Start of section
Production, amateur
Radio amateurs
Aircraft model, rocket-model
Useful, entertaining 		Stealth Master
Electronics
Physics
Technologies
Inventions 		Secrets of the cosmos
Secrets of the Earth
Secrets of the Ocean
Tricks
Map of section
Start
Forum
Use of the site materials is allowed subject to the link (for websites - hyperlinks)

Navigation: =>

Home / Patent catalog / Catalog section / Back /

METHODS OF PRODUCING LIQUID AND SOLID FUEL FROM INDUSTRIAL AND DOMESTIC WASTES
INVENTION
Patent of the Russian Federation RU2127296

METHOD FOR PROCESSING PLASTIC WASTE AND PLASTIC WASTE

The name of the inventor: Rolf Holighaus (DE); Klaus Niemann (DE); Martin Rupp (DE)
The name of the patent holder: Weba El Aktiengesellschaft (DE)
Address for correspondence: 101000, Moscow, Maly Zlatoustinskiy per., 10-15, "EVROMARKPAT"
Date of commencement of the patent: 1994.03.25

To obtain chemical raw materials and components of liquid fuel, plastic waste and plastic waste are depolymerized to the pumped and volatile phases. The volatile phase is separated into a gas phase and condensate, which is subjected to standard refinery processes, and the pumped phase is subjected to liquid-phase hydrogenation, gasification, or combination of these technological operations. The depolymerization is carried out without the addition of hydrogen, preferably at a pressure of 0.01-300.0 bar, preferably 0.1-100.0 bar, in particular 0.2-2.0 bar, at 150-470 ° C, preferably 250-450 O C and a reaction time of 0.1-10.0, preferably 0.5-5.0 hours, and three product streams are withdrawn in amounts of 15-85% by weight of depolymerizate, 10-80% by weight of condensate, a and 5 -20 wt. % Of the gas mixture, each in terms of the initial mixture of plastics.

DESCRIPTION OF THE INVENTION

The invention relates to a method for processing plastic waste and plastic waste in order to obtain chemical raw materials and components of liquid fuel.

The invention is based on a process for the hydrogenation of a carbonaceous material in which polymers are added to high boiling oils, in particular polymer wastes in particulate or dissolved form, and this mixture is hydrogenated in the presence of hydrogen to produce fuel and chemical raw materials (compare DD 254207 A1 )

DE-A-2530229 describes a process for the processing of old tires, rubber and / or other plastics in liquid, gaseous or solid products by depolymerization in a solvent at elevated pressure and elevated temperature. In this method, in particular, there should be no emissions of harmful substances into the atmosphere, such as SO 2 soot and the like. For example, old tires after grinding and mixing with the recycle oil of the hydrogenation product were introduced into a hydrogenation reactor with hydrogen addition at a hydrogen pressure of 150 bar and a temperature of 450 ° C. in the presence of digestion and hydrogenation catalysts.

DE-A-2205001 describes a process for the heat treatment of waste and rubber in which the waste is split at a temperature of 250 to 450 ° C in the presence of an auxiliary phase at a reaction temperature in the liquid state.

Further in the article Ronald H. Wolk, Michael C. Chervenak and Carmine A. Battista in "Rubber Age", June 1974, pp. 27-38 , describes the hydrogenation of old tires for the production of liquid products based on hydrocarbons boiling in the gas oil range, But also for the purpose of hydrogenation of carbon black, repeatedly used as a filler.

Further, a method is known in which waste polymers, in particular utilitresin, are dissolved in residual oil refinery products. The resultant mixture is then coked to produce coke. In this case, gaseous and liquid products are formed. The latter, with suitable processing, are suitable as fuel components (compare DD 0144171) .

The concentration of the polymer in the hydrogenation product used is, for example, from 0.01 to 20% by weight, according to the method according to DD 254207. Hydrogenation treatment of heavy oils with polymer solutions and / or suspensions should be limited to hydrogenation processes in which the hydrogenation process is carried out in tubular reactors without or with a suspended catalyst. The use of fixed bed reactors would result in limited use of the polymers, in particular when polymers are added that depolymerize already in the heating step to about 420 ° C. before entering the reactor. A method for processing high molecular weight organic waste is known with the aim of obtaining chemical raw materials and liquid fuel components according to SU 1041557, which can be considered as the closest analogue. The method consists in depolymerizing the starting materials without the addition of hydrogen to the pumped phase and the volatile phase at a temperature of 150 to 430 ° C. with the addition of a hydrocarbon solvent.

