectification members 21 and 22 which divide the inside of the body portion 11 of the main body portion 10 are provided between the inflow path 14 and the sedimentation member 23. Specifically, the two rectification members 21 and 22 are installed so as to divide the front end of the body portion 11 into the liquid supply space and the liquid separation space. Furthermore, as described above, the liquid separation space is a space where the sedimentation member 23 is accommodated and the liquid supply space is a space where the inflow path 14 is accommodated.

[0031]

The two rectification members 21 and 22 are both a plate-like member, and have plural penetration holes which penetrate the front and rear surfaces thereof (FIGS. 2(A) and 2(B)).

[0032]

First, in the two rectification members 21 and 22, the rectification member 21 positioned near the inflow path 14 (hereinafter, referred to as the upstream rectification member 21 ) is a plate-like member with plural penetration holes. The upstream rectification member 21 is provided with plural penetration holes 21a and 21b which have different hole diameters. For example, as shown in FIG. 2(A), in the upstream rectification member 21 , a region provided with the penetration hole 21 a having a large hole diameter (the upper region 21 A) is provided at the upper portion, and a region provided with the penetration hole 21b having a small hole diameter (the lower region 2 IB) is provided at the lower portion. Then, the upper region 21 A is formed so that the area thereof becomes smaller than that of the lower region 2 IB.

[0033]

Further, the rectification member 22 (hereinafter, referred to as the downstream rectification member 22) is also a plate-like member provided with plural penetration holes. The downstream rectification member 22 is formed so that the penetration holes 22h having the same hole diameter are provided, in contrast to the case of the upstream rectification member 21. The hole diameter of the penetration hole 22h is not particularly limited, but it is desirable that the hole diameter be approximately equal to the penetration hole 21a of the upstream rectification member 21 in order to effectively exhibit the rectification effect.

[0034]

When the two rectification members 21 and 22 with the above-described structure are provided, the following effect may be obtained.

[0035]

First, in the liquid mixture which flows toward the upstream rectification member 21, since the specific gravity of the sedimentation liquid is larger than the specific gravity of the low-specific-gravity liquid, the flow of the sedimentation liquid which is directed toward the lower portion of the upstream rectification member 21 is generated. For this reason, in the flow of the liquid mixture which is directed toward the upstream rectification member 21, the flow speed of the lower portion may easily become faster than that of the upper portion.

[0036]

On the other hand, in the upstream rectification member 21, the penetration hole 21b formed in the lower region 21 B is smaller than the penetration hole 21a formed in the upper region 21 A. Accordingly, the liquid mixture may not easily pass through the lower portion of the upstream rectification member 21 (the portion of the lower region 21B) compared to the upper portion (the portion of the upper region 21 A). That is, the resistance acting on the passage of the liquid mixture becomes larger at the lower portion of the upstream rectification member 21 compared to the upper portion thereof.

[0037]

Then, at the time when the liquid mixture passes through the upstream rectification member 21, since the flow of the liquid mixture passing through the lower region 2 IB is suppressed more than the flow of the liquid mixture passing through the upper region 21 A, it is possible to decrease the difference in the flow speed of the liquid mixture between the upper and lower portions at the position where the liquid mixture passes through the upstream rectification member 21. That is, it is possible to decrease the difference in the flow speed of the fluid mixture at respective positions within the cross-section of the liquid path lOh and make the flow rate of the liquid mixture umform within the cross-section of the liquid path lOh.

[0038]

Then, since the liquid mixture which passes through the upstream rectification member 21 passes through the downstream rectification member 22 provided with the uniform penetration holes 22h, it is possible to further decrease the difference in flow speed of the liquid mixture at respective positions within the cross-section of the liquid path lOh.

Then, since it is possible to prevent a circulating flow from occurring at the position where the liquid mixture passes through the downstream rectification member 22 due to the difference in the flow speed of the liquid mixture, it is possible to prevent the difference in distance which is necessary for separating the low-specific-gravity liquid and the sedimentation liquid formed when the circulating flow is generated (the distance necessary for settling the sedimentation liquid).

