Process and system for converting plastic material into liquified petroleum products

Abstract

The present invention provides a process for converting plastic material into liquified petroleum products. The process includes feeding the material into at least one thermolysis reactor of a plurality of reactors, for thermolysis of the material by indirectly heating the said plastic material at a temperature in a range of 400 °C to 450 °C for thermally cracking the plastic material to obtain the gaseous petroleum products. The process further includes directing the gaseous products into one or more condensers. The process further includes condensing the gaseous products in the condensers to convert the gaseous products into the liquified petroleum products. The at least one thermolysis reactor being operated by heat generated by utilizing non-condensable gaseous remains obtained during the condensation of the said gaseous petroleum products, thereby leading to the indirect heating of the said plastic material.

Description

PROCESS AND SYSTEM FOR CONVERTING PLASTIC MATERIAL INTO LIQUIFIED PETROLEUM PRODUCTSFIELD OF THE INVENTION

[0001] The present invention relates to the field of processing waste plastic material into petroleum products. More particularly, the present invention discloses a process for converting plastic material (waste plastics) into liquified petroleum products.

[0002] Plastic has been widely used in many industries due to its lightweight, corrosion resistance, easy processing and molding, low cost, and convenient use.

[0003] Plastic products have penetrated every comer of society from industrial and agricultural production to clothing, food, housing, and transportation.

[0004] There are billions of tons of plastic products in the world. With the vigorous development of the plastics industry and its large-scale use, waste plastics have brought serious social problems: because waste plastics are discarded in large quantities, are not easily degraded, are difficult to handle, and have a wide range of impacts, resulting in a great waste of energy and in environmental pollution.

[0005] Recycling waste plastics as renewable energy is a promising idea. The technology of pyrolyzing / thermolyzing waste plastics to prepare fuel is a good way to recycle plastic waste from solid waste.

[0006] However, the existing industrial application of waste plastic cracking to prepare oil products mainly uses a pyrolysis kettle (or cracking kettle, reaction kettle, etc.) to directly heat waste plastics.

[0007] Direct heating of waste plastics consumes more energy, leading to an increased overall cost of the treatment.

[0008] Furthermore, due to the poor thermal conductivity of the waste plastics, slow heat transfer is achieved in the reactor, which results in incomplete crackingand produces high coke materials thus the total solids discharged and reducing the petroleum products content in the petroleum product.

[0009] However, if one simply increases the heating temperature, there will be local overheating, easy coking, etc., which leads to low-quality petroleum products converting molten plastics into vax.

[0010] Further, thermal cracking of the waste plastic at very high temperatures may lead to higher energy consumption, increasing the treatment's overall cost.

[0011] Furthermore, in the existing methods / processes, to make the property of synthesized oil products effective, it is a common practice to use one or more catalysts for thermal treatment of the waste plastic for converting the waste plastic to fuel products.

[0012] One such type of invention which utilizes a catalyst is disclosed in United States patent no. 9200207.

[0013] The said patent 207’ discloses a method of producing liquid hydrocarbon fuels from solid plastic wastes. The method includes mixing solid plastic waste with a metal hydride and a supported metal catalyst. The method further includes gasifying the mixture and producing high-quality liquid fuels.

[0014] Another such type of invention is disclosed in Chinese Utility document no. 206666457.

[0015] The said document 457’ discloses a system that a kind of plastics pyrolytic gasification prepares oil products. The system includes a pyrolysis oven that is adapted to pyrolyze the waste plastic using the catalyst / s. The system further includes a heat storage type gas radiation pipe burner that is arranged on an annular furnace wall of the pyrolysis oven.

[0016] However, the processes for pyrolysis treating the waste plastic using the catalyst / s provides a problem of an expensive running cost and a health hazard incurred by poisoning with mixed foreign matters.

[0017] Further, the petroleum products produced by utilizing the catalyst / s are susceptible to changes in their chemical property in a long run which leads to degradation of the quality of the petroleum products.

[0018] Therefore, there is an urgent need in this field to develop a process and system for treating waste plastics that is clean and environmentally friendly, has low energy consumption and cost, high oil yield, and stable oil quality, especially to solve the worldwide technical problem of easy coking in the cracking reactor.

[0019] Further, there is a need for a continuous process and system for converting waste plastics into high-quality liquified petroleum products without the need for catalyst / s.

[0020] Furthermore, there is a need for a process and system for converting waste plastic into vax-free liquified petroleum products even at low temperatures.

[0021] In addition, there is a need for a process and system for converting waste plastic material into liquified petroleum products which may utilize heating in such a way that the reactors may operate at an optimum temperature range for converting the waste plastic into the liquified petroleum products more efficiently.

[0022] Moreover, there is a need for a process and system for converting waste plastic material into liquified petroleum products which may reduce the consumption of externally supplied fuel to operate the process.

[0023] In a nutshell, a process and system are required which may overcome the drawbacks discussed above and provide an efficient and cost-effective way for converting plastic material into liquified petroleum products.SUMMARY OF THE INVENTION

[0024] In an aspect of the present invention, a process for converting plastic material into liquified petroleum products is disclosed.

[0025] The “plastic material” herein refers to a material consisting of a wide range of synthetic or semi-synthetic organic compounds.

[0026] In an exemplary embodiment of the present invention, the said plastic material may include waste plastic material such as industrial waste plastic.

[0027] In one embodiment of the present invention, the process involves feeding the said plastic material from a material storage into a melting reactor via a feeding system.