The object of the present invention is to not limit the amount of added recycled material to no more than 20% by weight in the process for processing plastic waste. In the methods of conversion of heavy liquid fuels used in refineries.

Further, the problem arises that during the chemical processing of plastic waste, chlorinated plastics must also be processed with them. The hydrogen halides formed in depolymerization in known methods as gaseous cleavage products require special precautions.

Another problem arises from the fact that the plastic waste used and the plastic scrap material contain some, and not least, inorganic impurities, such as pigments, metals and fillers, which can make it difficult to carry out certain depolymerization processes or to process the depolymerization products.

It is therefore an object of the present invention to provide a method that allows the presence of these components. They concentrate in one phase, from which they can then be processed for processing, and allowing the presence of these ingredients, while other phases free from these inorganic impurities should be processed at a lower cost.

The next task is to unload or more efficiently use, from the point of view of the required volumetric productivity, such complex and capital-intensive process steps as low-temperature (semi-coking), gasification or liquid-phase hydrogenation.

In accordance with the invention, the object is achieved by a method for processing plastic waste and plastic wastes in order to obtain chemical raw materials and components of liquid fuel by depolymerizing the starting materials without the addition of hydrogen and obtaining from them a volatile phase and depolymerization in the form of a pumped phase in which the volatile phase is divided into a gas phase Phase and condensate, which is subjected to standard refinery processes, and the pumped phase is subjected to liquid phase hydrogenation, gasification, or combination of these technological operations.

In particular, the depolymerization is carried out at a pressure of 0.01 to 300 bar, preferably 0.1 to 100 bar, at a temperature of 150 to 470 ° C., preferably 250 to 450 ° C., and a reaction time of 0.1 to 10 hours, preferably 0.5 5 hours, three product streams being withdrawn in amounts of: 1) 15 to 85% by weight of depolymerizate, 2) 10.0 to 80.0% by weight of the condensate, and 3) 5.0 to 20.0% % Of the gas mixture, each in terms of the initial mixture of plastics.

Depolymerization is expediently carried out in the presence of a catalyst.

An organic solvent can be added to the initial plastic waste and waste paper.

The condensate is preferably subjected to hydrogenation treatment on a fixed catalyst, on a moving catalyst or a fluidized catalyst bed.

Gaseous products of depolymerization can be fed to liquid phase hydrogenation, with a scrubber, if necessary, connected to remove acidic components such as hydrogen chloride.

The gaseous products of depolymerization (gas), the condensable depolymerization products (condensate) and the liquid phase (depolymerizate) containing the pumped viscous products of depolymerization formed in this process are separated by separate streams, and the condensate, a and depolymerization are separately processed. The technological parameters of the process are preferably selected in such a way that as much as possible falls to the share of the so-called condensate.

Plastics that can be processed by the proposed method are, for example, mixed fractions of undivided waste, for example, from the company Duale System Deutschland GmbH (DSD). These mixed fractions contain, for example, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polymer blends, like ABC plastic, and polycondensates. It is also possible to use waste from the production of plastics, industrial packaging from plastics, residual, mixed and pure fractions formed during the processing of plastics in industrial plants, and the chemical composition of these wastes is not a critical parameter determining their suitability for processing by the proposed method. Elastomers, rubber products for technical purposes or old tires in pre-crushed form are suitable for processing this method.

The source of plastic scrap and plastic waste are, for example, pressed products, laminates, compounds, films or synthetic fibers. Examples of halogen-containing plastics include chlorinated polyethylene (HPE), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), chloroprene rubber. In particular, sulfur-containing plastics, such as polysulfones or sulfur-crosslinked rubbers made from old tires, which are produced in large quantities, are used, which, with the appropriate equipment for preliminary grinding and preliminary sorting, are subjected to depolymerization and further processing for the production of chemical raw materials and Components of liquid fuel. The sulphide sulfur formed in this process in the preliminary stages of treatment or in chemical transformations with addition of hydrogen passes predominantly, like hydrogen chloride, into the exhaust gas, which is separated and fed for further processing.

