Field of the art to which the invention refers [0001] Pyrolysis is the process of thermal degradation of long polymer chains into smaller, less complex chains. It is obtained by transferring heat to the prod uct for a defined time and at a defined pressure and temperature. The process requires residence times of the product to be processed which depend mainly on the temperature conditions and must be carried out with the no oxygen. The three major components obtained during pyrolysis are: oils, gas, ash containing impurities also including heavy metal residues and solid carbon black (also cal led respectively "char" and "coke"). Carbon black In turn is a valuable compo nent for the manufacturing industries, refineries and civil use. This invention has devised a special thermo-catalytic cracking plant which statistically depoly- merizes a large variety of plastics in a special way , by reducing them to oligo mers having a lower molecular weight for the most part in the liquid state and with a percentage in gaseous state. The final product is similar to liquid and gaseous fuels available on the market.

[0002] The proposed arrangement allows to obtain a fraction of liquid fuel oil, diesel and gasoline fuel oil and a mixed fraction of variable composition contain ing incondensable gas (methane) and liquefied gas (propane and butane). The liquid oils can be stored and used as a fuel in various applications (furnaces, boilers, turbines and diesel engines for thermal or electrical energy production) or in a mixture with rectified oils to obtain a product with lower impurities (e.g. sulfur content) even without the need for further treatments or refiner for the production of new raw material for the subsequent synthesis of the desired plas- tic, thus determining the virtuous closed cycle called "circular economy". Of par ticular interest it is possible to consider the use of the produced diesel and gasoline , which can be used in full or to cut the current fuels deriving from the refining processes, or they could constitute the total or partial alternative charge to the "virgin naphtha" used in "steam reforming" petrochemical processes suitable mainly for the production of olefinic monomers necessary to obtain the most common synthetic plastic polymers. Also in this case the so-called circular economy is implemented but with cycles which can be repeated in a theoreti cally unlimited number of times.

[0003] The production mix is strongly influenced by the type of processed plas- tics and by the operating conditions of the plant (temperature, pressure, resi dence time, type of reactor and any type of catalyst used). This is why a versati le system has been designed to adapt the key operating parameters for this purpose with optimized operating conditions and also dependant on the type of plastics to be treated. State of pre-existing technique Status quo

[0004] The present invention, identified in the present description by letter A, constitutes an improvement of the Italian patent presented in September 2018 by the same holder of this proposal with the title: "Thermal-catalytic pyrolysis plant for the production of fuel oil from recycled plastics obtained by a continu ous high pressure process". The above mentioned patent, approved in August 2020, was registered with the number 102018000008377 and will be marked in this description for convenience with the letter B.

[0005] For the comparisons made at the time with the patents marked: D1 : WO 2009/095888, D2: EP 3 029 094, D3: US 2007/0173673, D4: US 2013/0136665, D5: WO 2010/070689, D6: US 2002/0086910, reference is made to the description of patent B in the documentation filed in its time in paragraph "1.3.2 State of the pre-existing technique":

In summary, the invention is characterized and confirms by the following gen eral characteristics which constitute strengths already mentioned in patent B or improved according to the description of the preceding paragraph 1 .3.2 and which will be summarized hereinafter:

1. It is a process which does not require combustion with pure oxygen or with that of the air for the destruction of the substance to be treated as occurs in thermovalorizers in which carbon dioxide is inevitably produced.

2. It is a process that values rejection and allows the realization of the so-called circular economy.

3. It is a “steady state” process that allows a treatment of higher quantities of waste than “batch” processes.

4. The plant is able to neutralize with scrubbing and cooling systems consisting of concentrated strong bases solutions dedicated for each stream, potential acid products deriving mainly from plastics with the presence of chlorine in the molecule.