[0028] In one embodiment of the present invention, the process includes pretreatment of the said plastic material before the feeding of the plastic material into the material reactor.

[0029] In one embodiment of the present invention, the process involves melting the said plastic material in a melting reactor of the plurality of the reactors.

[0030] In the embodiment of the present invention, the melting is carried out by operating the melting reactor at a temperature in a range of 350 °C to 400 °C continuously to obtain molten plastic material and maintain a bed of molten plastic.

[0031] Further, the process involves discharging the said molten plastic material into at least one thermolysis reactor of the plurality of reactors.

[0032] In an exemplary embodiment of the present invention, the melting reactor is being fed with plastic material gradually and continuously for allowing melting of the plastic material up to a bed level to the required height after completing the discharging of molten plastic to at least one thermolysis reactor.

[0033] In one embodiment of the present invention, the process involves thermolysis of the plastic material in the at least one thermolysis reactor by indirectly heating and maintaining the said plastic material at a temperature in a range of 400 °C to 450 °C for about up to 7 hours for thermally cracking the plastic material to obtain the gaseous petroleum products.

[0034] “Thermolysis” refers to the chemical decomposition of a substance or thermal cracking of hydrocarbons in the petroleum industry.

[0035] The “gaseous petroleum products” herein refer to hydrocarbon gaseous compounds that form as a result of the cracking of the polymers in the molten state during thermolysis.

[0036] In one embodiment of the present invention, the thermolysis is carried out in a first thermolysis reactor of the said at least one thermolysis reactor for about up to 7 hours.

[0037] In another embodiment of the present invention, the thermolysis is carried out in a second thermolysis reactor of the said at least one thermolysis reactor for about up to 7 hours.

[0038] Further, the process involves directing the said gaseous petroleum products to separate condensers connected to each thermolysis reactor.

[0039] In one embodiment of the present invention, the process involves condensing the gaseous petroleum products in the condensers to convert the said gaseous petroleum products into liquified petroleum products.

[0040] In an exemplary embodiment of the present invention, about 82% - 85% of the gaseous compounds get condensed at room temperature to form liquified petroleum products such as diesel or petrol.

[0041] In the embodiment of the present invention, about 10% - 12% of the gaseous compounds may not get condensed at room temperature.

[0042] In the embodiment of the present invention, these non-condensable gases consist of methane and are pumped into a heat generation system which generates the heat required for operating the plurality of the reactors and other components required to carry out the process.

[0043] More specifically, these non-condensable gases are transported to a molten salt boiler of the heat generation system via a pumping system.

[0044] In the embodiment of the present invention, these non-condensable gases get combusted continuously in the molten salt boiler with supplied combustion-airfor generating heat for operating the plurality of reactors via a heated molten salt stream.

[0045] In another embodiment of the present invention, the heating may also be provided by other indirect heating technologies.

[0046] In one embodiment of the present invention, the thermolysis of the molten plastic material may also result in fillers that remain in the thermolysis reactors in a dense slurry form (densified molten plastic form).

[0047] In the embodiment of the present invention, the densified molten plastic with filler material is discharged from the said at least one thermolysis reactor into a recovery reactor by opening a third valve.

[0048] Subsequently, the process involves condensing (already mentioned in the above paragraphs) the said gaseous petroleum products to produce the liquified petroleum products.

[0049] In another aspect of the present invention, a system for carrying the above- mentioned process for converting plastic material into liquified petroleum products is disclosed.

[0050] The system includes one or more cleaning devices for cleaning the said plastic material.

[0051] In one embodiment of the present invention, the system further includes a shredding device for shredding the said cleaned plastic material.

[0052] In one embodiment of the present invention, the system includes a palletizing device for palletizing the said shredded plastic material to form pallets of the said plastic material of uniform sizes.

[0053] In one embodiment of the present invention, the system includes the plurality of reactors that includes the melting reactor for melting the said plastic material.

[0054] In one embodiment of the present invention, the system further includes the feeding system to feed the said plastic material from a material storage into the melting reactor.

[0055] In one embodiment of the present invention, the said plurality of reactors includes at least one thermolysis reactor for treating the said plastic material for converting the plastic material into gaseous petroleum products.

[0056] In the embodiment of the present invention, the treating of the plastic material for converting the plastic material into gaseous petroleum products thermolysis of the molten plastic material in the least one reactor by indirectly heating the said plastic material and maintaining at a temperature in a range of 400 °C to 450 °C for about up to 7 hours for thermally cracking the plastic material to obtain the gaseous petroleum products.

[0057] In one embodiment of the present invention, the thermolysis is carried out in the first thermolysis reactor of the said at least one thermolysis reactor for about up to 7 hours.

[0058] In another embodiment of the present invention, the thermolysis is carried out in the second thermolysis reactor of the said at least one thermolysis reactor for about up to 7 hours.

[0059] In one embodiment of the present invention, the plurality of reactors includes the recovery reactor for heating densified molten plastic with filler material discharged from the said at least one thermolysis reactor.

[0060] In the embodiment of the present invention, the densified molten plastic with filler material remained in the at least one thermolysis reactor during the thermolysis of the plastic material.

[0061] In the embodiment of the present invention, the said densified molten plastic with filler material is heated and maintained at the temperature in a range of about 450 °C - 500 °C for about 2.5 - 3 hours for thermally cracking the saiddensified molten plastic with filler material to obtain the gaseous petroleum products.