Along with the plastic wastes and waste used in this method, synthetic plastics, elastomers, a and modified natural compounds can be used. These include, along with the already mentioned polymers, in particular thermoplastics, and thermosets and polyadducts, as well as cellulose-based products such as cellulose (fiber) and paper. Products made from them include semi-finished products, individual parts, building elements, packaging, storage and transport containers, as well as goods of mass demand. As for semi-finished products, panels and boards (printed circuit boards) fall into this category, as well as laminated plastic plates that may contain some part of metal coatings and can be, like other used products, after preliminary grinding up to the size of particles or pieces from 0.5 to 50 mm, separated if necessary from metal, ceramic and glass components by appropriate sorting methods.

These plastic waste and waste materials contain and, as a rule, inorganic impurities such as pigments, fiberglass, fillers, such as titanium oxide and zinc, flame retardants, pigment-containing inks, soot, as well as metals, such as metallic aluminum. The mentioned plastic waste and scrap, which are formed, for example, as mixtures or batch of different composition in the DSD waste collector, can contain up to 10, and in some cases up to 20% by weight, inorganic impurities. Typically, these plastics mixtures are used in the process of the invention in a pulverized form or pre-processed, for example, in the form of granules or chips or the like.

Depolymerization products according to the proposed method are mainly divided into 3 main streams:

1) Depolymerization in an amount of 15 to 85% by weight, based on the used plastic mixture, which, depending on the composition and the corresponding requirements, can be distributed over streams directed to liquid-phase hydrogenation, pressure gasification and / or, if necessary, Pyrolysis).

This is mainly about heavy hydrocarbons with a boiling point> 480 o C, which contain all inert substances, such as aluminum foil, pigments, fillers, fiberglass, that come with plastic wastes and waste.

2) Condensate in an amount of from 10 to 80, preferably from 20 to 50 wt. %, Based on the used plastic mixture, the boiling point of which lies in the range 25-520 ° C, and the content of organically bound chlorine is about 1000 ppm.

Condensate can, for example, be hydrotreated into stationary commercially available cobalt-molybdenum or nickel-molybdenum catalysts into high-quality synthetic crude oil (Syncrude) or as hydrocarbon-containing basic substances, directly introduced into chemical-technological or standard refinery processes that allow the presence of chlorine .

3) The gas in amounts of from 5 to 20% by weight, based on the used plastic mixture, which along with methane, ethane, propane and butane can contain gaseous hydrogen halides such as mainly hydrogen chloride, as well as highly volatile, chlorinated hydrocarbon compounds.

Hydrochloric acid can be washed out, for example, with water from a gas stream to obtain 30% aqueous hydrochloric acid. Residual gas can be liberated from organically bound chlorine by liquid-phase hydrogenation or treatment in a hydrotreater and sent, for example, to refinery refinery gas.

Separate product streams, in particular condensate, can be used as a separate feedstock, for example, as an initial material for the production of olefins on ethylene plants.

An advantage of the process according to the invention is that the inorganic admixtures of the plastic waste and scrap material are concentrated in the liquid phase, while the condensate without these components can be further processed by low-cost methods. In particular, by selecting the optimum process parameters-temperature and processing time-it can be achieved that, on the one hand, a relatively large fraction of the condensate is formed, and on the other hand, the viscosity of the viscous depolymerization of the liquid phase to pumping is maintained under the conditions of the proposed method. One suitable option is one in which raising the temperature by 10 ° C. with an average processing time increases the yield of the products passing into the liquid phase by more than 50%. The dependence of the yield on the duration of treatment for two typical temperatures is shown in Fig. 3.

With other preferred process embodiments, such as adding catalysts, stripping with steam, light boiling components or hydrocarbon gases, turbulent mixing or pumping, the condensate yield can be further optimized.

Typical for this method is condensate yield of about 50% by weight or more, based on the total amount of plastics used in the depolymerization. Due to this, an advantage is achieved, consisting in a significant unloading of the capital-intensive process steps, such as pressure gasification, liquid-phase hydrogenation, and pyrolysis.