Characteristics of the new proposal A compared with B [0006] The new proposal A concerns a plant characterized by solutions already identified in proposal B which have been partially modified or integrated with fur ther expedients so as to achieve in general improvements in the plant perfor mance and extensions of the operating limits of the process. The following most important key parameters have been addressed: a) Plastics mixing temperature to be treated in R101 : The melting temperature of some plastics requires operating values significantly higher than about 280 °C already in the mixing phase in the first reactor to allow the fluid to be pumpable to the train of the reactors receiving the product to be processed. It is generally necessary to have temperatures higher than about 400 °C to ensure adequate softening of all types of plastics and to feed to the subse quent reactors a fluid mass with a relative low viscosity in which the actual thermo-catalytic cracking takes place. The operating temperature limit in pro posal B in R101 was given by the maximum design temperature of the stirrer seal. The seals of the mechanical stirring members, suitable for the type of critical operation requiring high safety standards, have an operating limit of about 280 ° C, it is therefore necessary to ensure the mixing of the product in an alternative manner if it is desired to exceed this limit. This is done with the proposal A by recycling the process fluid leaving the last reactor back onto the first R101 reactor with considerably greater flow rates than that of the production capacity and variations depending on the type of plastic to be treated. b) Reactor configuration : The positive effect induced by the increased and more fluid hydraulic load is also that of guaranteeing a better heat exchange capacity to the reactors that has also been possible for this modification (see attached sheets 4A and 4B) making them function as a PFR (plug flow reac tor) unit instead of CSTR (continuous stirred tank reactor) as in case B. c) operation bleeds for the elimination of impurities and carbon black: The man agement of the elimination of impurities and carbon black in proposal B re- quires a relatively higher product waste if compared with A. The integrative interventions have allowed a management of the separation of high boiling products and carbon black better and allowed greater yields by introducing more selective separation systems and improved operational management introduced in points of the plant in which the temperature is relatively high and allows the separated product a rheology compatible with the emptying requirements of the apparatus (in in this case a filter) designed for its sepa ration. d) production diversification : production diversification has also been carried out to avoid the insertion downstream of the plant of further distillation sys- terns necessary in the event of a request for a better exploitation of produc tions and of possibilities of commercial diversification. e) materials corrosion : the proposed system has been improved and integrated in anticorrosive function with a new prevention systems (insertion of sacrifi cial anodes) which have been added to the neutralization system (concen- trated solution of strong bases such as caustic soda) already present in the proposal B. f) Catalyst life cycle: in proposal A a catalyst regeneration system has been created which avoids removal because it operates within the reactor. The catalyst is positioned so as to have a greater contact surface with the product in order to maximize its catalytic activity.

Detailed description of the invention and its competitive characterization. [0007] The implementation of the above considerations listed in paragraph

1.3.2.2. has led to the following plant integrations consisting both in a new rede sign of the characteristics of the equipment and in a change in the operating modes with respect to case B:

Plant integrations [0008] 1) R101 digester reactor characteristics: (see also attached sheet No. 1 for the whole treatment unless otherwise specified). The R101 reactor re ceives the raw material in the solid state; it must be ensured that the melting of the introduced plastic and its homogenization in the mass takes place therein . It is necessary to have a suitable temperature and mixing. In turn, the two fac- tors complement each other. The more effective the mixing is achieved, the more effective operations with a high temperature fluid which gets low viscosity and high heat exchange and the more the recycle mass at higher temperature is such as to guarantee a hydraulic replacement inside the reactor and the more is proportionally greater than the quantity of plastic intake to be treated. With the new proposal A, for the same production capacity, it is possible to have operating temperatures of about 100 - 150 ° C higher than the maximum fore seen and achievable with respect to the case of the patent B in which the recy cling of the finished product, although possible, it takes place at very lower temperatures because it is taken from the cooled product and has the sole pur- pose of ensuring in R101an adequate fluidization of the reagent mass only if it is necessary for unforeseen factors such as for example those of the introduc tion of particularly critical plastic mixtures or of raw material loads inserted into the reactor with an abnormally higher frequency. Recycling R is provided in B for a batch use or for filling the reactor in the start-up phases (see sheet 1 bis - recycling is indicated with the letter R -). In case A, recycling therefore , the stir rer is replaced in its entirely and has a dual purpose: to ensure mixing and to ensure the required thermal supply . The RE 101 electric bundle heat ex- changer (see attached sheet n ° 2) is used only in start-up transients or in cases of extra energy demand for possible tip thermal loads. Recycling is continuous and regulated according to the required R101 temperature. In the configuration provided by B, the mixing of the product is guaranteed by mechanical agitation (flow- through or magnetic drive) which however allows lower temperature val ues because they must be compatible with the maximum values guaranteed by the best mechanical seals technology available on the market today .

Seals other than those mentioned ( for example those with nitrogen-fluxed laby rinths) would be excluded both for safety reasons and practical functionality. The R101 reactor, which operates at considerably high temperatures, with re spect to the external environment , it would not have a multiple level of protec tion deriving from overlapping containers typical of the aforementioned seals and in any case considerable plant complications would be required because either of the compression and intercooling systems would be necessary in the case of the fluxed mechanical seals or magnetic drive. However, such refrig eration systems would in any case be of limited capacity , since the exchange surface in direct contact with the members to be cooled is insufficient with re spect to the need for heat exchange and the whole would also affect the relia bility of the plant . If the recycling does not have a temperature control system, realized instead with the introduction of the exchanger E003 with the proposal A, it would be possible to have a temperature value in R101 higher than the maximum allowed by the technology of the transfer pump G001 . Therefore, the integration provided by A allows an operating temperature in R101 that is ap proximately 80 - 150 ° C with respect to the maximum allowed by the patent B. With proposal A it is also possible to operate, as a corollary to the described in tegration, with a R101 reactor much more simplified than the proposal B (see attached sheets 2 for case A and 2bis for case B in which the two units relating to case A and B are compared) without any stirring device.

