Patent Description:
Thermochemical processes in the absence of oxygen generate solid and gaseous fractions, being able to generate liquid fractions depending on reaction conditions. Processes with long reaction times generate carbons and gases, not liquids. High temperature thermochemical processes, normally higher than <NUM>, generate carbons and non-condensable gases, not liquids, since they carry out a strong cracking that does not produce liquid compounds.

Fast pyrolysis thermochemical technologies generate three product lines: a carbonaceous solid product, a liquid product and a gaseous product called synthesis gas or pyrolysis gas.

Liquid and solid products are the products that have the greatest potential for the development of a circular economy and the integration of pyrolysis products into production processes. Pyrolysis gases or synthesis gases also have significant potential for use as a source of chemical products. The thermochemical transformation of waste and solid products into liquid products, synthesis gas and carbonaceous solids enables the development of a promising route embedded within the processes of advanced biorefineries. Thermochemical technologies with high liquid throughput present a huge technological breakthrough as the treatment of liquids on an industrial scale is more immediate than the treatment of gaseous fractions.

These same arguments can be used for carbonaceous products. Carbonaceous materials have a broad field of application, although they require specific characteristics of quality and stability. The characteristics of stability and quality depend on the polymeric material used as raw material and fundamentally on the thermochemical process and its variables. This field requires technologies that develop different thermochemical stages in a controlled manner, which can be continuously developed to improve the efficiency of the processes.

The most complex non-oxidative thermochemical processes, which are performed in the absence of oxygen, are those which propose the efficient obtaining of liquid compounds. At present, there are many processes for obtaining liquids derived from rubbers, such as tires, which are performed in rotary kiln type clinker or rotary cylindrical reactors in which slow pyrolysis occurs with a very coarse and inefficient heat transfer. There are other processes for pyrolysis of plastics that require single-material plastics with a high degree of cleanliness. These processes require a first heating of the plastics to liquefy them and introduce them into catalytic or thermal reactors. These processes are very expensive, have a high carbon footprint and high energy consumption.

In the field of synthetic polymers from plastics, there are no efficient technologies that allow the processing of multi-material or multi-polymer waste with a high degree of soiling. Treatments that process soiled or mixed waste are required in the field of waste. Most of the time, waste is in the form of multi-material mixtures that cannot be separated into mono-materials efficiently; therefore, technologies are needed to process this type of mixed materials made up of synthetic polymers, natural polymers with other inert materials such as metals and organic and inorganic compounds.

In the field of natural polymers such as lignocellulosic biomass, there are inefficient technologies that are mainly intended to obtain carbon. These technologies are known as carbonisation technologies. There are also some technologies in which, at the same time that carbon is obtained, a liquid mixture made up of organic fractions with a high acid component is obtained. This acidity comes from carboxylic acids that are fundamentally generated in the decomposition of cellulose and hemicellulose. The acidity and the very different composition of organic compounds make their integration in thermal or chemical processes very difficult. This field requires an invention that enables efficient and stable separation of aqueous and organic fractions.

At present, there are pyrolysis processes intended for the treatment of plastic materials only and other pyrolysis processes intended for the treatment of biomass. In the field of waste, there is a large amount of waste that is made up of mixtures of synthetic or plastic polymeric waste and natural polymeric waste such as lignocellulosic biomass. Suitable transformation processes are needed for synthetic materials, natural materials and mainly their mixtures.

When pyrolysis processes plastic waste and mixtures thereof with natural polymers or their derivatives, they produce carbonaceous materials and a liquid stream made up of a mixture of water and organic substances consisting of aliphatic and aromatic hydrocarbons. These liquid streams entrain a part of the heteroatoms present in the polymers, in their fillers or mineral salts; therefore, the hydrocarbons obtained exhibit, together with a great diversity of organic compounds, a presence of heteroatoms such as N, S, Cl, Si, P, Ca, K, Fe, Zn, etc..

Depending on the composition of the processed raw materials, the type of pretreatment, configuration and design of reactors, pyrolysis reaction conditions, presence of catalysts or not, three fundamental fractions are obtained: a solid fraction made up of carbonaceous materials and inorganic elements, a non-condensable gas fraction and a liquid fraction from the condensable gases.

At present, pyrolysis liquids are characterised by being heterogeneous mixtures with a significant presence of particles of various sizes, comprised between <NUM> and <NUM> microns, heavy compounds consisting of hydrocarbons with molecular chains of more than C20, and diolefin compounds, which are unstable over time due to their reactivity. These mixtures are usually settled and distilled to remove heavy components and suspended particles. These operations generate unstable liquids of poor quality, which evolve after a few hours, generating phases and compounds that make their subsequent use difficult. The heterogeneity of the composition means that, with distillation or fractionation operations, undesirable components are distributed irregularly among the different fractions obtained. This lack of quality and homogeneity greatly hinders the industrial utilisation of these mixtures.

Decomposition by means of biomass pyrolysis produces a series of organic compounds with various functional groups, among which are alcohols, ketones, aldehydes and carboxylic acids. These compounds react with each other while undergoing oxidation reactions that modify the composition of the liquids obtained. Organic compounds give an acidic character and are largely responsible for the corrosion shown by liquids generated in thermal depolymerisation processes.

Depending on the type of plastic waste and the type of residual biomass, simple organic or complex aromatic compounds are obtained, derived from the partial decomposition of the lignin present in lignocellulosic waste or plastic polymers.