In the process according to the invention, the preferred temperature range for the depolymerization process is 150 to 470 ° C. The most suitable range is from 250 to 450 ° C. The processing time can be 0.1 to 20 hours. In general, the range is up to 1 to 10 hours The pressure in the process according to the invention is less critical. Thus, it may be very advantageous to carry out the process under reduced pressure, for example, if for technical reasons the volatile components must be separated. In practice, it is possible to operate at relatively high pressure, but at the same time the operating costs associated with the use of expensive equipment increase. In general, the use of a pressure ranging from 0.01 to 300 bar, in particular from 0.1 to 100 bar, is permissible. The process can be carried out preferably at a normal or slightly elevated pressure, for example within a range of up to 2 bar, which clearly contributes to a reduction in operating costs. In order to degas the depolymerizate as much as possible and further increase the proportion of the condensate, the process is preferably carried out at a slightly reduced pressure to about 0.2 bar.

Depolymerization can be effected preferably by adding a catalyst, for example a Lewis acid, such as aluminum chloride, a radical-forming substance, such as peroxide, or a metal compound, for example a zeolite impregnated with a solution of some heavy metal salt.

Depolymerization can be carried out under turbulent flow conditions, for example, using a mechanical stirrer, but also by pumping the contents of the reactor.

Other preferred embodiments of the process are that the depolymerization is carried out in an inert gas environment, i. E. Gas which, with respect to the starting materials and depolymerization products, is generally inert, for example N 2 , CO 2 , CO or hydrocarbons. The process can also be carried out by introducing desorption media such as nitrogen, water vapor or hydrocarbon gases or other light boiling media.

In principle, it can be considered an advantage of the process that no hydrogen is added at this stage of the process.

As a solvent or a mixture of solvents, for example, organic solvents used, i.e. solvent waste, defective production batches of organic liquids, waste oils or fractions of refineries, eg a vacuum distillation residue, are suitable.

However, it is possible to refuse the addition of solvents, foreign oils and own recirculating oils.

Depolymerization can be carried out in a conventional reactor, such as a stirrer and external circulation boiler, which is designed for appropriate process parameters such as pressure and temperature, and whose capacities are made of a material resistant to acidic components such as hydrogen chloride, the formation of which is possible in The process of depolymerization. In particular, if depolymerization is carried out in the presence of a catalyst, it may be possible to consider the use of suitable standard chemical-technological operations for so-called light cracking of heavy crude oil or residual oils from the processing of mineral oils. If necessary, they must comply with the requirements of the method of the present invention. Preferably, this process step can be designed to operate in a continuous mode, i. E. The plastic is continuously fed into the liquid phase of the depolymerization reactor, and the depolymerization and the head product are continuously withdrawn.

The depolymerization process is not associated with high operating costs compared to subsequent processing steps, such as low-temperature, liquid-phase hydrogenation or gasification. This applies, in particular, to the case when the method is carried out at a pressure close to normal, i.e. In the range from 0.2 to 2 bar. And in comparison with the stages of preliminary hydroprocessing, operating costs are significantly lower. The optimal mode of the depolymerization process can relieve the subsequent process steps by 50% or more. At the same time, a large amount of condensed hydrocarbons is formed simultaneously during the depolymerization process, which can be processed into valuable products using known and relatively inexpensive methods.

It is very simple to operate with a depolymerizer after the separation of gas and condensate, since its consistency remains pumped, and in this form it is a convenient starting material for the subsequent stages of the process.

According to the invention, depolymerizate and condensate are treated separately.

The condensable depolymerization products are preferably hydrogenated on a stationary, granular catalyst. For example, condensate can be subjected to conventional hydrotreating using commercially available nickel-molybdenum or cobalt-molybdenum contact catalysts at a hydrogen partial pressure of 10 to 250 bar and a temperature of 200 to 430 ° C. In this case, depending on the composition of the formed Condensate to catch trapped ash or coke-forming components, it is advisable to connect a protective layer. The contact catalyst is arranged, as usual, on rigid plates, and the flow direction of the condensate can be provided either upstream of the hydrotreating column or in the reverse direction. To separate acidic components such as hydrogen halide, hydrogen sulphide and the like, it is advisable to supply water, alkaline compounds and, if necessary, corrosion inhibitors to the condensation zone of the respective separators.