2) Characteristics of the other RNi pyrolysis reactors (see also sheet n ° 4A, n ° 4B attached and n ° 4C referring to the proposal made in B). As a further con sequence of the additions described in 1), there are the following advantages and the integration realized also for the other reactor units: a) The new units, always arranged in series, but constructively very simplified and suitably modified, guarantee in this case a flow more responsive to that of the piston type ("plug flow") compared to the previous configuration in B. The “Plug flow” configuration requires, under equal conditions, smaller re- action volumes or with equal volumes, greater capacity. b) being the feed rates to RNi increased as a multiple of the production capaci ty, the apparatus have in fact a higher heat exchange coefficient and this re quires smaller exchange surfaces ,with the same conditions. c) The reactors of the RNi type proposal A are more compact than the reactors of B (see attached sheet n ° 4C relating to proposal B for comparison with 4A and 4B relating to proposal A), they therefore allow higher operating pres sures with the same conditions and include a multi-fold in -situ catalyst re generation system without the need for removal of the exhausted material from the equipment. In this way, the maintenance and replacement costs of the catalyst are drastically reduced. d) a system for the management and disposal of impurities ( mainly constituted by foreign materials present in the plastic packages to be treated) has been introduced and of the carbon black produced continuously and such as to avoid stopping the plant replacing the timed bleed of proposal B e) It has been envisaged to improve the protection against corrosion of the equipment by providing it with a cathodic protection system by inserting an aluminium sacrificial anode suitably installed in R101 (instead of the catalyst housing in proposal B, see sheet n ° 2) and/or installed in the other reactors within one or more tubes made blind for the introduction of the material (see attached sheets No. 4 ° or 4B - letter P). The integration is able to minimize the corrosive phenomena that the presence of heterogeneous plastics to be processed having heteroatoms in their molecular structure (in particular those related to chlorine) inevitably entails. f) A greater diversification of the final products is achieved which would have been obtained with B only with the addition of a distillation unit which should have processed the oil obtained, otherwise usable only as fuel oil or as cut ting oil for heavy diesel fuel . g) Significant energy recoveries have been introduced through heat exchangers E002, E003, E004, E005, some of which (E003, E004) have the main func tion of rapidly cooling ("quencing") the process fluid leaving the reactor train. The steam produced at high and medium pressure can be used in the pro duction of electricity or for internal uses as heating fluid. h) The frusto-conical shape of the bottom provided by the proposal B (see sheet n ° 2 B and 4C attached for comparison), realized to facilitate the dep osition and subsequent cleaning with extraction of the carbon black or high- boiling solid products with high molecular weight, it is no longer necessary with proposal A as well as the external half-tubes which had to guarantee thermal uniformity inside the reactors. The existence of a recycling at a high er temperature that gives the thermal duty to R101 required by the process improves the fluidity of the product and in fact eliminates the problem of car rying out a heat transfer with minimization of the thermal gradient inside the reactor in the radial direction which would be the case of use of the heating element placed in a central position which radiates the heat towards the pe riphery. In this case (case A) the heat supply due to recycling take place by direct contact of the fluids. i) The continuous or timed bleeds with timed valve E2 provided in B to extract the sludge (slurry) (see sheet n ° 1 bis) are replaced in A with a filter capable of separating the solid from the liquid and discharging a much more concen trated sludge ( slurry ) by sending it into a suitable closed-loop container for disposal. The frequency is determined as a function of the pressure drop of the filter which increases over time as the deposited solid phase increases to a maximum allowable amount and such as to require the discharge of the cake formed in the filtering surface.

Competitive Advantages

[0009] In summary: It is proposed with A a process which can treat mixed ) plastics (heterogeneous ) with a high level of difficulty in processability , thanks to the possibility of realizing :

