RU2014346C1 - Method of processing wastes - Google Patents

Abstract

FIELD: processing wastes. SUBSTANCE: wastes are heated to 350-1050 C and treated by gasifying agent till content of organic compounds is less 100 g per 1 t. Thus produced gas mixture is decomposed at 950-1050 C within 1 s. Thus prepared low-molecular compounds and/or elements are separated into synthesis gas and low-molecular compounds and/or elements. This process is carried out in water at 200-800 C. Wet synthesis gas is treated in the presence of catalyst. EFFECT: improves efficiency of the method. 12 cl, 2 dwg

Description

 The invention relates to a method for processing waste arising in the production and consumption process.

 There is a known method of processing waste, such as municipal waste, sewage sludge, etc., by treating the waste at a temperature of about 900 ° C with a gaseous mixture containing steam and at least one combustible gas, oxygen and / or CO2. However, this method is not effective enough.

 The aim of the invention is to increase the efficiency of waste processing.

 This goal is achieved by this method, including the stage of gasification by treating the waste by heating with a gasifying agent containing water vapor and at least one combustible gas: oxygen and carbon dioxide, to obtain a gas mixture and solid inorganic products, and the waste is heated to 350-1050 ° C. and treatment with a gasification agent is carried out until the organic matter content in the waste is below 100 g per 1 ton of waste, the resulting gas mixture is subjected to cleavage at 950-1050 ° C for 1 s into low molecular weight compounds The solutions and / or elements are introduced into water at 200-800 ° C for separation into synthesis gas and low molecular weight compounds and / or elements held by water, wet synthesis gas is treated in the presence of a catalyst to produce liquid hydrocarbons and / or alcohols, gaseous hydrocarbons and carbon dioxide , gaseous hydrocarbons and carbon dioxide are mixed with a gasification agent supplied to the gasification step.

 Moreover, at least one, preferably two source materials selected from the group consisting of: land, in particular land contaminated with solvents, oil, tar or heavy metals, as well as components of the earth contaminated with organic and inorganic substances, for example, are used as waste materials. construction waste, or sand, coal contaminated with heavy metals and / or precious metals, in particular coal with a high sulfur or lignin content, activated carbon saturated with solvent vapors; slag, in particular, slag from industrial furnaces, blast furnaces, thermal power plants or waste incinerators; dust, in particular dust retained by electrostatic precipitators, or dry residues of wet, semi-dry or dry flue gas cleaning of waste incineration plants or industrial furnaces; sludge, in particular sewage sludge, or sludge from heavy metals contaminated with sewage treatment plants, sludge from galvanic plants, sludge arising from the production of ammunition and explosives, as well as residues from solvent distillation and paint and varnish production; food products, in particular residues, surpluses and by-products arising in the process of production and consumption of food products, in particular coffee grounds, slaughterhouse waste; chemical wastes, in particular by-products of chemical or biological analyzes or processes, in particular filter residues, unusable non-flowing chemicals or laboratory wastes with weak radioactivity; organs, in particular corpses of dead animals, tissue and blood material from the surgical sphere, solid residues from hospitals, in particular unsuitable medications; rubber and plastics, in particular pneumatic tires, elastomers bonded or mixed with metallic or other inorganic materials, thermoplastics and thermosets.

 Moreover, as waste use a mixture delayed by dust and sewage filters, a mixture of dust and coal detained by filters, a mixture of sand, sewage and coal.

 Moreover, at least one, preferably two, starting material selected from the group consisting of: oils and paraffins, for example heavy oil or paraffins, in particular those obtained from the distillation of oil or from the processing of used oil, is used as waste; alcohols and ketones, for example methanol, ethanol and industrial coal, acetone; halogenated hydrocarbons, for example trichloroethane, trichlorethylene, chloroform, and chlorinated aromatic compounds, in particular chlorobenzenes or polychlorobiphenyls, furans or dioxins, or freon, in particular freon 113; inorganic liquids, for example mineral acids and bases, heavy metals, and not containing them, in particular hydrochloric acid, dissolved ferric chloride and chromic sulfuric acid, as well as dissolved cyanides, natrides, nitrates and phosphates.