The condensate, instead of the conventional hydrotreating, can also be subjected to hydrogenation treatment on a mobile catalyst or in a fluidized catalyst bed.

The condensate formed in the depolymerization after passing through the hydrotreater is an excellent starting material, for example, for cracking in the presence of steam.

The liquid product obtained, for example in a hydrotreater, is further processed as synthetic crude oil (Syncrude) in conventional refineries to produce liquid fuel components or is used as a chemical feedstock, for example for ethylene production on ethylene plants.

The gaseous components obtained during the hydrotreatment are suitable for the addition, for example, to the products used for the steam reforming process.

In one of the other preferred embodiments of the process, at least one depolymerization stream is pressurized.

As suitable for gasification under pressure devices, it is possible in principle to use aviation gas generators (Texaco, Shell, Prenflo), gasifiers with a stationary layer (Lurgi, Espag), and gasifiers Ziwi. In particular, methods for thermal degradation of hydrocarbons with oxygen are suitable, as is customary in the gasification method of the oil by partial oxidation of hydrocarbons in the form of a flame reaction in a combustion chamber. Reactions take place not catalytically, but autothermally.

The gas formed in gasification under pressure, consisting mainly of CO and H 2, can be processed into a synthetic gas or can be used to produce hydrogen.

In another preferred embodiment of the process, at least one depolymerization stream is supplied to liquid phase hydrogenation. Liquid-phase hydrogenation is preferred, in particular, if a high proportion of liquid hydrocarbons is to be obtained from the depolymerizate. The use of liquid phase hydrogenation for the production of gasoline and, if necessary, diesel fuel from crude oil is described in detail in DE 933 826.

Liquid-phase hydrogenation of the pumped viscous liquid depolymerizer can be carried out in such a way that, under certain conditions, a vacuum distillation residue is added, and after compression to 300 bar, hydrogenation gas is added as well. For preheating, the reaction mass passes through series-connected heat exchangers in which heat is transferred by product streams, for example to the hot product of the hot separator.

The reaction mixture, which is usually heated to 400 ° C., is heated further to the desired reaction temperature and then fed to the reactor or to the cascade of reactors, where liquid-phase hydrogenation occurs.

In the hot separator connected further, at the working pressure, the components at the reaction temperature in the gaseous state are separated from the liquid and solid components. The latter also contain inorganic impurities.

In the separator, the heavier oil components are first extracted from the gaseous fraction, which, after depressurization, can be fed to distillation at atmospheric pressure.

From the part that has not been condensed in this way, first the industrial gases that are processed for scrubbing in the scrubber are removed through the connected separator system and returned as a circulating gas back to the process. From the remaining part of the product after the hot separation, for example, after the subsequent cooling, the production water is removed, after which this part is fed to further processing in a column at atmospheric pressure.

Discarding the pressure in the bottom of the column of the hot separator in two steps, it is expedient to subject the product to a vacuum distillation to separate the residual oil. The thickened residue, and containing inorganic impurities, can be sent in a liquid or solid form to a gasification unit for the production of a process gas.

The residues (residues of hot separation) formed during the liquid-phase hydrogenation, and the semi-coke produced during the depolymerization of depolymerizate, containing inorganic impurities, respectively, can be disposed of in the subsequent thermal stage of the process, the residues containing inorganic impurities resulting therefrom can be further reduced Processing.

The light and medium petroleum fractions obtained by liquid-phase hydrogenation can be used in refineries as a valuable raw material for the production of fuels or starting materials for the production of plastics such as olefins or aromatics. If these liquid-phase hydrogenation products prove to be unstable during storage, they can be subjected to a hydrotreatment provided by this condensate process.

A preferred embodiment of the process according to the invention is that the pumped viscous depolymerizate, after separating the gaseous and condensable depolymerisation products, is separated as a liquid product into streams, one of which must be supplied for gasification under pressure and the other for liquid-phase hydrogenation.

