Method and device for producing hydrocarbon oils by pyrolysis based on plastic-containing feedstocks

Abstract

1. A method and reactor assembly for producing hydrocarbon oils by pyrolysis from a first plastic feedstock, comprising: optionally combining the plastic feedstock with a second feedstock selected from the group consisting of a hydrocarbon-containing feedstock selected from crumb rubber and wood chunks, the second feedstock constituting more than 15% by weight of the combined feedstocks; adding a catalyst to the combined feedstocks to form a reaction composition; feeding the reaction composition through an airlock valve (7) to an auger pyrolysis reactor comprising at least two auger reactors (1a, 1b) heated to a temperature in the range of 450-550°C; distributing oil vapors and non-condensable vapors from the auger reactors (1a, 1b) to a condenser; and condensing heavy and light oil fractions from the vapors in two stages.

Description

[Technical field]

[0001] The present invention relates to a method for the production by pyrolysis of hydrocarbon oils as indicated in the preamble of claim 1. According to another aspect, the invention relates to an apparatus as indicated in the preamble of claim 11. [Background technology]

[0002] The utilization of plastic raw materials for conversion into energy rich products in the form of fuel oil has become a major focus in the broader aspect of recycling and utilization of plastic raw materials.

[0003] Plastic raw materials can be incinerated as is, but toxic dioxins are generally produced during the incineration process.

[0004] Pyrolysis is a more promising candidate for environmentally friendly use of plastic waste to convert it into energy: in pyrolysis, the material is heated in the absence of oxygen and converted into a liquid oil product with a higher energy content that is more suitable for fuel than the raw plastic material.

[0005] There are a huge number of patent publications (patents and patent applications) in this technical field, such as U.S. Patent Nos. 5,608,136, 5,811,606, 6,866,830, 13,126,811, 5,856,599, 5,129,995, 8,344,195, 9,212,318, 9,725,655, and 10,093,860, and U.S. Patent Application Publication Nos. 2009 / 0062581, 2009 / 0321317, 2009 / 0221317, and 2009 / 0321318. Nos. 011 / 0259726, 2015 / 0001061, 2017 / 0073584, WO 2005 / 071043, 2007 / 069449, 2008 / 022790, 2010 / 049824, 2014 / 167141, 2018 / 000050, which relate to many different methods and types of pyrolysis equipment such as batch and rotary batch, fixed bed and fluidized bed, kiln and rotary kiln, and single, double and multi-auger reactors.

[0006] WO 2008 / 022790 and US 2009 / 0321317 relate to a method and apparatus for multi-auger pyrolysis of plastic-containing and organic fluids based on crude oil, edible oils, fats, etc. The reaction mixture is introduced into a reactor, melted in the melting zone of the reactor, and inhibitors are removed from the melt. The long chain polymers remaining in the melt are cracked in the cracking zone of the reactor until they reach a gaseous state. These patents disclose types of auger and multi-auger pyrolysis capable of treating the viscous material of such wastes as the plastic content melts, as well as shaftless (helical) screws. Plastic melt flooding occurs inside the reactor and becomes excessive relative to the non-melted parts, so there is no solution to limit such conditions while providing stable augering along the length of the reactor. As a result, auger and multi-auger pyrolysis systems have historically been unable to efficiently process plastic feedstocks due to melting and flooding.

[0007] In this regard, many patented solutions in the field of plastic pyrolysis, such as US Pat. Nos. 5,811,606, 6,866,830, 13,126,811, WO 2010 / 049824, WO 2018 / 000050, are based exclusively on melting and batch processes with stirring, such as batch pyrolysis reactors. A common problem with these methods is the deposition of coke at the bottom of the reactor, resulting in poor heat transfer and the need for frequent cleaning of the reactor, with unnecessary interruptions in production.

[0008] Conventional pyrolysis processes for plastic waste treatment have posed some problems because, although the required pyrolysis temperature is in the range of 450-500°C, plastics begin to melt at temperatures in the range of 150-200°C due to their characteristics.

[0009] In the pyrolysis of waste plastics, various catalysts are used for the purpose of lowering the temperature and upgrading the oil fuel to one with a low wax content, dolomite catalysts in U.S. Pat. No. 8,344,195, and ZSM-zeolite and FCC catalysts in U.S. Pat. No. 9,212,318. However, there is a typical problem of catalyst deterioration due to the incorporation of pyrolysis coke into the microporous surface area inside the catalyst, which requires the catalyst to be renewed or regenerated, or at least partially removed and mixed with new catalyst. The dolomite catalyst discussed in U.S. Pat. No. 8,344,195 is only proposed to be frequently removed and replaced with fresh catalyst prepared by oxidizing and calcining cheap fossil of natural dolomite material at temperatures of 900-1000 °C. It can therefore be recognized that there is no effective solution in the art for continuously regenerating the catalyst in parallel with the pyrolysis process.