 Moreover, the following mixtures are used as waste: waste oil-chlorinated hydrocarbon and mixture: sand-sediment of waste water-halogenated hydrocarbon.

 Preferably, the gas mixture obtained in the gasification step contains 10-40 vol.% Water vapor, 10-40 vol.% Combustible gas, especially methane, 5-20 vol.% Oxygen and 30-70 vol.% Carbon dioxide.

 The duration of the gasification reaction for mixtures of liquid materials is from 0.5 to 3 s, and for mixtures of solid materials from 20 minutes to 2 hours

 At the same time, harmful gases, such as flue gases from furnaces, exhaust gases from internal combustion engines and exhaust air from ventilation shafts, are mixed in at the gasification stage of the gas mixture.

 And the stage of gasification of mixtures of liquid materials is carried out in a gas burner operating on a mixture of synthesis gas and water vapor obtained in the separation stage.

 Moreover, the gasification stage with mixtures of solid materials and sludge is carried out in a furnace for solid materials using synthesis gas and water vapor obtained in the separation stage.

 At the gasification stage, oxygen is used, which is the residual oxygen contained in the exhaust air stream, internal combustion engines or in the exhaust air of ventilation units.

 At the separation stage, water is used, which is waste water, water leaking from landfills, contaminated water or seawater.

 The method according to the invention is more precisely explained below using a flowchart (see figure 1). The required mixture of materials using transport screws 1 is taken from three storages 2 for materials or storages 3 for sludge and fed into the converter 4. In the converter 4 through the pipeline 5 is also fed a mixture of carbon dioxide with approximately 10 vol.% Oxygen, and through the control valve 6 bring the necessary combustible gas mixture. The steam generator 7 additionally supplies 4 pairs to the converter. The gas mixture arising in the converter 4 is freed in the cyclone 8 from particles, which are then returned to the material stream. The gas mixture freed from particles is passed through a pipe 9 and an inlet ring 10 to a gas scrubber 11. The washed gas mixture passes a cooler 12, which condenses water vapor and precipitates it into a feed water tank 13. Pump 14 delivers a small amount of feed water to the sprinkler 15 in the scrubber to cool and improve the cleaning effect. The main part of the feed water is spent on cooling the wave reactor 16, so that it enters the steam generator 7, preheated. The gas compressor 17 compresses the washed synthesis gas to a pressure of about 5-20 bar and delivers it to the wave reactor 16. Here an exothermic synthesis reaction occurs, producing water vapor, carbon dioxide, gaseous hydrocarbons containing, in particular, propane or butane. Initially, the gaseous mixture is supplied to the distillation tank 18, and thereby, water and propane or butane are condensed by cooling; propane or butane is collected in the tank 20. Water is supplied to the cells of the electrolyzer 19, and from there to the tank 13 for feed water. Gaseous products through a pipe 21 together with electrolysis hydrogen are supplied to the steam generator 7 and the converter 4. The steam generator 7 is controlled so that the gas pressure is in the required range of 8-10 bar and that its exhaust outlet gases there is a sufficient amount of excess oxygen to maintain the temperature in the Converter 4.

 Water from the distillation tank 18 is sent through the cells of the electrolyzer 19 to the feed water tank 13. The cooler 12, the distillation tank 18 and the converter 4 are cooled through a separate water cooling circuit with an inlet of cooling water (KE) and an outlet of cooling water (KA), which Using an external water-water or water-air heat exchanger transfers heat to the consumer.

 The solid product obtained in converter 4, depending on its quality, is fed by transport augers 25 for storage into one of the three bins 26 until distribution. The resulting brine is stored in the tank 27 until further processing. The insoluble sludges obtained in the scrubber are separated from the brine in the sludge tank 28 and returned, after or without intermediate processing, to the sludge storage 3.

 The following embodiments illustrate the method according to the invention.