1) high temperatures (higher than B). a) the proposal A allows allows to process plastics which need to have tempera- tures higher than 400 ° C, a value in fact higher than that obtainable in the proposal B. An adequate thermal level is necessary to achieve the melting of some of the most critical plastics certainly present in the heterogeneous ones (see also table n ° 2 below). The mechanical stirrer can also be elimi- nated in R101 in view of the introduction of a suitable recycle which guaran tees an adequate replacement on the first reactor R101 , causing an equiva lent mixing. The new operating configuration provides for higher reaction temperatures as a whole which adequately compensate for shorter resi dence times, under equal conditions, determined by the hydraulic load of the recycling of the product which impacts on the whole reactor train . b) Proposal A has a production capacity which is greater than under the same conditions with respect to B and other types of D taken as reference. A tem perature deviation in R101 of about 50% upwards (for example from about 280 ° C to about 420 ° C), in addition to allowing all types of plastics to be processed, the kinetic speed in the next train of reactors increases by about one hundred times and therefore such a condition determines, under the same conditions, despite the increase in the hydraulic load due to recycling (which reduces the residence time but increases the heat exchange coeffi cient) a significant reduction in the overall dimensions of the equipment, since the whole results in having equipment with smaller volumes and sur faces equal to other conditions. In the table n ° 1 below there are for many plastics the degradation temperature values. For many types there are val ues significantly higher than 300 ° C.

Table n° 1 - Common plastics thermal degradation temperature - c) The temperature increase made possible and expected in about 120-150 ° C with respect to B, necessary to process some types of plastics, would tend to worsen, with the same conditions , an increase in the double bonds (see graph no. 1 attached in the drawings) but is largely compensated by the ex ponential decrease of the residence time, the kinetics being increased by about two orders of magnitude corresponding to an equivalent decrease in reaction volumes with the same other conditions.

2) High pressures (higher than B) a) the high pressures produce a higher liquid oil yield and a lower coke amount (carbon black) under the same conditions . In practice, low pressures favor cracking in the terminal part of the polymer chains while the high ones favor it in the central part. This allows within certain limits to orient the cleavage of the polymer chains making them statistically shorter and therefore to realize a product comparable to a fuel oil that is Theologically better at lower viscosi ty and more fluid. There is therefore a proportion of low-boiling products which are proportionally higher than condensed selectively condensed con tribute to increasing diesel and petrol at the detriment of fuel oil. The inser- tion of additional modification of the proposal B allows selective production without the need for downstream insertion of the system of more impactant integration such as those of the distillation columns (as also happens in pa tent D1 and also in D2 already discussed in its time with the proposal B) (see also graphics n ° 2A and 2B in the attached drawings). The proposal A confirms what is already in B but allows an increase in the maximum operat ing pressure limit as a consequence of a smaller size due to the greater compactness of the reactors with the same other conditions. b) the high pressures decrease the formation of double bonds (diolefins) and then coke. The low pressures, as already said , favor cracking in the terminal part of the paraffinic chains, with formation of methane and ethane, while the high ones favor it in the central part. The formation of diolefins is favored by the cracking of the terminal part of the polymer chains and, due to their reac tivity, leads to the reaction conditions to tar and coke. As in all pyrolytic pro- cesses, it is inevitable that over time carbonaceous substances are formed which deposit on the catalyst, deactivating it. Higher pressures than atmos pheric pressure result in a longer catalysts life because they reduce the formation of this type of by-products. In fact, their formation is minimized be cause the dehydrogenations , which take place with an increase in the num- ber of moles, contrasted by an increase in operating pressure (see also graph No. 1 and graph No. 3 attached in the drawings) are reduced . c) since the gas is intimately distributed in the liquid phase inside the reactors but with the A it is possible to operate under equal conditions at even greater pressures given the structural characteristics of the reactors which has been simplified and reduced in overall dimensions . A table is reported below (table n ° 2) comparison of yield on a mixture of municipal plastics in which the much higher values obtained with operating pressure conditions from 3.1 to 16 absolute bar are raised compared to the productions obtained at atmos pheric pressure which also contain a much higher percentage of by-products.

Table n° 2 municipal plastic thermal pyrolysis yields

3) a system for the removal of chlorides (as in B but diversified by production flow - see sheet n ° 1 attached in drawings -)

4) a system for the separation of the high boiling compared to the total production (absent in B). It is obtained on the basis of transfers from R101 to D104 with a frequency determined by the chemical - physical and rheological characteristics of the product which in time increases its high boiling fraction which ac- cumulate and are purged according to a pattern described by graph n ° 5 in the accompanying drawings . The purged fraction can be likened as a characteristic to that of a fuel oil.

5) a production capacity greater than B, other conditions being equal, linked to the possibility of regenerating of online catalysts , absent in B. With the intro- duction in proposal A of an "on line" regeneration system, whose cycle time is much shorter than what is necessary for the removal of the catalyst from the reactors, the "off site" regeneration and its subsequent re-insertion , the number of hours / year of travel of the reactors and therefore of the plant is considerably increased . 6) an impurity elimination system with a higher yield than in B by the insertion of filters F100 and F101 (see sheet No. 1 attached in the drawings).