[0062] In one embodiment of the present invention, the system includes condensers that are operatively connected to the melting reactor, the thermolysis reactors and the recovery reactor.

[0063] In the embodiment of the present invention, the said condensers are adapted to receive the said gaseous petroleum products and condense the said gaseous petroleum products to obtain the liquified petroleum products.

[0064] In one embodiment of the present invention, the system includes a cooling system for supplying cooling to the said one or more condensers.

[0065] In one embodiment of the present invention, the system includes a heat generation system that includes a molten salt boiler for continuous combustion of the non-condensable gaseous for generating heat for operating plurality or reactors via the heated molten salt stream.

[0066] In the embodiment of the present invention, these non-condensable gaseous beings remained during the condensation of the said gaseous petroleum products.

[0067] This, along with the other aspects of the present invention and the various features of novelty that characterize the present disclosure, is pointed out with particularity.

[0068] For a better understanding of the present disclosure, its operating advantages, and the specified objective attained by its uses, reference should be made to the accompanying descriptive matter in which there are illustrated exemplary embodiments of the present invention.DESCRIPTION OF THE DRAWINGS

[0069] The advantages and features of the present invention will become better understood with reference to the following detailed description taken in conjunction with the accompanying drawings, in which:

[0070] Fig. 1A illustrates a flowchart representing a process for converting plastic material (waste plastic) into liquified petroleum products, according to various embodiments of the present invention;

[0071] Fig. IB illustrates a flowchart representing an exemplary process for converting the plastic material (waste plastic) into the liquified petroleum products, according to various embodiments of the present invention;

[0072] Fig. 2 A illustrates a schematic diagram representing a system for carrying out the process of Fig. 1A, according to various embodiments of the present invention;

[0073] Fig. 2B illustrates a schematic diagram representing a system for carrying out the conversion process of waste plastic material to liquified petroleum products, according to various embodiments of the present invention;

[0074] Fig. 3 illustrates a flowchart representing a pre-treatment of plastic material before the process of Fig. 1A, according to various embodiments of the present invention;

[0075] Fig. 4 illustrates a schematic diagram representing a system for carrying out the cleaning of plastic material, according to various embodiments of the present invention;

[0076] Fig. 5A illustrates a schematic diagram representing a heating system for treating the plastic material, according to various embodiments of the present invention; and

[0077] Fig. 5B illustrates a flowchart representing steps for heating of the plastic material, according to various embodiments of the present invention.

[0078] Like numerals denote like elements throughout the figures.DESCRIPTION OF THE INVENTION

[0079] The exemplary embodiments described herein detail for illustrative purposes are subjected to many variations. It should be emphasized, however, that the present invention is not limited to as disclosed.

[0080] It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

[0081] Specifically, the following terms have the meanings indicated below.

[0082] The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.

[0083] The terms “having”, “comprising”, “including”, and variations thereof signify the presence of a component.

[0084] The inventive aspects of the invention along with various components and engineering involved will now be explained with reference to Figs. 1 A-5B herein.

[0085] The present invention relates to the field of processing waste plastic materials into petroleum products. More particularly, the present invention discloses a process for converting plastic material (waste plastic) into liquified petroleum products.

[0086] “Liquified petroleum products” herein refers to one or more of the following: liquefied petroleum gas, gasoline, jet fuel, kerosene, diesel, and combinations thereof.

[0087] Referring to Fig. 1A, an exemplary process (100) for converting plastic material into liquified petroleum products is explained with reference to a flowchart.

[0088] The “plastic material” herein refers to a material consisting of a wide range of synthetic or semi-synthetic organic compounds.

[0089] In an exemplary embodiment of the present invention, the said plastic material may include waste materials such as industrial waste.

[0090] The process (100) starts with step (10) which involves feeding the said plastic material from a material storage (180) into a melting reactor (50) via a feeding system (170) (refer Fig. 1A).

[0091] In an exemplary embodiment of the present invention, the process (100) includes pre-treatment of the said plastic material prior to the feeding of the plastic material into the material reactor (50) (refer Figs. 3 & 4).

[0092] In the embodiment of the present invention, the said pre-treatment of the plastic material includes cleaning the said plastic material via conventional techniques used in cleaning the said plastic material (refer to Figs. 3 & 4).

[0093] In the exemplary embodiment of the present invention, the said plastic material is received from a raw plastic dump yard (160) which is transported via a loading system (162) via a feed hopper (170a), for cleaning the said plastic material, as shown in step (2) (refer to Figs. 2 A, 3 & 4).

[0094] In one embodiment of the present invention, the said plastic material is being conveyed to a de-dusting device (110) via one or more conveying devices (140) (refer to Figs. 2 A, 3 & 4).

[0095] More particularly, the said plastic material is being cleaned in the dedusting device (110) including a plurality of screens for removing sand or any other foreign particles of size below 15-20 mm, as shown in step (3) (refer to Figs. 2A, 3 & 4).

[0096] In an exemplary embodiment of the present invention, the dust generated during the screening process are transported to a dust plant (112) and are blown out by a blower (114) (refer to Figs. 2A & 4).

[0097] Thereafter, the said plastic material is conveyed in one or more conveying devices (140) installed with magnetic separators (120) to remove ferromagnetic particles from the said plastic material, and thereafter, non-magnetic particles are removed manually, as shown in steps (4) and (5) respectively (refer to Figs. 3 & 4).

