Hydrocarbon feedstock derived from mixed plastic waste

Abstract

The present invention relates to a process and a system for producing a hydrocarbon feedstock comprising oligomeric products derived from waste plastic materials wherein such a hydrocarbon feedstock is particularly suitable for fluid catalytic cracking. The invention further relates to such hydrocarbon feedstocks and related properties thereof.

Description

[0001] Related applications for cross-reference

[0002] This application claims priority to European Patent Application No. 22202344, filed on October 19, 2022. Technical field

[0003] The present invention relates to a method and system for producing a hydrocarbon feedstock that includes oligomeric products derived from waste plastic materials and is particularly suitable for fluid catalytic cracking. The present invention further relates to such a hydrocarbon feedstock and its related properties. Background art

[0004] Fluid catalytic cracking (FCC) is one of the methods for obtaining gasoline and other high-value chemicals such as ethylene and propylene from hydrocarbon feedstocks. With the continuous fluctuations in gasoline prices that affect the world economy, industrial practitioners and government agencies have been exploring options for producing gasoline and other high-value chemicals from reliable and economic feedstock sources. One of the challenges faced by operators of FCC units is the need to increase the degree of conversion of hydrocarbon feedstocks to obtain high-value chemical products while keeping the degree of coke formation at an acceptable level, so that the FCC process has greater operating efficiency and is more cost-effective.

[0005] One possible solution could be to partially replace expensive feeds such as vacuum gas oil with relatively abundant and available materials, thus reducing the cost of feedstock procurement. In addition, it is desirable to produce high-value chemicals such as propylene and butene at a desired productivity while controlling the degree of coke formation. Managing coke formation is particularly beneficial because catalyst regeneration and productivity can be maintained at an effective level. As an additional consideration, FCC operators typically face the challenge of dealing with hydrocarbon feeds that have an undesirably large amount of inorganic materials and chlorine. Unless such substances are removed from the hydrocarbon feed, the presence of such substances tends to have an adverse effect on FCC operation.

[0006] On the other hand, an issue that seems unrelated to the challenges of operating an FCC unit is the matter of dealing with waste plastics. Most waste plastics are diverted to landfills or incinerated, and fewer products are diverted for recycling. Over the years, as regulations and taxes on landfills have increased, the percentage of post-consumer waste recycled or incinerated for energy recovery has gradually increased, making it increasingly difficult to dispose of waste plastics through landfills.

[0007] Some viable technologies for treating plastic waste can be technologies based on the thermal cracking or catalytic cracking of plastic waste, as these technologies allow for the treatment of mixtures of different types of plastics without the need for separation by polymer type, which produces hydrocarbons suitable for the production of high-value chemicals.

[0008] In the past, thermal cracking has been studied at the laboratory and pilot plant levels for the treatment of plastic waste. However, conventional thermal cracking methods produce low-quality and unstable hydrocarbons with a wide boiling point range, making this method inefficient and uneconomical for waste plastic treatment. Among the different methods for catalytic cracking of waste plastics, there is fluid catalytic cracking (FCC).

[0009] However, when using an FCC unit to treat plastic waste, there are still certain challenges: (1) the handling of solid plastic waste is not always easy, (2) plastic waste may not be soluble in vacuum gas oil (VGO), which is commonly used as the feed for FCC units, and (3) the plastic waste stream may contain chlorine and other inorganic material contents far exceeding the feed specifications of the FCC unit, (4) the catalyst system in the FCC unit may not be able to handle polymer materials with large molecular weights.

[0010] Most conventional chemical recycling methods for plastic waste involve pyrolyzing the plastic to produce pyrolysis oil (also known as "pyoil"). As conventionally understood by this term, this involves complete or near-complete depolymerization of the plastic. Using a pyrolysis oil-based feed is an option to address the drawbacks associated with handling polymer materials with large molecular weights in an FCC unit. However, pyrolyzing waste plastics to produce pyrolysis oil is an energy-intensive method that involves decomposing the polymers present in the waste plastic to a weight-average molecular weight of less than 400 g / mol. The pyrolysis process not only has a high energy requirement but also emits undesirable greenhouse gases and other undesirable gases under certain conditions. In addition, pyrolysis oil contains aromatics, olefins, and other unsaturated substances, which may lead to an increase in the formation of coke during FCC operation. Moreover, using pyrolysis oil and other pyrolysis products reduces carbon efficiency because the production of pyrolysis oil from plastic waste generates a large amount of gas and coke due to harsh conditions.

[0011] EP3878926A1 discloses a suspension comprising (1) vacuum gas oil, and (2) 1-15 wt% of plastic particle powder, which comprises particles that can be obtained by cryogenic grinding of waste polyethylene and / or waste polypropylene and have a size of less than 500 microns. Although the technical solution proposed in this patent application is promising, there is still room for improving the properties of the feedstock suitable for FCC operation.

[0012] Therefore, one of the objectives of the present invention is to provide a hydrocarbon feed stream that is at least partially derived from waste plastic materials and is suitable for use as a feedstock for fluid catalytic cracking (FCC) to produce high-value chemicals at a desired conversion rate and yield while reducing the degree of coke formation.

[0013] Another object of the present invention is to improve the conversion of products and reduce coke formation in a fluid catalytic cracking process relative to conventional FCC feeds such as VGO. A further object of the present invention is to produce a hydrocarbon feed suitable for an FCC unit with minimum energy consumption. Yet another object of the present invention is to use a fluid catalytic cracking process to produce one or more cracked hydrocarbon products in an energy-saving manner with high conversion and minimum coke formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] For a more complete understanding, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:

[0015] Figure 1 is a schematic diagram illustrating an embodiment of the present invention, in which the method involves the step of diluting the obtained product stream (J) with an additional atmospheric vacuum gas oil feed (AV) in a blending unit (E), and subsequently obtaining a feed stream (H).

[0016] Figure 2 is a schematic diagram illustrating an embodiment of the present invention, in which the method involves the step of feeding the obtained product stream (J) into a separation unit (C), and then blending it with an additional atmospheric vacuum gas oil feed (AV) in a blending unit (E) to obtain a hydrocarbon feed stream (H).

[0017] Figure 3 is a schematic diagram illustrating an embodiment of the present invention, in which the method involves supplying a waste plastic feed stream (W) and an atmospheric vacuum gas oil feed (V) to a dechlorination unit (B) to form a stream (D), which is then introduced into a thermal cracking unit (A) to obtain a product stream (J). The schematic diagram further illustrates that the product stream (J) is subsequently diluted with an additional atmospheric vacuum gas oil feed (AV) in a blending unit (E) to subsequently obtain a hydrocarbon feed stream (H).

[0018] Figure 4 is a schematic diagram illustrating an embodiment of the present invention, in which the method involves using a dechlorination unit (B), a separation unit (C) and obtaining a hydrocarbon feed stream (H). Subsequently, the hydrocarbon feed stream (H) is introduced into a fluid catalytic cracker (FCC).

[0019] Figures 5-7 The illustration shows that when a hydrocarbon feed stream (R1 - R6) containing an oligomer product (O1) from the example section is used as the feed in fluid catalytic cracking, compared with a conventional FCC feed containing only atmospheric vacuum gas oil (VGO), using such a feed results in a reduction in coke at a constant conversion.

[0020] Figures 8-10The figure shows that when a hydrocarbon feed stream (R1 - R6) containing an oligomer product (O1) from the Examples section is used as a feed in fluid catalytic cracking, compared to a conventional FCC feed containing only vacuum gas oil (VGO), using such a feed results in an increase in the yield of propylene (C 3 - olefins) at a constant conversion rate.