 PRI me R 1. The dust retained by the filters, consisting of 65 wt.% Sewage sludge containing 40 wt.% Dry matter, and 35 wt.% The dust retained by the filters, which came from the plants for wet cleaning of waste products of waste, served into the converter and at a temperature of 850-1000 ° C for 0.5 h ("residence time") is subjected to the action of a stream consisting of 30 vol. % steam, 10 vol.% methane, 10 vol.% hydrogen, 45 vol.% carbon dioxide and 5 vol.% oxygen. The cells of the electrolyzer supply 160 nm3 of air and 80 nm3 of oxygen per 1 ton of the mixture of processed materials at a consumption of 720 kWh of electricity. The steam generator delivers 480 nm3 of saturated steam at a pressure of 10 bar, and the gas flow rate corresponds to about 30 nm3 of synthesis gas or hydrogen. A total of 460 nm3 of synthesis gas is obtained and 80 kg of butane are extracted from it. In general, according to the method of processing the dust detained by the filters, 650 kg of sewage sludge were gasified and 350 kg of the dust retained by the filters were decontaminated, and the electric power consumption was 720 kWh with a butane output of 80 kg (960 kWh of stored energy).

 PRI me R 2. For gasification of oils, especially halogenated hydrocarbons (see figure 2), the Converter 24 is made as a gas burner and runs on synthesis gas coming from the gas scrubber 29, which branches off before the cooler 30. Through the compressor 31 converter 24 is supplied with air heated to a temperature of about 400 ° C by a hot synthesis gas pipe 32 concentrically surrounding the air flow. From the oil tank 33 provided with a stirrer 34, oil is supplied to the burner through the valve 35, which evaporates in a preheated air stream, and the resulting vapor is sucked in by a gas flame. Since the synthesis gas coming from the scrubber 429 contains approximately the same volumetric part of the water vapor, and the mixture in the heat exchange 36 is greatly heated by the cracking gas at the outlet of the converter 24, efficient gasification of the oil is ensured. Synthesis gas can be directly used for heating or driving engines, and also transferred to thermal power plants. When working with chlorinated or fluorinated oils, soda or metal hydroxide must be added to the feed water in the feed water tank 37 to neutralize the resulting hydrochloric acid. Depending on the quality of the oils used and the process control, the resulting hydrochloric acid can also be obtained directly from the brine tank 38. In the processing of chlorinated oil with a chlorine content of about 30 wt.% Per 1 MWh of calorific value, 300 nm3 of synthesis gas is obtained with an air requirement of approximately 170 nm3. Syngas mixed with nitrogen has a fraction of about 70 vol. %, and the calorific value of about 2 kWh per 1 nm3. The sludge remaining during the processing of the oils in the tank 33 or in the tank for sludge 39 can be treated in the same way as sewage sludge.

 In the production of coffee or spice extracts, waste arises that cannot be used as animal feed or as fertilizer. These materials can be converted into synthesis gas or methane or butane by the method proposed in the invention.

 Thus, the proposed method allows for the radical destruction of undesirable compounds or components by means of a thermochemical reaction with water vapor or equivalent reagents. It provides for the rehabilitation or uselessness of landfill and high-temperature incineration due to the full use of the materials and energies used.

Claims (12)