[0098] In various embodiments of the present invention, foreign particles, sand particles, ferromagnetic particles, and non-magnetic materials are transferred and collected in a garbage container (116), as shown in steps (3a), (4a), and (5a) (refer to Figs. 2 A, 3 & 4).

[0099] In one embodiment of the present invention, the cleaned plastic material is conveyed to a shredding device (125) via the conveying devices (140) such as a belt conveyor at step (6) (refer to Figs. 3 & 4).

[0100] Further, the pre -treatment of the plastic material includes shredding the said cleaned plastic material into the shredding device (125) at step (7) (refer to Figs. 3 & 4).

[0101] In an exemplary embodiment of the present invention, dust generated during the shredding of the said plastic material is extracted via the dust plant (112), at step (7a) (refer to Figs. 3 & 4).

[0102] Subsequently, the process (100) involves palletizing the said shredded plastic material to form pallets / briquettes of the said plastic material of uniform sizes in a palletizing device (130), and storing the said pallets, at steps (8) & (9) respectively (refer to Figs. 3 & 4).

[0103] In another embodiment of the present invention, the pallets / briquettes of the said plastic material are conveyed to a bagging unit (132) to bag these briquettes in jumbo bags.

[0104] Again, referring to Fig. 1A, at step (12), the process involves melting of the said plastic material in a melting reactor (50) of the plurality of the reactors (50, 60, 70, 80) (refer to Figs. 1A & 2A).

[0105] In the embodiment of the present invention, the melting is carried out by operating the melting reactor (50) at a temperature in a range of 350 °C to 400 °C continuously to obtain molten plastic material.

[0106] Further, at step (14), the process (100) involves discharging the said molten plastic material into at least one thermolysis reactor (60, 70) of the plurality of reactors (50, 60, 70, 80) (refer to Figs. 1A & 2A).

[0107] In an embodiment of the present invention, the said molten plastic material is discharged in a predefined amount via at least one valve (60a) or (70a) into the said at least one thermolysis reactor (60, 70) (refer to Figs. 2A-2B & 5A).

[0108] In the exemplary embodiment of the present invention, after receiving the required amount, the discharge from the melting reactor (50) is stopped by closing the valve (60a) or (70a).

[0109] In the embodiment of the present invention, the feeding of the plastic material to the melting reactor (50) may continue even during the feeding of the molten plastic material to the said at least one thermolysis reactor (60, 70).

[0110] At step (16), the process (100) further includes thermolysis of the plastic material in the at least one thermolysis reactor (60, 70) by indirectly heating the said molten plastic material at a temperature in a range of 400 °C to 450 °C for about up to 7 hours for thermally cracking the plastic material to obtain the gaseous petroleum products (refer to Figs. 1 A, 2A-2B & 5A).

[0111] “Thermolysis” refers to the chemical decomposition of a substance or thermal cracking of hydrocarbons in the petroleum industry.

[0112] “Gaseous petroleum products” herein refers to hydrocarbon gaseous compounds that form as a result of the cracking of the polymers in the molten state during thermolysis.

[0113] In the embodiment of the present invention, the gaseous compounds having lower carbon content typically vary from Cl to C30.

[0114] In one embodiment of the present invention, firstly, the thermolysis of the molten plastic material is carried out in a first thermolysis reactor (60) for about up to 7 hours, at step (16a) (refer to Fig. IB).

[0115] In the embodiment of the present invention, the said molten plastic material is discharged in the said first thermolysis reactor (60) by opening a first valve (60a) prior to the thermolysis, as shown in step (14a) (refer to Fig. IB).

[0116] In the embodiment of the present invention, once the predefined amount (required height of the molten plastic bed is achieved) of the molten plastic material is discharged into the first thermolysis reactor (60), the discharge from the melting reactor (50) is stopped by closing the first valve (60a) at step (15a) (refer to Fig. IB).

[0117] In the exemplary embodiment of the present invention, after about 4 hours of the above-mentioned step, the second valve (70a) is opened, and the said molten plastic material is discharged in the second thermolysis reactor (70) from the said melting reactor (50), at step (14b) (refer to Figs. IB, 2A-2B & 5A).

[0118] In the embodiment of the present invention, once the predefined amount (required height of the molten plastic bed is achieved) of the molten plastic material is discharged into the second thermolysis reactor (70), the discharge from the melting reactor (50) is stopped by closing the second valve (70a) at step (15b) (refer to Fig. IB).

[0119] In the embodiment of the present invention, the thermolysis of the molten plastic material is carried out in the second thermolysis reactor (70) for about up to 7 hours (refer to Figs. 2A-2B & 5 A).

[0120] More specifically, the thermolysis is carried out in the first thermolysis reactor (60) and the second thermolysis reactor (70) one after the other, thereby allowing continuous treatment of the molten plastic material for converting the said material to the gaseous petroleum products.

[0121] Again, referring to Fig. 1A, at step (22), the process (100) involves directing the said gaseous petroleum products to one or more condensers (90) (refer to Figs. 1A, IB & 2A-2B).

[0122] In the embodiment of the present invention, the said gaseous products are transported due to the pressure generating during conversion of molten plastic material into gaseous state.

[0123] Further, at step (24), the process (100) involves condensing the gaseous petroleum products in the condensers (90) to convert the said gaseous petroleum products into liquified petroleum products (refer to Figs. 1 A, IB & 2A-2B).