7) a production capacity greater than B with the same other conditions due to the increased degree of conversion due to the fact that the new reactor units, always arranged in series, but constructively very simplified and suitably modi- fied, in this case they guarantee a flow more responsive to that of the piston type ("plug flow") with respect to the previous configuration in B in which, for example, there were no baffles which oriented the flow or tubes through which the flow passed, and there was no absolute guarantee of turbulent regime due to the hydraulic flow rates of much lower.

[0010] The "plug flow" configuration requires, under the same conditions, small- er reaction volumes or, with the same volumes, greater capacities. Since the supply flow rates to RNi are increased and a multiple of the production capaci ty, the apparatuses have in fact a higher heat exchange coefficient and this re quires smaller exchange surfaces with the same conditions. The reactors of proposal A of the RNi type are more compact than reactors of B (see sheet n ° 4C attached in the drawings relating to proposal B for comparison with 4A and 4B relating to proposal A), they therefore allow higher operating pressures with the same conditions and include a multi-fold in-situ catalyst regeneration sys tem without the need for removal of the exhausted material from the equip ment. In this way, the maintenance and replacement costs of the catalyst are drastically reduced. With proposal A, as regards the reactor train following R101 , given the general rise in the thermal profile and an increased hydraulic load due to the recycling of the reacted product, it is possible, having relatively high speeds and in general a fluid dynamic condition of turbulent regime , to provide a “piston” flow condition inside the reactors (plug flow). All this results in an increase in load all other conditions being equal. For a comparison be tween an arrangement with plug flow reactors and CSTR see also graph n ° 4 below. This is a reagent process fluid with a piston mechanism ("plug flow re actor" - PFR) which, with respect to the cascade-mixed of proposal B, re quires, under the same conditions and, depending on the conversion degree ZR, smaller reaction volumes (see also chart n ° 4 attached in the drawings for a comparison). The pipes in which the catalyst is inserted are designed to en sure a turbulent flow and also simulate the type of plug flow reactor.

[0011]

8) the special type of hollow baffle arranged axially with a self-supporting struc- ture installed inside it at R101 (see also sheet n ° 2 in the annex) indicated by the letter S, which contained in proposal B the catalyst in granular form, it is proposed in A but it is used for the insertion inside it of a metal bar of suitable material which follows in the electrochemical scale of the elements the material with which the apparatuses are made (see also sheets n ° 2, 4A and 4B at tached with the reference P). It is installed in such a way that there is physical continuity between the two different materials and the protection of the entire plant structure is ensured (see also figure n ° 1 attached in the drawings). The sacrificial bar will reduce its size over time and can be checked periodically to estimate the corrosion rate and to be able to plan its replacement with mainte nance interventions.

Detailed description of operating sequences (see sheet n ° 1 attached in the drawings)

[0012] an overall diagram of the arrangement of the plant units is reported ac cording to the “steady state” production mode with flow from left to right and ob tained with reactors arranged in cascade but operation comparable to plug flow reactors (PFR = plug flow reactor). The detailed representation of the individual units is delegated to other attachments. The reactors R101 and RNi in which the catalyst is installed are shown, an operating description which includes the regeneration cycle of the catalyst is given below. Regeneration involves a) a step of emptying most of the liquid product not completely adsorbed by the cat alyst. Stripping is achieved with nitrogen heated by E006 to about 180 - 200 ° C using part of the high pressure steam obtained from the various energy recover ies of the process in E003 and E004 b) a high pressure steam stripping step at about 180 -250 ° C of the organic residue intimately adsorbed in the catalyst. The steam is obtained from an energy recovery of the plant c) a step of remov ing residual coke particles obtained with hot air at about 180-250 ° C heated with high pressure steam (also obtained from the process) by means of E001 which is sent to the column causes self-combustion d) a final phase of elimina tion of air with hot nitrogen fluxing obtained with repetition of the alignment a). The gaseous flows and the combustion fumes of the various phases are con veyed to the final treatment T. The valve alignment for the RN unit in regenera- tion is as follows (see sheet 4 A): 17 and 20 closed; opened in sequence: 12 open, 28 open with 12 closed, 12 open with 28 closed, 13 open with 12 closed, 12 open with 13 closed, 12 closed. [0013] The pedicle-signed reactor units can vary between 1 and n since n be ing n an integer which can vary between 2 and 50. They are of the type sche matized in the attached sheet 4A or 4B. The final accumulators of liquid prod uct (feedstock) are D101 (storage product based on gasoline with included aqueous solution of 50% by weight caustic soda to neutralize the presence of chlorinated products), D102 (storage of diesel-based product with included aqueous solution of 50% by weight caustic soda to neutralize the presence of chlorinated products), D104 (storage of combustible oil product with included aqueous solution of 50% by weight caustic soda to neutralize the presence of chlorinated products), D103 gas / liquid separator product at the outlet of the reactor train. The pump G001 , equipped in delivery with filter F101 , has the function of transferring the product from the first to the second reactor unit. The product output from the last reactor is sent, after cooling in E003, to the liquid gas separator D103 after partial depressurization obtained with the regulation valve 9 which causes a flash of the inlet product which produces a biphasic flow. The liquid phase is recycled in R101 while the gaseous phase , after rapid quench by E004, is partially condensed into D102, and the residual gas phase of lower boiling products is sent through the control valve 24, in D101 where it undergoes a further cooling and condensation. In D101 the pressure regulat- ing valve 26, kept at about atmospheric values, allows the outlet of gaseous not condensable products sent for final use. The pumps G002, G004 and G006 pick up the final liquid products from the respective accumulators D102, D101 and D104 and send them to their final destination when the maximum expected levels of the corresponding tanks are reached. In D101 , D102 and D104 there are two communicating environments divided by a weir inside the tanks / de canters. The organic phase coming from the gas phase in the case of D101 and D102 comes into contact and condensed by the aqueous soda solution which, over time, with a rate depending on the quantity of chlorides to be neu tralized, is salified and is replaced with another fresh one. The organic conden- sate purified from chlorides, with a lower density, is stratified in the upper part of the liquid head and overflows once it reaches the maximum height of the weir in the adjacent environment in which the organic phase is accumulated. The three units D101 , D102 and D104 are mantained at a predetermined tempera ture by recycling the aqueous solution of soda by cooling D101 with E104, D104 with E005. The flow arriving at D102 is cooled on line with E004. The delivery of the saturated chloride product or solution is cooled by E002 during the trans- fer to final destination. On all units D101 , D102 and D104 there is provided a caustic soda connection which provides for regenerates the sodium solution when requested . On the delivery of G001 and G006 are installed the respective filters F101 and F100 which retain the impurities present in the plastic (non plastic materials, traces of non-ferrous heavy metals, etc.) and part of the fatal carbon black which is produced.