[0021] Figures 11-13 The figure shows that when a hydrocarbon feed stream (R1 - R6) containing an oligomer product (O1) from the Examples section is used as a feed in fluid catalytic cracking, compared to a conventional FCC feed containing only vacuum gas oil (VGO), using such a feed results in an increase in the yield of butene (C 4 - olefins) at a constant conversion rate. Detailed Description

[0022] The object of the present invention is achieved at least in part by a method for producing a hydrocarbon feed stream (H), which comprises the following steps:

[0023] (i) providing a waste plastic feed stream (W) containing one or more polymers (P1);

[0024] (ii) feeding the waste plastic feed stream (W) and optionally a vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J), wherein the product stream (J) contains an oligomer product (O1) derived from the one or more polymers (P1), and further wherein the oligomer product (O1) has a weight average molecular weight as determined by gel permeation chromatography of ≥ 1,000 g / mol and ≤ 20,000 g / mol, preferably ≥ 1,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 10,000 g / mol, preferably ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol; and

[0025] (iii) blending the product stream (J) with an additional vacuum gas oil feed (AV) to obtain the hydrocarbon feed stream (H).

[0026] Preferably, the oligomer product (O1) content of the hydrocarbon feed stream (H) is > 0 and ≤ 20.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0027] Optionally, in another embodiment, the present invention relates to a method for producing a hydrocarbon feed stream (H), which comprises the following steps:

[0028] (i) Provide a waste plastic feed stream (W) comprising one or more polymers (P1);

[0029] (ii) Feed the waste plastic feed stream (W) and optionally a vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J), wherein the product stream (J) comprises an oligomeric product (O1) derived from the one or more polymers (P1), and further wherein the oligomeric product (O1) has a weight average molecular weight as determined by gel permeation chromatography of ≥8,000 g / mol and ≤18,000 g / mol, preferably ≥9,000 g / mol and ≤18,000 g / mol, preferably ≥12,000 g / mol and ≤18,000 g / mol; and

[0030] (iii) Blend the product stream (J) with an additional vacuum gas oil feed (AV) and obtain the hydrocarbon feed stream (H), preferably wherein the oligomeric product (O1) content of the hydrocarbon feed stream (H) is >0 and ≤20.0 wt% relative to the total weight of the hydrocarbon feed stream (H).

[0031] Optionally, in another embodiment, the present invention relates to a method for producing a hydrocarbon feed stream (H) comprising the steps of:

[0032] (i) Provide a waste plastic feed stream (W) comprising one or more polymers (P1);

[0033] (ii) Feed the waste plastic feed stream (W) and optionally a vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J), wherein the product stream (J) comprises an oligomeric product (O1) derived from the one or more polymers (P1), and further wherein the oligomeric product (O1) has a weight average molecular weight as determined by gel permeation chromatography of ≥12,000 g / mol and ≤18,000 g / mol; and

[0034] (iii) Blend the product stream (J) with an additional vacuum gas oil feed (AV) and obtain the hydrocarbon feed stream (H), preferably wherein the oligomeric product (O1) content of the hydrocarbon feed stream (H) is >0 and ≤20.0 wt% relative to the total weight of the hydrocarbon feed stream (H).

[0035] Preferably, the oligomeric product (O1) content of the hydrocarbon feed stream (H) is ≥2.0 wt% and ≤10.0 wt%, and the oligomeric product (O1) comprised in the product stream (J) has a weight average molecular weight as determined by gel permeation chromatography of ≥12,000 g / mol and ≤18,000 g / mol.

[0036] Advantageously, as can be seen in the embodiments of the present invention, the blending of the product stream (J) with an additional atmospheric vacuum gas oil feed (AV) results in a hydrocarbon feed stream (H) which, when subjected to fluid catalytic cracking, is converted with a higher conversion rate into commercially valuable hydrocarbons. Accordingly, the present inventors have proposed the combination of a hydrocarbon feed such as VGO with an oligomer product stream as a means of chemically recycling plastics, which enables the production of cyclic polymers and gasoline components with a high conversion rate. Considering that a typical refinery processes approximately 4000 kta (thousand tons per year) of VGO, blending up to 20 wt% of the oligomer product derived from waste plastics would allow the processing of up to approximately 800 kta of plastics.

[0037] As a further advantage, the VGO also serves as a "solvent" for the product stream (J) containing the oligomer product (O1). Although fluid catalytic cracking is exemplified in the present invention, the hydrocarbon feed stream (H) is also suitable for other types of hydrocarbon cracking such as steam cracking.

[0038] The term "atmospheric vacuum gas oil" or "VGO" is a commonly used and well-known term in petroleum refining and is a composition of a complex combination of hydrocarbons produced by subjecting the residue from the atmospheric distillation of crude oil to vacuum distillation.

[0039] Although the atmospheric vacuum gas oil feed (AV) is referred to as an additional atmospheric vacuum gas oil feed, it should be understood that it may be the first use of the atmospheric vacuum gas oil in the process if the atmospheric vacuum gas oil is optionally absent in the thermal cracking step.

[0040] The weight average molecular weight can be measured by any suitable gel permeation chromatography method. Preferably, the weight average molecular weight is determined by gel permeation chromatography in accordance with ASTM D5296-11, using polystyrene standards.

[0041] Oligomer product (O1)

[0042] The weight average molecular weight of the oligomer product (O1) is higher than that of the atmospheric vacuum gas oil and typical pyrolysis oils and pyrolysis oil derivatives. In order to measure the weight average molecular weight of the oligomer product (O1) by gel permeation chromatography, the contribution from the atmospheric vacuum gas oil is not considered.

[0043] As can be understood by those skilled in the art, in gel permeation chromatography, the higher molecular weight components are eluted first. Accordingly, the atmospheric vacuum gas oil fraction should be the last fraction to be eluted and its contribution is not considered when determining the weight average molecular weight of the oligomer product.

[0044] Without wishing to be bound by any particular theory, the inventors believe that by thermal cracking to reduce the weight average molecular weight, the resulting oligomeric products can readily diffuse into the catalyst pores in the FCC unit. On the other hand, the inventors believe that reducing the polymer particle size by cryogenic grinding generally does not reduce the weight average molecular weight of the polymer, and thus the ease with which the ground polymer particles enter the catalyst pores in the FCC unit is generally lower than that of the oligomeric products, which in turn affects the hydrocarbon conversion in the FCC process.

[0045] Preferably, the product stream (J) is substantially free of pyrolysis oil or pyrolysis products. Preferably, the product stream (J) contains 0.0 wt% of pyrolysis oil or pyrolysis products.

[0046] Importantly, the weight average molecular weight of the oligomeric product (O1) is higher than that of the pyrolysis oil or the product derived from the pyrolysis of waste plastics. Pyrolysis oil (including pyrolysis oil made from plastic feedstocks) is generally understood to have a weight average molecular weight of less than 1000 g / mol, more likely less than 600 g / mol, even more likely less than 400 g / mol and more likely about 200 g / mol, and energy-intensive processes would be required to produce it, which results in increased capital expenditure and operating expenditure for producing such low molecular weight substances.

[0047] In addition, there may also be some carbon efficiency gains because producing pyrolysis oil from plastic waste generates a large amount of gas and coke (the pyrolysis oil yield of pyrolysis is usually only ~70%). When producing oligomers, the yield is significantly higher (>90%) because gas generation is minimized due to less severe conditions.

[0048] In addition, such pyrolysis oil samples have a high content of unsaturated products (such as aromatics), which may not be suitable for producing hydrocarbons in the FCC unit with high conversion and low coke formation. Pyrolysis oil made from plastics is an almost completely depolymerized product, with gas and light oil as products and almost no remaining oligomeric components, having a correspondingly low weight average molecular weight.

