133 results about "Hydrothermal liquefaction" patented technology

The invention discloses a resource utilization method of Fenton iron mud. According to the method, a citric acid-ascorbic acid composite solution is used for soaking Fenton iron mud, hydrothermal liquefaction is carried out in an inert reduction system, ferric iron is reduced into ferrous iron, and a ferrous iron solution generated after reaction can directly form a Fenton reagent with hydrogen peroxide to be reused for Fenton reaction. By the adoption of the method, iron can be completely recycled, resource utilization of the Fenton iron mud is facilitated, the mass of the treated filter residues is only 1 / 10 of that of the iron mud, and the disposal amount of hazardous waste is effectively reduced.

The invention belongs to the technical field of solid waste treatment, and discloses a kitchen garbage resourceful treatment device and method. The treatment device comprises a kitchen waste staged treatment unit, a deodorization unit, a heat supply unit, a flue gas treatment unit and a PLC (Programmable Logic Controller) automatic control unit. According to the characteristics of high oil content and high organic matter content of the kitchen garbage, swill oil is separated out through a physical method, then the water of the kitchen garbage is used as a catalyst and a reactant, a subcritical hydrothermal liquefaction reaction is conducted, bio-oil, a water-phase product and biochar are produced, the bio-oil can be used for refining biodiesel, and the biochar can be used for refining biodiesel. The water-phase product can be used for producing liquid water fertilizer, the biochar can be used for agriculture and fuel, harmless, recycling and high-value utilization of the kitchen garbage can be realized, the fertilizer is turned into wealth, potential environmental and health risks caused by improper treatment of the kitchen garbage are avoided, resource waste is reduced, and the environmental, economic and social benefits are remarkable.

The invention relates to the technical field of treatment of biological crude oil, in particular to a method for preparing traffic fuel oil from hydrothermal liquefied biological crude oil. The method comprises the following steps: carrying out distillation treatment on hydrothermal liquefied biological crude oil to obtain purified biological oil and distillation residues; carrying out hydrocracking reaction on the purified bio-oil to obtain cracked bio-oil; performing catalytic hydrogenation reaction on the cracked bio-oil to obtain refined bio-oil; and fractionating the refined bio-oil to obtain the traffic fuel oil. By means of the method, conversion from hydrothermal liquefaction of biological crude oil to traffic fuel oil which can be applied to diesel oil, gasoline and aero-engines is achieved. Distillation residues generated in the distillation process are subjected to metal recovery to prepare high-quality biochar for subsequent field returning. The hydrogen used in the hydrogenation process can come from hydrothermal liquefaction wastewater treatment, so that full recycling and energy regeneration of raw materials are realized.

A method can include: in a heat exchanger, cooling a biocrude oil emulsion stream received from a biocrude oil emulsion source, wherein the emulsion can include a biocrude oil phase, an aqueous phase, and solids; in a first mixing vessel, mixing the emulsion with a solvent to dissolve the biocrude oil phase and form a biocrude-solvent solution; in a first separator assembly, separating the biocrude-solvent solution from the aqueous phase and the solids; in a solvent recovery apparatus, recovering solvent from the biocrude-solvent solution; in a second mixing vessel, mixing the solvent with the aqueous phase and the solids received from the first separator assembly to dissolve biocrude oil remaining in the aqueous phase and the solids; and supplying the solvent and biocrude oil to the first mixing vessel as the solvent. In some examples, such a method can more effectively separate biocrude oil from the emulsion than conventional techniques.

The invention provides a method for preparing bio-oil through synergistic hydrothermal liquefaction of municipal sludge and waste plastics, and belongs to the technical field of waste treatment. According to the method, the yield and quality of the bio-oil can be effectively improved, the problems existing in a traditional sludge treatment method are effectively solved, a new way is provided for treatment of municipal sludge and waste plastic, reduction and energy regeneration of waste are achieved through resource utilization, and the method is suitable for industrial production. The method has remarkable environmental and social benefits, is suitable for large-scale industrial application, and has good market application prospects and popularization value.