[0010] Catalysts have been used in pyrolysis processes, but there are problems associated with their use. Auger-based reactors have problems with creating these molten conditions. Additionally, batch and continuous pyrolysis reactors experience the formation of a carbonaceous coke layer during the heating and pyrolysis of the liquid molten plastic. This condition deactivates the catalyst used in the pyrolysis process and reduces the rate of heat transfer. As a result, when reactors containing augers are used, a coke layer typically forms inside the reactor surfaces and on the auger shaft. Summary of the Invention [Problem to be solved by the invention]

[0011] It is therefore an object to provide a method and apparatus for improved pyrolysis of plastic raw materials in which the above mentioned disadvantages are reduced or eliminated. [Means for solving the problem]

[0012] The above mentioned object is achieved by a method defined by claim 1, which constitutes a first aspect of the present invention.

[0013] According to another aspect, the invention relates to a device as defined by claim 11.

[0014] Preferred embodiments are disclosed by the dependent claims.

[0015] In accordance with the present invention, a helical multi-auger reactor has been found to be useful in the pyrolysis processing of plastic-containing feedstocks. The plastic feedstock is combined with another feedstock having properties that serve to increase the viscosity of the reactant composition, preventing the reactant composition from forming a low-viscosity fluid mass under the reaction conditions in the reactor. At the same time, the combination of the reactant composition (blended feedstock) does not clog the reactor or form a carbonaceous coke layer on the reactor walls and auger parts. The deposition of such a coke layer is highly undesirable, as it reduces heat transfer and limits heat transfer between the reactor walls and the feedstock inside the reactor.

[0016] According to the method of the present invention, a first feedstock component in the form of a plastic is subjected to a process in combination with a second component, which may be either a specifically selected (first) catalyst or a second feedstock component selected from rubber and wood.

[0017] The safety standard for the reactor material SS304-321 corresponds to the temperature classification of around 800°C, which is sufficient for the use and regeneration of the AI2O3 catalyst at 650°C as required in the literature, and is the same for the typical catalyst ZSM-5, which is regenerated at 500-550°C.

[0018] In embodiments where the first catalyst is not present, the second feed component should not be less than 30% by weight if it is composed solely of rubber. If the second feed component is composed solely of wood particles, it should be present in an amount of 15% by weight or greater. This combination of feedstocks ensures that the viscosity of the mass is maintained at a constant level as it is conveyed through the reactor while providing a seal between the auger and the reactor walls, preventing the accumulation of char and other deposits on the reactor walls.

[0019] A similar effect can be achieved by incorporating into the plastic feedstock an effective amount of a catalyst that exhibits viscosity control properties. Such catalysts can be one or more metal oxides, such as alumina. Because plastic feedstocks can have a variety of physical properties depending on the type of plastic used, the amount of catalyst incorporated can be tailored to the particular feedstock.

[0020] Furthermore, the method and apparatus does not require interruption of operation since catalyst regeneration is inherent to the process. The catalyst regeneration temperature is about 650°C, which is about 150-200°C higher than the reaction zone temperature of the pyrolysis process. The most suitable catalysts for this process are zeolite catalysts, AI2O3 and / or dolomite based catalysts.

[0021] A further unique feature of the present invention is that heating is provided at least in part by combustion of gases generated in the process, in this sense the apparatus and method of the present invention does not require external heating or can be combined with electric or other heating only where external heating is commercially advantageous.

[0022] At the reaction temperatures, the oil produced vaporizes and must be cooled to liquid oil. The vapors are preferably cooled in two stages to produce different oil fractions: a heavy oil fraction and a light oil fraction.

[0023] The invention will now be described in more detail in the following by way of non-limiting embodiments with reference to the drawings. [Brief description of the drawings]