[0039]

Further, if the flow of the liquid mixture passing through the lower region 2 IB is more suppressed than the flow of the liquid mixture passing through the upper region 21 A when the liquid mixture passes through the upstream rectification member 21, a part of the liquid mixture which flows toward the lower region 21 B may flow toward the upper region 21 A. That is, a comparatively large amount of sedimentation liquid may pass through the upper region 21 A of the upstream rectification member 21 compared to the case where the upstream rectification member 21 is provided with the penetration holes having the same hole diameter. Then, the mixing of the low-specific-gravity liquid and the sedimentation liquid contained in the liquid mixture between the rectification members 21 and 22 is performed depending on how much the sedimentation liquid passing through the upper region 21 A settles between the upstream rectification member 21 and the downstream rectification member 22, and the difference in the mixture ratio of both liquids in the liquid mixture within the cross-section of the liquid path lOh may be decreased.

[0040]

That is, since the two rectification members 21 and 22 are provided, it is possible to decrease the difference in the state (the flow rate, the mixture ratio, or the like) of the liquid mixture supplied to the sedimentation member 23 within the cross-section of the liquid path lOh.

[0041]

(Description of two rectification members 21 and 22 in the case of

sedimentation liquid>low-specific-gravity liquid)

Furthermore, in the above-described example, a case has been described in which the amount of the low-specific-gravity liquid is larger than the amount of the sedimentation liquid in the liquid mixture. However, when the amount of the sedimentation liquid is larger than the amount of the low-specific-gravity liquid in the liquid mixture, in contrast to the case of the above-described example, the rectification member is used as below.

[0042]

When the amount of the sedimentation liquid is larger than the amount of the low-specific-gravity liquid in the liquid mixture, the upstream rectification member 21 shown in FIG 2(A) and rotated by 180° is used as the upstream rectification member. That is, the member, in which the hole diameter of the penetration hole formed in the lower portion is larger than that of the penetration hole formed in the upper portion and the area of the portion (the lower region) provided with the penetration hole having a large hole diameter is narrower than that of the portion (the upper region) provided with the penetration hole having a small hole diameter, is used as the upstream rectification member.

Then, since the flow speed of the liquid mixture passing through the upper region may be suppressed, the difference in the flow rate of the liquid mixture within the cross-section of the liquid path lOh (that is, the difference in the flow rate of the liquid mixture within the cross-section of the liquid path lOh) at a position where the liquid mixture passes through the upstream rectification member may be decreased.

Furthermore, since the ratio of the low-specific-gravity liquid which passes through the lower portion of the upstream rectification member may be increased compared to the case where the upstream rectification member is provided with penetration holes having the same diameter, the mixing of the low-specific-gravity liquid and the sedimentation liquid in the liquid mixture between both rectification members is performed in a manner such that the low-specific-gravity liquid rises to a certain extent between the upstream rectification member and the downstream rectification member, and the difference in the mixture ratio between both liquids in the liquid mixture within the cross-section of the liquid path lOh may be decreased.

Accordingly, even when the amount of the sedimentation liquid is larger than the amount of the low-specific-gravity liquid, the difference in state (the flow rate, the mixture ratio, or the like) of the liquid mixture which has passed through the downstream rectification member within the cross-section of the liquid path lOh may be decreased.

[0043]

(Description of sedimentation member 23)

Further, as shown in FIG 1, the sedimentation member 23 is provided between the downstream rectification member 22 and the separation plate 1 Od. The

sedimentation member 23 is provided with plural penetration holes 23h which are formed along the direction of the body portion 11 of the main body portion 10. The plural penetration holes 23h are arranged so that the center axes are horizontal and the center axes are parallel to each other.

Further, each of the plural penetration holes 23h has a substantially square cross-sectional shape, and almost all penetration holes 23h are formed so as to have the same shape and the same cross-sectional area. Furthermore, as shown in FIG 2(C), the penetration hole 23h which is formed at a position where the sedimentation member 23 contacts the inner surface of the body portion 11 is formed so as to match the shape of the inner surface of the body portion 11.

[0044]

Since the sedimentation member 23 has the above-described configuration, the liquid mixture may be made to flow into the plural penetration holes 23h of the sedimentation member 23 in a region where the sedimentation member 23 is provided in the liquid path 1 Oh.

The liquid mixture which flows into the penetration hole 23h is separated into the sedimentation liquid and the low-specific-gravity liquid when passing through the penetration hole 23h. Specifically, the sedimentation liquid settles inside the penetration hole 23h of the sedimentation member 23, and the settling sedimentation liquid contacts and adheres to the inner surface of the penetration hole 23h, so that it is separated from the liquid mixture (that is, the low-specific-gravity liquid). At this time, since the cross-sectional area of the penetration hole 23h is small (the vertical length is short), the settling distance until the sedimentation liquid contacts the inner surface of the penetration hole 23h becomes shortened, and the time until the sedimentation liquid contacts the inner surface of the penetration hole 23h also becomes shortened.