The invention provides an energy storage material prepared from seaweed hydrothermal liquefaction byproducts, a method and an electrode, and the method comprises the following steps: treating seaweed into seaweed powder, carrying out hydrothermal liquefaction, and collecting a liquid-phase product and solid-phase residues to obtain a solid-liquid mixture; primarily separating a solid-liquid mixture by using a centrifugal machine, secondarily separating a liquid-phase product by using a filtering device, collecting an oil-phase product, and drying solid-phase residues for later use; and sufficiently and uniformly mixing the oil phase and the solid phase residues, drying, pyrolyzing, synthesizing a carbon material, sequentially pickling and washing the collected product, and drying to obtain the energy storage material charcoal. According to the method, SiO2 in the solid-phase residue ash is used as a self-source template agent, a metal compound is used as a self-source activating agent, the template-like and activating effects of a seaweed hydrothermal liquefied solid phase are utilized, an electrode material with considerable electrochemical performance is prepared under the condition that no chemical reagent with environmental destructiveness is added, the manufacturing cost of a supercapacitor is reduced, and the method is suitable for large-scale popularization and application. The preparation process is simple, and the technological process is green and energy-saving.

The invention provides a method for preparing biological crude oil by promoting hydrothermal liquefaction of pig manure through steel rolling oil sludge, and belongs to the technical field of biomass energy. According to the method for preparing the biological crude oil by promoting the hydrothermal liquefaction of the pig manure through the steel rolling oil sludge, the steel rolling oil sludge serves as a catalyst for the hydrothermal liquefaction reaction of the pig manure, under the subcritical condition, the emulsified structure of the steel rolling oil sludge is destroyed, and fatty acid, water and scrap iron are obtained, the iron scrap can be used as a homogeneous catalyst for hydrothermal liquefaction of organic matters in pig manure, and Fe and Fe3O4 in the iron scrap can be used as a heterogeneous catalyst; in addition, under the subcritical condition, fatty acid can be subjected to thermal cracking to generate H2, iron can also react with subcritical water to generate H2, and H2 can promote hydrodeoxygenation of organic matter and is beneficial to improving the oil quality of biological crude oil; meanwhile, unutilized fatty acid can also be used as a raw material to be converted into biological crude oil, so that the oil yield is further improved.

The embodiment of the application discloses a nitrogen content prediction method, a program product, an equipment and a storage medium, comprising: obtaining experimental data of each biomass raw material under each hydrothermal liquefaction reaction condition, and constructing a data set according to the experimental data; performing cluster analysis on the data set based on the element composition of the raw material and the organic composition of the raw material to obtain each sub-data set corresponding to the data set; performing data enhancement on each sub-data set according to a predetermined random disturbance to obtain each enhanced sub-data set, and determining a model training data set according to each enhanced sub-data set; training a predetermined initial nitrogen migration and conversion prediction model based on the model training data set to obtain a target nitrogen migration and conversion prediction model. The application constructs a nitrogen migration and conversion prediction model suitable for small sample and high heterogeneity data conditions. The prediction accuracy and generalization ability of the target nitrogen migration and conversion prediction model are improved.

The invention relates to a paper-plastic-aluminum packaging waste resource utilization system and method.The system comprises a water supply unit, a material pretreatment unit, a reactor, an electromagnetic induction heater and a three-phase separator, the water supply unit is connected with the reactor, and the material pretreatment unit is connected with a feeding port of the reactor; a condensing coil is arranged in the reactor and is communicated with a water supply unit to form a cooling water supply loop; the electromagnetic induction heater is arranged at the middle lower part of the reactor; and a feed port of the three-phase separator is connected with a discharge port of the reactor. According to the system, the paper-plastic-aluminum packaging waste is treated by utilizing a hydrothermal liquefaction method, so that in-situ online synthesis of high-quality bio-oil is realized, and hydrated alumina with high additional value is recycled; the resource utilization efficiency is obviously improved while the energy consumption and the pollution emission are reduced. The method is green and environment-friendly, the use of an organic solvent or a high-acidity separating agent in a traditional recovery method is avoided, and secondary pollution is reduced; the by-product hydrogen can be used as clean energy, and carbon emission is reduced.

The invention discloses a high-temperature-resistant stirring magneton for biomass hydrothermal liquefaction as well as a preparation method and application of the high-temperature-resistant stirring magneton, and belongs to the technical field of high-temperature-resistant stirring magnetons. The magneton is composed of a magnet and a sheath. The sheath comprises a main body and a plug; the magnet is arranged in an inner cavity of the main body, and the plug is used for sealing the magnet and the main body; the magnet is one of a samarium cobalt magnet and an aluminum nickel cobalt magnet, and the material of the sheath is one of 0Cr17Ni12Mo2 (316), 0Cr17Ni14Mo2 (316L), a C-276 Hastelloy (UNS N10276), a B-3 Hastelloy (UNS N10675) and a titanium alloy TA2. The magneton has the beneficial effects that the magneton applied to biomass hydrothermal liquefaction (in a high-temperature and high-pressure environment with acid and alkali) is provided, the magneton is provided with limited materials and shape ranges of the magnet and the metal outer sheath, and the magneton can be used in a high-temperature acid and alkali-containing aqueous solution environment at the temperature of 500 DEG C; the application prospect and the economic value are relatively high.