[0024] [Figure 1] 1 is a schematic simplified flow scheme showing the basic elements of the apparatus and method of the present invention. [Diagram 2] 1 is a schematic layout diagram of an overall plant incorporating the basic elements of the present invention; [Diagram 3]FIG. 2 is a cross-sectional side view of some core elements of a device according to the present invention. [Figure 4] FIG. 4 is an exploded cross-sectional side view of the same components as in FIG. 3; [Diagram 5] FIG. 4 is a side cross-sectional view of another element of the device according to the invention. [Figure 6A] FIG. 2 is a detailed view of the condenser element of the device according to the invention. [Figure 6B] FIG. 4 is another detailed view of the condenser element of the device according to the invention. [Figure 7] 7A-7C are diagrams illustrating the operation of the condenser element shown in FIG. 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] FIG. 1 shows a heat box 2 or retort that encloses a first auger reactor (1a) and a second auger reactor (1b) connected in series and a third tubular reactor (1c) connected in series to the second auger reactor (1b). An airlock valve 7 is shown at the inlet of the first auger reactor and another airlock valve 8 at the outlet of the second auger reactor 1b. In the lower region of the heat box 2, a heating device 3, usually in the form of a gas flame furnace including a burner 4, is arranged for heating the various reactors to the desired temperatures. Insulation may be present in the heat box and / or the heat box may have inherent insulating properties. The heating device 3 may preferably include a burner 4 that utilizes non-condensable gases generated in the process as fuel.

[0026] A material stream (III) in the form of hot oil vapor is shown, from the location of the outlet of the first and second auger reactors 1a, leading the hot oil vapor to a first cooling unit in the form of an oil condenser 11, where the heavy fraction of the hot vapor (heavy oil boiling range) is converted into a heavy oil fraction. This is carried out at a temperature of about 100°C. The remaining vapor is sent to a second condenser 12, where the temperature is further reduced and the condensable vapor is converted into a light oil fraction V. The first condenser 11 is cooled, preferably using hot water, or boiling water. The second condenser 12 is usually cooled with hot water, at a temperature in the range of 60-75°C.

[0027] The flows shown in FIG. 1 are: I: Feedstock containing most of the plastic feedstock, II: Catalyst recycle flow, III: Oil vapor from the auger reactor, IV: Non-condensable gas (containing hydrogen) used for heating, V: Pyrolysis oil as the main product of the present invention, VI: Fresh water, VII: Boiling water for cooling / condensing the hot vapor, VIII: Steam generated during cooling of the hot oil vapor, which is usually further used in char treatment / catalyst regeneration, IX: Cooling water for cooling and condensing the lighter vapor fraction, X: Ash residue and waste water, XI: Exhaust flue gas.

[0028] Preferably, the first and second auger reactors are shaftless, meaning that the auger at the outlet end may rotate at a different speed than the auger near the inlet end of the reactor(s), which serves to optimize residence time and ensure a more consistent filling of the auger reactor from inlet to outlet, depending on the volume fluctuations caused by the pyrolysis process proceeding throughout the length of the auger.

[0029] In operation, the feedstock and catalyst are loaded through airlock valve 7 into the first auger reactor 1a which is heated to a temperature in the range of 450-500°C. To initiate the pyrolysis process, start-up fuel oil is used as a start-up fuel to achieve the pyrolysis temperature. The process then uses self-generated pyrolysis off-gases for continuous heating of the process to achieve the process temperatures mentioned above. The auger is operated to convey the feedstock through the first reactor at a rate selected to achieve a suitable residence time for the desired pyrolysis to take place.

[0030] When a second feedstock is combined with the plastic feedstock, the catalyst is typically selected from the group consisting of dolomite, zeolite, natural or industrially granulated catalytic materials that are heterogeneous catalytic materials that can operate at lower pyrolysis temperatures and still refine and maximize the pyrolysis oil products.

[0031] When plastic raw materials are used as the sole raw material, the catalyst of choice is typically AI2O3, although CaCO3, MgCO3, fly ash, etc. can also be used alone or in combination.

[0032] When a second feedstock is combined with the first feedstock, the catalyst is preferably selected from among zeolitic catalysts.

[0033] In catalytic pyrolysis, catalyst deactivation is prone to occur due to impurities of carbonaceous coke deposited on the micro-porous surface area of ​​the catalyst. Usually, the catalyst needs to be replaced or thermally regenerated. As known from studies and publications in [5-7], the regeneration of the catalyst, especially of zeolitic catalysts such as ZSM-5, HZSM-5, HUSY, can be carried out by burning off the impurity of coke. The regeneration of the catalyst is carried out by slow oxidation with air at temperatures below 550 °C to avoid irreversible decrease of the acidity of the catalyst and the so-called catalyst calcination temperature. Calcination can be avoided by periodic stirring and supply of cooling steam agent.

[0034] The tubular reactors 1a, 1b, 1c are arranged to maximize thermal efficiency based on hot gas flowing upwards in various temperature zones, flowing through the heat box in cross-flow indirect transfer of hot gas as shown in Figure 1.

[0035] In the first auger, the plastic feedstock heats up and begins to melt in the range of 180-250°C, while the crumby rubber used as the second component of the feedstock typically decomposes at temperatures above 350°C. This means that the rubber feedstock acts as a filler, aiding in stable screw rotation and helping to maintain a constant viscosity of the feed as a whole.