Accordingly, when the above-described sedimentation member 23 is provided, the sedimentation liquid and the low-specific-gravity liquid may be rapidly and efficiently separated from each other.

[0045]

Then, the sedimentation liquid which adheres to the inner surface of the plural penetration holes 23h flows toward to the rear end of the sedimentation member 23 while being pressed by the liquid mixture flowing into the penetration hole 23h, and is discharged from the rear end of the sedimentation member 23. Then, the sedimentation liquid which is separated from the liquid mixture inside the penetration hole 23h of the sedimentation member 23 is discharged from the rear end of the sedimentation member 23, so that the sedimentation liquid settles to the lower portion of the liquid path lOh.

On the other hand, the liquid mixture from which the sedimentation liquid is separated flows out of the plural penetration holes 23h and flows upward in a pressed state in the direction opposite to that of the sedimentation liquid, so that the liquid mixture flows into the low-specific-gravity liquid discharge space through the

communication path lOf.

Accordingly, the sedimentation liquid which is discharged from the rear end of the sedimentation member 23 and settles toward the bottom portion of the liquid path lOh may be prevented from being mixed with the liquid mixture having a large content of low-specific-gravity liquid again. [0046]

Further, since the plural penetration holes 23h are formed so as to have the same cross-sectional shape and the same cross-sectional area, it is possible to decrease the difference in the flow resistance between the penetration holes 23h when the liquid mixture flows therethrough. Then, the liquid mixture may be made to almost uniformly flow into the plural penetration holes 23h of the sedimentation member 23. That is, since the flow rates of the liquid mixtures passing through the respective penetration holes 23h of the sedimentation member 23 may be made to be almost uniform, all the penetration holes 23h may be effectively used for the liquid separation, and the liquid separating efficiency of the device may be improved.

In particular, since the two rectification members 21 and 22 are provided, when the state of the liquid mixture supplied to the sedimentation member 23 is almost uniform within the cross-section of the liquid path lOh, the liquid separating efficiency of each penetration hole 23h may be made to be almost uniform in any penetration hole 23h, thereby further improving the liquid separating efficiency of the device.

[0047]

Furthermore, since the sedimentation member 23 is disposed so that the center axes of the plural penetration holes 23h are horizontal, the resistance in which the sedimentation liquid inside the penetration hole 23h is made to flow while being pressed by the liquid mixture decreases. Accordingly, the sedimentation liquid may be efficiently discharged from the inside of the plural penetration holes 23h, and both liquids separated once may be prevented from being mixed with each other again.

[0048]

Furthermore, with regard to the sedimentation member 23, the center axes of the plural penetration holes 23h may not be horizontal, and may not be inclined upward from the upstream side toward the downstream side when the sedimentation liquid is mixed in the low-specific-gravity liquid. For example, when the surface is inclined downward from the upstream side to the downstream side, the resistance in which the sedimentation liquid present on the inner surface of the penetration hole is made to flow by the liquid mixture may further decrease, thereby efficiently discharging the sedimentation liquid from the inside of the penetration hole 23h. Then, the liquid separating efficiency inside the penetration hole 23h of the sedimentation member 23 may be improved, and both liquids separated once may be prevented from being mixed with each other.

[0049]

(Method of forming sedimentation member 23)

The above-described sedimentation member 23 may be formed by any method, and the method is not particularly limited. For example, the sedimentation member 23 may be easily formed by arranging plural tubular members. In a case of forming the sedimentation member by arranging the plural tubular members, the tubular members having the same diameter are used. Accordingly, the sedimentation member 23 with the penetration holes 23h all having the same cross-sectional shape and the same

cross-sectional area may be simply and reliably formed.

[0050]

(Cross-sectional shape of penetration hole)

Furthermore, the cross-sectional shape of the penetration hole 23 h formed in the sedimentation member 23 is not limited to the above-described rectangular shape, and may be a circular shape, a triangular shape, or the like. That is, the cross-sectional shape is not particularly limited.