[0014] As regards the loading of the raw material R in R101 , two capacitive units are schematized with the initials X101 and X102 with X102 having a vol ume slightly greater than X101 and the on-off valves are numbered so that the understanding of their sequential operation is helped . In the discharge phase produced by X101 to X102, the valves 1 and 4 are open, the valves 2, 3 and 5 are closed. The G005 fan sucks in and creates a slight vacuum within X102 to assist the discharge from X101. In the subsequent inerting step the valves 1 , 3 and 5 are kept closed, the 2 and 4 are opened. A flow of nitrogen is introduced through the valve 2 open and under pressure control, kept at values higher than atmospheric pressure, in X102 and sucked by the pump G005 at the out let at X102 so as to make the internal environment free of air. In the subse quent phase of discharge to the reactor R101 , the 2 and 3 are open, the 1 , 4 and 5 are closed and G005 is stopped. The nitrogen entering X102 at a higher pressure than that of R101 , facilitates the unloading of the plastic and makes it total. It also creates on the top of R101 an inertised environment free of air and therefore oxygen. The subsequent depressurization step provides only 4 and 2 open and is obtained by restarting the fan G005 and following the closure of the 2. In this way a slight depression is generated which will facilitate the sub sequent unloading step between X101 and X102. The loading step X101 pro- vides only the opening of the 5.

[0015] The reactor R101 is provided with an autonomous continuous padding with nitrogen. The padding mechanism (inertization) occurs with a split range valve clearance located upstream (in gas inlet mode) and downstream (in gas ejection mode) of the point to be inertized. If the pressure drops the upstream valve 6 will tend to open and the downstream valve 7 will close and vice versa. A "spread" (a tolerance) of an acceptable value with respect to the set value (slightly higher than atmospheric pressure) is established , so that, for a given operating condition, both valves are in the closed position with evident reduction of nitrogen required. The maintenance of pressure values of little or much higher than atmospheric also guarantees the absence of air infiltrations and therefore oxygen. [0016] The reactors which receive the product from the pump G001 in fact also become heat exchangers , since they can be constituted by a tube - bundle electrical resistance or alternatively a tube-bundle with tube-side heating fluid. The process fluid passes through both the partitions on the shell side and the pipes filled with catalyst side . A compact heat exchange unit is provided with high efficiency and maintenance is relatively simple to provide, both the tube bundle of the central heat exchanger and the tube bundle of the reactor being removable with respect to the outer surface so that cleaning can be carried out more easily extraordinary maintenance when needed.

