RU2805335C1 - Method for thermochemical treatment of sludge waste in a transonic flow - Google Patents

Abstract

FIELD: environmental protection.

SUBSTANCE: thermochemical treatment of sewage sludge from wastewater treatment plants with a high moisture content, can be effectively used in the implementation of measures to protect the environment from pollution. The process is carried out sequentially in three parallel channels, with division into temperature ranges of transonic flotations with speeds of 1000 m/s. The first workflow with a temperature of 1600°C is generated by burning kerosene in compressed atmospheric air, into which treated sludge waste is introduced, and is treated in a shock wave system at a temperature of 280°C with a gas-vapor mixture of low-boiling hydrocarbons in the reaction chamber. The second workflow with a temperature of 2600°C is generated by burning kerosene in an aqueous solution of ammonium nitrate and the reaction products of the first stage purified from low-boiling hydrocarbons are introduced into it. At a temperature of 1500°C, liquid mixture of aqueous solutions and hydrocarbon components is treated in a chamber for separating chemically active and passive substances. The third workflow with a temperature of 3500°С, generated by burning kerosene in technical oxygen for processing the solid dispersed fraction of inorganic components, is cooled in the shock wave system to 2715°C, reaching the melting temperature of metals in the chamber for the separation of chemically passive substances.

EFFECT: expanding the scope of transonic combustion for processing multi-grade complex waste, reducing the volume of waste, simplifying the neutralization process by simplifying the preparatory stages for the dehydration of sludge waste.

4 cl, 2 tbl, 2 ex, 1 dwg

Description

The invention relates to the field of ecology and environmental protection, in particular, to the thermochemical recycling of sludge waste from sewage treatment plants and can be effectively used in implementing measures to protect the environment from pollution, by carrying out thermochemical treatment of multicomponent multifractional industrial and municipal sludge waste with high moisture content, including fuel components and a wide range of chemically active and passive substances.

As a result of human economic, household and industrial activities, during the process of wastewater passing through treatment stages at treatment plants, sludge is formed, which, when processed, provides for a maximum reduction in humidity and volume, stabilization and disinfection in order to remove them from the territories of wastewater treatment facilities. Depending on the type of structures used for wastewater treatment, sludge sediments are: coarse, retained by grates; heavy (sand), settling in sand traps; floating (fats and mechanical impurities), retained in settling tanks and grease traps; raw sludge - mainly suspended solids settling in primary settling tanks; activated sludge is a complex of colloidal microorganisms with adsorbed and partially oxidized pollutants that fall out in secondary settling tanks during biological wastewater treatment.

On average, sludge from wastewater treatment plants consists of organic (up to 80% combined with moisture content) and mineral (about 20%) impurities isolated from water as a result of mechanical, biological and physicochemical treatment. They contain substances that have general toxic, toxicogenetic, embryotoxic, carcinogenic and other negative properties. They may contain heavy metals, pathogenic organisms, excess amounts of nitrates, toxic substances, aliphatic compounds, ethers, mono- and polycyclic aromatic substances, phenols. The composition of sludge varies widely and depends on the presence of industrial enterprises and the efficiency of their wastewater disposal systems with local treatment before being discharged into the sewer network.

The problem is particularly acute due to the accumulation of significant quantities of high-ash, highly water-saturated, low-calorie sludge waste, which is hazardous to the environment and human health when released into water, soil, or air. Their processing is difficult with traditional thermochemical methods and means, both due to the high costs of transporting waste and the problems of their disposal at landfills due to high energy costs and restrictions imposed by law. The amount of sludge accumulated over many years as a result of the operation of treatment facilities is rapidly increasing every year.

There is a known method of sludge waste disposal, which consists of mechanical dewatering. Sludge waste (their initial moisture content is 98÷99%) is stored in special sludge piles, in which their biodegradation takes place over a long period of time. The dewatered raw sludge is then collected and stored in city landfills. [Turovsky I.S. Treatment of sewage sludge. M. Stroyizdat, 1988. - 257 p.]. The advantage of this method is the relatively insignificant new formation of microbial biomass. The disadvantage of this method is its imperfection, duration, low productivity, and this method requires the alienation of significant land plots near sources of pollution. In addition, sludge waste storage facilities pose a threat to the environment, since in addition to various organic substances, it may contain heavy metals that pollute the environment. There are known methods for burning sludge waste in special furnaces, by thermal action on multicomponent chemical compounds carried out in a closed volume, for example, a method and device for the joint combustion of waste and semi-dry waste sludge (Patent RU 2741936 C1, M. Class F23G 5/04, C02F 11/10, F23G 7/00, published 01/29/21) using grate waste heat boilers containing a drying section, a pyrolysis section, a fixed carbon-burning section and a fixed carbon-outgassing section. This method has a fairly high productivity and the ability to produce steam capable of driving a turbogenerator to generate electrical energy. The disadvantages of this method include the use of incinerators with grates or other furnaces (with fluidized bed boilers, rotary kilns and catalytic combustion units) and are limited by excessive material and financial costs for equipment and operating costs associated with the requirements for preliminary multi-stage preparation of raw materials (organization of evaporation , grinding) and final multi-stage (from three to six) exhaust gas purification.