At present, treatments for the improvement and stabilisation of pyrolysis oils involve the treatment of pyrolysis oils in large and expensive pressure and high temperature facilities to perform hydrodeoxygenation and hydrodesulphurisation in batch or continuous processes. They are also used in high temperature catalytic cracking processes with zeolites or hydrogenation processes with metal catalysts such as Ru, Pd, Co, Mo, Zn, Ni, etc., supported on carbon, aluminas, or silica-alumina. These processes are very expensive in terms of investment and operation and highly sensitive to the contamination present in pyrolysis oils. Another problem with these processes is that they are developed on petrochemical scales, so they are not adaptable or usable at the smaller scales of pyrolysis or depolymerisation plants.

Pyrolysis or co-pyrolysis oils from plastic waste and other waste such as biomass have a complex and variable composition, compared to the hydrocarbon streams that occur in conventional refineries, so they require an innovation in the treatment and in the design of the equipment for their treatment and an improvement in quality and stabilisation.

In the state of the art, there are descriptions of vacuum pyrolysis processes involving mixed plastic and biomass waste at laboratory scale. These processes yield a significant amount of hydrogen-rich pyrolysis oil. One such study is "<NPL>.

There is a need for an innovation that allows improvement and stabilisation on a small scale and that does not require large facilities that are costly in terms of investment and operation.

The present invention describes a non-oxidative thermal depolymerisation process under vacuum conditions comprising a series of devices and methods for transforming polymeric materials into liquid products, functional carbons and synthesis gas.

The technological method is performed in a series of devices by means of which a non-oxidative vacuum thermal depolymerisation is achieved in which there is a hydrogen transfer from waste and synthetic polymeric materials to other products resulting from the non-oxidative vacuum thermal depolymerisation of natural polymers. This method makes it possible to obtain high-quality liquid circular products, bioproducts and functional carbons.

The present invention comprises a series of innovations aimed at transforming a raw material made up of natural or synthetic polymeric materials (herbaceous biomass, lignocellulosic biomass, paper and cardboard, multi-materials, plastic waste, textile materials, etc.) into carbonaceous solid products, aqueous mixtures and hydrocarbon mixtures that meet the specifications required in the chemical industry and/or in the industry for the manufacture of fuels and other technical materials.

The method consists of several sequential processes or stages (PS-<NUM> to PS-<NUM>) that are made up of a series of sub-stages (E-<NUM> to E-<NUM>) which achieve the non-oxidative vacuum thermal depolymerisation with hydrogen transfer, which transforms the polymeric materials (R-<NUM> to R-<NUM>) into simple molecules used as bioproducts or circular products (BP-<NUM> to BP-<NUM>).

The non-oxidative vacuum thermal depolymerisation method for obtaining liquid circular products, bioproducts and functional carbons, wherein a hydrogen transfer takes place to produce hydrocarbons from solid waste, comprises the following stages:.

The process of the invention has the following advantages with respect to the processes of the state of the art:.

To complement the description of the process of the invention and for the purpose of helping to better understand the features of the invention, a set of drawings is attached as an integral part of said description wherein the following has been depicted with an illustrative and non-limiting character:.

The method consists of several sequential processes (PS-<NUM> to PS-<NUM>) that are made up of a series of stages (E-<NUM> to E-<NUM>) which achieve the non-oxidative vacuum thermal depolymerisation with hydrogen transfer, which transforms the polymeric materials (R-<NUM> to R-<NUM>) into simple molecules used as bioproducts or circular products (BP-<NUM> to BP-<NUM>).

Depolymerisation or degradation of a polymer is defined as the separation of bonds between the molecules of the polymer chains, to give rise to monomers, oligomers or base molecules, by intramacromolecular chemical bond separation reactions.

Depolymerisation is a special category of degradation; it is the process that converts the polymer into a monomer, into a mixture of monomers or oligomers or chemical base molecules known as building blocks. Depolymerisation generally occurs with high temperature (thermal) or hydrolytic agents (chemical). Thermal depolymerisation is classified as the chemical reaction in which the polymer chain is converted into monomers or base molecules at a high temperature.

The depolymerisation carried out is applicable to plastics of fossil origin, bioplastics, their mixtures, as well as biodegradable, oxodegradable and anoxodegradable plastics and the mixture of plastics with different proportions of residual biomass. This invention constitutes a circular economy recycling route with a low carbon footprint for waste made up of biomass (natural polymers) and plastics (synthetic waste). This innovative technology enables the chemical recycling of plastic waste in an efficient manner and without generating microplastics.

Circular products are those products which are obtained by means of the treatment of waste that enable the circular use of materials and the circular economy. In the particular case of the invention, circular products refer to liquid products, bioproducts and/or functional carbons obtained from the process of the present invention (BP-<NUM> to BP-<NUM>).

"Functional carbons" are chemically stable carbons that may have been modified in the carbonisation process. These carbons are quality products that can be used in the chemical industry, in the production of fuels and biofuels, in the catalyst industry, energy storage, bioremediation, adsorption of pollutants such as microplastics and metals, and many other uses derived from the organic nature of carbonaceous materials and their modifications.

The liquids produced by means of the non-oxidative thermal process are made up of two fundamental fractions, an organic fraction and an aqueous fraction. Depending on the composition of the processed polymers, as well as the process conditions, two types of organic fractions can be obtained, a light fraction and a heavy organic fraction. These productions are characterised by a light organic fraction supernatant in the aqueous fraction, an aqueous fraction and a heavy organic fraction.