The invention discloses a method for preparing an environment-friendly organic water-soluble fertilizer through thermal liquefaction of organic solid wastewater, and belongs to the technical field of solid waste treatment.The method comprises the steps that 1, organic solid waste is crushed and then smashed till the particle size is 0.3 cm or below, and a pretreated material is obtained; (2) carrying out ball milling on the pretreated material, stirring for 10-30 minutes, introducing into a first-stage reaction tank, and reacting to obtain first-stage raw material slurry; (3) removing oil from the primary raw material slurry, introducing the primary raw material slurry into a secondary reaction tank, and reacting for 0.5-2 hours to obtain secondary raw material slurry; and (4) adding a catalyst into the secondary raw material slurry, further reacting for 0.1-2.0 hours to obtain a reaction solution, and tempering and modifying a liquid phase separated from the reaction solution in the step (5) to obtain the organic water-soluble fertilizer. According to the scheme, the process is suitable for most organic solid wastes, the requirement for equipment is low, the hydrothermal liquefaction reaction efficiency is high, and meanwhile, the product quality can be well guaranteed by controlling grease and heavy metal and tempering and modifying the separation liquid.

The present disclosure relates to a continuous biomass hydrothermal liquefaction reaction intelligent control method and system, comprising: real-time monitoring of biomass feed solid content and feed flow rate by mass flow meter, dynamic adjustment of feed flow rate by feed pump frequency converter combined with pre-input material characteristic parameters, control of reaction residence time; based on real-time sampling data and feed flow rate, dynamic adjustment of reaction temperature and reaction pressure by prediction model, and adjustment of discharge valve opening to optimize reaction residence time; real-time monitoring of flow rate, regulating valve opening, separation temperature, separation pressure and liquid level of gas-liquid separation buffer tank and solid-liquid separation buffer tank, automatic adjustment of regulating valve opening according to separation pressure of gas-liquid separation buffer tank and solid-liquid separation buffer tank, and staged recovery of heat by three-stage cooler; judging whether the current key parameters exceed the warning value, if yes, triggering an emergency alarm signal and emergency process. The present disclosure improves the intelligence and safety of the continuous biomass hydrothermal liquefaction reaction process.

Systems and methods of producing biocrude oil include a well having a depth, a top positioned at surface, a bottom portion positioned at a subterranean location, the well comprising casing and tubing positioned therein, forming an annulus. The casing and tubing define a hydrothermal liquefaction (HTL) reaction zone in a bottom portion of the well and a heat transfer and separation zone above the HTL reaction zone. The well includes a cable having an electric heating element positioned in the tubing in the HTL reaction zone configured to transfer energy to biomass slurry flowing through the tubing, converting some of the biomass slurry into biocrude oil by HTL. The well depth and the electrical heating element are sized to produce temperature and pressure in the HTL reaction zone sufficient to form sub-critical water and produce a product fluid comprising the biocrude oil.

The invention relates to a system for realizing oil production by hydrothermal liquefaction of oil-containing waste and supercritical water oxidation innocent treatment step by step and a start control method thereof, and the start control method specifically comprises the following steps: conveying a material to a primary heater through a material pump to heat, after reaching 350 DEG C, entering a secondary heater to maintain the temperature, then entering a reactor to perform hydrothermal liquefaction, and recovering an oil product; the liquefied waste liquid is subjected to supercritical water oxidation treatment, the oxidized waste liquid generates carbon dioxide and water, and the carbon dioxide and the water enter a cooler through an oxidation valve and then are discharged. In order to realize quick start, the invention provides two start modes: one mode is heating by injecting steam into the reactor, and the other mode is starting to heat materials through back pressure, and quick heating is realized by combining external heat tracing and cooling water. In addition, under the supercritical water oxidation working condition, stable operation of the reactor is ensured through accurate temperature and pressure control. According to the method, the starting time is effectively shortened, the treatment efficiency is improved, and good environmental protection and economic benefits are achieved.