[0049] To demonstrate, commercially available pyrolysis oil samples from five suppliers were analyzed by simulated distillation (Simdist) gas chromatography. The Simdist method produced the boiling point distribution of the commercially available pyrolysis oil samples. Since pyrolysis oil is usually mainly paraffins (~50 - 60 wt%), the inventors can here correlate the Simdist data with the boiling points of paraffins to estimate the average molecular weight of the pyrolysis oil samples, as shown in Table 1 below. It should be noted that the presence of aromatics, olefins and other unsaturated substances in the pyrolysis oil will tend to reduce the average molecular weight compared to the estimated values shown herein. Therefore, using the paraffin boiling points as a basis for estimating the average molecular weight of pyrolysis oil samples may provide a higher molecular weight than the actual molecular weight of the pyrolysis oil samples, and the actual average molecular weight is very likely to be lower than those shown in Table 1.

[0050] Table 1

[0051]

[0052] Advantageously, the conversion to obtain the oligomeric product (O1) requires a lower energy demand than methods involving pyrolysis, which depolymerize the polymeric material to a significantly greater extent than practiced in the present invention. Thus, the thermal cracking method to obtain the oligomeric product (O1) is not only energy efficient and less environmentally hazardous, but also makes the method economically efficient in terms of lower capital and operating costs.

[0053] Some depolymerization of the plastic is necessary to obtain the oligomeric product (O1), since cracking a hydrocarbon feed stream (H) comprising the oligomeric product (O1) having a high weight average molecular weight in an FCC unit would present compatibility and processing problems, as is the case for most plastics.

[0054] Although the weight average molecular weight of the oligomeric product (O1) can be as low as 1,000 g / mol, in order to fully realize the advantages of the present invention, it is preferred to use an oligomeric product having a higher weight average molecular weight, preferably ≥2,000 g / mol, preferably ≥8,000 g / mol, preferably ≥9,000 g / mol, preferably ≥12,000 g / mol, but this would be even more preferred after considering the amount of plastic to be processed.

[0055] It should be understood that as the weight average molecular weight of the oligomeric product (O1) in the hydrocarbon feed stream (H) increases, it may be necessary to reduce the wt% of the oligomeric product (O1) in the hydrocarbon feed stream (H) in order to facilitate processing of the hydrocarbon feed stream (H) in the FCC unit.

[0056] Preferably, the product stream (J) comprises >90.0 wt%, preferably >95.0 wt%, preferably >98.0 wt%, preferably >99.0 wt%, preferably >99.5 wt%, preferably 100.0 wt% of the oligomeric product (O1) relative to the total weight of the product stream (J).

[0057] In one aspect of the present invention, the method of the present invention comprises the steps of: supplying a waste plastic feed stream (W) and a vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) and form a product stream (J). Preferably, >80.0 wt%, more preferably >90.0 wt%, most preferably 100 wt% of the waste plastic feed stream (W) is thermally cracked to form the product stream (J).

[0058] The waste plastic feed stream (W) and the vacuum gas oil feed stream (V) can be blended together to form a thermal cracking stream, which is then introduced into the thermal cracking unit (A). The waste plastic feed stream (W) and the vacuum gas oil feed stream (V) can be blended in an amount such that the thermal cracking stream has > 80 wt%, more preferably > 90 wt% of the thermal cracking stream.

[0059] In an alternative embodiment, the waste plastic feed stream (W) and the vacuum gas oil feed stream (V) can be introduced separately into the thermal cracking unit (A) and then cracked under thermal cracking conditions.

[0060] Reference Figure 1 , the schematic diagram illustrates an embodiment of the present invention, which relates to the steps of supplying a waste plastic feed stream (W) and a vacuum gas oil feed stream (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) and form a product stream (J). The product stream (J) is then diluted in a blending unit (E) with an additional vacuum gas oil feed (AV) to obtain a hydrocarbon feed stream (H).

[0061] Although the additional vacuum gas oil feed (AV) is referred to as an additional vacuum gas oil feed, it should be understood that if the vacuum gas oil is optionally absent in the thermal cracking step, it can be the first use of the vacuum gas oil in the process.

[0062] The blending unit (E) can be a mixing chamber where the product stream (J) and the additional vacuum gas oil feed (AV) are blended. Optionally, the blending unit (E) can be a piping system capable of combining the product stream (J) with the additional vacuum gas oil feed (AV).

[0063] Hydrocarbon feed stream (H)

[0064] The product stream (J) obtained from the thermal cracking unit (A) is blended with the additional vacuum gas oil feed (AV) to obtain a hydrocarbon feed stream (H) having a sufficient amount of vacuum gas oil and oligomeric products (O1) suspended in the vacuum gas oil. Preferably, the content of oligomeric products (O1) in the hydrocarbon feed stream (H) is ≤ 20.0 wt%, preferably ≤ 15.0 wt%, preferably ≤ 10.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0065] Preferably, the content of oligomeric products (O1) in the hydrocarbon feed stream (H) is ≥ 0.5 wt% and ≤ 20.0 wt%, preferably ≥ 0.5 wt% and ≤ 15.0 wt%, preferably ≥ 0.5 wt% and ≤ 10.0 wt%, preferably ≥ 1.0 wt% and ≤ 8.0 wt%, preferably ≥ 2.0 wt% and ≤ 10.0 wt%, preferably ≥ 2.0 wt% and ≤ 5.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0066] Preferably, the content of vacuum gas oil in the hydrocarbon feed stream (H) is ≥ 80.0 wt%, preferably ≥ 85.0 wt%, preferably ≥ 90.0 wt% based on the total weight of the hydrocarbon feed stream (H). Preferably, the content of vacuum gas oil in the hydrocarbon feed stream (H) is ≥ 80.0 wt% and ≤ 99.5 wt%, preferably ≥ 85.0 wt% and ≤ 99.5 wt%, preferably ≥ 90.0 wt% and ≤ 99.5 wt%, preferably ≥ 92.0 wt% and ≤ 99.0 wt%, preferably ≥ 90.0 wt% and ≤ 98.0 wt%, preferably ≥ 95.0 wt% and ≤ 98.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0067] The additional VGO feed serves as a solvent for the oligomer product (O1). If the content of the oligomer product (O1) in the hydrocarbon feed stream (H) > 20.0 wt%, the solubility of the oligomers will be insufficient for further processing in the FCC unit. On the other hand, if the amount of the oligomer product (O1) < 0.5 wt%, the desired conversion rate to cracking products through the FCC operation will not be at the desired level.

[0068] In addition, it is estimated that for blends with > 20.0 wt% of the oligomer product (O1), a significant degree of depolymerization is required, which eliminates the commercial cost savings of partial depolymerization.

[0069] The hydrocarbon feed stream (H) is particularly suitable for a fluid catalytic cracking unit (FCC). Preferably, the hydrocarbon feed stream (H) contains:

[0070] (a) an atomic chlorine content < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight; and / or

[0071] (b) a total inorganic material content ≤ 1.0 wt%, preferably ≤ 0.8 wt%, preferably ≤ 0.5 wt%, preferably 0.0 wt% based on the total weight of the hydrocarbon feed stream (H); and / or

[0072] (c) the oligomer product (O1) has a weight average molecular weight ≥ 1,000 g / mol and ≤ 20,000 g / mol, ≥ 1,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 10,000 g / mol, preferably ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol as determined by gel permeation chromatography.