According to the invention, the separation of the pumped viscous depolymerizate into streams, one of which must be fed to gasification under pressure, and the other to hydrogenation and, if necessary, pyrolysis, in combination with the separate treatment of the condensable components in the hydrotreating step leads to a significant improvement in the use of the equipment. With regard to installations designed for gasification under pressure of solid combustible materials or thermal decomposition of hydrocarbons by means of oxygen, in particular installations for liquid-phase hydrogenation of carbon-containing materials under high pressure, in this case it is a question of capital-intensive units of plants, the productivity of which can only then Be used optimally if they are freed from the need to process the raw materials, as suggested in this method, when hydrocarbons are preliminarily separated as a condensate stream and subjected to separate treatment in a hydrotreater under relatively mild processing conditions.

A further preferred embodiment of this method is that at least one depolymerizate stream is subjected to a freeze-up to produce a semi-coke gas, a semi-coking pitch and a char.

The condensed hydrochloric gas formed in the depolymerization of gaseous in the form of an aqueous solution can be used separately as an independent product for disposal. Residual fractions that are not components of depolymerization products that are converted to a gaseous state and condensed in the form of liquid products and which can contain, in particular, chloroorganic, as well as sulfur and nitrogen containing compounds, are released during liquid-phase hydrogenation, by including The stage of processing residues from chlorine, sulfur, nitrogen or oxygen heteroatoms, which are separated as hydrogen compounds.

Often, because of the significant content of halogens in the initial plastic waste, it is preferable to wash the distilled gaseous products of depolymerization, the hydrogen halides formed in particular being separated as aqueous halogenated acids and directed to disposal.

The gaseous products of depolymerization, which have been freed from acidic components, such as hydrogen halides, if necessary, can be supplied preferably to the hydrogen gas feedstock or to the circulating hydrogen gas of liquid-phase hydrogenation. The same applies to the semi-coke gas, which is separated during the reaming.

Due to the combination of depolymerization processes, hydrogenation treatment of the distillate components obtained by the proposed method, liquid-phase hydrogenation, gasification (partial oxidation) and / or melting of the liquid phase depolymerization, it is possible to unload the technologically most capital-intensive and complex processing steps allowing work with inorganic ingredients. The process according to the invention has a great potential for recycling the used plastics.

Thus, the selected combination of the described process steps can provide almost complete utilization of the organic carbon contained in the plastics used. In addition, it is possible to largely utilize the carbon and hydrocarbon components contained in the waste plastics used. The remaining inorganic components can be recycled, for example metal regeneration. They can also be re-used, at least in part, in the grinded form as a catalyst in a liquid-phase hydrogenation process.

METHOD FOR PROCESSING PLASTIC WASTE AND PLASTIC WASTE

The process according to the invention with the main process units of the depolymerization unit, the hydrotreater, the pressurized gasification plant, the liquid phase hydrogenation columns, the low-temperature plants and the units for treating the gaseous depolymerization products is shown in FIG. 1. In this figure, the dashed line shows the configuration of the device with the installation for the lowering as a selectively provided unit of the device. The separation of the respective products into streams is shown in the diagram using appropriately directed lines. The positions in Fig. 1 have the following values: 1 - depolymerization reactor, 2 - hydrotreater, 3 - liquid-phase hydrogenation, 4 - gasification unit, 5 - low-temperature plant, 6 - plastic waste, 7 - vacuum distillation residue, 8 - hydrochloric acid, 9 - gases (methane , Ethane, propane, H 2 , etc.), 10 - condensate, 11 - depolymerizate, 12 - gases (methane, ethane, propane, H 2 S, NH 3 , H 2 , etc.) (for example, For steam reforming), 13 for Syncrude II (for example for an olefin plant), 14 for process gas (CO / H 2 ), 15 for slag, carbon black (for example, for metal regeneration), 16 for gases (methane, ethane, propane , H 2 S, NH 3 , H 2 , etc.) (for example for steam reforming), 17 - Syncrude I (for example for refining), 18 - hydrogenation residue (for example for gasification), 19 - gases (For example, for liquid-phase hydrogenation), 20-tar (for example, for liquid-phase hydrogenation), 21-coke (for example, for gasification installation).

Scheme of quantitative consumption of products for the product shown in FIG. 1 of the equipment is given below in the form of an example of performance for said starting products.