A known method for recycling sludge waste uses pyrolysis processing, for example, a method for processing oil-containing waste (sludge) [Patent RU 2611870 C1 M. Cl. C02F 11/10, C02F 11/18 publ. 01/10/17] for the purpose of using waste as recyclable materials, and extracting valuable hydrocarbon components from them (obtaining boiler fuel for the pyrolysis process) and obtaining useful products. This method makes it possible to obtain gaseous fuel and raw materials for construction materials. The disadvantages of this method include the need for a costly stage of waste preparation: grinding with the removal of large inorganic inclusions and unbound water, due to the ash content, moisture content, calorie content, and associated energy costs exceeding the permissible limits. In addition, the processing of multi-component waste into gaseous boiler fuel is rapidly losing its relevance due to the significant tightening of environmental requirements for fuels. There is also a need to use complex exhaust gas purification systems, because waste may contain heavy metals. Despite the variety of ways to solve the problem of sludge waste disposal, as well as the well-developed technical side of this issue, practice shows the inevitability of too large material costs for the creation of treatment facilities, as well as the need to allocate large areas for these structures and significant costs for transporting sludge waste. Most of these traditional approaches and solutions, which have many years of experience in practical use, often turn out to be ineffective, complex or simply unacceptable. The presence of open sludge ponds, aeration tanks that lead to unpleasant odors, and the appearance of a large amount of sludge sediments that need to be disposed of also indicate the need to search for alternative methods of sludge waste disposal.

The closest to the claimed technical solution is a method for thermochemical neutralization of highly toxic substances [Patent RU 2005519 C1, M. Cl. A62D 3/00, publ. 01/15/1994], including mixing the substance to be neutralized and a high-temperature high-speed flow of working gas, thermochemical decomposition of the substance to be neutralized at a temperature of 2000°C-3500°C with the formation of reaction products with their subsequent afterburning and the introduction of chemical reagents that ensure the complete passage of chemical reactions with the formation of final non-toxic compounds. In this method, mixing the neutralized substance with a high-temperature gas is carried out by exposing the neutralized substance to a transonic - supersonic flow with a Mach number M = 0.9-2.0 at a temperature of ≥2000°C, after which the resulting mixture is burned in the reaction chamber at an oxidizer excess coefficient α≥1.1 until of the final reaction products, and then stepwise introduce chemical reagents, which, after mixing with the final reaction products, are combined into a volume with an aqueous solution of the absorber.

Disadvantages of the method implemented in the patent [Patent RU 2005519 C1, M. Cl. A62D 3/00, publ. 01/15/1994], eliminated in the method of thermochemical neutralization of highly toxic substances [Patent RU 2240850 C1, M. Class. F23G 5/04, C02F 11/10, F23G 7/00 publ. 11/27/2004 (prototype)], which is adopted as a prototype in the proposed invention. The method of thermochemical neutralization of highly toxic substances is characterized by the fact that the substance to be neutralized is subjected to a multi-stage processing process in a high-temperature high-speed gas flow by thermochemical decomposition at 2000-3500°C with the formation of reaction products, their afterburning and the introduction of chemical reagents, ensuring the complete passage of chemical reactions with the formation of final non-toxic connections. Where, at one of the stages of the treatment process, the gas flow with the neutralized substance is accelerated at least once to supersonic speed, and then in shock waves it is transferred to the subsonic flow region, and the reaction products are rapidly cooled at a speed of 10⁶ deg/s in the range from 2000°C to 1000°C. The basis of the invention is that all physicochemical processes of toxic substance neutralization occur in a high-temperature gas flow moving at supersonic and close to sonic speeds (M>0.8). The high productivity and heat intensity of the processes in the reaction chamber, the volumetric heat release density of which is about 6000 MW/m3 and is hundreds of times higher than that of the best burner devices (with complete pre-mixing), ensures a very high completeness of physical and chemical transformations and mixing of reaction products. The temperature of the reaction products is reduced in the range from 2000 to 1000°C by rapid cooling (the cooling rate is 10⁶ deg/sec), which virtually eliminates the possibility of the formation of secondary toxic chemical compounds, especially such as dioxins and furans. At the final stage of cleaning exhaust gases from low-toxic acid-forming chemical compounds, combustion products with a low content of harmful impurities are released into the atmosphere. In terms of performance, the updated nature of the implementation of thermochemical processes in a transonic flow ensures isolation from external influences, creating expanded possibilities for regulation and control of the operating mode. These same features of transonic flow make it possible to maintain strictly discrete thermal and chemical parameters in working environments.