The light organic liquid fraction consists of light, short-chain hydrocarbons with less density than water, consisting of hydrocarbon molecules of compounds having from one carbon atom to more than fifteen. This fraction is made up of oxygenated derivatives and light hydrocarbons.

The aqueous liquid fraction is made up of water with various oxygenated hydrocarbon substances for the most part. Alcohols, aldehydes, ketones, carboxylic acids and short chain sugars derived from the thermochemical decomposition of natural polymers such as cellulose, hemicellulose lignin, etc., are found in this fraction.

The heavy fraction consists of organic molecules with a higher density, made up of molecules having more than fourteen carbons and heavy polysaccharides. In this fraction, polyaromatic compounds derived from cracking or partial cracking of lignin, complex carbohydrates derived from the depolymerisation of complex polysaccharide polymers such as cellulose and hemicellulose, as well as heavy hydrocarbons.

Polymeric materials can be classified as natural polymers such as cellulose, hemicellulose, lignin, leather and chitin, among others, and synthetic polymers, such as plastics and rubbers. These polymers can occur in isolation or mixed with one another. In the case of biomass, it usually consists of mixtures of cellulose, hemicellulose and lignin with other materials such as salts, proteins or fatty materials. In the case of synthetic polymers present in waste, it should be noted that these polymeric materials are usually soiled, degraded and mixed with various natural or synthetic materials.

The waste mixtures consist of variable mixtures of plastics of a diverse nature and composition, with other waste from materials such as paper and cardboard, food waste, wood, plant waste, textile waste, etc..

The devices disclosed in this invention can treat polymeric materials present in waste without the need for segregation, washing stages, separation of components or removal of soiling that accompanies the materials.

These devices can treat natural polymeric materials such as biomass or leather, synthetic polymeric materials such as plastics and rubbers, and it can also treat the different mixtures of such materials.

The solid products obtained (BP-<NUM> and BP-<NUM>) are made up of carbonaceous materials together with inorganic materials present in the processed materials. These carbonaceous materials can be used in various processes and products for the adsorption or stabilisation of products such as concrete, polymers, asphalt mixtures, binders, thermal uses, etc. These carbonaceous materials can be used for carbon sink applications by incorporating them into permanent materials or in agriculture.

The liquid products obtained are a heterogeneous mixture of hydrocarbons that additionally present a series of oxygenated products with variability in the functional groups, in addition to compounds with sulphur, chlorine, nitrogen, phosphorus, silicon and some metals. These liquids must be treated and purified so that they have controlled quality, stability and can be used in chemical and petrochemical industry processes to allow chemical recycling.

Due to the variable composition of the biomass and waste used as the raw material, the organic products present in the depolymerisation liquids consist of mixtures of many linear and branched aromatic and aliphatic hydrocarbon compounds, among which there are alkanes and alkenes in various proportions, many of them with dienes and double bonds. These products with double bonds easily undergo chemical reactions, generating more complex products having a higher molecular weight, even producing oligomers and polymers, often times generating gums and solids. This variability of chemical products causes the products obtained to be unstable and their composition to evolve over time through oxidation reactions and reactions between them.

The stages of the process of the invention (PS-<NUM> to PS-<NUM>) and the sub-stages present in each stage (E-<NUM> to E-<NUM>) are described in detail below.

This process consists of the following stages:.

Process consisting of the stage for the selection and conditioning (E-<NUM>) of the residual biomass (R-<NUM>), polymeric multimaterial waste (R-<NUM>) or their mixtures (R-<NUM>) and a mixing and homogenisation stage (E-<NUM>). These two stages vary slightly depending on the matter to be processed. In the homogenisation stage, a representative mixture of the polymeric materials to be processed can be made so that the different additives are more efficient.

In the case of using synthetic polymeric waste or the mixtures making up same as the raw material to be processed, attention must be paid to the chlorine content from polymers with PVC or PVDC, among others. The materials to be processed must be purified from chlorinated components with a content of less than <NUM>%. This separation must be performed in the raw material selection process. For contents above <NUM>% chlorine or with other halogen contents, the materials must be added as additives in the additivation stage in low temperature reactors (E-<NUM>). Additionally, they can also be added as additives in the additivation stage in high temperature reactors (E-<NUM>).

The raw materials are made up of natural polymeric materials, synthetic polymeric materials and their mixtures. This raw material can be biomass from a crop, waste biomass, municipal waste, biowaste, compost, biostabilised waste, non-hazardous industrial waste, sewage sludge, textile materials, leather, etc. All these residual materials exhibit significant variability in their composition and are generally heterogeneous mixtures of materials in which there is biomass in the form of paper and cardboard, textile materials, wood waste, etc..

In the case of biomass from a crop, the composition is more homogeneous and depends on the type of crop, whether it is woody or herbaceous, and the harvesting and storage system. This type of raw material requires processing to remove unwanted material, shredding and adjusting the particle size and humidity.

In the case of residual biomass, the composition depends on the residual flow from which it comes and the processing and storage conditions.

In the case of residual biomass consisting of mixtures of natural polymeric materials such as lignin, cellulose or hemicellulose, a pre-shredding must be performed, drying if necessary, shredding and homogenisation if the raw material is not homogeneous. In the selection stage (E-<NUM>), the previous treatment that is performed on biomass or waste with a natural polymeric content consists of:.

In the case of waste containing synthetic polymers such as plastics and rubbers, the composition depends on the residual stream of origin, as well as the operations for the storage, collection, separation and processing of each fraction.