[0124] In an exemplary embodiment of the present invention, about 80% - 85% of the gaseous compounds get condensed at room temperature to form liquified petroleum products such as diesel or petrol.

[0125] In the embodiment of the present invention, about 10% - 12% of the gaseous compounds may not get condensed at room temperature.

[0126] In the embodiment of the present invention, these non-condensable gases consist of methane and are pumped into a heat generation system (150) which generates the heat required for operating the plurality of the reactors (50, 60, 70, 80) and other components required to carry out the process (100).

[0127] More specifically, these non-condensable gases are transported / pumped to a molten salt boiler (152) of the heat generation system (150), as shown in step (38) (refer to Figs. 2 A & 5A-5B).

[0128] In the embodiment of the present invention, these non-condensable gases get combusted continuously with supplied combustion air (directed by a blower (118)) in the molten salt boiler (152), for the generation of heat for operating the plurality of reactors (50, 60, 70, 80) via heated molten salt stream, at step (32) (refer to Figs. 1, 2A & 5A-5B).

[0129] More specifically, the said high-temperature molten salt stream is fed in a controlled manner to the said plurality of reactors (50, 60, 70, 80) for indirectly heating the plastic material at the required temperature, at step (34) (refer to Figs. 1, 2A & 5A-5B).

[0130] The molten salts are usable at higher temperatures compared to other existing heating techniques. The molten salts also have thermal stability even at higher temperatures and good heat transfer properties, which may reduce overall operating costs.

[0131] The adaptation of the molten salt as a heat transfer source may also lead to an increase the efficiency due to lack of change in the phase of the fluid during continued operation.

[0132] In another embodiment of the present invention, the heating may also be provided by other indirect heating technologies.

[0133] In the embodiment of the present invention, the quantum of noncondensable gases generated is sufficient for continued operation without adding fuel (oil, or gas) externally.

[0134] In an exemplary embodiment of the present invention, the process (100) is initiated with either gas, oil, or solid fuel.

[0135] In an exemplary embodiment of the present invention, molten salt is stored in a molten salt storage tank (154) after passing through each reactor of the plurality of reactors (50, 60, 70, 80), at step (36) (refer to Figs. 2A & 5A-5B).

[0136] The said boiler (152) is designed in such a way that it minimizes the formation of Nitrogen Oxides (NOx).

[0137] In another embodiment of the present invention, the thermolysis step also results in the production of excess gases that are disposed of through a chimney (156) after the combustion of these gases in a combustion chamber (158). These gases consist of Carbon dioxide (CO2), Water (H2O), and Nitrogen (N).

[0138] Coming back to step (16), the thermolysis of the molten plastic material may also result in molten plastic with fillers that remain in the reactors (60, 70) in dense slurry form (refer to Figs. 1 A & 2A).

[0139] In the embodiment of the present invention, the densified molten plastic with filler material is discharged from the said at least one thermolysis reactor (60, 70) into a recovery reactor (80) of the plurality of reactors (50, 60, 70, 80) by opening a third valve (80a), at step (18) (refer to Figs. 1A, 2A & 5).

[0140] More specifically, the densified molten plastic with filler material is discharged into the recovery reactor (80) from the first reactor (60) and the second reactor (70) respectively, at steps (18a) & (18b) (refer to Fig. IB).

[0141] More specifically, when the thermolysis process is being carried out in the thermolysis reactors (60, 70), the density of the remaining molten plastic materials in said reactors (60, 70) is gradually increased due to the filler materials mixed in the molten plastic materials.

[0142] Continuing the thermolysis process for the molten plastic materials in the thermolysis reactors (60, 70) until a last drop of the liquid is not economical due to the volume of molten plastics is too low and the thermolysis reactors (60, 70) are bigger in size, thereby resulting in wastage of more energy and time.

[0143] To overcome the said losses of energy and time, the densified molten plastic materials in the thermolysis reactors (60, 70) are discharged to the recovery reactor (80) alternatively from each thermolysis reactor (60, 70).

[0144] In an exemplary embodiment of the present invention, the densified molten plastic with filler material is discharged into the recovery reactor (80) from the first reactor (60) and the second reactor (70), thereby maintaining a time gap of about 4 hours.

[0145] In the embodiment of the present invention, the said densified molten plastic with filler material is heated and maintained in the said recovery reactor (80) at a temperature of about 450 °C - 500 °C for about 2.5- 3 hours for continuouslythermally cracking the said densified molten plastic with filler material to obtain the gaseous petroleum products at step (20) (refer to Figs. 1A, 2A & 5A).

[0146] More specifically, the molten plastic materials are heated to the said range of temperature and maintained to allow obtaining the gaseous petroleum products until the last drop of the liquid and allowing the filler materials to allow remaining in dry and solid form.

[0147] In an exemplary embodiment of the present invention, firstly the densified molten plastic with filler material (received from the said first thermolysis reactor (60)) is heated at step (20a), which is followed by heating of the densified molten plastic (received from the said second thermolysis reactor (70), at step (20b) (refer to Fig. 5B).

[0148] In another exemplary embodiment of the present invention, the densified molten plastic with filler material (received from the said first thermolysis reactor (60) is heated and complete its cycle before receiving densified molten plastic material from second thermolysis reactor (70)).

[0149] Thereafter, the said gaseous petroleum products are transported to the condensers (90) as shown in above-mentioned step (22) of the process (100) (refer to Figs. 1A & 2A).