For example, in a case of a liquid mixture in which water (a sedimentation liquid) with high purity is mixed in a low-specific-gravity liquid such as oil, even when the water contacts the side surface of the penetration hole 23h, the water may be separated from the liquid mixture. In a case of treating such a liquid mixture, when the cross-section of the penetration hole 23h is formed in a rectangular shape which is elongated in the vertical direction so that the cross-sectional area increases, the water may adhere to the cross-sectional area thereof so as to be separated from the

low-specific-gravity liquid, thereby separating the water from the low-specific-gravity liquid with higher efficiency.

[0051]

(Description of inflow path 14)

Further, as shown in FIG 1 , the inflow path 14 is a tubular member which is disposed at the side surface of the body portion 11, and is disposed at the side of the front-end barrelhead 12 in relation to the two rectification members 21 and 22 in the front end of the body portion 11.

The front end of the inflow path 14 is closed, and the side surface of the front end thereof is provided with the supply port 14a. That is, the liquid mixture which is supplied from the base end of the inflow path 14 is supplied from the supply port 14a provided in the side surface of the front end into the body portion 11.

Furthermore, the supply port 14a is provided at the side surface near the front-end barrelhead 12, and the flowing direction of the liquid mixture supplied from the supply port 14a into the liquid path lOh is substantially parallel to the axial direction of the body portion 11.

[0052]

Since the inflow path 14 has the above-described structure, the liquid mixture is supplied from the supply port 14a of the inflow path 14 in the direction opposite to the direction where the liquid mixture flows inside the body portion 11 (in FIG. 1 , the direction from the left to the right, and hereinafter, referred to as a main direction), and collides with the inner surface of the front-end barrelhead 12. Then, since the liquid mixture which collides with the inner surface of the front-end barrelhead 12 first stays in the vicinity of the inner surface of the front-end barrelhead 12 and flows toward the main direction, the liquid mixture becomes a low-speed flow compared to the state where the liquid mixture is supplied from the supply port 14a of the inflow path 14 and flows inside the body portion 11 toward the rectification members 21 and 22.

Furthermore, with regard to the front-end barrelhead 12 with which the liquid mixture collides, since the inner surface thereof is formed in a substantially spherical shape, a flow of the liquid mixture is formed along the inner surface of the front-end barrelhead 12 when the liquid mixture collides with the inner surface of the front-end barrelhead 12. That is, the liquid mixture becomes a substantially radial flow which is formed along the inner surface of the front-end barrelhead 12 and has a small difference in speed at respective positions, and then the liquid mixture flows toward the main direction. Then, the flow of the liquid mixture becomes a flow which has a small difference in flow speed at respective positions within the cross-section of the body portion 11 until it reaches the rectification members 21 and 22.

That is, the flow speed of the liquid mixture may be made to have a small difference in flow speed at respective positions within the cross-section of the body portion until the liquid mixture reaches the rectification members 21 and 22.

[0053]

Furthermore, the position where the supply port 14a is formed in the side surface of the inflow path 14 is not particularly limited, but it is desirable that the supply port 14a be formed at the height of the free surface FS of the sedimentation liquid accumulated in the body portion 11. When the supply port 14a of the inflow path 14 is disposed at such a position, it is possible to prevent the sedimentation liquid accumulated in the body portion 11 from being stirred by the supplied liquid mixture when the liquid mixture is supplied from the supply port 14a of the inflow path 14 into the body portion 11. Then, since the sedimentation liquid accumulated in the body portion 11 may be prevented from being changed into liquid droplets and mixed with the low-specific-gravity liquid again (dispersed into the low-specific-gravity liquid again), the degradation of the liquid separating efficiency of the device may be suppressed when the sedimentation liquid accumulated in the body portion 11 and the low-specific-gravity liquid are mixed with each other again.

[0054]

Furthermore, even when the supply port 14a is formed at the height of the free surface FS, a part of the liquid mixture which is supplied from the supply port 14a into the body portion 11 collides with the inner surface of the front-end barrelhead 12, so that a phenomenon occurs in which the liquid mixture flows into the sedimentation liquid accumulated in the body portion 11. However, since the amount of the fluid mixture which flows into the sedimentation liquid accumulated in the body portion 11 is small and the speed is small, the sedimentation liquid is hardly mixed with the flowing liquid mixture.