[0073] Preferably, the hydrocarbon feed stream (H) comprises:

[0074] (a) an atomic chlorine content < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight; and / or

[0075] (b) a total inorganic materials content ≤ 1.0 wt% based on the total weight of the hydrocarbon feed stream (H), preferably ≤ 0.8 wt%, preferably ≤ 0.5 wt%, preferably 0.0 wt%; and / or

[0076] (c) the weight-average molecular weight of the oligomeric product (O1) as determined by gel permeation chromatography ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol.

[0077] Preferably, the hydrocarbon feed stream (H) comprises:

[0078] (a) an atomic chlorine content < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight; and

[0079] (b) a total inorganic materials content ≤ 0.5 wt% based on the total weight of the hydrocarbon feed stream (H), preferably 0.0 wt%; and

[0080] (c) a weight-average molecular weight ≥ 12,000 g / mol and ≤ 18,000 g / mol as determined by gel permeation chromatography.

[0081] Preferably, the weight-average molecular weight of the oligomeric product (O1) as determined by gel permeation chromatography ≥ 2,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 10,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol.

[0082] Atomic chlorine can be measured by any suitable method, preferably determined according to ASTM UOP 779-08.

[0083] The present inventors have found that for a hydrocarbon feed stream (H), when used as a feedstock for a fluid catalytic cracker (FCC), it is desirable to have a high feedstock conversion while minimizing the extent of coke formation. The present inventors have found that, compared to a conventional FCC feedstock consisting essentially of vacuum gas oil (VGO), a hydrocarbon feed stream (H) at a similar conversion level produces a higher yield of polyolefins. This is particularly surprising since typically a high feed conversion leads to an increase in coke formation. Advantageously, the present invention now enables a person skilled in the art not only to increase the efficiency of the fluid catalytic cracking process but also to obtain a process for the effective use of waste plastic materials.

[0084] In one aspect of the present invention, the present invention relates to a hydrocarbon feed stream (H) obtainable by the process of the present invention. Preferably, the hydrocarbon feed stream (H) comprises:

[0085] (a) an atomic chlorine content of < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight; and / or

[0086] (b) a total inorganic materials content of ≤ 1.0 wt% based on the total weight of the hydrocarbon feed stream (H), preferably ≤ 0.8 wt%, preferably ≤ 0.5 wt%, preferably 0.0 wt%; and / or

[0087] (c) the oligomeric product (O1) having a weight average molecular weight as determined by gel permeation chromatography of ≥ 1,000 g / mol and ≤ 20,000 g / mol, preferably ≥ 1,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 10,000 g / mol, preferably ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol.

[0088] Preferably, the hydrocarbon feed stream (H) comprises (i) a vacuum gas oil content of ≥ 80.0 wt% and ≤ 99.5 wt%, preferably ≥ 85.0 wt% and ≤ 99.5 wt%, preferably ≥ 90.0 wt% and ≤ 99.5 wt%, preferably ≥ 92.0 wt% and ≤ 99.0 wt%, preferably ≥ 90.0 wt% and ≤ 98.0 wt%, preferably ≥ 95.0 wt% and ≤ 98.0 wt%, based on the total weight of the hydrocarbon feed stream (H), and (ii) an oligomer product (O1) content of ≥ 0.5 wt% and ≤ 20.0 wt%, preferably ≥ 0.5 wt% and ≤ 15.0 wt%, preferably ≥ 0.5 wt% and ≤ 10.0 wt%, preferably ≥ 1.0 wt% and ≤ 8.0 wt%, preferably ≥ 2.0 wt% and ≤ 10.0 wt%, preferably ≥ 2.0 wt% and ≤ 5.0 wt%, based on the total weight of the hydrocarbon feed stream (H).

[0089] Preferably, the hydrocarbon feed stream (H) obtainable by the process of the present invention comprises:

[0090] (a) an atomic chlorine content of < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight; and

[0091] (b) a total inorganic materials content of ≤ 1.0 wt%, preferably ≤ 0.8 wt%, preferably ≤ 0.5 wt%, preferably 0.0 wt%, based on the total weight of the hydrocarbon feed stream (H); and

[0092] (c) the oligomer product (O1) having a weight average molecular weight as determined by gel permeation chromatography of ≥ 1,000 g / mol and ≤ 20,000 g / mol, preferably ≥ 1,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 10,000 g / mol, preferably ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol; and

[0093] (d) a vacuum gas oil content of ≥ 80.0 wt% and ≤ 99.5 wt%, preferably ≥ 85.0 wt% and ≤ 99.5 wt%, preferably ≥ 90.0 wt% and ≤ 99.5 wt%, preferably ≥ 92.0 wt% and ≤ 99.0 wt%, preferably ≥ 90.0 wt% and ≤ 98.0 wt%, preferably ≥ 95.0 wt% and ≤ 98.0 wt%, based on the total weight of the hydrocarbon feed stream (H); and

[0094] (e) The content of the oligomeric product (O1) is ≥ 0.5 wt% and ≤ 20.0 wt%, preferably ≥ 0.5 wt% and ≤ 15.0 wt%, preferably ≥ 0.5 wt% and ≤ 10.0 wt%, preferably ≥ 1.0 wt% and ≤ 8.0 wt%, preferably ≥ 2.0 wt% and ≤ 10.0 wt%, preferably ≥ 2.0 wt% and ≤ 5.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0095] In another aspect of the present invention, the present invention relates to one or more cracked hydrocarbon products obtainable by a method comprising the following steps:

[0096] (i) Providing a waste plastic feed stream (W) comprising one or more polymers (P1);

[0097] (ii) Supplying the waste plastic feed stream (W) and optionally a vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J), wherein the product stream (J) comprises an oligomeric product (O1) derived from the one or more polymers (P1), and wherein the oligomeric product (O1) has a weight average molecular weight as determined by gel permeation chromatography of ≥ 1,000 g / mol and ≤ 20,000 g / mol, ≥ 1,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 10,000 g / mol, preferably ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol;

[0098] (iii) Blending the product stream (J) with an additional vacuum gas oil feed (AV) to obtain the hydrocarbon feed stream (H); and

[0099] (iv) Introducing the hydrocarbon feed stream (H) into a fluid catalytic cracking unit (FCC) that operates under conditions suitable for cracking the hydrocarbon feed stream (H) in the presence of a catalyst to obtain a product stream (FP) comprising one or more cracked hydrocarbon products.

[0100] Preferably, the content of the oligomeric product (O1) in the hydrocarbon feed stream (H) is ≤ 20.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0101] In another aspect of the present invention, the present invention relates to one or more cracked hydrocarbon products obtainable by a method comprising the following steps:

[0102] (i) Providing a waste plastic feed stream (W) comprising one or more polymers (P1);

[0103] (ii) Supply the waste plastic feed stream (W) and optionally the vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J), wherein the product stream (J) comprises an oligomeric product (O1) derived from the one or more polymers (P1), and wherein the oligomeric product (O1) has a weight average molecular weight of ≥12,000 g / mol and ≤18,000 g / mol as determined by gel permeation chromatography;

[0104] (iii) Blend the product stream (J) with an additional vacuum gas oil feed (AV) to obtain a hydrocarbon feed stream (H); and

[0105] (iv) Introduce the hydrocarbon feed stream (H) into a fluid catalytic cracking unit (FCC) that operates under conditions suitable for cracking the hydrocarbon feed stream (H) in the presence of a catalyst to obtain a product stream (FP) comprising one or more cracked hydrocarbon products.