Description of the attached sheets and graphs in the attached document “draw- inas”

[0017] Attached Sheet No. 1 : the plastic treatment plant in the process part ex cluding utilities is simplified - see for the description section 1.3.3.1. The equipment is marked with the following symbology : R: reactor, D: tank, G: pump, F: filter, E: heat exchanger, X: special hopper . For the description of the detailed symbology see attached sheet n° 3 and sheet 3 n° bis.

Attached sheet n ° 1 bis

[0018] The simplified flow sheet filed for patent B for comparison with sheet n ° 1 is reported .

Attached sheet n ° 2 [0019] This is a simplified diagram of the reactor R101 according to the new proposal A. The letters indicate the inlet and outlet nozzles of the apparatus so as to simplify the understanding of its functionality. Furthermore, the elements characterizing the unit are indicated with an item : R101 is the item of the unit as a whole, RE101 the exchange unit (in this case electrical, in fact used only for the starting transients being kept at a temperature set value guaranteed by the recycling coming from D103 (see sheet n ° 1). The letters of the nozzles in- dicate the following: A: product inlet B: safety device / nitrogen padding. W1 / W2: load cells. E: process fluid outlet . C: instrument panel connection. D: re cycling from D103, F: recycling inlet. Q: sacrificial anode housing S: sacrificial anode. RE: electric resistance exchanger

[0020] Attached sheet N ° 2B - a simplified diagram of the reactor filed with proposal B is shown in order to have the possibility of a quick comparison with the attached sheet N ° 2.

This is the unit R101 provided with stirrer and heating elements. The letters in dicate the inlet and outlet nozzles of the apparatus so as to simplify the un derstanding of its functionality. Furthermore, the elements characterizing the unit are indicated with an item : R101 is the item of the unit as a whole, A101 is the stirrer , RE101 is the exchanging unit (in this case electric) equipped with dome E101 (of which a more detailed description is given in sheet 4). The let ters of the nozzles indicate the following: A: liquid product and / or gas product outlet B: gas inlet / outlet. W: load cells D: inlet / outlet of heating fluid. C: pro- cess fluid inlet / outlet. E: carbon black drain / bleed. P: Diathermic fluid inlet / outlet. F: instrumentation installation. N: nitrogen inlet / outlet. Q: baffle . S: catalyst housing. The scheme also provides that the reactor is equipped with a given number of external half-tube coils welded on the cylindrical part of the unit for the purpose of heat transfer. [0021 ] Attachment sheet n ° 3

Shows an explanatory legend of the symbols used in all other attachments [0022] sheet n ° 3 bis

Shows an explanatory legend of the function of the equipment with items used in sheet n ° 1 . A: air, B: fraction similar to petrol, C: industrial water, D: fraction similar to diesel oil, G: gaseous fraction similar to combustible gas, NaOFI: caustic soda solution at 50% by weight for abatement of chlorinated species, N: nitrogen, O: fraction similar to high boiling fuel oil with no sulfur content, R: raw material to be processed (plastic in granules), S: waste solid based on ash and carbon black, T: gaseous flow sent to the final abatement treatment, V1 : high pressure steam, V2: medium pressure steam, W: chlorinated water with final treatment. [0023] Attachment sheet N ° 4A and N ° 4B: a simplified scheme of the reac tor type RNi is reported . It is not equipped with a stirrer . The exchanger RENi can be electric (sheet 4B) or have a heating fluid shown (sheet 4A) in this case in the through - drawing on the tube side and without the shell coming into di rect contact with the process fluid. The sheet 4A has a central exchanger with inlet and outlet of heating fluid (letters H). The sheet 4B schematises a use beam exchanger of electrical resistance (RE). The fluid enters B, passes trough the reactor baffles from the bottom to the top, falls back from the bottom and flows through the pipes with (or without) catalyst (indicated with D). One or more tubes may have the insertion of a sacrificial anode (P). The description is completed by the indication of: product outlet nozzles C, for the safety ele ments (S), for the padding and the instrumentation (E).

[0024] Attachment sheet N ° 4C: a simplified scheme of the RNi type reactor filed in proposal B is reported for comparison with schemes 4A and 4B.

[0025] Annex graphic n ° 1 : a graph is shown in which the rate of formation of double bonds as a function of temperature and pressure . is correlated.

[0026] Annex graphic n ° 2A and n ° 2B: the distribution of the pyrolyzed frac tions obtained as a function of pressure and for two different temperatures is displayed .

[0027] Annex graphic No. 3: the amount of coke deposited on the catalyst is correlated as a function of the partial pressure of hydrogen which is different and as a function of the operating pressure of the system.

[0028] Annex graphic No. 4: related a ratio a between volumes of two different reactor units (PFR and CSTR) for a kinetics of the first order as a function of the degree of conversion and varying the number of reactors in the case of the CSTR attitude .