[0150] Subsequently, the process (100) follows step (24) to condense the said gaseous petroleum products to produce the liquified petroleum products.

[0151] Further, the ready to use liquified petroleum products are stored in an oil storage system (210) for transportation.

[0152] In various embodiments of the present invention, the liquified oil produced after the carrying out the process (100), is conducted with various tests for extracting the chemical or physical properties of the said produced oil.EXAMPLE

[0153] Cleaning waste plastics aggregated from various sources is cleaned to remove sand, stone, metallic components, fabric, rubber, leather, etc. The cleaned waste plastics are then shredded and pelletized, and the pellets are stored. Those pellets which can be introduced as plastic pellets, are fed to the melting reactor (50) at a controlled feed rate. When the process is being continued, the bed height of the molten plastics in the melting reactor (50) is controlled. The feed rates and feeding durations of plastic pellets to the melting reactor (50) depends upon the bed height of molten plastics in the reactor (50). The temperature of the melting reactor is controlled in the range of about 350 degrees Celsius to 400 degrees Celsius by varying the flow rate of molten salt passing through the reactor. An operating pressure in the reactor is almost atmospheric pressure. The bed height of the thermolysis reactors is controlled when molten plastics are transferred to the thermolysis reactor (60) from the melting reactor. When one thermolysis reactor is considered, it’s a batch process, however the total process is operated with multiple thermolysis reactors (60, 70, or any additional thermolysis reactors), and it’s a continuous process. Similar to the melting reactor, thermolysis reactor / s is / are also heated with molten salt which is passing through the reactor / s (50, 60, 70, 80). The temperature in the thermolysis reactor (60) is in the range of about 400 degrees Celsius to 450 degrees Celsius. The operating pressure of the thermolysis reactor (60) is slightly higher than the atmospheric pressure. The low level of the bed of molten plastics in the thermolysis reactor (60) is reached, and the molten salt flow through the reactor is stopped. At this moment, the liquid of molten plastics in the reactor is more viscous due to the higher concentration of filler materials accumulated from the fed plastics. While an agitator of the reactor is being operated, the densified liquid is discharged to the recovery reactor (80) via the second valve (70a). The thermolysis process in the first thermolysis reactor (60) is led by approximately 3 - 4 hours from the second thermolysis reactor (70) to operate system with a single recovery reactor (80). Due to the offset of processes in two thermolysis reactors (60, 70), the overall process is moving continuously. The system is not limited to two thermolysis reactors and when the number of thermolysis reactors are increased, the number of recovery reactors are alsoincreased accordingly. The recovery reactor (80) is operated at the range of temperature of about 450 degrees Celsius to 500 degrees Celsius. The process is batch operated and the batch time is in the range of about 2.5 to 3 hours. One batch from the first thermolysis reactor (60) should be completed within the given period of time to get ready for the second batch from the second thermolysis reactor (70).The operating pressure of the recovery reactor (80) is slightly higher than the atmospheric pressure. All the solid materials accumulated in the molten plastics are accumulated in the recovery reactor (80) and are removed from the system after completion of evaporation of molten plastics. These accumulated solids are in dry condition. The evaporated gaseous petroleum products from reactors are arranged to go through the condensers (90) which are connected to each reactor. About 82 - 85% of the gaseous petroleum products are condensed to liquified petroleum products during condensing process. 10 - 15% of the gaseous petroleum products do not condense and the gases are used to heat generation at the molten salt boiler. The properties of liquified petroleum products so obtained is compared with respect to the existing diesel oil is shown in Table- 1 below:Table- 1

[0154] As shown in the table 1 above, the liquified petroleum product obtained by the process has comparable calorific value with lower ash content and sulfur content.

[0155] In one embodiment of the present invention, a system (1000) for carrying the process (100) of converting plastic material into liquified petroleum products is disclosed.

[0156] The system (1000) includes one or more cleaning devices (110, 120, 122) for cleaning the said plastic material (refer to Figs. 2 A & 4).

[0157] In the embodiment of the present invention, the cleaning devices (110, 120, 122) include a de-dusting device (110) for removing foreign particles of size below 15-20 mm (refer to Figs. 2A & 4).

[0158] The said cleaning devices further include at least one magnetic separator (120) installed at the said one or more conveying devices (140), for removing ferromagnetic particles.

[0159] In one embodiment of the present invention, one or more workers (122) are provided to manually remove non-magnetic particles from the said plastic material passing through the said one or more conveying devices.

[0160] In one embodiment of the present invention, the system (1000) further includes a shredding device (125) for shredding the said cleaned plastic material (refer to Figs. 2 A & 4).

[0161] In one embodiment of the present invention, the system (1000) includes a palletizing device (130) for palletizing the said shredded plastic material to form pallets of the said plastic material of uniform sizes.

[0162] In one embodiment of the present invention, the system (1000) includes the plurality of reactors (50, 60, 70, 80) that include the melting reactor (50) for melting the said plastic material (refer to Figs. 2 A & 5A).

[0163] In the embodiment of the present invention, the melting of the said plastic material is carried out by operating the melting reactor (50) at a temperature in a range of 350 °C to 400 °C to obtain and maintain a bed of molten plastic material.

[0164] In one embodiment of the present invention, the system (1000) includes the feeding system (170) to feed the said plastic material from a material storage (180) into the melting reactor (50) (refer to Fig. 2 A).