[0106] Preferably, the content of the oligomeric product (O1) in the hydrocarbon feed stream (H) is ≤20.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0107] Atomic chlorine can be measured by any suitable method, preferably as determined according to ASTM UOP 779-08. When obtained by the process of the present invention, the hydrocarbon feed stream (H) has a suitable content of inorganic materials, a suitable atomic chlorine content, and an oligomeric product with a suitable weight average molecular weight. The inventors believe that the low molecular weight oligomeric products present in the hydrocarbon feed stream (H) can improve catalytic conversion in the FCC unit to produce olefins and other high value chemicals while controlling the degree of coke formation. The content of inorganic materials and atomic chlorine is maintained within desired limits to prevent poisoning of the catalyst system in the FCC unit and to prevent corrosion of equipment by hydrochloric acid generated from the chlorine-containing feed.

[0108] Waste plastic material

[0109] The waste plastic feed stream (W) comprising the polymer (P1) can be at least partially derived from waste plastic materials. Non-limiting examples of waste plastic materials include mixed plastic waste (MPW), waste plastic films, agricultural waste, waste generated from building materials, post-industrial waste, post-consumer waste, and waste from materials recycling facilities (MRF).

[0110] The vacuum gas oil feed (V) can be any distillate product obtained by vacuum distilling the atmospheric distillation residue of a crude oil feedstock. The term distillate product means any product that is not the residue or bottom product of a vacuum distillation. A suitable vacuum gas oil has an API gravity of 19 - 23 and an initial boiling point of 255 - 300 °C, a 10% boiling point of 343 - 393 °C, a 50% boiling point of 438 - 465 °C, a 90% boiling point of 500 - 560 °C, and a final boiling point of 527 - 582 °C. The API gravity can be measured by any suitable method, such as ASTM D4052. The boiling point of the vacuum gas oil can be measured by any suitable method, such as ASTM D1160.

[0111] The one or more polymers (P1) can be at least one polymer selected from the following: polyethylene, polypropylene, PS (polystyrene); PVC (polyvinyl chloride); PET (polyethylene terephthalate); PUT (polyurethane), PP&A fiber (polyphthalamide fiber), polyvinylidene chloride, ABS (acrylonitrile - butadiene - styrene), nylon, aromatic polyamide, fluorinated polymer, and combinations thereof. Preferably, the one or more polymers (P1) are at least one polymer selected from polypropylene or polyethylene.

[0112] Preferably, the polymer (P1) is polyethylene. The polyethylene can be low - density polyethylene (LDPE), linear low - density polyethylene (LLDPE), high - density polyethylene (HDPE). Preferably, the polymer (P1) is low - density polyethylene (LDPE). Preferably, the polymer (P1) is low - density polyethylene (LDPE) derived from waste plastic films. Preferably, the one or more polymers (P1) are a mixture of polyethylene and polypropylene.

[0113] The weight - average molecular weight of the one or more polymers (P1) as determined by gel permeation chromatography can be ≥40,000 g / mol and ≤500,000 g / mol, preferably ≥50,000 g / mol and ≤200,000 g / mol, preferably ≥50,000 g / mol and ≤150,000 g / mol.

[0114] Thermal cracking unit (A)

[0115] The oligomer product (O1) is derived from the one or more polymers (P1). The one or more polymers (P1) depolymerize under thermal cracking conditions to form an oligomer product (O1) with a weight - average molecular weight lower than that of the one or more polymers (P1).

[0116] The thermal cracking unit (A) can operate at a temperature of ≥350°C and ≤500°C, preferably ≥370°C and ≤450°C, more preferably ≥375°C and ≤400°C, and a feed residence time of ≥10.0 minutes and ≤80.0 minutes, preferably ≥15.0 minutes and ≤60.0 minutes, more preferably ≥25.0 minutes and ≤60.0 minutes.

[0117] Preferably, the thermal cracking unit (A) can operate at a temperature of ≥350°C and ≤400°C and a feed residence time of ≥25.0 minutes and ≤60.0 minutes. Preferably, the thermal cracking unit (A) can operate at a temperature of ≥375°C and ≤400°C and a feed residence time of ≥40.0 minutes and ≤60.0 minutes.

[0118] Preferably, the thermal cracking of one or more polymers (P1) is carried out at a temperature of 375°C and ≤400°C and a feed residence time of ≥40.0 minutes and ≤60.0 minutes. Under such operating conditions, the polymer (P1) is only partially depolymerized.

[0119] The expression "feed residence time" as used herein refers to the residence time of the waste plastic feed stream (W) and optionally the vacuum gas oil feed (V) in the thermal cracking unit (A). The thermal cracking unit (A) is configured to operate in such a way that when the feed residence time is long, the feed containing the waste plastic feed stream (W) and optionally the vacuum gas oil feed (V) experiences a lower cracking temperature. On the other hand, when the feed residence time is short, the feed containing the waste plastic feed stream (W) and optionally the vacuum gas oil feed (V) experiences a higher cracking temperature.

[0120] Inorganic materials

[0121] Before blending the product stream (J) with additional vacuum gas oil feed (AV), the product stream (J) can be passed through a separation unit (C) such that the total inorganic material content of the product stream (J) blended with the additional vacuum gas oil feed (AV) is ≤1.0 wt%, preferably ≤0.8 wt%, preferably ≤0.5 wt%, preferably 0.0 wt% based on the total weight of the product stream (J). The separation unit (C) is configured to remove inorganic materials from the product stream (J) such that the feed stream (H) has a desirably low inorganic material content. The inorganic materials are preferably kept at a low level to prevent possible deactivation of the catalyst in the FCC unit.

[0122] Non-limiting examples of inorganic materials include calcium carbonate (CaCO 3 )), inorganic antioxidants, light stabilizers, polymerization catalyst residues, titanium dioxide, and silicon-based materials, which are additives commonly present in polymers.

[0123] The separation unit (C) can be any suitable separation device, such as a centrifuge or a membrane separation unit. The centrifuge can operate at a temperature of about 150 °C or lower, while the membrane separation unit can operate at a temperature of about 400 °C or lower.

[0124] Reference Figure 2 , in some embodiments of the present invention, the method involves supplying a waste plastic feed stream (W) and a vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J). The product stream (J) is passed through a separation unit (C) and then blended with an additional vacuum gas oil feed (AV) in a blending unit (E) to obtain a hydrocarbon feed stream (H).

[0125] Dechlorination

[0126] The atomic chlorine content of the waste plastic feed stream (W) supplied to the thermal cracking unit (A) is < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight. Atomic chlorine can be measured by any suitable method, preferably determined according to ASTM UOP 779-08.

[0127] In this case, if the chlorine content in the waste plastic feed stream (W) is high, the waste plastic feed stream (W) can be passed through a dechlorination unit (B) to reduce the atomic chlorine content in the waste plastic feed stream (W).

[0128] Preferably, in some embodiments of the present invention, the method of the present invention includes the step of passing the waste plastic feed stream (W) and optionally the vacuum gas oil feed (V) through a dechlorination unit (B) before being supplied to the thermal cracking unit (A), so that the atomic chlorine content of the waste plastic feed stream (W) supplied to the thermal cracking unit (A) is < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight.

[0129] Preferably, the method includes the steps of feeding both the waste plastic feed stream (W) and the vacuum gas oil feed (V) into a dechlorination unit (B) to obtain a stream (D); and supplying the stream (D) to the thermal cracking unit (A), wherein the atomic chlorine content of the stream (D) is < 50.0 ppm by weight, preferably < 40.0 ppm by weight, preferably < 30.0 ppm by weight, preferably < 10.0 ppm by weight, preferably < 0.5 ppm by weight, preferably 0.0 ppm by weight. The stream (D) is obtained from the dechlorination unit (B) and contains the waste plastic feed stream (W) and the vacuum gas oil feed (V).