[0029] Annex graphic No. 5: The variation in the volume of the plastic filler reactor as a function of the number of running cycles is correlated . [0030] Annex figure n ° 1 : the positioning of various chemical elements accord ing to their electrochemical potential is shown .

Detailed description of the operation of the invention by means of the operat ing sequences.

[0031] A description of the operating modes of the plant in the case of a multi stage configuration with units as described above, operating in cascade and in a steady state cycle, is given below . See also, unless otherwise specified, the attached schematic sheet No. 1 to which the whole description refers and for technical details relating to the limit values of the operating conditions, refer ence is made to the claims.

1. The recycled plastic material previously chopped into flakes / pellets will be introduced into the hopper X101 by means of a metering device and then transferred into the reactor R101 , filled with nitrogen and in an atmosphere analyzed to ensure total absence of oxygen, an approximately constant quantity bounded by the section of pipe intercepted by two valves which open alternately. There is also on the top of the tube a nitrogen connection which is opened to facilitate the evacuation of the product inside the reactor. It is assumed that the system is already operating and has oil inside the reactor already produced previously so as to be referred to in the description at an attitude already in steady state conditions. The quantity of plastic introduced is in an adequate percentage and the entry is carried out with a constant frequency . The volume of liquid existing in R101 is adequately monitored by the redundant load cells W1 and W2 and having multiple elements or an equivalent level measurement system. There is also a constant detection of the absorption of the transfer pump G001 which also gives an indirect indica tion of the level of homogenization of the solid - liquid mixture. The tempera ture of R101 is kept constant and at a predetermined value by regulating the heat exchange of the output flow of E003 . The regulating valve 10 ensures that the R101 level is kept constant. The electrical resistance installed in R101 (see sheet n ° 2) has the main purpose of bringing the reactor content during the starting phase to a suitable temperature so that it has an ade quate fluidity so that it can be transferred via G001 to the reactor train RN. 2. The flow to be processed passes through the second unit RN1 with catalyst in which it is further heated and any subsequent ones provided for by the plant all heated by an appropriate fluid or by a tube bundle electrical re sistance as illustrated in sheets 4A and 4B. The flow leaving the last reactor is cooled in E003 to a value compatible with the requirements of the process and by means of the pressure regulator valve 9 is sent to the gas / liquid separator in which there is a flash. The pressure of D103 is regulated by valve 24 placed at the outlet of D102 and the liquid head in D103 is guaran teed by valve 8. The gaseous flow leaving D103 is significantly cooled in E004 and sent in a mixed phase into D102 in which it comes into contact with the aqueous solution of concentrated caustic soda for its purification from chlorides. The condensed liquid constitutes a fraction of medium boiling equivalent to the diesel fuel which will be transferred to final use after cooling with E002 once the D102 level has reached its maximum allowed level . The fraction of uncondensed gas at the conditions of temperature ( about 150 to 200 ° C ) and pressure (about 1.5 to 5 bar ) D102 is sent via the valve 24 in D101 where a hydrocarbon fraction with characteristics equivalent to those of the gasoline is cooled and condensed . The remaining uncondensed part, which constitutes hydrogen, methane gas and LPG, is sent to final use by means of the valve 26 which operates maintaining in D101 a pressure slightly higher than atmospheric pressure . The liquid content of D103 constitutes the highest boil ing fraction of the charge which undergoes, once transferred to R101 , a further partial evaporation of low boiling points products which will also be cooled and condensed in D101 by means of the vent line , the pressure of which is regu- lated by the valve 7.

[0032] The remaining portion of the liquid remains is returned to R101 and re circulated via the pump G001 through the reactor train , E003, D103 and finally R101. At steady state conditions , the vaporized quantity in D103 will be equal just to a fraction of the fresh plastic introduced in R101 because impurities and the high boiling fraction consisting of longer chain oligomers must be subtract ed. This fraction constitutes a product equivalent to fuel oil which increases over time in R101 as provided in the attached graph n° 5 and as described in con- nection with this document. From graph n° 5 (in the attached drawings, to be considered qualitative) the trend of the R101 level, which starts from a prede termined value chosen arbitrarily , to grow in time following the accumulation of higher boiling fractions which are not vaporized , is highlighted .The content of R101 will be partly or totally discharged into D104 when the spread between its level recorded immediately after the plastic has been charged and that after the vaporization cycle it becomes practically negligible to show that the liquid being processed is constituted by increasingly higher boiling compounds which are difficult to vaporize under the predetermined operating conditions. From R101 the fuel oil in D104 is transferred at discretized intervals where it is cooled by E005 and then sent to use once D104 has reached its maximum permitted level. The number of cycles required for unloading from R101 to D104 is a function of the operating conditions and of the type of plastic to be processed.