The present application relates to the technical fields of hydrothermal liquefaction, and discloses an electrode reaction kettle, which comprises a reaction kettle cavity, a drain port arranged at the bottom of the reaction kettle cavity, a cavity cover arranged at the top of the reaction kettle cavity, and a feed inlet, a liquid inlet, an air inlet and an exhaust port arranged on the cavity cover; and a plasma device fixed to the reaction kettle cavity and / or the cavity cover, which is used to discharge electricity into the reaction kettle cavity to generate plasma. The present application does not involve the use of catalysts, is green and environmentally friendly, and is used for plastic degradation without involving the use of a large amount of catalysts, thus avoiding the phenomenon of subsequent separation and purification difficulties. The electrode reaction kettle can realize the plasma electrolytic degradation of plastics, and the operation process is simple and suitable for industrial production.

The invention relates to a process for treating biomass oil comprising: (a) a step of supplying biomass oil selected from biomass pyrolysis oil, biomass hydrothermal liquefaction oil, lignin oil, and mixtures thereof; (b) a step of oxidizing the biomass oil supplied in step (a) in the presence of an oxidizing agent at a temperature of 90 °C or lower, this step producing an effluent containing at least partially oxidized biomass oil and water; (c) a step of distilling the effluent from step (b) under reduced pressure, separating a distillate containing water from a residue under vacuum to form a stabilized biomass oil with a reduced water content. Figure 1

The invention relates to the technical field of biomass energy conversion, in particular to a continuous biomass hydrothermal liquefaction reaction pressure stabilization control method and system. The method comprises the following steps: judging based on an actual pressure value in the reaction component and a target threshold value, and executing a corresponding control strategy to ensure that the reaction is carried out in a stable pressure environment. Check valves are arranged in the gas inlet link and the feeding link, dampers are arranged in the feeding link and the discharging link, a back pressure valve is arranged at the discharging end, and meanwhile a timer and an opening feedback adjusting device are arranged for a discharging valve, so that stable pressure control in the continuous biomass hydrothermal liquefaction reaction process is achieved. The pressure fluctuation in the reaction process can be effectively coped with, it is guaranteed that the reaction is conducted in a stable pressure environment, the biomass conversion efficiency and the product quality are improved, and the device has the advantages of being simple in structure, accurate in control, high in automation degree and the like.

This invention discloses a method for preparing a composite flotation reagent using biomass hydrothermal liquefaction products, comprising the following steps: Raw material preparation: providing biomass raw materials rich in lipids or proteins; Catalytic hydrothermal liquefaction: placing the biomass raw materials and a composite catalyst in a reactor, reacting at a temperature of 250-350℃ and a pressure of 4-20 MPa, wherein the water content of the biomass raw materials is 70-95%, and the composite catalyst contains alkaline components, metal oxide components, and rare earth element components; Product separation: separating the reaction products into oil and water to obtain bio-crude oil containing amphiphilic molecules; Flotation application: applying the bio-crude oil as a composite flotation reagent to mineral flotation, where the bio-crude oil simultaneously functions as a frother and a collector. This invention uses waste biomass as raw material to prepare a composite flotation reagent with both frother and collector functions, realizing the resource utilization of waste and the green upgrading of flotation reagents, and has the characteristics of wide raw material sources, excellent reagent performance, and environmental friendliness.

The invention discloses a net zero-carbon solar-driven high-quality bio-fuel oil production system, and relates to the technical field of biomass energy conversion. The system comprises: a hydrothermal liquefaction reactor for a hydrothermal liquefaction reaction of biomass; the photovoltaic electric heating device is used for heating the reactor; the solar molten salt device is used for heat preservation of the reactor; the waste heat recovery device is connected with an outlet of the reactor to recover waste heat; the separation device is connected with an outlet of the waste heat recovery device and used for separating biological crude oil and organic wastewater; the biological hydrogen production device is used for producing hydrogen by utilizing wastewater photosynthesis; the hydrogenation upgrading device is used for producing biological fuel oil by using biological crude oil and hydrogen; and the controller is in communication connection with each device. Through solar heat supply and photosynthetic biological hydrogen production, dual dependence on fossil energy is avoided, and net zero carbon emission of a high-quality biofuel production whole chain is achieved.