The specific waste from specific treatments exhibit a greater homogeneity in relation to their composition. Materials from biostabilisation, bio-drying, sewage sludge, compost, compost refinement, soiled plastics and mixed plastics can be classified in this group of specific waste.

In the case of waste in which there is a representative amount of synthetic polymers, the selection and pretreatment process (PS-<NUM>) involves two stages. The selection stage (E-<NUM>) can entail a series of unitary operations in which the waste is subjected to selective separations and grinding in order to obtain a mixture of polymeric materials that is as homogeneous as possible. The complete sequence of unitary operations that must be performed in this process are:.

The homogenisation stage (E-<NUM>) is necessary to make a homogeneous mixture of the flows of materials to be subjected to non-oxidative vacuum thermal degradation.

This sequence can be carried out completely or partially in the case of the materials used as raw material not exhibiting suitable quality for the subsequent stages described in this invention.

In this process, the following stages take place:.

The non-oxidative vacuum thermal process (NOXVABT) at low temperature (PS-<NUM>) made up of a NOXVABT additivation stage (E-<NUM>) followed by a low temperature non-oxidative thermal stage (E-<NUM>). This stage can be performed in one or more reactors placed in series depending on the humidity content and the additivation required by the materials to be processed.

Previously, together with the feeding of the reactor, there is a low temperature process NOXVABT additive dosing stage (E-<NUM>). These additives are used for the dehalogenation of waste and materials used as raw materials. The additives are dosed by means of an auxiliary hopper with a dosing device if they are additives in solid state or in the form of nozzles if they are additives in liquid state or in a solution.

The additives that can be used to reduce halogen compounds in organic liquids are selected from the following list: alkali and alkaline earth salts, metal oxides, organic and inorganic acids, zeolites, bentonites, sepiolites, attapulgites and natural or modified aluminosilicates, kaolinites and montmorillonites or mixtures thereof.

Additivation proportions are established based on the halogen content present in the materials to be processed, and it can range between <NUM>% and <NUM>% by weight of the materials to be processed.

This additivation stage has the dual objective of obtaining a high-quality liquid fraction after all the processes listed in the invention and obtaining a raw carbon which, after the carbonisation process and combined with the high temperature vacuum carbonisation process additivation stage (E-<NUM>) has a high quality and functionality.

The Low Temperature Non-Oxidative Vacuum Thermal Stage, NOXVABT (E-<NUM>) requires a thermal energy input from the exhaust gas output from the combustion equipment and thermal oxidation of the gases obtained in the non-oxidative vacuum thermal depolymerisation and carbonisation processes. In case of requiring a greater thermal input, it can be supplemented with auxiliary biomass, biogas, gas or liquid fuel combustion equipment.

This configuration has a dual objective of adjusting the humidity of the materials to be processed to less than <NUM>% and making direct contact of the additives with the materials to be depolymerised.

The fundamental characteristics of this process are:.

The high temperature non-oxidative vacuum thermal depolymerisation process (PS-<NUM>) is configured in two consecutive stages:.

PS-<NUM> process is a sequential process that is performed in at least two screw reactors in series, and it can be made up of up to <NUM> reactors in series depending on the characteristics of the materials to be processed, the performance to be obtained and the desired residence time.

Previously, together with the feeding of the reactor, there is a low temperature process additive dosing stage (E-<NUM>). These additives are used for the dehalogenation of waste and materials used as raw materials.

In addition to the low temperature process additives dosage stage (E-<NUM>) and in order to obtain qualities of liquid products with a low content of chlorine and other halogens, these reactors are equipped with an additive supply system at the outlet of these reactors in the high temperature NOV reactor inlet additivation stage (E-<NUM>).

Solid organic materials can be converted to liquids through intermediate or rapid thermal depolymerisation processes, which processes are characterised by performing thermochemical cracking reactions. In order to obtain higher efficiencies and for there to be no oxidation or combustion reactions, it is necessary for the entire process to take place under non-oxidative conditions. To maximise the efficiency of the depolymerisation processes and to reduce the side reactions of cyclisation, aromatisation and partial polymerisation, it is necessary to minimise the contact of the single molecules resulting from the depolymerisation processes with the polymers in depolymerisation. This stage is carried out under vacuum conditions.

The biomass or polymers that come from PS-<NUM> are deposited in the main feed hopper and later introduced into the reactor inlet distributor by means of a worm screw.

The high temperature non-oxidative vacuum thermal depolymerisation process, NOXVADAT must be carried out in a reactor that allows the co-processing of biomass waste materials and plastic waste at the same time. Both residual materials can be found in variable mixtures in household, commercial, municipal, urban and industrial waste.

Once the polymeric materials are inside the high temperature non-oxidative vacuum thermal depolymerisation reactor (R-NOXVADAT), in the absence of oxygen, with high heat input with a controlled temperature regime and specific residence time, the depolymerisation of the polymers takes place, generating a volatile fraction which is entrained towards the raw gas process collectors (PS-<NUM>). The raw gases are made up of a high temperature stream of syngas, particles, heavy and very heavy compound, which are entrained from the reactors by the syngas extractors.

The sequence of reactors of this invention makes it possible to carry out non-oxidative vacuum thermal depolymerisation reactions under controlled conditions on heterogeneous mixtures of variable composition, such as urban waste and industrial waste. These heterogeneous mixtures between oxygenated and synthetic polymers generate side reactions in which hydrogen exchange and a reduction of oxygenated compounds take place.