[0165] In one embodiment of the present invention, the said plurality of reactors (50, 60, 70, 80) includes at least one thermolysis reactor (60, 70) for treating the said plastic material for converting the plastic material into gaseous petroleum products (refer to Figs. 2 A & 5A).

[0166] In the embodiment of the present invention, the treating of the plastic material for converting the plastic material into the gaseous petroleum products thermolysis of the plastic material in the least one reactor (60, 70) by indirectly heating the said plastic material at a temperature in a range of 400 °C to 450 °C for about up to 7 hours for thermally cracking the plastic material to obtain the gaseous petroleum products (refer to Figs. 2 A & 5A).

[0167] In one embodiment of the present invention, the thermolysis is carried out in a first thermolysis reactor (60) of the said at least one thermolysis reactor (60, 70) for about 7 hours.

[0168] In another embodiment of the present invention, the thermolysis is carried out in a second thermolysis reactor (70) of the said at least one thermolysis reactor (60, 70) for about 7 hours (refer to Figs. 2A & 5A).

[0169] In one embodiment of the present invention, the plurality of reactors (50, 60, 70, 80) includes a recovery reactor (80) for heating densified molten plastic material discharged from the said at least one thermolysis reactor (60, 70).

[0170] In the embodiment of the present invention, the densified molten plastic material remained in the reactors (60, 70) during the thermolysis of the plastic material.

[0171] In the embodiment of the present invention, the said densified molten plastic material is heated at a temperature in a range of 450 °C - 5000C for about 2.5 - 3 hours for thermally cracking the said uncracked plastic material to obtain the gaseous petroleum products.

[0172] In one embodiment of the present invention, the system (1000) includes the condensers (90) that are operatively connected to the reactors (60, 70) and the recovery reactor (80) (refer to Figs. 2A & 5A).

[0173] In the embodiment of the present invention, the said condensers (90) are adapted to receive the said gaseous petroleum products and condense the said gaseous petroleum products to obtain the liquified petroleum products.

[0174] In one embodiment of the present invention, the system (1000) includes a cooling system (200) for supplying cooling to the said one or more condensers (90).

[0175] In one embodiment of the present invention, the system (1000) includes a heat generation system (150) that includes a molten salt boiler (152) for continuous combustion of the non-condensable gases for generating heat for operating the plurality of reactors (50, 60, 70, 80) via the heated molten salt stream (refer to Figs. 2A & 5A).

[0176] In the embodiment of the present invention, these non-condensable gaseous beings remained during the condensation of the said gaseous petroleum products.Advantageous effects of the present invention

[0177] Therefore, the process of the present invention is clean and environmentally friendly, has low energy consumption and cost, high oil yield, and stable oil quality, solves the worldwide technical problem of easy coking in the reactor. Further, the process and system of the present invention convert waste plastics into high-quality liquified petroleum products without a need for catalyst / s.

[0178] Furthermore, the process and system for converting waste plastic into vax- free liquified petroleum products even at low temperatures. In addition, the process and system of the present invention utilize heating so that the reactors may operate at an optimum temperature range for converting the waste plastic into the liquified petroleum products more efficiently.

[0179] Further, the plurality of reactors of the present invention works so that the said process for converting waste plastic into liquified petroleum products is carried out in a continuous manner. Moreover, the process of the present invention utilizes the non-condensable gases along with molten salt to provide heating to operate the process of converting the waste plastic material into liquified petroleum products without the need of external thermal fuel source.

[0180] In a nutshell, the process and system of the present invention overcomes the drawbacks discussed above and provides an efficient and cost-effective way for converting plastic material into liquified petroleum products.

[0181] It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

[0182] The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously, many modifications and variations are possible in light of the above teaching.

[0183] Further, the embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated.

Claims

[00184] CLAIMS:

1. A process for converting plastic material such as waste plastics into liquified petroleum products, the process comprising: feeding a predefined amount of the plastic material into a plurality of reactors; treating the said plastic material in the plurality of reactors to convert the plastic material into gaseous petroleum products; directing the said gaseous petroleum products into one or more condensers; and condensing the gaseous petroleum products in the one or more condensers to convert the said gaseous petroleum products into liquified petroleum products, wherein, the treating of the plastic material for converting the plastic material into the gaseous petroleum products comprises, thermolysis of the plastic material in at least one thermolysis reactor of the plurality of reactors comprises indirectly heating the said plastic material by operating the said at least one thermolysis reactor at a temperature in a range of 400 °C to 450 °C for thermally cracking the plastic material to obtain the gaseous petroleum products, and wherein the said at least one thermolysis reactor being operated by heat generated by utilizing non-condensable gaseous remains obtained during the condensation of the said gaseous petroleum products, thereby leading to the indirect heating of the said plastic material.

2. The process as claimed in claim 1, wherein the plastic material is being fed from a material storage into the plurality of the reactors via a feeding system.

3. The process as claimed in claim 1 comprising pre-treatment of the plastic material prior to the feeding of the plastic material into the plurality of reactors.

4. The process as claimed in claim 3, wherein the pre-treatment of the plastic material comprises,cleaning the said plastic material via one or more cleaning devices, shredding the said cleaned plastic material into a shredding device, palletizing the said shredded plastic material to form pallets of the said plastic material of uniform sizes in a palletizing device, and wherein the said plastic material is transported to the shredding device and the said palletizing device via one or more conveying devices.