Further, since the sedimentation liquid is accumulated in the bottom portion of the body portion 11 , most of the liquid mixture flows inside a space above the free interface FS of the sedimentation liquid. Accordingly, hereinafter, the "space above the free interface FS of the sedimentation liquid inside the body portion 11" is referred to as a "liquid path lOh", and the "cross-section of the space above the free interface FS of the sedimentation liquid inside the body portion 11" is referred to as a "cross-section of the liquid path 1 Oh". [0055]

(Process of separating liquid mixture using separator 1)

Next, the process of separating the liquid mixture using the separator 1 of the embodiment will be described.

First, a liquid mixture to be treated is supplied from the inflow path 14 into the body portion 11 of the main body portion 10. Then, the liquid mixture flows in the direction opposite to the main direction and collides with the inner surface of the front-end barrelhead 12. Then, the liquid mixture becomes a substantially radial flow along the inner surface of the front-end barrelhead 12 and flows toward the main direction. That is, the liquid mixture first flows toward the front-end barrelhead 12, and is reversed so as to flow from the front-end barrelhead 12 toward the rectification members 21 and 22. Then, during a time when the liquid mixture flows from the front-end barrelhead 12 to the upstream rectification member 21, the liquid mixture becomes a flow which has a substantially uniform flow speed within the cross-section of the liquid path 1 Oh.

[0056]

When the liquid mixture reaches the upstream rectification member 21, the liquid mixture passes through the penetration hole of the upstream rectification member 21. Since the liquid mixture is formed by dispersing the sedimentation liquid in the low-specific-gravity fluid, the flow speed of the liquid mixture which flows to the lower region 21B of the upstream rectification member 21 becomes faster.

On the other hand, since the penetration hole 21a formed in the upper region 21 A is larger than the penetration hole 21b formed in the lower region 2 IB, the resistance acting on the passage of the liquid mixture becomes larger at the lower portion of the upstream rectification member 21 than the upper portion thereof. Accordingly, since the flow speed of the liquid mixture passing through the lower region 21B may be suppressed, the difference in the flow speed within the cross-section of the liquid path lOh becomes smaller in the fluid mixture which has passed through the upstream rectification member 21.

[0057]

Furthermore, since the flow speed of the liquid mixture passing through the lower region 21B is suppressed, a comparatively large amount of sedimentation liquid which may easily pass through the lower region 21B of the upstream rectification member 21 may pass through the upper region 21 A. Then, since the sedimentation liquid which has passed through the upper region 21 A settles to a certain extent during a time when the liquid mixture which has passed through the upstream rectification member 21 flows to the downstream rectification member 22, the mixture of the low-specific-gravity liquid and the sedimentation liquid in the liquid mixture between the upstream rectification member 21 and the downstream rectification member 22 is promoted, and the difference in the mixture ratio of the liquid mixture within the cross-section of the liquid path lOh may be decreased.

[0058]

Then, since the fluid mixture which has passed through the upstream

rectification member 21 passes through the downstream rectification member 22 provided with the uniform penetration holes 22h, the flow speed within the cross-section of the liquid path lOh becomes further uniform.

[0059]

The liquid mixture which has passed through the downstream rectification member 22, that is, the fluid mixture of which the difference in the flow speed and the difference in the mixture ratio within the cross-section of the liquid path lOh decrease, passes through an area provided with the sedimentation member 23. At this time, since the sedimentation liquid contained in the liquid mixture settles and contacts the inner bottom surface of the penetration hole 23 h so as to adhere thereto during a time when the liquid mixture flows inside the penetration hole 23h of the sedimentation member 23 from the front end toward the rear end, the sedimentation liquid is separated from the liquid mixture. That is, the sedimentation liquid and the low-specific-gravity liquid are separated from each other in the penetration hole 23h.

[0060]

The separation of the sedimentation liquid and the low-specific-gravity liquid is performed while the liquid mixture passes through the penetration hole 23h, and the ratio of the sedimentation liquid dispersed in the low-specific-gravity liquid gradually decreases as the liquid mixture flows toward the rear end of the penetration hole 23h. Then, at the time when the liquid mixture is discharged from the rear end of the penetration hole 23h, the ratio of the sedimentation liquid dispersed in the

low-specific-gravity liquid is low, and the liquid mixture is almost completely separated into the low-specific-gravity liquid and the sedimentation liquid.

[0061]

Then, when the low-specific-gravity liquid reaches the separation plate lOd, the low-specific-gravity liquid flows into the low-specific-gravity liquid discharge space through the communication path lOf, and is discharged from low-specific-gravity liquid discharge path lib.