Accordingly, the crushed, if necessary washed and dried plastic waste is continuously fed to a depolymerization reactor 1 equipped with heating, pressure maintaining and agitating means, corresponding inlet and outlet valves, and monitoring and measuring equipment for level control.

In a typical embodiment, 50.0% by weight of depolymerizate, 40.0% % Of condensate, 5.0% by weight of hydrogen chloride gas and 5.0% by weight of other gases, based on the total reaction mass. Condensate is fed to the hydrotreater 2, through the top of which 35.0 wt. % Syncrude fed to the olefin plant, a and 5.0% by weight of the gaseous reaction products that are fed to steam reforming.

25.0 wt. % Of the depolymerizer is fed to the liquid-phase hydrogenation 3 and 25.0% by weight to the gasification unit 4. A further 25.0% by weight of the vacuum distillation residue in the form of a recycle stream is supplied to the liquid-phase hydrogenation 3. 10.0% by weight of gaseous reaction products are fed to the steam reforming, 40.0% by weight of Syncrude fed to the refinery complex and 5.0% by weight of the residue that can be diverted to the gasification unit 4. The reaction product From the gasification plant and under a typical operation regime it consists of 24% by weight of the process gas, and 1.0% by weight of the ashes.

A stream of depolymerizer exiting the reactor 1 to produce pyrolysis coke, a semi-coke tar and a semi-coking gas may optionally be supplied to the pyrolysis or pyrolysis unit 5, respectively. Pyrolysis coke is fed to a gasification plant, a semi-coking tar and a semi-coking gas for liquid-phase hydrogenation.

The inorganic impurities enriched in depolymerization are subjected to subsequent processing of the further concentration. If depolymerizate is fed for gasification, the inorganic impurities are then removed together with the slags. In liquid-phase hydrogenation, they are present in the hydrogenation residue, and in the case of the solidification in the semi-coke. If the hydrogenation residue and / or semi-coke is hydrogenated, all the inorganic impurities introduced into the process according to the invention are discharged in the processing step in the form of gasification slags.

In Fig. 2 shows a preferred embodiment of a loading unit for plastic waste and plastic waste depolymerization plant with its associated processing unit for gaseous as well as condensable products of depolymerization. The positions in FIG. 2 have the following meanings:

1 - bunker for plastic waste, 2 - depolymerization reactor, 3 - furnace, 4 - circulation pump, 5 - slurry pump, 6 - feed tank, 7 - high pressure pump, 8 - condenser, 9 - hydrochloric acid scrubber 10 for gases, 11 for fresh water, 12 for aqueous hydrochloric acid, 13 for condensate (for example for a hydrotreater), 14 for a vacuum distillation residue, 15 for a mixture of depolymerization with a vacuum distillation residue (for example for liquid-phase hydrogenation) Conveying device.

Through the conveying device 16, plastic waste and waste materials enter the hopper 1 and from there to the reactor 2. The heating of the reactor contents is carried out by means of a circulation system consisting of a circulation pump 4 and a furnace 3. A pump 5 for transferring suspensions from this cycle takes a stream which is mixed In the feed tank 6 with the vacuum distillation residue coming through the line 14 and then fed to a subsequent processing with a high pressure pump 7. The gases produced in the reactor 2 and the condensable components pass through the condenser 8 and are separated. After passing through the scrubber 9 with hydrochloric acid, the purified gases 10 are used for further use. The previously retained acidic components are removed after washing in the form of an aqueous solution of hydrochloric acid 12. The condensate separated in condenser 8 is supplied for further use.

Example 1. Depolymerization of plastics waste.

A mixed agglomerated plastic particle with an average grain diameter of 8 mm was continuously loaded pneumatically at a rate of 5 t / h into a boiler-reactor with an 80 m 3 stirrer equipped with a 150 m 3 / h circulation system. Mixed plastics are a material of household origin of the firm Dualen Systems Deutschland, which contains, as a rule, 8% PVC.

The plastic mixture was depolymerized in the reactor at a temperature of 360 ° C to 420 ° C. Four fractions were thus formed, the quantitative ratio of which, depending on the temperature in the reactor, is shown in Table. 1.