5. The process as claimed in claim 4, wherein the said cleaning of the plastic material comprises, removing foreign particles of size below 15-20 mm via a de-dusting device, removing ferromagnetic particles via one or more magnetic separators that are installed in the said one or more conveying devices, and manually removing non-magnetic particles from the said plastic material passing through the said one or more conveying devices.

6. The process as claimed in claim 1 comprising melting of the said plastic material in a melting reactor prior to the thermolysis of the said plastic material, wherein the melting of the said plastic material is carried out by operating the melting reactor at a temperature in a range of 350 °C to 400 °C continuously to obtain molten plastic material and maintain a bed of molten plastic material.

7. The process as claimed in claim 6, wherein the said molten plastic material is discharged in the predefined amount into the said at least one thermolysis reactor, wherein the feeding of the material is controlled by one of a first valve or second valve, wherein the predefined amount of the plastic material comprises amount up to which the molten plastic material reaches a required height.

8. The process as claimed in claim 1, wherein the thermolysis is carried out in a first thermolysis reactor of the said at least one thermolysis reactor for about up to 7 hours.

9. The process as claimed in claim 1, wherein the thermolysis is carried out in a second thermolysis reactor of the said at least one thermolysis reactor for about up to 7 hours.

10. The process as claimed in claim 1 comprising discharging the remaining densified molten plastic with fillers from the said at least one thermolysis reactor into a recovery reactor of the plurality of reactors, wherein the densified molten plastic being remained in the at least one thermolysis reactor during the thermolysis of the plastic material.

11. The process as claimed in claim 10, wherein the said densified molten plastic is indirectly heated in the said recovery reactor at a temperature of about 450 °C - 500 °C for about 2.5 - 3 hours for thermally cracking the said densified molten plastic material to obtain the gaseous petroleum products.

12. The process as claimed in claim 1, wherein the indirect heating being generated by a heat generation system by utilizing the said non-condensable gaseous, wherein the said heat generation system comprises a molten salt boiler for continuous combustion of the non-condensable gases, with supplied combustion air, for generating heat for operating the plurality of reactors via molten salt stream.

13. The process as claimed in claim 1 comprising supplying cooling to the said one or more condensers via a cooling system.

14. A system for converting plastic material such as waste plastics into liquified petroleum products, the system comprising: a plurality of reactors comprising at least one thermolysis reactor, the said plurality of reactors is adapted for, receiving the said plastic material, treating the said plastic material for converting the plastic material into gaseous petroleum products, one or more condensers operatively connected to the at least one thermolysis reactor, the said one or more condensers are adapted to, receive the said gaseous petroleum products, and condense the said gaseous petroleum products to obtain liquified petroleum products, wherein,the treating of the plastic material for converting the plastic material into the gaseous petroleum products comprises, thermolysis of the plastic material in at least one thermolysis reactor of the plurality of reactors comprises indirectly heating the said plastic material by operating the said at least one thermolysis reactor at a temperature in a range of 400 °C to 450 °C for thermally cracking the plastic material to obtain the gaseous petroleum products, and wherein the said at least one thermolysis reactor being operated by heat generated by utilizing non-condensable gaseous remains obtained during the condensation of the said gaseous petroleum products, thereby leading to the indirect heating of the said plastic material.

15. The system as claimed in claim 14 comprising a feeding system to feed the said plastic material from a material storage into the plurality of reactors.

16. The system as claimed in claim 14 comprising, one or more cleaning devices for cleaning the said plastic material prior to the feeding of the plastic material into the plurality of reactor, a shredding device for shredding the said cleaned plastic material, a palletizing device for palletizing the said shredded plastic material to form pallets of the said plastic material of uniform sizes, wherein the said plastic material is transported to the shredding device and the said palletizing device via one or more conveying devices.

17. The system as claimed in claim 16, wherein the one or more cleaning devices comprise, a de-dusting device for removing foreign particles of size below 15-20 mm, at least one magnetic separator installed in the said one or more conveying device, for removing ferromagnetic particles, and one or more workers to manually remove non-magnetic particles from the said plastic material passing through the said one or more conveying devices.

18. The system as claimed in claim 14, wherein the plurality of reactors comprises a melting reactor for melting the said plastic material prior to the thermolysis of the said plastic material, wherein the melting of the said plastic material being carried out by operating the melting reactor at a temperature in a range of 350 °C to 400 °C continuously to obtain molten plastic material and maintain a bed of molten plastic material.

19. The system as claimed in claim 14, wherein the at least one thermolysis reactor comprises a first thermolysis reactor for carrying out thermolysis for about up to 7 hours.

20. The system as claimed in claim 14, wherein at least one thermolysis reactor comprises a second thermolysis reactor for carrying out thermolysis for about up to 7 hours.

21. The system as claimed in claim 14, wherein the plurality of reactors comprises a recovery reactor for heating densified molten plastic material discharged from the at least one thermolysis reactor, wherein the uncracked plastic material being remained in the at least one thermolysis reactor during the thermolysis of the plastic material.

22. The system as claimed in claim 21, wherein the said densified molten plastic material is heated at a temperature of about 450 °C - 500 °C for about 2.5 - 3 hours for thermally cracking the said densified molten plastic material to obtain the gaseous petroleum products.

23. The system as claimed in claim 14 comprising a heat generation system comprises a molten salt boiler for continuous combustion of the non-condensable gases, with supplied combustion air, for generating heat for operating the plurality of reactors via heated molten salt stream.

24. The system as claimed in claim 14 comprising a cooling system for supplying cooling to the said one or more condensers.

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