[0036] The viscous fluid mixture together with the catalyst flows into the second auger reactor 1b at a reduced rotational speed to ensure a steady near-full cross-sectional flow of the reactor over the treatment length. In the second auger reactor, the pyrolysis material mass is broken down and vaporized while the residence time in the reactor is significantly extended. The unconverted pyrolysis carbon is removed through a rotary lock valve into a third tubular reactor with the characteristics described below.

[0037] The third tubular reactor 1c is a kind of regenerative tubular reactor, typically housing a shaft-based pedal agitator, in which the remaining feedstock is heated to a higher temperature than in the auger reactor, with the aim of continuously regenerating the catalyst by agitation and thermal oxidation with the supply of air and steam. The third tubular reactor is arranged in a paddle shaft design and is hermetically separated from the other parts. This allows both the pyrolysis catalyst and the self-regenerating catalyst to be maintained at a common heating temperature, typically in the range of 500-550 °C. To avoid catalyst burning, a cooling steam agent is typically added. Carbon monoxide and hydrogen are generated in this process.

[0038] Figure 2 is a schematic of a reactor arrangement based on the principle shown in Figure 1, including further elements that are usually present in a practical embodiment, such as NOx and SO2 scrubbers, and a water filter. The main concept of the process is similar to Figure 1. The flows indicated by the Roman numerals are as described above with reference to Figure 1.

[0039] 3 is a cross-sectional side view of heat box 2 which houses two auger reactors where pyrolysis takes place and a third tubular reactor where the catalyst is regenerated. As can be seen in the two auger reactors, the augers are split into inlet and outlet halves, allowing the rotation speed of the outlet side to be different from the rotation speed of the inlet side.

[0040] A typical arrangement of crushing, granulating and feeding units, usually applied for waste plastics, is preliminarily prepared for the co-pyrolysis processing of blended mixtures as part of the invention to the present system. It also includes a rotary airlock valve, which is preferably proposed for chopping and feeding of blended mixture bulk feedstock consisting of rubber mixtures up to 5-6 mm size. At the same time, in case of woody biomass / chips, typically a double flap airlock valve is used for the filling of woody biomass / chips of 20 mm-25 mm. This is mainly due to the characteristics of wood hardness and chip size, which are prone to clogging in the rotary airlock valve.

[0041] As a detailed embodiment of the system, it is proposed that the shell-tube body of the double auger shaftless pyrolysis reactor is typically made of boiler steel 1020 or 1040 (thickness 6-10 mm depending on diameter) and since the process is carried out in the absence of oxygen, the internal shaftless helical screw can also be made of the same steel and thickness.

[0042] In contrast, the shell tube body of the catalytic retort, including the internal multi-paddle screw, must be specially manufactured from stainless steel SS304 or SS321, because the thermal oxidation conditions caused by the air supply for catalyst regeneration inside are around 550°C to 550°C, and in some cases up to 650°C.

[0043] Geared cycloidal and flange-retained AC motors are typically used to rotate the augers of the screw pyrolysis reactors and catalytic retorts. Both are specially equipped with frequency inverters (HZ drivers) to achieve different rotational speeds. The rotational speeds range from a minimum of 1.0 rpm to a maximum of 7.5 rpm. The corresponding operating power capacities range from 1.5 kW to 5.5 kW (depending on the auger diameter). Auger speed can be both manually controlled and PLC controlled for an automated process with feedstock specific product control. The start-up of the reactor is performed by an industrial dual fuel burner 4, an automatic burner to preheat the pyrolysis reactor to the pyrolysis temperature of 450 °C. This is done within 1.5 hours.

[0044] The automatic adjustment of the flame control of the fuel burner 4 is adjusted so that the flame temperature in the furnace 3 is in the preheat range of 550-850°C provided by its automatic medium-max operating mode to achieve the operating temperature of the reactor. Correspondingly, the steam over-pressure in the steam boiler 21 is adjusted to be about 0.5 bar or higher, at the same time that the boiler is typically and automatically fed with water.

[0045] When the motor-controlled valve 20 for supplying steam into the catalytic retort 2 is automatically or manually closed, the steam is discharged to the outside, typically as shown in Figures 1 to 3. As a result of this preheating, the boiler 21 is already in operation, so that the oil condenser 11 is already sufficiently filled with boiling water. The blower fan is first turned on, and the under-pressure in the furnace is typically -0.05 kPa or higher. Under these thermal and other conditions, the system is ready for loading and operation, as discussed below.

[0046] Steam added via motor controlled valve 20 serves to control the temperature within tubular reactor 1c where catalyst regeneration takes place.