The depolymerization stream (III) was withdrawn continuously and, together with the vacuum distillation residue, was fed to a liquid phase hydrogenation unit for further cleavage. The viscosity of the depolymerizate was 200 mPas at 175 ° C.

In a separate installation, the hydrocarbon condensates (stream II) were condensed and fed to further appropriate processing in the hydrotreater. Gaseous hydrogen chloride (stream IV) was dissolved in water and obtained as a 30% aqueous hydrochloric acid. Hydrocarbon gases (stream I) were supplied for conditioning to a liquid phase hydrogenation unit.

EXAMPLE 2 Dechlorination of Condensate

From the condensate of the depolymerization plant, which was obtained at a temperature of 400-420 ° C from a mixture of plastics (DSD-household waste), HCl was isolated by washing with an ammonia-alkaline solution. The content of chlorine in the condensate was 400 ppm.

This pre-treated condensate was subjected to a catalytic dechlorination process in continuous apparatuses. The condensate was first compressed to 50 bar and then saturated with hydrogen so that the gas / condensate ratio was maintained at 1000 l / kg. The mixture was heated and subjected to exchange decomposition in a reactor with a fixed NaMo-catadizer. Coming out of the reactor, the reaction mixture was quenched with ammonia-alkaline water, so that the resulting HCl completely passed into the aqueous phase. Before the pressure was released in the reaction mixture, the phases were separated into gas and liquid, so that the gas and liquid phases could be relaxed separately. After relaxation, the liquid phase was decomposed into aqueous and organic phases.

The organic phase, the amount of which left more than 90% by weight of the initial condensate, contained, depending on the chosen reaction conditions, the following amounts of chlorine [parts per million] (see Table 2).

These types of condensate correspond under any reaction conditions to the input specifications of the mineral oil purification plant and can be fed into stripping of light ends or to special processing units (for example, to a steam cracker).

CLAIM

A method for processing plastic scrap raw materials or plastic wastes to produce chemical feedstocks and liquid fuel components by depolymerizing starting materials without the addition of hydrogen to produce a volatile phase and depolymerization in the form of a pumped phase, characterized in that the volatile phase is divided into a gas phase and a condensate which Are subjected to standard refinery processes, and the pumped phase is subjected to liquid-phase hydrogenation, gasification, or combination of these technological operations.

2. A process according to claim 1, characterized in that the depolymerization is carried out at a pressure of 0.01 to 300.0 bar, preferably 0.1 to 100.0 bar, in particular 0.2 to 2.0 bar, at 150 to 470 O C, preferably 250-450 ° C, and a reaction time of 0.1 to 10.0 hours, preferably 0.5 to 5.0 hours, and that three product streams are withdrawn in amounts of 15 to 85 weight percent depolymerization, 80% by weight,% of the condensate, a and 5-20% by weight of the gas mixture, each in terms of the initial mixture of plastics.

3. A process according to claims 1 and 2, characterized in that the depolymerization is carried out in the presence of a catalyst.

4. A process according to at least one of the preceding claims, characterized in that the depolymerization is carried out under turbulent flow conditions.

5. A process according to at least one of the preceding claims, characterized in that the depolymerization is carried out in an inert gas environment.

6. A process according to at least one of the preceding claims, characterized in that the depolymerization is carried out using desorption media such as nitrogen, water vapor, hydrocarbon-containing gases or other low-boiling media.

7. A process according to at least one of the preceding claims, characterized in that an organic solvent is added to the raw plastic waste or plastic scrap material, such as solvent waste, defective production batches of organic liquids, waste oils recycled during the oil process or Fractions of oil refineries.

8. A process according to at least one of the preceding claims, characterized in that the condensate is subjected to a hydrogenation treatment on a fixed catalyst.

9. A process according to at least one of the preceding claims, characterized in that the condensate is subjected to hydrogenation treatment on a mobile catalyst or in a fluidized catalyst bed.

10. A process according to at least one of the preceding claims, characterized in that the gaseous depolymerization products are fed to a liquid phase hydrogenation, with a scrubber, if necessary, connected to remove acidic components such as hydrogen chloride.

print version
Date of publication 22.12.2006гг