[0062]

On the other hand, the settling sedimentation liquid settles at the bottom portion of the liquid path 1 Oh so as to be accumulated therein, and is discharged to the outside through the sedimentation liquid discharge path 11a. Then, if a predetermined amount or more of the sedimentation liquid is accumulated when the accumulated sedimentation liquid is discharged from the sedimentation liquid discharge path 1 la, it is possible to prevent the low-specific-gravity liquid from being mixed with the sedimentation liquid again or prevent the low-specific-gravity liquid from flowing out of the sedimentation liquid discharge path 11a together with the sedimentation liquid.

[0063]

As described above, according to the separator 1 of the embodiment, it is possible to separate and collect the low-specific-gravity liquid and the sedimentation liquid by effectively separating the low-specific-gravity liquid and the sedimentation liquid contained in the liquid mixture.

[0064]

(Another example of inflow path 14)

Furthermore, in the above-described example, a case has been described in which the inflow path 14 is a tubular member disposed at the side surface of the body portion 11. However, as shown in FIG 3, the front-end barrelhead 12 may be equipped with a tubular member of which the axial direction is substantially parallel to the axial direction of the liquid path lOh and an angle formed between the axial direction thereof and the axial direction of the liquid path lOh becomes smaller, and this tubular member may be used as the inflow path.

In this case, it is desirable that a part of the upstream rectification member 21 be equipped with a region without a hole (hereinafter, referred to as a collision portion LF) (FIG 3(B)). Specifically, the collision portion LF is formed at a position where it intersects with the axial extension direction of the inflow path so that the area becomes larger than the cross-sectional area of the inflow path. Then, since most of the liquid mixture which flows through the inflow path from the outside collides with the collision portion LF of the upstream rectification member 21, the liquid mixture which reaches the sedimentation member 23 may be removed without any interference with the upstream rectification member 21 and the downstream rectification member 22. Accordingly, it is possible to maintain the function of decreasing the difference in the mixture ratio and the flow speed of the liquid mixture according to the respective positions within the cross-section of the liquid path lOh using the upstream rectification member 21 and the upstream rectification member 22.

[0065]

(Another example of sedimentation member 23)

Furthermore, in the above-described example, a case has been described in which the sedimentation member 23 includes plural penetration holes 23h. However, the sedimentation member may have a structure in which the liquid mixture may be separated into the low-specific-gravity liquid and the sedimentation liquid while the liquid mixture passes through the position of the sedimentation member, although the invention is not limited to the above-described structure. That is, a structure may be adopted in which the flow rate of the liquid mixture may be decreased somewhat and the sedimentation distance of the sedimentation liquid may be shortened when the liquid mixture passes through the position of the sedimentation member.

For example, as the sedimentation member, a sedimentation member which is formed by arranging plural plate-like members with a gap therebetween in the vertical direction may be used.

[Example 1]

[0066]

Next, a numerical simulation of the flow of the liquid mixture inside the liquid path and the water volume ratio in the liquid mixture was performed when the liquid mixture in which two types or more liquids with different specific gravities were mixed with each other were separated by the sedimentation type liquid-liquid separator.

[0067]

The numerical simulation was performed on the sedimentation type liquid-liquid separator of the invention having the structure of FIG 1 (Example) and the sedimentation type liquid-liquid separator having the structure of FIG 4 (Comparative example).

[0068]

The calculation was performed according to ANS YS CFX. The calculation condition is as below.

[0069]

(1) Liquid mixture

Liquid mixture: liquid mixture including oil (with density of 900 kg/m ³ and viscosity of 1.5 cP) and water (with density of 970 kg/m ³ and viscosity of 0.4 cP)

Flow rate of liquid mixture: 70 m ³ /h

Flow rate ratio: water:oil=l :2

Particle diameter of water: 180 um

[0070]

(2) Main body portion

Length of body portion (including barrelhead portion: 7600 mm

Length from inner surface of front-end barrelhead to separation plate: 6300 mm

Inner diameter: 1800 mm

Height of separation plate: 1550 mm

Diameter of inflow path: 300 mm

Furthermore, the side surface opening (only in Example) was formed by removing a portion with an axial length of 200 mm and a radial length of 100 mm (in the left-right direction of FIG. 1) in the side surface of the inflow path.