[0047] The system is equipped with an automatic control system, but can also be operated manually. Figures 5-6 show a typical PLC control configuration for gas flame temperature control where the combustion air A1 in the furnace 3 is supplied by a blower 6. The outlet temperature control of the catalytic retort is provided by steam coolant supplied by a motor controlled valve 20, and the oil condensation temperature outlet control of both oil condensers 11-12 is provided by boiling water and cooling water screw pumps 16. Also, the system can be simplified and implemented by manual control procedures as preferred in lab scale or pilot plant. At the same time, the control level performance of the steam boiler 21 and both oil line pumps are automatically provided as required by standard regulations for such units.

[0048] In relation to the above, the present system for industrial oil burners and their start-up preheating is also typically in an automatic control mode. In particular, the three-stage operation mode such as low heat, medium heat, and high heat as considered in the present system will be described later.

[0049] The heat capacity of the burner is typically not less than that of the residual gas combustion rate of 15-20% by weight of the mixed plastic heat content after pyrolysis oil condensation, and 80-85% of the corresponding heat capacity is achieved. The burner is operated and controlled in three-stage modes such as low flame, medium flame, and high flame, as will be considered in detail for the description of the present system. Regarding the heat capacity, the following ratios approximately correspond: This system has a capacity of 0.35MW for preheating 0.25 tons / hour. This system has a capacity of 0.5 MW for preheating 0.5 ton / hour. This system requires 0.75MW for preheating 1.0 ton / hour

[0050] As shown in a fragmentary manner in FIG. 3, in this system, all augers and heat boxes 2 of the pyrolysis reactors 1a, 1b, 1c, as well as rotary or double flap airlock valves 8-9 and discharge auger 10, together with the preheating of the reactors, are configured to be switched into operation mode. The sequence of steps starting from the last feeding unit that supplies the rotary airlock valve 8 to the first feeding unit must be switched on to operate in the last step before operating any of the typical conveyor or hopper type feeding systems. Finally, the sequence when the latter is started to load the reactor, the sequence when the gas fan 5 is switched on at the same time, the sequence where the pyrolysis oil vapors discharged from the process are sent from the reactors to the oil condenser 11-12 via piping, and the piping sequence from the condenser back to the gas furnace 3 to recycle the non-condensable residual gas are typically configured as a simultaneous sequence technique. This also solves the requirement of low pressure conditions in the pyrolysis reactors, around -50 Pa, which is usually required with a single fan configuration.

[0051] As shown in Figure 5, it is estimated that after approximately 0.5 hours of loading into the system, the combustible residual syngas is available for injection through the multi-orifice nozzle and piping into the furnace 3 as described above. The regenerated gas is ignited by a preheat oil flame burner 4 operating at a preheat temperature of 800°C to 850°C. As a result of the regenerated syngas being injected into the furnace, the temperature rises to around 1000°C in 5 to 10 minutes. To regulate the flame temperature of the burner, it is automatically set to its minimum operation with a low flame setting. This is achieved by a three-stage mode. Meanwhile, the blower 6 is automatically activated and starts the operation of diluting the gas with the combustion air A1 necessary to stabilize the gas flame temperature not exceeding 1000°C. In case of an emergency where manual control is desired, the blower can be manually controlled to perform the same operation at the same time. A temperature rise to around 1100°C is permitted.

[0052] The operating temperature of the pyrolysis furnace is around 500°C and the heat required for the pyrolysis process is provided by indirect sweeping of hot exhaust gases at 700-750°C around the furnace, so that the latter is achieved by the sweep temperature, as proposed to be regulated by another dilution air injection point A2. This can be easily done manually through an opening with a flip-flap damper arrangement 19 as shown in Figures 1 and 3.

[0053] At these thermal conditions, both the furnace 3 and the reactor 1 are proposed for stable continuous operation for catalytic pyrolysis of mixed plastics with new and innovative configuration performances described below. Figure 4 shows the change in bulk volume of mixed plastics due to heating, melting and pyrolysis, and the stable screw rotation in the pyrolysis reactor. The bulk plastics subjected to melting in the reactor are reduced in bulk volume by 2-2.5 times due to crumb rubber and wood chips. In the case of plastic flake processing, a reduction of 6-7.5 times (per kg of mixture) is estimated, suggesting that all the plastic melt is contained in the porous volume of these bulk material media (excluding the catalyst).