A waste stream of organic matter such as sewage, plant and plastic matter is received for recycling and treated with high temperature and pressure to generate useful organic products such as bio-oil and gas. Byproducts such as char and an aqueous phase including water can be selectively recycled or beingly discarded. An oxidant added to a reactor containing waste from the waste stream facilitates an autothermal reaction under the temperature and pressure applied to the reactor, boosting the temperature slightly from the reactions therein. The reactor generates useful hydrocarbons such as bio-oil resulting from disruption of organic bonds. A combination of oxidation and radical initiation results from the oxidant and / or radical initiators, and provides an increased yield of bio-oil and substantially pure aqueous phase. A stoichiometric quantity of the oxidant limits complete conversion of carbon into carbon dioxide by limiting available oxygen and therefore favoring hydrocarbon formation.

The present invention relates to a solvothermal process for producing high quality fuels and chemicals from a biomass feedstock using lignin containing bioliquor as a solvent for hydrothermal liquefaction. The lignin containing bioliquor of the present invention is obtained as a waste stream from 2G-ethanol manufacturing plants.

Aqueous wastewater from hydrothermal liquefaction (HTL) systems is typically high in chemical oxygen demand (COD), which renders classic aerobic wastewater treatment to be prohibitively expensive. HTL wastewater can be processed using thermochemical wet oxidation in a manner that is not only cost efficient but also contributes more heat than is required for the energetically demanding HTL process. Provided are methods and devices for integrated hydrothermal liquefaction of biomass and treatment of resulting wastewater.

The present invention provides an improved hydrothermal liquefaction process for managing and sequestering PFAS contaminants in waste materials.

The present invention belongs to the technical field of municipal sludge disposal, and discloses a reliability improvement system for preparing liquid fuel by coupling sludge liquefaction and upgrading, comprising a hydrothermal liquefaction reaction and separation unit, a hydrogenation upgrading and re-separation unit, and a flushing unit. The hydrothermal liquefaction reaction and separation unit is used to perform hydrothermal liquefaction reaction on sludge and obtain a bio-crude oil dichloromethane mixed oil phase; the hydrogenation upgrading and re-separation unit is used to separate dichloromethane from the bio-crude oil dichloromethane mixed oil phase and catalytically hydrogenate the bio-crude to prepare liquid fuel; the flushing unit is used to flush the hydrothermal liquefaction reaction unit and the separation unit and the hydrogenation upgrading and re-separation unit. The present invention ensures that the municipal sludge hydrothermal liquefaction coupled hydrogenation upgrading continuous preparation of liquid fuel system has stability and continuous reliability.

The invention discloses continuous hydrothermal liquefaction treatment integrated equipment and method for organic solid waste, the continuous hydrothermal liquefaction treatment integrated equipment comprises an equipment main body, the equipment main body comprises a preheating section, a reaction section and a heat regeneration section, the reaction section is communicated with the heat regeneration section, and the preheating section is communicated with the heat regeneration section through a heat exchange device; a first stirring device is arranged at the bottom of the heat regeneration section and connected with a slag discharging device and a feeding pipeline. A stirring motor is arranged at the top of the reaction section, and is connected with a stirring shaft extending to a deslagging device in the reaction section; the reaction section is provided with a second stirring device, a heating device is arranged on the periphery of the pipe wall of the reaction section, and the first stirring device and the second stirring device are both fixed to the stirring shaft. The preheating section, the reaction section and the heat regeneration section are integrated, the material transfer waiting time of traditional intermittent treatment is avoided, the treatment efficiency of the organic solid waste is improved, waste heat of the reacted material can be recycled to the preheating section to preheat the to-be-treated material, and the energy consumption of a heating device of the reaction section is reduced.

The invention discloses a regulation and control method and system for biomass hydrothermal liquefaction of a nitrogen-containing heterocyclic ring compound, the regulation and control method for the content of the nitrogen-containing heterocyclic ring of the biomass comprises the steps that a first data set and a second data set are obtained, the first data set comprises element composition, hydrothermal liquefaction conditions and the content of the nitrogen-containing heterocyclic ring of the detected first biomass, and the second data set comprises element composition, hydrothermal liquefaction conditions and the content of the nitrogen-containing heterocyclic ring of the detected second biomass; the second data set comprises the element composition of the second biomass to be regulated and controlled; based on the first data set and a pre-constructed initial machine learning model, obtaining a trained machine learning model, the highest nitrogen-containing heterocyclic ring content output by the trained machine learning model, a characteristic value corresponding to the highest nitrogen-containing heterocyclic ring content and a characteristic weight value corresponding to the highest nitrogen-containing heterocyclic ring content; and the second biomass is regulated and controlled based on the second data set, the characteristic value corresponding to the highest nitrogen-containing heterocyclic ring content and the characteristic weight value corresponding to the highest nitrogen-containing heterocyclic ring content, the nitrogen-containing heterocyclic ring content of the regulated and controlled second biomass is obtained, and the prediction accuracy and the regulation and control effect of the nitrogen-containing heterocyclic ring content are improved.