[0130] The dechlorination unit is configured to receive a stream having a high concentration of atomic chlorine. For example, the atomic chlorine content of the waste plastic feed stream (W) introduced into the dechlorination unit (B) can be <6,000 ppm by weight, preferably <2,000 ppm by weight, preferably <1,000 ppm by weight, preferably <500 ppm by weight, preferably <200 ppm by weight. Atomic chlorine can be measured by any suitable method, preferably determined according to ASTM UOP 779-08.

[0131] The dechlorination unit (B) can be operated at a temperature of ≥250 °C and ≤400 °C, preferably ≥275 °C and ≤325 °C and a feed residence time of ≥10.0 minutes and ≤80.0 minutes, preferably ≥15.0 minutes and ≤60.0 minutes.

[0132] Reference Figure 3 , in some embodiments of the present invention, the method involves supplying a waste plastic feed stream (W) and a vacuum gas oil feed (V) to the dechlorination unit (B) to form a stream (D). Subsequently, the stream (D) is introduced into the thermal cracking unit (A) to obtain a product stream (J). The product stream (J) is further diluted with an additional vacuum gas oil feed (AV) in the blending unit (E) to obtain a hydrocarbon feed stream (H).

[0133] Fluid catalytic cracker (FCC)

[0134] In some aspects of the present invention, the method further comprises the step of introducing the hydrocarbon feed stream (H) into a fluid catalytic cracking unit (FCC), which is operated under conditions suitable for cracking the hydrocarbon feed stream (H) in the presence of a catalyst to obtain a product stream (FP) comprising one or more cracked hydrocarbon products.

[0135] Optionally, the present invention relates to a method for producing one or more cracked hydrocarbon products, which comprises the following steps:

[0136] (i) providing a waste plastic feed stream (W) comprising one or more polymers (P1);

[0137] (ii) Supply the waste plastic feed stream (W) and optionally the vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J), wherein the product stream (J) contains oligomeric products (O1) derived from the one or more polymers (P1), and further wherein the oligomeric products (O1) have a weight average molecular weight as determined by gel permeation chromatography of ≥ 1,000 g / mol and ≤ 20,000 g / mol, ≥ 1,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 2,000 g / mol and ≤ 10,000 g / mol, preferably ≥ 8,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol;

[0138] (iii) Blend the product stream (J) with an additional vacuum gas oil feed (AV) to obtain a hydrocarbon feed stream (H); and

[0139] (iv) Introduce the hydrocarbon feed stream (H) into a fluid catalytic cracking unit (FCC) that operates under conditions suitable for cracking the hydrocarbon feed stream (H) in the presence of a catalyst to obtain a product stream (FP) containing one or more cracked hydrocarbon products.

[0140] Preferably, the oligomeric product (O1) content of the hydrocarbon feed stream (H) is ≤ 20.0 wt% based on the total weight of the hydrocarbon feed stream (H).

[0141] Preferably, the oligomeric product (O1) content of the hydrocarbon feed stream (H) is ≥ 0.5 wt% and ≤ 20.0 wt% based on the total weight of the hydrocarbon feed stream (H), preferably ≥ 0.5 wt% and ≤ 15.0 wt%, preferably ≥ 0.5 wt% and ≤ 10.0 wt%, preferably ≥ 1.0 wt% and ≤ 8.0 wt%, preferably ≥ 2.0 wt% and ≤ 5.0 wt%.

[0142] The fluid catalytic cracking unit (FCC) can operate at a catalyst:oil weight ratio of ≥ 3:1 to ≤ 10:1 and a temperature of ≥ 450 °C and ≤ 750 °C, preferably ≥ 500 °C and ≤ 650 °C.

[0143] During the fluid catalytic cracking process, the reaction time of the feed in contact with the catalyst is > 15 seconds and < 75 seconds, preferably > 45 seconds and < 65 seconds. The pressure can be maintained at atmospheric pressure.

[0144] The expression "catalyst:oil weight ratio" represents the ratio of the weight of the catalyst to the amount of feedstock (hydrocarbon feed stream (H)) introduced into the fluid catalytic cracking unit for cracking.

[0145] The catalyst can be an equilibrium catalyst (E-CAT) and can include at least one of the following: USY zeolite, X zeolite, mordenite, faujasite, nanocrystalline zeolite, MCM mesoporous material, SBA-15, silica-aluminum phosphate, gallium phosphate, titanium phosphate, ZSM-5 zeolite, RE-Y zeolite, RE-USY zeolite, and CREY zeolite.

[0146] The cracked hydrocarbon products are selected from ethylene, propylene, C 4 -C 30 hydrocarbons and C 6 -C 30 aromatics, gasoline, LPG, diesel, heavy oil, dry gas. Preferably, at a catalyst:oil weight ratio of 4.5, the hydrocarbon feed stream (H) is converted to cracked hydrocarbon products at a conversion rate of at least >73.0%.

[0147] Preferably, at a catalyst:oil weight ratio of 6.0, the hydrocarbon feed stream (H) is converted to cracked hydrocarbon products at a conversion rate of at least >75.0%. Preferably, at a catalyst:oil weight ratio of 9.1, the hydrocarbon feed stream (H) is converted to cracked hydrocarbon products at a conversion rate of at least >76.0%.

[0148] As used herein, the term "conversion rate" can be determined as follows: ((total weight of dry gas + LPG + gasoline products obtained from the fluid catalytic cracking unit) / total weight of hydrocarbon feed stream (H)) × 100.

[0149] In the calculation, the amount of coke formed is not included. Dry gas contains C 1 -C 2 hydrocarbons. Gasoline contains light naphtha (which includes C 5 -C 6 hydrocarbons with a boiling point of 30-90 °C) and heavy naphtha (which includes C 6 -C 12 hydrocarbons with a boiling point of 90-200 °C).

[0150] Thus, in one aspect of the present invention, the present invention relates to the use of a hydrocarbon feed stream (H) as a feedstock to improve the product conversion rate in a fluid catalytic cracking process. As used herein, the term "product conversion" means using fluid catalytic cracking to convert into one or more cracked hydrocarbons.

[0151] Reference Figure 4, in some embodiments of the present invention, the method of the present invention comprises the following steps: (a) introducing a waste plastic feed stream (W) and a vacuum gas oil feed (V) into a dechlorination unit (B) to obtain a stream (D); (b) introducing the stream (D) into a thermal cracking unit (A) to obtain a product stream (J); (c) feeding the product stream (J) into a separation unit (C); (d) blending the stream obtained in step (c) with an additional vacuum gas oil feed (AV) in a blending unit (E) to obtain a hydrocarbon feed stream (H). Then the hydrocarbon feed stream (H) is fed into a FCC unit (FCC) and processed.

[0152] System

[0153] In one aspect of the present invention, the present invention relates to a system adapted to produce a hydrocarbon feed stream (H). Preferably, the system comprises:

[0154] (a) A thermal cracking unit (A) configured to receive a waste plastic feed stream (W) and optionally a vacuum gas oil (VGO) feed (V) to produce a product stream (J);

[0155] (b) Optionally, a dechlorination unit (B), wherein the dechlorination unit (B) is in fluid communication with the thermal cracking unit (A), and wherein the dechlorination unit is located upstream of the thermal cracking unit (A), and wherein the dechlorination unit (B) is configured to receive the waste plastic feed stream (W) and optionally a vacuum gas oil (VGO) feed (V);

[0156] (c) A blending unit (E) configured to blend at least a portion of the product stream (J) obtained from the thermal cracking unit (A) and at least a portion of an additional vacuum gas oil feed (AV) to obtain a hydrocarbon feed stream (H); and

[0157] (d) Optionally, a separation unit (C), wherein the separation unit (C) is in fluid communication with the thermal cracking unit (A) and the blending unit (E), such that the separation unit (C) is located downstream of the thermal cracking unit (A) and upstream of the blending unit (E).