1. WASTE PROCESSING METHOD, including the step of gasification by treating waste by heating with a gasification agent containing water vapor and at least one combustible gas: oxygen and carbon dioxide, to obtain a gas mixture and solid inorganic products, characterized in that, in order to increase the efficiency of the process, the heating of the waste is carried out up to 350 - 1050 ^o С and the treatment with a gasifying agent is carried out until the organic matter content in the waste is below 100 g / t of waste, the resulting gas mixture is subjected to splitting at 950 - 1050 ^o С within 1 s, low molecular weight compounds and / or elements, low molecular weight compounds and / or elements are introduced into water at 200 - 800 ^o C for separation into synthesis gas and low molecular weight compounds and / or elements held by water, wet synthesis gas is treated in the presence of catalyst to produce liquid hydrocarbons and / or alcohols, gaseous hydrocarbons and carbon dioxide, gaseous hydrocarbons and carbon dioxide are mixed with a gasification agent supplied to the gasification step.  2. The method according to claim 1, characterized in that at least one, preferably two, source materials selected from the group consisting of earth, in particular land contaminated with solvents, oil, tar or heavy metals, are used as waste. as well as components of the earth contaminated with organic and inorganic substances, for example construction debris or sand contaminated with heavy metals and / or noble metals; coal, in particular coal with a high sulfur or lignin content, activated carbon saturated with solvent vapor, slag, in particular slag from industrial furnaces, blast furnaces, thermal power plants or waste incinerators; dust, in particular dust or dry matter retained by electrostatic precipitators, wet, semi-dry or dry flue gas cleaning of waste incineration plants or industrial furnaces; sludge, in particular sewage sludge or heavy metal contaminated sludge from sewage treatment plants, sludge from galvanic plants, sludges arising from the production of ammunition and explosives, as well as residues from solvent distillation and paint and varnish production; food products, in particular residues, surpluses and by-products arising in the process of production and consumption of food products, in particular coffee grounds, slaughterhouse waste; chemical wastes, in particular by-products of chemical or biological analyzes or processes, in particular filter residues, unusable non-flowing chemicals or laboratory wastes with weak radioactivity; organs, in particular the bodies of dead animals, tissue and blood material from the surgical sphere, solid residues from hospitals, in particular unsuitable medications; rubber and plastics, in particular pneumatic tires, elastomers bonded or mixed with metallic or other inorganic materials, thermoplastics and thermosets.  3. The method according to claims 1 and 2, characterized in that the waste used is a mixture of dust and sediment trapped by filters, a mixture of dust and coal trapped by filters, a mixture of sand, sewage sludge and coal.  4. The method according to claims 1 to 3, characterized in that at least one, preferably two, starting materials selected from the group consisting of oils and paraffins, for example heavy oil or paraffins, in particular obtained by distillation of oil or in the processing of used oil; alcohols and ketones, for example methanol, ethanol and industrial coal, acetone; halogenated hydrocarbons, for example trichloroethane, trichlorethylene, chloroform, and chlorinated aromatic compounds, in particular chlorobenzenes or polychlorobiphenyls, furans or dioxins, or freon, in particular freon 113; inorganic liquids, for example mineral acids and bases, containing and not containing heavy metals, in particular hydrochloric acid, dissolved ferric chloride and chromic sulfuric acid, as well as dissolved cyanides, nitrites, nitrates and phosphates.  5. The method according to claims 1 to 4, characterized in that the waste is a mixture of used oil - chlorinated hydrocarbon and a mixture of sand - sewage sludge - halogenated hydrocarbon.  6. The method according to claims 1 to 5, characterized in that the gas mixture obtained at the gasification stage contains 10 to 40 vol.% Water vapor, 10 to 40 vol.% Combustible gas, in particular methane, 5 to 20 vol.% Oxygen and 30 to 70 vol.% carbon dioxide.  7. The method according to PP.1 to 6, characterized in that the duration of the gasification reaction for mixtures of liquid materials is 0.5 to 3.0 s, and for mixtures of solid materials from 20 minutes to 2 hours  8. The method according to claims 1 to 7, characterized in that harmful gases, such as flue gases from furnaces, exhaust gases from internal combustion engines and exhaust air from ventilation shafts, are mixed into the gas mixture obtained at the gasification stage.  9. The method according to claims 1 to 8, characterized in that the stage of gasification of mixtures of liquid materials is carried out in a gas burner operating on a mixture of synthesis gas and water vapor obtained in the separation stage.  10. The method according to claims 1 to 9, characterized in that the stage of gasification with mixtures of solid materials and sludge is carried out in a furnace for solid materials using synthesis gas and water vapor obtained in the separation stage.  11. The method according to claims 1 to 10, characterized in that at the stage of gasification, oxygen is used, which is the residual oxygen contained in the exhaust air of the furnaces, internal combustion engines or in the exhaust air of ventilation units.  12. The method according to PP.1 to 11, characterized in that at the separation stage use wastewater leaking from landfills, infected or marine.

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