One of the improvements made possible by the invention is the simultaneous co-processing of mixtures of synthetic and natural polymers. Under the reaction conditions carried out in the equipment, a depolymerisation with hydrogen transfer is performed in which the synthetic polymers act as hydrogen donors to the depolymerisation products of the natural polymers. Thus, the non-oxidative vacuum depolymerisation or co-depolymerisation co-processing mixtures in the described process achieve circular compounds or liquid and solid bioproducts with a lower content of oxygenated compounds than conventional biomass depolymerisation or pyrolysis liquids and carbons.

Depending on the reaction conditions carried out in the reactor and the balance between oxygenates derived from the biomass and the hydrogen donor compounds from plastic waste consisting of synthetic polymers, different qualities of solid, liquid and gaseous products will be obtained. This non-oxidative vacuum thermal depolymerisation with hydrogen transfer achieves organic fractions that are compatible with the oil and petrochemical industry requires a low content of oxygenated compounds that give the liquids high polarity and high acidity.

In order to obtain modified depolymerisation oils of quality derived from transfer depolymerisation, the presence of residual synthetic polymers present in the reactor is required to be at least <NUM>%. Although it is noted that mixtures with percentages of plastic polymers greater than <NUM>% cause significant changes in the amount of oxygenated compounds and therefore in the quality of the liquids.

In reactions in which synthetic materials account for percentages of less than <NUM>%, they can be considered reducing additives, deoxygenating additives, hydrogenating additives, oxygenate reducing or improving additives.

In the PS-<NUM> process, the following stages take place:.

The high temperature non-oxidative vacuum carbonisation stage allows the addition of additives by means of the carbonisation and functionalisation additivation stage (E-<NUM>). This dosing can be performed by means of an auxiliary hopper with a dosing device if they are additives in solid state, in the form of nozzles if they are additives in a liquid or in a solution, or in the form of gas nozzles if they are gaseous additives, such as water vapour or CO<NUM>.

The additives that can be used for the functionalisation of the carbons are selected from the group of alkali and alkaline earth salts (CaCO<NUM>, CaSO<NUM>, Na<NUM>SO<NUM>, Na<NUM>CO<NUM>, NaHCO<NUM>, K<NUM>CO<NUM>, CaMg(CO<NUM>)<NUM>, etc.), hydroxides (NaOH, KOH, Fe(OH)<NUM>), Fe(OH)<NUM>) FeO(OH), etc.), metal oxides (CaO, ZnO, MgO, P<NUM>O<NUM>, FeO, Fe<NUM>O<NUM>, Fe<NUM>O<NUM>, FeOOH, Fe(OH)<NUM>), etc.), organic and inorganic acids (H<NUM>SO<NUM>, HNOs, H<NUM>PO<NUM>, CH<NUM>-COOH, etc.), gases (CO<NUM>, water vapour, etc.) or mixtures thereof.

The combination of reaction conditions with additives makes it possible to obtain functional carbon products (BP-<NUM>) and raw carbon products (BP-<NUM>) in cases where no type of additivation is performed. Another innovation is the incorporation at the carbonisation inlet of an inlet for gases such as CO<NUM> o water vapour used as additives in functionalisation processes.

Functional Carbon Wetting Stage (E-<NUM>) Stage required to ensure the safety of the process in relation to the intrinsic explosive conditions of carbon. The purpose of this stage is to increase the humidity of the carbon obtained to a content above <NUM>%. Wetting is performed by nozzle type spray devices inserted at the outlet of the final carbonisation reactor (in the case of having several in series). Wetting can be performed with water, deionised water, osmotised water, distilled water or process water, depending on the physicochemical requirements of the functional carbon products and the subsequent additivation stage.

Post-Carbonisation Additivation Stage (E-<NUM>) Stage required to neutralise the products used in the functionalisation of the functional carbons.

Functional Carbon Washing Stage (E-<NUM>) This stage requires washing the functional carbon obtained with distilled or demineralised water until a stable pH is obtained. In the case of the production of functional carbons intended for agricultural applications such as fertilisers, the washing stage may not be performed to ensure a greater presence of mineral nutrients present in the functional carbon produced.

Process PS-<NUM> leads to the separation and recovery of the components present in the raw gases of the non-oxidative vacuum thermal depolymerisation and carbonisation processes for their capture and treatment of usable streams. The purpose of this process is to separate the streams contained in the raw gases for their subsequent processing in each of the following sequential processes.

In this raw gas treatment process, the following stages take place:.

This innovative configuration makes it possible to achieve a high condensable/non-condensable gas separation performance and to maximise the amount of non-oxidative vacuum depolymerisation liquids produced.

Quench stage that allows the control and regulation of the temperature of the quench process. This temperature regulation makes it a versatile multifunctional equipment that can be adapted to the process conditions required for the condensation of heavy liquids.

In the case of the treatment of synthetic polymers or mixtures of synthetic polymers with natural polymers, the working temperature is established between <NUM> and <NUM>. These working temperatures facilitate the condensation of the organic fractions derived from the depolymerisation of synthetic polymers.

In the case of the exclusive treatment of natural polymers such as lignocellulose, the working temperature must be established between <NUM> and <NUM>. These process conditions cause the heavy organic liquids to condense efficiently with the aqueous liquids derived from the depolymerisation of the biomass and its intrinsic humidity.