The development and practical implementation of the above inventions made it possible to bring the efficiency of processing (neutralization) of highly toxic substances to a qualitatively new level: the efficiency of decomposition and removal is 99.9999%; in terms of the breadth of the spectrum, covering almost all categories of especially hazardous substances, i.e. ensuring the versatility of the technology; the radically changed technical appearance of the executive means is compact, due to the high energy saturation of the workspace, which created the opportunity to create mobile executive means. The disadvantages of this method, adopted as a prototype, is the need to replace the oxidizing component - atmospheric air containing more than 75% of inert components, mainly nitrogen, with an oxidizing agent with a high oxygen content - specifically, technical oxygen of any grade.

The technical objective of the invention is to: expand the range of application of thermochemical processing in a transonic flow of sludge (multi-component, multi-fraction) waste with increasing processing efficiency in a significantly expanded range of initial raw material indicators (ash content, moisture content, calorie content, etc.), while reducing material and financial costs and improving the operating conditions of executive means.

This goal is achieved by the fact that in the method of thermochemical treatment of sludge waste in a transonic flow, a high-temperature high-speed working flow is first generated, with a temperature in the range from 300°C to 3500°C, which is mixed with the substance to be neutralized, then the mixture is accelerated to transonic speed in a gas-dynamic path and slow down the flow in the shock wave system and cool, while the process is carried out sequentially in three parallel channels, divided into temperature ranges of transonic flows with speeds of 1000 m/sec, where the first working flow with a temperature of 1600 ° C is generated by burning kerosene in compressed atmospheric air, into which the processed sludge waste is introduced and in a shock wave system at a temperature of 280°C, a vapor-gas mixture of low-boiling hydrocarbons is processed in the reaction chamber, the second working flow with a temperature of 2600°C is generated by burning kerosene in an aqueous solution of ammonium nitrate and introduced into In it, the reaction products of the first stage, purified from low-boiling hydrocarbons and at a temperature of 1500°C, process a liquid mixture of aqueous solutions and hydrocarbon components in a separation chamber of chemically active and passive substances, the third working stream with a temperature of 3500°C, formed as a result of burning kerosene in technical oxygen for processing of the solid dispersed fraction of inorganic components is cooled in a shock wave system to 2715°C, reaching the highest melting temperature of metals in the separation chamber of chemically passive substances.

It is preferable that, in accordance with a stepwise controlled temperature regime, the pressure level in the chambers is sequentially changed, observing the requirements for ensuring a critical pressure drop that ensures a transition through the speed of sound in each chamber, allowing the formation of a transonic flow region and an adjacent stagnation region in the system of bridge-shaped shock waves.

It is preferable that the selection of working power components of the basic sources of the working flow is ensured by the selection of various working media: atmospheric air, an aqueous solution of ammonium nitrate, industrial oxygen.

It is preferable that the chamber for separating chemically active and passive substances and the chamber for separating chemically passive substances have lines for introducing the liquid and solid fractions of the reaction products of the first stage, the solid fraction of the second stage, respectively, and lines for removing the reacted substances.

The inventive method for treating sludge waste in a transonic flow differs from the prototype in that the technological process of processing in a transonic flow is carried out in parallel working paths for fragments separated from the processed sludge waste that differ significantly in properties: vapor-gas mixtures representing vapors of low-boiling alcohols, ethers, aldehydes , phenols, ketones; liquid components representing hydrocarbon components and water; dispersed solid fractions, creating downstream for each component the appropriate thermochemical processing regime. Using the specific properties (autonomy, isolation, adjustability of work processes) of transonic flow in a multi-stage technological process, a strictly discrete thermochemical regime is ensured for each component extracted from raw materials. This is ensured by the use of heterogeneous sources of transonic generator gas, acceptable for each of the separated fractions: The vapor-gas mixture does not require a high oxygen potential of the oxidizing component, in particular, the use of atmospheric air is sufficient, providing a temperature level from 75°C to 300°C; Depending on the ratio of the oxygen released in the liquid phase, the oxygen potential of the supply system can also be rationally selected, for example, from aqueous solutions of ammonium nitrate or atmospheric air, providing a temperature level from 300°C to 1500°C; Treatment of dispersed solids will require high temperatures sufficient for post-processing, providing temperatures ranging from 1500°C to 3000°C. In this case, the most suitable oxidizing agent is technical oxygen, but its amount is required to process only a small fraction of dispersed solid components, constituting a few percent of the total mass of processed sludge waste.