[0054] Bulk density of plastic flakes = 100kg / m 3 Bulk density of plastic granules = 500kg / m 3 Bulk density of crumb rubber = 350 kg / m 3 Crumb rubber bulk porosity = 68% Bulk density of wood chips = 150 kg / m 3 Porosity of wood chips = 80%

[0055] Version 1: Mixture of plastic granules and crumb rubber (65 / 35% by weight): Mixture volume fed = 0.65 / 500 + 0.35 / 350 = 2.3 liters Volume of mixture melted = bulk medium of crumb rubber = 0.35 / 350 = 1 liter

[0056] Version 2: Mixture of plastic granules and wood chips (80 / 20% by weight): Mixture volume fed = 0.8 / 500 + 0.2 / 150 = 2.95 liters Volume of mixture melted = bulk medium of wood chips = 0.2 / 150 = 1.35 liters

[0057] Version 3: Mixture of plastic flakes and crumb rubber (65 / 35% by weight): Mixture volume fed = 0.65 / 100 + 0.35 / 350 = 7.5 liters Volume of mixture melted = bulk medium of crumb rubber = 0.35 / 350 = 1 liter

[0058] Version 4: Mixture of plastic flakes and wood chips (80 / 20% by weight): Mixture volume fed = 0.8 / 100 + 0.2 / 150 = 9.35 liters Volume of mixture melted = bulk medium of wood chips = 0.2 / 150 = 1.35 liters

[0059] In this regard, Figure 4 shows the proposed variable rotation speed as a configuration for operation with the mixture as described in the sample calculation. In the case of the proposed crumb rubber mixed with plastic granules, the molten state usually occurs preferably in the upper part of the double auger pyrolysis reactor, especially in the second half screw section of the double auger pyrolysis reactor of the present system, as shown in Figure 4. The setting of the rotation speed of the auger is important, and for this reason, the latter auger is rationally operated at a rotation speed 2 to 2.5 times lower than the first auger to roughly stabilize the flow in the reactor cross section and provide more effective pyrolysis processing conditions of longer residence time.

[0060] By analogy, the mass and bulk of the mixed feed is also significantly reduced due to its devolatilization (evaporation). For this reason, it is proposed that the third and fourth half screw sections of the reactor are operated more effectively at a reduced rotation speed, as specifically and advantageously shown in Figure 4. As a result, the total residence time in the twin auger reactor of the present invention is improved by around 45% (with an accuracy of 0.5 minutes), as exemplarily and proportionally estimated as follows for plastic granules containing crumb rubber:

[0061] In the case of a typical dual auger reactor (both upper and lower augers are hole screw design) for plastic-rubber co-pyrolysis Residence time in top auger (e.g. 5 rpm) = 15 minutes Residence time in lower auger (2.5 rpm) = 30 minutes Total residence time for processing = 45 minutes

[0062] In this system, an innovative double auger reactor (both upper and lower augers are half screw design) Residence time in the first half screw section of the upper auger (e.g., 5.0 rpm) = 7.5 minutes Residence time in the second half screw section of the upper auger (2.5 rpm) = 15 minutes Residence time in the third half screw section of the lower auger (2.0 rpm) = 18.5 min Residence time at the 4th half screw section of the lower auger (1.5 rpm) = 24.5 min Total residence time for processing = 65.5 min

[0063] A claim for multi-rate pyrolysis of a solid mixture of mixed feedstocks and the catalysts used in its processing, carbon char loaded from crumb rubber or wood chips and possibly a small loading from plastics, all fed from reactors 1a, 1b to a catalyst regeneration retort 1c, fed to the pyrolysis retort by rotary airlock valve 7 as an inlet feeder and also fed to the pyrolysis retort by rotary airlock valve 8 as an outlet feeder.

[0064] These airlock valves are necessary to separate the air and steam supply to the retort under low oxidizing atmospheric pressure, both with respect to the outside air and the air inside the pyrolysis reactor. For thermal regeneration of such catalysts, low oxidizing conditions are typical, where the catalyst coke impurities are slowly burned and gasified at temperatures around 500-550°C. This is done by oxidizing air A2 supplied through a regulating damper valve 20, and by operating in a counter-flow direction to the moving catalyst bed in the retort, as shown in Figure 3, effective thermal treatment and regeneration is possible.

[0065] For the purpose of zero waste processing, an alternative option has also been proposed: burning carbon char at the same temperature in the retort with thermal regeneration of the catalyst, the latter usually stabilized by balancing the heat release of the carbon char with excess oxidation air A3 regulated as described above, and additionally cooling steam provided from a steam boiler 21 by the motor-controlled valve 20 described above. This process is carried out with a self-regenerating catalyst under purification of the char.

[0066] The char refining process is carried out by stirring, as shown in Figure 3, where a paddle auger type catalytic retort 2 is proposed, which specifically and preferably operates at a rotation speed of 5 rpm, as shown in Figure 3. If the low oxidation temperature is not balanced with the cooling procedure proposed in the above procedure, localized spontaneous combustion of the carbon char may occur.