This stage performs the first separation of heavy hydrocarbons with temperature control of raw gases. Raw gases exit the high temperature non-oxidative vacuum thermal depolymerisation reactor and are quenched in a temperature controlled quench stage. This equipment produces a stream of heavy liquid condensation products. It consists of a quench condensation tower which comes into sudden contact with the liquid fraction produced by the process itself, but at a temperature below its boiling point, which causes the condensation of most of the organic compounds contained therein. The design of this stage is such that it makes it possible in the process for there to be the shortest possible distance between the gas outlet and the quench condensation tower. This innovation makes it possible to avoid cooling the gas before condensation, enabling continuous operation of the process gases.

The fundamental characteristics of the separation devices are the following:.

For the exclusive processing of natural polymers or biomass or biomass mixtures, the raw gases treated by this equipment can be diverted to the syngas burner recovery process (PS-<NUM>).

For the processing of synthetic polymers or their mixtures, the raw gases must be sent to the following stages to perform secondary and successive washings.

Second solid particle separation and secondary raw gas washing stage. The gas resulting from the first quench tower passes through a second quench tower that manages to lower its temperature again and partially condense the organic fractions. This stage of the Venturi scrubber allows an enrichment of organic compounds in the composition of the liquid.

The equipment performs the dual function of enrichment and cleaning of possible impurities in the non-condensable gas fraction. This cleaning of particles enables the subsequent thermal utilisation thereof by means of the combustion stage.

The fundamental characteristics of this solid separation and washing device are the following:.

This design configuration involves a lower investment cost, and it also takes up less space. The Venturi scrubber device equipped with a gas speed control system which allows it to have a wide working ratio. The design of the device allows it to be adjustable, to be able to work in mist, aerosol and high particle load cycles.

The innovative design provides significant advantages in relation to conventional systems in terms of performance and adaptation of working conditions. This design offers high performance separation of fine and ultrafine particles from organic streams from non-oxidative vacuum thermal depolymerisation processes.

Separation stage for separating suspended particles and heavy compounds from the organic stream by means of a cyclone spray scrubber to capture suspended particles and heavy compounds.

The fundamental characteristics of this device for separating solid particles and capturing heavy organic compounds are the following:.

Stage that redirects the heavy organic streams from stages E-<NUM> and E-<NUM> to a stirring and homogenisation tank. This stage regulates the temperature of the homogenised heavy element stream at a temperature comprised between <NUM> and <NUM>. The temperature regulated and homogenised stream is absorbed by a screw pump and by a worm screw that drives it to the recirculation circuit of the device of E-<NUM>.

The innovation of homogenisation and temperature control of organic streams for the recirculation of stages E-<NUM> and E-<NUM> represents a great increase in the performance of processes for obtaining organic liquids from depolymerisation processes.

Very heavy products (bitumen, tar, etc.) coming out from the lower part of the heavy element tank are removed in the very heavy stream capture stage. These products are output by means of a worm screw or a screw pump and is directed to the carbonisation reactors (E-<NUM>).

The process allows the outlet of heavy organic products (BP-<NUM>) for use in external processes. These products are used in refining processes, in the manufacture of waterproofing materials, pavements and asphalt mixes, carbonaceous materials, etc..

Process in which washing and condensation is performed in a low temperature controlled quench type device with variable reflux, followed by a stage of settling and separating process water and light streams.

Process in which the following stages take place:.

The light gas stream is subjected to a condensation process in a quench type condenser adapted for light streams of hydrocarbons mixed with water. This equipment must work at a temperature comprised between <NUM> and <NUM> degrees Celsius measured in the light liquid (E-<NUM>).

The most important specifications of this device are the following:.

In this stage, the light streams are sent to a settling tank to remove the water therein by means of settling. Settling and separation stage. The light liquid goes to a settling tank to remove the water (E-<NUM>).

Process of capturing light streams in which a stage of homogenising the different light streams, followed by multifiltration to obtain a light organic stream product of quality.

Stage that mixes light organic streams with heavy organic streams in a stirring and homogenisation tank. The light organic stream obtained with the heavy organic stream is mixed by means of a stirring tank with a pump (E-<NUM>).

Multifiltration stage of the homogenised organic stream. The device allows a progressive multifiltration of <NUM> microns, and <NUM> and <NUM> microns (E-<NUM>).

Syngas stream capture and treatment process in which two stages take place:.

Heat exchange stage performed in a gas-liquid tubular condenser (E-<NUM>). The gas coming out of the light condensation system passes through a tubular exchanger with a chiller to condense the lightest light elements. The light condensate stream is sent to the light element tank.

The specifications of this device are as follows:.

Vacuum stage (E-<NUM>). The light gas cleaned of condensable elements is sent to an extractor that performs the vacuum of the whole circuit. This extractor, together with the vacuum seals of the reactors, maintains the sequential vacuum conditions in all the elements of the process.

The vacuum extractor is used to drive the syngas streams to the reuse process.

Improvement and selective adsorption process performed in multiple stages in which the following stages take place:.

This process as a whole has the function of eliminating pollutants present in light organic streams, acidity reduction, colour improvement and stabilisation.

This process consists of one or more vertical columns filled with adsorbents specific for each type of pollutant. The adsorbents are shaped in the form of spheres or extruded with a size between <NUM> and <NUM>, in order to reduce the head loss in the bed. The adsorbents to be used are specific for each adsorption stage. It is possible that fillings could be combined to reduce the number of beds.