[0071]

(3) Rectification member

(i) Example

Upstream rectification member: upper region with opening rate of 30% and lower region with opening rate of 10%

Area ratio between upper region and lower region: upper region:lower region=l :5

Downstream rectification member: opening rate of 30%

(ii) Comparative example

Rectification member: opening rate of 30%

Furthermore, in the calculation, as the rectification member, the calculation was performed by installing an object having a pressure loss corresponding to the opening rate instead of the porous plate shown in FIGS. 2 and 4.

[0072]

(4) Sedimentation member

(i) Example

Cross-sectional shape of penetration hole: 80 mm x 80 mm

Length: 3000 mm

(ii) Comparative example

Length: 3000 mm

Distance between sedimentation members: 400 mm

[0073]

The result of the numerical simulation is shown in FIGS. 5 and 6.

Furthermore, in FIGS. 5(B) and 6(B), the dark colored region indicates a region where the water volume ratio is large.

[0074]

As shown in FIG 5(A), in Comparative example, since the size of penetration holes 121h of a rectification member 121 are all the same, it is found that the circulating flow directed from the vicinity of the inner surface of the body portion 111 toward the center of the body portion 111 is generated at the downstream side of the rectification member 121. Due to the influence of the circulating flow, there is a difference in flow speed of the liquid which flows through the sedimentation member 123 between the portion positioned near the center of the body portion 111 and the periphery thereof.

[0075]

On the other hand, as shown in FIG 6(A), in Example, the circulating flow is not generated at the downstream side of the downstream rectification member 22. Further, since the water flows so as to settle downward, the flow speed of the lower portion becomes faster than that of the other portions at the downstream side of the downstream rectification member 22, but the flow speed is almost the same and slow at the portion other than the lower portion. Then, even when the liquid mixture passes through the sedimentation member 23, the difference in the flow speed of the fluid mixture passing through the penetration holes 23h is small.

[0076]

As described above, in the separator of Example, it is found that the flow speed of the liquid mixture flowing inside the sedimentation member 23 may be almost uniform.

[0077]

Further, as shown in FIG. 5(B), in the separator of Comparative example, it is found that the water volume ratio smoothly changes from 0.25 to 0.05 and the water volume ratio gradually changes from the lower portion of the body portion 111 to the upper portion at the downstream side of the rectification member 121. That is, the difference in the water volume ratio at respective positions within the body portion 111 becomes larger at the downstream side of the rectification member 121.

[0078]

On the other hand, as shown in FIG 6(B), in the separator of Example, the water volume ratio changes within a narrow range of 0.25 to 0.05 at the downstream side of the downstream rectification member 22. That is, with regard to the water volume ratio inside the body portion 11 at the downstream side of the downstream rectification member 22, the difference in the water volume ratio at respective positions within the cross-section of the body portion 11 becomes smaller than that of the case of the separator of Comparative example except for the vicinity of the portion where water is accumulated.

[0079]

As described above, in the separator of Example, it is found that there is a small difference in the mixture ratio of the liquid mixture supplied to the sedimentation member 23 within the cross-section of the body portion 11.

[0080]

Then, when the water collection rates of the separator of Example and the separator of Comparative example are compared with each other, the water collection rate of the separator of Comparative example is about 0.86, and the water collection rate of the separator of Example is about 0.96. That is, it was proved that the water collection rate was largely improved, that is, oil and water were efficiently separated from each other by adopting the separator of Example. INDUSTRIAL APPLICABILITY

[0081]

The sedimentation type liquid-liquid separator of the invention is appropriate for separating a liquid mixture in a chemical plant, a treatment device, or the like, and is particularly appropriate as a separator in a facility that continuously performs a separation process.

REFERENCE SIGNS LIST

[0082]

1 : SEDIMENTATION TYPE LIQUID-LIQUID SEPARATOR

10: MAIN BODY PORTION

lOh: LIQUID PATH

11: BODY PORTION

11 a: LOW-SPECIFIC-GRAVITY LIQUID DISCHARGE PATH

lib: SEDIMENTATION LIQUID DISCHARGE PATH

14: INFLOW PATH

21 : UPSTREAM RECTIFICATION MEMBER

22: DOWNSTREAM RECTIFICATION MEMBER

23: SEDIMENTATION MEMBER

23h: PENETRATION HOLE

LF: COLLISION PORTION