[0158] In one aspect of the present invention, the present invention relates to a system adapted to produce one or more cracked hydrocarbon products. Preferably, the system adapted to produce one or more cracked hydrocarbon products comprises:

[0159] (a) A thermal cracking unit (A) configured to receive a waste plastic feed stream (W) and optionally a vacuum gas oil (VGO) feed (V) to produce a product stream (J);

[0160] (b) Optionally, a dechlorination unit (B), wherein the dechlorination unit (B) is in fluid communication with the thermal cracking unit (A), and wherein the dechlorination unit is located upstream of the thermal cracking unit (A), and wherein the dechlorination unit (B) is configured to receive the waste plastic feed stream (W) and optionally a vacuum gas oil (VGO) feed (V);

[0161] (c) A blending unit (E), which is configured to blend at least a portion of the product stream (J) obtained from the thermal cracking unit (A) and at least a portion of an additional vacuum gas oil feed (AV) to obtain a hydrocarbon feed stream (H); and

[0162] (d) Optionally, a separation unit (C), wherein the separation unit (C) is in fluid communication with the thermal cracking unit (A) and the blending unit (E), such that the separation unit (C) is located downstream of the thermal cracking unit (A) and upstream of the blending unit (E); and

[0163] (e) A fluid catalytic cracking unit (FCC), wherein the fluid catalytic cracking unit (FCC) is configured to receive the hydrocarbon feed stream (H) and produce one or more cracked hydrocarbon products.

[0164] The operation of a commercial-scale fluid catalytic cracking unit (FCC) can be evaluated in an ACE (Advanced Catalyst Evaluation) unit, as described in the incorporated patent US6,069,012. The thermal cracking unit can be an autoclave reactor.

[0165] The following includes specific examples illustrating some embodiments of the present invention. The examples are for illustrative purposes only and are not intended to limit the present invention. It should be understood that the embodiments and aspects disclosed herein are not mutually exclusive, and these aspects and embodiments can be combined in any manner. Those skilled in the art will readily recognize that parameters can be changed or modified to produce substantially the same results.

[0166] Examples

[0167] Purpose: To evaluate the method of the present invention, six different hydrocarbon feed stream samples (R1 - R6) were produced. Subsequently, the performance of samples R1 - R6 as fluid catalytic cracking feeds was evaluated.

[0168] Materials and Apparatus: The following materials and apparatus were used (Table 2):

[0169] Table 2

[0170]

[0171] Method - Six hydrocarbon feed stream samples (R1 - R6) were prepared using the following protocol: Approximately 30 g of shredded black mulch film was placed into an autoclave (thermal cracking unit), which was then sealed and purged with nitrogen. The temperature was set to the desired operating set point, but the stirrer was not started until a temperature of 150 °C was reached (which is above the melting point of the LDPE polymer). At this point, the stirrer was turned on to 250 rpm and maintained at this value until the end of the run. Thermal cracking was carried out at three different temperatures (375 °C, 390 °C for 60 minutes each, and at 410 °C for 30 minutes) to obtain the product stream (J) for each of the six samples.

[0172] For each of the six samples, the entire contents of the reactor (product stream (J)) were removed and added to a conventional VGO at a level of 5.0 wt% or 10.0 wt% and mixed well at 200 °C, which produced the hydrocarbon feed stream samples shown in Table 2.

[0173] Samples R1 - R6 with a certain amount of oligomeric products suspended in VGO were taken as the samples of the present invention, while a feed stream containing only VGO was taken as a control (Table 3).

[0174] Table 3

[0175]

[0176] Samples R1 - R6 and the pure VGO sample were introduced into an ACE unit for fluid catalytic cracking. FCC tests were carried out in the ACE unit at 555 °C using an equilibrium catalyst containing ZSM - 5 catalyst and a specific catalyst / oil ratio. The reaction time of the feed w / catalyst was ~60 seconds. The catalyst / oil (C / O) ratio varied from 4 to 10, which was adjusted by changing the catalyst addition amount at a fixed feed injection rate. The tests were carried out at atmospheric pressure. The conversions of each sample at different catalyst / oil ratios were recorded and reported in Table 4 below:

[0177] Table 4

[0178]

[0179] It is clear from Table 3 that for each sample R1 - R6, at a given catalyst / oil ratio, the conversion is higher than that of the feed containing only pure VGO. For example, the conversion of sample R6 at a catalyst / oil ratio of 4.5 is approximately 4% higher than that of the feed stream containing only pure VGO (75.57 vs 72.95). Similarly, the conversion of sample R6 at a catalyst / oil ratio of 9.1 is approximately 3.2% higher than that of the feed stream containing only pure VGO (78.14 vs 75.72).

[0180] Figures 5-7 It is shown that when the hydrocarbon feed stream (R1-R6) of the present invention containing the oligomerization product (O1) is used as a feed in fluid catalytic cracking, compared with a conventional FCC feed containing only vacuum gas oil (VGO), using such a feed results in a reduction in coke at a constant conversion. For example, referring to Figure 5 , in the conversion range of 75-76%, pure VGO produced an undesirably higher coke formation than feeds R1 and R2.

[0181] In addition, Figures 8-10 It is clearly shown that when the hydrocarbon feed stream (R1-R6) containing the oligomerization product (O1) is used as a feed in fluid catalytic cracking, compared with a conventional FCC feed containing only vacuum gas oil (VGO), at a constant conversion, the yield of propylene (C 3 olefins) is significantly increased. For example, referring to Figure 8 , at a conversion of 74-78%, the amount of propylene produced by feeds R1 and R2 is greater than that of the feed containing pure VGO.

[0182] Figures 11-13 It is shown that when the hydrocarbon feed stream (R1-R6) containing the oligomerization product (O1) is used as a feed in fluid catalytic cracking, compared with a conventional FCC feed containing only vacuum gas oil (VGO), at a constant conversion, the yield of butene (C 4 olefins) is significantly increased. For example, referring to Figure 11 , at a conversion of 74-78%, the amount of C 4 olefins produced by feeds R1 and R2 is greater than that of the feed containing pure VGO.

[0183] The results obtained from the experiments clearly show that when the hydrocarbon feed (H) is used in the FCC unit, the degree of conversion to high-value products such as LPG and other gasoline is higher than that of a conventional FCC feed such as pure VGO, while minimizing coke formation.

Claims

1. A method for producing a hydrocarbon feed stream (H), comprising the following steps: (i) providing a waste plastic feed stream (W) comprising one or more polymers (P1); (ii) feeding the waste plastic feed stream (W) and optionally a vacuum gas oil feed (V) to a thermal cracking unit (A) to thermally crack at least a portion of the waste plastic feed stream (W) to form a product stream (J), wherein the product stream (J) comprises an oligomeric product (O1) derived from the one or more polymers (P1), and further wherein the oligomeric product (O1) has a weight average molecular weight as determined by gel permeation chromatography of ≥1,000 g / mol and ≤20,000 g / mol, preferably ≥1,000 g / mol and ≤15,000 g / mol, preferably ≥9,000 g / mol and ≤18,000 g / mol, preferably ≥12,000 g / mol and ≤18,000 g / mol; and (iii) blending the product stream (J) with an additional vacuum gas oil feed (AV) to obtain the hydrocarbon feed stream (H), preferably wherein the oligomeric product (O1) content of the hydrocarbon feed stream (H) is >0 and ≤20.0 wt% based on the total weight of the hydrocarbon feed stream (H).