Stage consisting of adsorption columns, one for chlorine and the other for sulphur. Chlorine adsorption is performed by means of beds filled with compounds such as calcium, sodium or potassium carbonate supported on alumina, silica-alumina, zeolites, activated aluminas; calcium oxide, sodium oxide, zinc oxide and copper oxide supported on alumina, silica-alumina or zeolites; bentonites doped with sodium potassium, calcium or magnesium. Sulphur adsorption is performed by means of beds filled with reduced or oxidised nickel, nickel-molybdenum, nickel-tungsten supported on alumina or silica-alumina, zinc oxide and copper.

Stage consisting of metal (Fe, Zn, Ca, Na) adsorption columns, made up of beds filled with macroporous alumina or silica-alumina, activated carbon; acid resins, zeolites, clays or activated bentonites.

Stage consisting of nitrogenous compound adsorption columns made up of beds filled with acid aluminosilicates, polymeric resins, bentonites, activated carbon, biochar, natural or activated clays.

Stage consisting of columns for the adsorption and removal of water present in the hydrocarbon mixtures making up the liquid stream. This removal is performed through the hydration reaction performed by compounds such as alkali and alkaline earth hydroxides and oxides. It can also be performed by contacting liquids with molecular sieves, zeolites or clays with hydration potential.

Stage of contacting the light hydrocarbon stream with adsorbent products to improve the colour. This adsorption can be performed by means of using activated carbon, natural clays, modified or activated clays and mixtures of these products. To regulate the colour in persistent products, it is possible to implement prior to this stage an additivation stage for adding as an additive a strong acid such as H<NUM>SO<NUM>, HNO<NUM>, H<NUM>PO<NUM>, or the like, followed by neutralisation and separation of the aqueous phase.

Stage consisting of carboxylic acid adsorption columns, where such adsorption is measured by the reduction of TAN. These columns are made up of beds filled with activated aluminas, calcium, sodium, potassium or magnesium compounds supported on alumina, silica-alumina, clays, mixed copper and zinc oxides on alumina or silica-alumina, activated carbon.

The liquid fractions are highly heterogeneous with the presence of reactive compounds such as diolefins, styrene and other conjugated double bonds. These compounds cause the organic oil to have an unstable behaviour during storage, transportation and other logistics operations. This instability generates sediments consisting of gums and polymers. The innovation carried out for light organic streams derived from non-oxidative vacuum depolymerisation processes or co-processing consists of continuous additivation or intermediate tanks of chemical products which improve stability, remove emulsions and increase the useful life of the light fractions. Additivation is performed in an intermediate tank equipped with stirring and dosing of stabilising additives that inhibit degradation processes.

The stabilising additives used are organic compounds from the families of benzoquinones, hydroquinones, multi- hydroxybenzenes, alkyl derivatives of benzenes, halogenated quinones and their derivatives. Some of the compounds used can be: <NUM>,<NUM>-dihydroxybenzene, <NUM>,<NUM>-benzoquinone, <NUM>,<NUM>,<NUM>,<NUM>-tetrachlorobenzoquinone, <NUM>,<NUM>-dihydroxy-<NUM>-t-butylbenzene, <NUM>,<NUM>,<NUM>-trihydroxybenzene, substituted hydroquinones (<NUM>,<NUM>-di-t-butylhydroquinone and <NUM>,<NUM>-di-t-amyl-hydroquinone, and halogenated hydroquinones), alkyl derivatives of phenols (<NUM>,<NUM>-di-t-butyl-<NUM>-methylphenol) t-butylpyrocatechols (<NUM>,<NUM>-dihydroxy-<NUM>-t-butylbenzene), and derivatives of the amine family such as: phenylenediamine, hydroxyamine, etc..

The dosages of the stabilising or inhibitor additives vary depending on the composition of the functional groups that provide instability. As a general rule, a dosage range comprised between <NUM> and <NUM>,<NUM> ppm of the mixture to be inhibited can be established.

Process leading to the adaptation of the syngas stream so that it can be recovered in the burner and its thermal energy can be used in the different processes. In addition, devices to achieve a minimum emission of pollutants in the form of non-harmful gases are added.

Syngas stream capture and treatment process in which the following stages take place:.

Basic scrubber separator basic washing stage with bases in the form of oxides or hydroxides such as NaOH, KOH, CaO, Ca(OH)<NUM>, etc., which allow the capture and neutralisation of the acid compounds derived from the halogenated compounds present in the raw material used in the depolymerisation processes. This stage allows the removal of HCl, HBr, HF, SH<NUM>, etc. The washing water can be regenerated or treated by absorption in activated carbon systems, by means of electrodialysis systems, membranes or ultrafiltration. The passage of the syngas streams through this washing stage in a basic scrubber allows the removal of the halogens present in the syngas in a way that ensures the formation of dioxins and furans in the subsequent combustion stages.

Stage that is performed in an suspended droplet impact separator device consisting of a device with a disordered bed and mesh for droplet separation. It must have a configuration with a diameter comprised between <NUM> and <NUM> for suitable droplet separation and agglomeration. The purpose of this stage is to obtain a syngas referred to as a suspended liquid-free dry syngas.

Process stage consisting of a safety device that prevents the formation of unwanted gas mixtures. The device must be designed to work at low opening pressures (less than <NUM> Pa (<NUM> mbar)) and must involve a minimum head loss. The purpose of this stage is to avoid the return of the syngas and provide safety in the stage prior to the burner.