The invention relates to a highly integrated hydrothermal liquefaction and supercritical water oxidation system for oily wastes. The system comprises a material tank, a reactor, a cooler, a softened water tank and a hydrogen peroxide tank, a discharge port of the material tank is connected with an inlet of the reactor through the material pump and the heater in sequence, an outlet of the reactor is connected with an inlet of the cooler, and an outlet of the cooler is connected with an inlet of the three-phase separator; the softened water tank is connected with a cooling water pump, the cooling water pump is respectively communicated with cavities in the inner walls of the reactor and the cooler, and the hydrogen peroxide tank is connected with an inlet of the reactor through a hydrogen peroxide pump. The invention aims to realize efficient treatment of oil-containing wastes by combining a hydrothermal liquefaction technology and a supercritical water oxidation technology, and solves the problems of low integration level, large occupied area, complex operation and high energy consumption of the existing hydrothermal liquefaction and supercritical water oxidation equipment.

This invention belongs to the field of hydrothermal liquefaction technology and discloses a method for CO2-promoted hydrothermal liquefaction demulsification and separation of rolling mill sludge. The method involves weighing rolling mill sludge into a high-pressure reactor, adding water, and introducing sufficient carbon dioxide gas to purge air from the reactor. A hydrothermal liquefaction reaction is then carried out, and the liquid phase product in the high-pressure reactor is collected and washed with acetone. The washing liquid and the liquid phase product in the high-pressure reactor are then vacuum filtered together. After washing the filter residue with acetone, a filtrate and a filter residue are obtained. The filter residue is dried to obtain the solid phase product of the reaction. Dichloromethane is added to the filtrate, and after thorough stirring and extraction, the liquid is separated. The upper layer is an aqueous solution, and the lower layer is a mixed solution of acetone, dichloromethane, and bio-oil. Rotary evaporation is used to remove the organic solvent from the oil phase mixture, yielding the oil phase. This invention improves the oil phase separation efficiency and calorific value of rolling mill sludge by using CO2 as a reaction atmosphere during the hydrothermal liquefaction process.

The invention provides a method for modifying thickened oil by utilizing a biomass hydrothermal liquefaction water-phase byproduct, and relates to the technical field of petroleum processing. The method provided by the invention comprises the following steps: mixing the biomass hydrothermal liquefaction water-phase byproduct and the thickened oil to form a reaction system, and carrying out hydrothermal cracking reaction to obtain the modified oil, the mass ratio of the biomass hydrothermal liquefaction water-phase byproduct to the thickened oil is (3-8): 10, the hydrothermal cracking reaction temperature is 200-320 DEG C, and the hydrothermal cracking reaction time is 6-30 hours. The hydrothermal liquefaction water-phase byproduct is used as a conversion water source for the hydrothermal cracking reaction of the thickened oil, active hydrogen upgrading is provided for the modification of the thickened oil, the viscosity reduction and modification of the thickened oil are realized, meanwhile, the treatment cost of wastewater generated when the target product bio-oil is prepared through the hydrothermal liquefaction reaction of the biomass is reduced, and the economic benefit is improved.

Provided is a method for producing an oil comprising feeding an olefin-based resin into a reactor, converting the olefin-based resin into an oil by thermal degradation reaction, and recovering the produced oil, wherein the olefin-based resin is a low molecular weight (LMW) olefin-based resin. The LMW olefin-based resin comprises a molecular weight of less than 50,000 g / mol, preferably less than 40,000 g / mol measured according to ISO 16014-4. In an embodiment, method comprises a further step of cracking a higher molecular weight (HMW) olefin-based resin to produce the LMW olefin-based resin. Also provided are an oil produced according to the method and a use of the oil for as a feedstock for production of olefin-based resins. In the examples, a Hydrothermal liquefaction (HTL) process, which uses super-critical water as reaction media, is used for the thermal degradation reaction.