[0067] As explained above, stirring at a maximum rotation speed is provided, exemplarily and preferably proposed as 5 rpm. The capacity of the paddle screw is proposed to correspond minimally to the capacity of the fourth half screw part of the lower auger. The proposed paddle screw rotation speed is 1.5 rpm, which corresponds to 14.5 minutes. The proposed residence time in the heat box is more than twice that of the half screw in the case of the whole screw design, specifically more than 29 minutes. Similar to the above paddle screw configuration, a residence time for cooling and unloading / discharge of the catalyst conveying screw 10 is also proposed to be around 30 minutes, with a corresponding discharge temperature of the cooled catalyst of 50°C. With this approach, the CW-auger screw 10 is operated correspondingly at the same low rotation speed, exemplarily 1.5 rpm, as shown in Figures 1 to 3.

[0068] The present invention also relates to a method for producing NOx that may be generated in a gas furnace 3 that is specially operated in a high temperature range of 1000°C. X It provides a reduction of pollutants with the aim of minimizing emissions. Therefore, in order to prevent the formation of dioxins at their low values, it has been proposed to recirculate the combustion flue gas from the retort 2 to the same furnace, as shown in Figures 1 to 3. This, by analogy, reduces the NOx emissions in the high-temperature combustion zone, as shown for example in Figure 5. X This is done by the so-called MILD combustion method, with the EGR coefficient (exhaust gas recirculation) known and recommended for reduction. As mentioned before, it can also be done by itself, due to the furnace under-pressure around -50 Pa.

[0069] The pyrolysis oil production using vertical and horizontal shell-and-tube series oil condensers 11 and 12 for selectively condensing heavy oil fraction in the first condenser is innovative due to the normal temperature cooling water supply that is usually applied in the conventional pyrolysis process. The present invention claims that the pyrolysis steam is cooled from the inlet temperature of 400°C to the outlet temperature of 200°C of the condenser 11 by the boiling water supply at 100°C from the steam boiler 21 as shown in Figure 6(a), and preferably 65% ​​of the pyrolysis oil is condensed.

[0070] Being close to the boiling temperature of water, some of the fractions will evaporate and these non-condensable gases will be recirculated through the steam pipes into the boiler drum. The condensation temperature of this new condenser is controlled by PLC control or manual procedure by the feed water volume, which usually depends on the oil vapor outlet temperature. This difference can also be concluded that the water temperature is stable at 100°C even if the feed water volume fluctuates. However, the water level in the condenser is the only variable between the tube bundles as shown in Figure 7, so the condensing surface of the tubes is also considered as a necessary variable for the new control mode sequence.

[0071] In contrast to the vertical condenser 11, the water level in the horizontal condenser 12 is stable as shown in Figure 6(a). This is because the proposed temperature of about 65-70°C provides a stable temperature for condensing the light oil fraction, whereas the flash point of oil is around 55-60°C. This claim is a new and innovative one, with both upper and lower tube bundles in the condenser bulk water, as shown in Figure 6(b). In this configuration, the oil vapor stream is cooled and condensed in the lower tube bundle, while the upper tube bundle is supplied with ambient cooling water, which quenches the bulk water in the condenser 12 to a temperature of 65-70°C as mentioned above. In such a condenser, there is an advantage that there is a closed loop natural (gravity) water circulation, where the relatively cool bulk water is supplied from the upper region. This is cooling by ambient water, which is supplied to the upper tube bundle and circulates downwards to the lower region. In the lower tube bundle region where the condensed oil is heated, as shown by the arrows in Figure 6(b), the water circulates upwards again together with the oil, and does so in the same temperature range as before.

[0072] Regarding the other embodiments and configurations of these condensers, both are equipped with an open column type oil-based hydraulic airlock vessel 13 for piping the oil from the condenser, where it is possible to see the oil flowing down from the condenser, as shown in Figures 6-7. The oil piping from the heavy oil condenser 11 is all made with a rectangular design, and all piping configurations are equipped with pack seal piston bars. This is to allow the piping to be cleaned in case of tar or wax solidifying and clogging. This avoids emergency shutdowns and long cooling times of the system. As with the oil vapor piping arrangements to these condensers, they are equipped with multi-lens industrial type thermal expansion joints 14 with hot pipes as usual. The screw type water pump 16 is preferably configured with a PLC control procedure for both boiling water and cooling water supply, as previously mentioned. There is flexibility to adjust variable water supply mode and continuous water supply mode simultaneously. [Explanation of symbols]