In processes that use synthetic polymers or their mixtures, the burner stage must be performed in a device with an air vein design. This configuration makes it possible to work with the vacuum combustion chamber between -<NUM> and -<NUM> Pa (-<NUM> and -<NUM> millibar). This burner configuration makes it possible to absorb gas fluctuations related to flow rate and variation in the calorific value derived from its composition.

The specific characteristics of the syngas that can be processed in this device are the following:.

For processes that use biomass or biomass mixtures greater than <NUM>%, the syngas burner must have a multi-stage configuration with recirculation.

The configuration of the stage consists of a combustion gas recirculation and regulation chamber contiguous to the burner with the following specifications:.

The technology developed allows for an advanced control system for combustion gases by means of which the temperature gradient in the depolymerisation reactor jackets is controlled.

Thermal oxidation stage (E-<NUM>) in which the combustion gases are oxidised in a thermal oxidiser. The thermal oxidation stage is intended for the complete oxidation of VOC compounds with high efficiency and low NOx and CO emissions. The complete thermal oxidiser system ensures oxidation and destruction of potential hazardous air pollutants (HAPs) and volatile organic compounds (VOCs) from the resulting gas stream. These pollutants are generally based on carbon compounds and, when destroyed through thermal combustion, are chemically oxidised to form CO<NUM> and H<NUM>O, avoiding unburned products.

The implementation of the thermal oxidiser, with up to <NUM> MWt of unit thermal power, allows the recovery of thermal energy from the syngas, which is intended for carrying out the thermochemical depolymerisation process, minimising the consumption of fossil fuels, as well as the treatment of combustion gases, thus minimising the emission of pollutants into the atmosphere. The exhaust gases from the thermal oxidiser are diverted to a catalytic combustion stage that ensures the complete oxidation of CO and hydrocarbons, and CO<NUM>, H<NUM>O, while at the same time reducing NOx to N<NUM>.

This stage consists of selective catalytic oxidation and catalytic reduction systems through simultaneous cross-reactions by means of which pollutants NOx, CO, CHx and dioxins are transformed into harmless components.

The stage is carried out in a device that significantly reduces the emissions of products generated in high temperature combustion, such as CO, NOx and unburned compounds (CxHy). The specifications of this device are as follows:.

In the second phase, the reaction is 2CO + 2NO → 2CO2 + N2.

The sequence of these devices ensures the minimisation of atmospheric emissions derived from catalytic oxidation using active oxidation catalysts. The catalysts that can be used are: cerium oxides, manganese titanium, chromium, iron or metals such as nickel, palladium or platinum supported on Al<NUM>O<NUM> or Zr<NUM>O<NUM>, among others.

Mixture of plastics (between <NUM>% to <NUM>%) and biomass (between <NUM> and <NUM>%), from waste.

The thermal process (PS-<NUM> low temperature process, PS-<NUM> high temperature non-oxidative vacuum depolymerisation process, PS-<NUM> high temperature carbonisation process), PS-<NUM> raw gas treatment process, PS-<NUM> light gas process and PS-<NUM> syngas capture and process work under vacuum conditions. This configuration enables maximum liquid production efficiency and minimises syngas generation.

Light element quench stage. The gas then goes to another light element quench type condenser at a temperature of <NUM>, which can range between <NUM>-<NUM> of the light liquid, which liquid is made up of hydrocarbons and water (E-<NUM>).

Claim 1:
A non-oxidative vacuum thermal depolymerisation process for obtaining liquid circular products, bioproducts and functional carbons, wherein a hydrogen transfer takes place to produce hydrocarbons from mixtures of natural and synthetic polymeric residues, comprising the following stages:
a) selecting and treating waste by means of drying, grinding and removing metallic elements and chlorinated polymers, and optionally homogenising the residue;
b) adding additives to the mixture resulting from the previous stage;
c) performing non-oxidative vacuum heat treatment of the mixture obtained in the previous stage at working temperatures between <NUM> and <NUM> for synthetic polymers or up to <NUM> for biomass, and pressures between -<NUM> and -<NUM> Pa (-<NUM> and -<NUM> millibars);
d) performing non-oxidative vacuum thermal depolymerisation of the mixture obtained in the previous stage at working temperatures between <NUM> and <NUM> and pressures between -<NUM> and -<NUM> Pa (-<NUM> and -<NUM> millibars), where a carbonaceous solid and raw gases are obtained;
e) adding additives to the carbonaceous solid resulting from the previous stage;
f) performing non-oxidative vacuum carbonisation and functionalisation of the mixture obtained in the previous stage at temperatures higher than <NUM> and pressures between -<NUM> and -<NUM> Pa (-<NUM> and -<NUM> millibars);
g) wetting the carbon obtained in the previous stage to at least <NUM>% humidity, and, optionally performing additivation and washing of the wetted carbon;
h) condensing and separating the raw gases obtained in stage d) into <NUM> fractions: light gaseous organic fraction, heavy liquid organic fraction and very heavy liquid organic fraction;
i) performing complete or partial recirculation of the very heavy organic fraction to the carbonisation reactor of stage f);
j) condensing and cleaning the light gaseous organic fraction obtained in stage h) to obtain an aqueous fraction, a light organic liquid fraction and a syngas fraction;
k) improving and cleaning the light organic liquid fraction obtained in the previous stage by means of adsorption columns, optionally adding stabilising compounds to the liquid fraction resulting from cleaning;
l) performing complete or partial recirculation of the syngas fraction obtained in stage j) to a burner to provide energy to the different stages of the process;
wherein stages b) and c) are performed simultaneously, and wherein stages e) and f) are performed simultaneously.