2. The method according to claim 1, wherein the oligomeric product (O1) content of the hydrocarbon feed stream (H) is ≥0.5 wt% and ≤20.0 wt% based on the total weight of the hydrocarbon feed stream (H), preferably ≥0.5 wt% and ≤15.0 wt%, preferably ≥0.5 wt% and ≤10.0 wt%, preferably ≥1.0 wt% and ≤8.0 wt%, preferably ≥2.0 wt% and ≤10.0 wt%, preferably ≥2.0 wt% and ≤5.0 wt%.

3. The method according to any one of claims 1 - 2, wherein before blending the product stream (J) with the additional vacuum gas oil feed (AV), the product stream (J) is passed through a separation unit (C) such that the total inorganic material content of the product stream (J) blended with the additional vacuum gas oil feed (AV) is ≤1.0 wt% based on the total weight of the product stream (J), preferably ≤0.8 wt%, preferably ≤0.5 wt%, preferably 0.0 wt%.

4. The method according to any one of claims 1 - 3, wherein the hydrocarbon feed stream (H) comprises: (a) an atomic chlorine content <50.0 ppm by weight, preferably <40.0 ppm by weight, preferably <30.0 ppm by weight, preferably <10.0 ppm by weight, preferably <0.5 ppm by weight, preferably 0.0 ppm by weight, preferably determined according to ASTM UOP 779 - 08; and / or (b) a total inorganic material content ≤1.0 wt% based on the total weight of the hydrocarbon feed stream (H), preferably ≤0.8 wt%, preferably ≤0.5 wt%, preferably 0.0 wt%; and / or (c) The weight-average molecular weight of the oligomeric product (O1) determined by gel permeation chromatography is ≥1,000 g / mol and ≤20,000 g / mol, preferably ≥1,000 g / mol and ≤15,000 g / mol, preferably ≥2,000 g / mol and ≤15,000 g / mol, preferably ≥2,000 g / mol and ≤10,000 g / mol, preferably ≥8,000 g / mol and ≤18,000 g / mol, preferably ≥9,000 g / mol and ≤18,000 g / mol, preferably ≥12,000 g / mol and ≤18,000 g / mol.

5. The method according to any one of claims 1-4, wherein the content of the oligomeric product (O1) in the hydrocarbon feed stream (H) is ≥2.0 wt% and ≤10.0 wt%, and the product stream (J) contains the oligomeric product (O1) having a weight-average molecular weight of ≥12,000 g / mol and ≤18,000 g / mol determined by gel permeation chromatography.

6. The method according to any one of claims 1-5, wherein the one or more polymers (P1) are at least one polymer selected from the following: polyethylene, polypropylene, PS (polystyrene); PVC (polyvinyl chloride); PET (polyethylene terephthalate); PUT (polyurethane), PP&A fiber (polyphthalamide fiber), polyvinylidene chloride, ABS (acrylonitrile-butadiene-styrene), nylon, aramid, fluorinated polymer, and combinations thereof; preferably, the one or more polymers (P1) are at least one polymer selected from polypropylene or polyethylene.

7. The method according to any one of claims 1-6, wherein the thermal cracking unit (A) operates at a temperature of ≥350 °C and ≤500 °C, preferably at a temperature of ≥370 °C and ≤450 °C, preferably at a temperature of ≥375 °C and ≤400 °C and a feed residence time of ≥10.0 minutes and ≤80.0 minutes, preferably ≥15.0 minutes and ≤60.0 minutes, preferably ≥25.0 minutes and ≤60.0 minutes.

8. The method according to any one of claims 1-7, wherein the method comprises the step of passing the waste plastic feed stream (W) and optionally the vacuum gas oil feed (V) through a dechlorination unit (B) before being supplied to the thermal cracking unit (A), so that the atomic chlorine content of the waste plastic feed stream (W) supplied to the thermal cracking unit (A) is <50.0 ppm by weight, preferably <40.0 ppm by weight, preferably <30.0 ppm by weight, preferably <10.0 ppm by weight, preferably <0.5 ppm by weight, preferably 0.0 ppm by weight, preferably determined according to ASTM UOP 779-08.

9. The method according to any one of claims 1 - 8, wherein the method further comprises the step of introducing the hydrocarbon feed stream (H) into a fluid catalytic cracking unit (FCC) which operates under conditions suitable for cracking the hydrocarbon feed stream (H) in the presence of a catalyst to obtain a product stream (FP) comprising one or more cracked hydrocarbon products.

10. The method according to claim 9, wherein the fluid catalytic cracking unit (FCC) operates at a catalyst - to - oil weight ratio of ≥3:1 to ≤10:1 and a temperature of ≥450 °C and ≤750 °C, preferably ≥500 °C and ≤650 °C.

11. The method according to any one of claims 9 - 10, wherein the catalyst is an equilibrium catalyst (E - CAT) comprising at least one of USY zeolite, X - type zeolite, mordenite, faujasite, nanocrystalline zeolite, MCM mesoporous material, SBA - 15, silica - aluminophosphate, gallium phosphate, titanium phosphate, ZSM - 5 zeolite, RE - Y zeolite, RE - USY zeolite, and CREY zeolite.

12. The method according to any one of claims 9 - 11, wherein the one or more cracked hydrocarbon products are selected from ethylene, propylene, C 4 -C 30 hydrocarbons and C 6 -C 30 aromatics, gasoline, LPG, diesel, heavy oil, dry gas, preferably wherein at a catalyst:oil weight ratio of 4.5, the hydrocarbon feed stream (H) is converted to cracked hydrocarbon products with a conversion of >73.0%.

13. A system adapted to produce a hydrocarbon feed stream (H) as defined in claims 1 - 8, the system comprising: (a) a thermal cracking unit (A) configured to receive a waste plastic feed stream (W) and optionally a vacuum gas oil (VGO) feed (V) to produce a product stream (J); (b) optionally a dechlorination unit (B), wherein the dechlorination unit (B) is in fluid communication with the thermal cracking unit (A) and is located upstream of the thermal cracking unit (A), and wherein the dechlorination unit (B) is configured to receive the waste plastic feed stream (W) and optionally the vacuum gas oil (VGO) feed (V); (c) a blending unit (E) configured to blend at least a portion of the product stream (J) obtained from the thermal cracking unit (A) with at least a portion of the additional vacuum gas oil feed (AV) to obtain a hydrocarbon feed stream (H); (d) optionally a separation unit (C), wherein the separation unit (C) is in fluid communication with the thermal cracking unit (A) and the blending unit (E), such that the separation unit (C) is located downstream of the thermal cracking unit (A) and upstream of the blending unit (E).

14. A hydrocarbon feed stream (H) obtainable by the method according to any one of claims 1 - 8, preferably wherein the hydrocarbon feed stream (H) comprises: (a) an atomic chlorine content of <50.0 ppm by weight, preferably <40.0 ppm by weight, preferably <30.0 ppm by weight, preferably <10.0 ppm by weight, preferably <0.5 ppm by weight, preferably 0.0 ppm by weight, preferably determined according to ASTM UOP 779 - 08; and / or (b) a total inorganic material content of ≤1.0 wt%, preferably ≤0.8 wt%, preferably ≤0.5 wt%, preferably 0.0 wt% relative to the total weight of the hydrocarbon feed stream (H); and / or (c) The weight-average molecular weight of the oligomeric product (O1) as determined by gel permeation chromatography is ≥ 1,000 g / mol and ≤ 20,000 g / mol, ≥ 1,000 g / mol and ≤ 15,000 g / mol, preferably ≥ 9,000 g / mol and ≤ 18,000 g / mol, preferably ≥ 12,000 g / mol and ≤ 18,000 g / mol.

15. Use of the hydrocarbon feed stream (H) according to claim 14 as a feed for improving the product conversion in a fluid catalytic cracking process.

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