[0073] 1a First Auger Reactor 1b Second Auger Reactor 1c Third tubular reactor / catalyst regeneration 2 Heat Box / Retort 3 Gas-fired furnace 4. Industrial oil burner for preheating 5 Gas fan for furnace piping 6 Pre-start combustion blower 7 Airlock Valve 8 Airlock Valve 9 Airlock Valve 10 Discharge auger / CW auger screw 11 Vertical oil condenser / heavy oil condenser 12 Horizontal condenser for light oil fraction 13 Airlock Container 14 Thermal Expansion Joints 15 Gear type pyrolysis oil pump 16 Cooling water screw pump 17 Pack Seal Piston Bar 18 Control valve 19 Flip-Flap Damper Arrangement (Valve) 20 Air regulating damper valve 21 Steam boiler 22 Exhaust valve

Claims

1. A method for producing a hydrocarbon oil from a first plastic raw material by thermal decomposition, comprising: Optionally, combining the plastic feedstock with a second feedstock selected from the group consisting of a hydrocarbon-containing feedstock selected from crumb rubber and wood chunks, the second feedstock comprising greater than 15% by weight of the combined feedstocks; adding a catalyst to the combined ingredients to form a reaction composition; feeding said reaction composition through an airlock valve (7) into an auger pyrolysis reactor comprising at least two auger reactors (1 a, 1 b) heated to a temperature in the range of 450-550°C; Distributing oil vapor and non-condensable vapor from the auger reactor (1a, 1b) to a condenser; condensing a heavy oil fraction and a light oil fraction from said oil vapor and said non-condensable vapor, preferably in two stages (11, 12); A method characterized by:

2. If the second feedstock is not combined with the first feedstock, the catalyst is ２ O ３ , CaCO ３ , MgCO ３ , fly ash, used alone or in combination.

3. 10. The method of claim 1, wherein when the second feedstock is combined with the first feedstock, the catalyst is selected from among zeolite-based catalysts.

4. 10. The method of claim 1, further comprising the additional step of treating the char resulting as residue from the auger reaction step at a temperature in the range of 500-550°C, thereby producing carbon monoxide and hydrogen.

5. 5. The method of claim 4, wherein the additional step of treating the char is carried out in a tubular reactor equipped with paddle stirring means.

6. 5. The method of claim 4, further comprising the step of regenerating a coke-forming catalyst during said additional step carried out at 500-550°C.

7. 10. The method of claim 1, comprising at least partially heating the reactor with heat generated by a burner fed with non-condensable gases produced in the auger reactor.

8. 10. The method of claim 1, wherein the heavy oil fraction is condensed using boiling water at a temperature of about 100°C.

9. 2. The process of claim 1, wherein the light oil fraction is condensed using hot water at a temperature in the range of 60 to 75°C.

10. 10. The method of claim 1, wherein said second hydrocarbon feedstock, when comprised solely of crumb rubber, is present in an amount of 30 wt.% or greater.

11. 1. A reactor assembly for producing a hydrocarbon oil by pyrolysis from a first feedstock comprising a plastic feedstock, comprising: a. a supply of plastic raw materials and at least one additional hydrocarbon-containing raw material selected from rubber and wood; b. A helical reactor equipped with at least a main shaftless double auger (1a, 1b), a variable speed motor that allows the rotation speed at the outlet to be different from the rotation speed at the inlet; c. Airlock valves (7, 8) at both the inlet and outlet of the reactor; d) a third tubular reactor (1c) located downstream of the primary at least double auger reactor (1a, 1b); e. A heat box (2) arranged to surround at least the double auger reactors (1a, 1b) and the tubular reactor (1c); f. an oil condenser arranged in at least two stages; g. a burner (4) for heating the reactor assembly, the burner (4) being configured to be supplied with a non-condensable combustible gas; h. A boiler (21) for producing hot water and steam arranged to condense the pyrolysis gases, preferably the light oil fraction and the heavy oil fraction in oil condensers (11, 12); A reactor assembly comprising:

12. 12. The reactor assembly according to claim 11, wherein the oil condensers (11, 12) are of the shell-and-tube type.

13. 12. The reactor assembly of claim 11, wherein the third tubular reactor (1c) comprises a shafted paddle configured to regenerate the catalyst using thermal oxidation.

14. 14. Reactor assembly according to claim 13, wherein said third tubular reactor (1c) is gas-tightly separated from said main at least double-auger reactor (1a, 1b).

15. 14. The reactor assembly according to claim 13, wherein a supply (20) of oxidation air and cooling steam is arranged at the inlet of the third tubular reactor (1c).

16. 16. Reactor assembly according to claim 14 or claim 15, showing means for conveying exhaust gases from the outlet of said third tubular reactor (1c) to said burner (4).

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