In each of the parallel working paths for processing steam gas, liquid and solid particles, all the advantages of processing in a transonic flow, previously mastered and described in the prototype, are realized, that is, extreme mechanical, thermal and chemical effects.

Thus, the choice of optimal temperature conditions will significantly reduce the costs of forming a high-temperature transonic flow without reducing the efficiency of the process.

In accordance with the specifics of multifractional multicomponent sludge waste, each of the proposed parallel technological paths has specific features: to process the vapor-gas fraction, a low-temperature transonic gas generator is used in which the use of atmospheric air as an oxidizer is sufficient. The most functionally rich is the technological path for processing liquid fractions (water and hydrocarbon compounds), in which the neutralization of toxic inclusions, thermochemical transformations of hydrocarbon compounds with water vapor, etc. are simultaneously carried out. In addition, the specificity of the high-temperature technological path is to minimize the costs of organizing a high-temperature zone, because the amount of processed material is reduced multiple times compared to the initial amount of processed raw materials, the thermal process begins at a temperature already brought to 1500°C, and in the process of thermochemical processing the proportion of refractory components is successively reduced in accordance with the content of refractory components.

In accordance with the stepwise nature of the temperature increase, the pressure level in sections is successively reduced in compliance with the necessary requirement - ensuring a critical pressure drop that ensures the transition through the speed of sound in each section; The main requirement for the level of excess pressure in the working compartment is provided by the appropriate power system. This can be a supply tank with a pressurization system or a supply manifold under operating pressure. To implement a transonic flow, it is necessary to ensure a critical pressure difference, which for typical working media (gaseous oxygen or air) is 1.7-1.89. If the actuator system is multi-sectional, it is enough to ensure the initial pressure level in the power system, for example, 10 atm. In the first section, the pressure in the gas-dynamic path will be 10/1.89=5.29 atm; in the second section 5.29/1.89=2.8 atm; in the third section 2.8/1.89=1.48 atm. The supply pressure level of the introduced working components downstream corresponds to the level in the supercritical zone. In the intermediate sections of the transonic flow, the device for supplying working components is located in the supersonic flow zone. In particular, the range of supersonic speeds recommended in the prototype, up to the Mach number M=2, provides a reduced level of pressure (vacuum), which ensures the ejection of additionally introduced components. The removal of extracted substances behind a system of bridge-shaped shock waves with increased pressure, in any zone of the entire complex of working paths, provides a pressure difference for the full implementation of the technological process. The required pressure level of the power supply system, which is on the order of tens of atmospheres, can be practically easily achieved by a pumping system, a pressurization system or an ejection system. Such a three-section gas-dynamic path provides reliable exhaust into the environment with high environmental purity.

The intermediate sections have a line for introducing additional working components to allow the introduction into the working path of components that neutralize possible toxic substances contained in the substance being processed, as well as a line for removing reacted substances for the timely removal of non-toxic reaction products and/or useful resulting products.

The totality of advantages of processing sludge waste in a transonic flow significantly expands the possibilities, increasing the level of moisture content of the processed raw materials - up to 75%, ash content - up to 85%, and the restriction on methane number has been removed.

The technical appearance and energy intensity of actuators based on transonic combustion make it possible to create mobile complexes for waste disposal at the place of their generation.

The essence of the invention is illustrated by the drawing (Fig. 1.) which shows a block diagram of the process of processing sludge waste with three sources of working flow, representing parallel located similar high-temperature transonic gas generators - 1a, - 1b, - 1c, having a geometric means - 2 changes in flow speed, located at the exit from gas generators - 1a, - 1b, - 1c; reaction chamber - 3, having a means - 2 for changing the flow rate, located at the outlet and structurally forming part of the reaction chamber - 3; chamber for separating chemically active and passive substances - 4; separation chamber for chemically passive (solid) substances - 5; gas exhaust system - 6; oxidizer input system - 7; fuel component input system - 8; system for introducing the processed substance - 9 into the reaction chamber - 3, if necessary, including a dehydration system in the form of rough membrane cleaning to achieve a moisture content level of 75%; system for introducing special additives - 10, including a system for preparing aqueous solutions-neutralizers, in the form of containers with a stirrer and a pump supply system; system for removing the resulting components - 11 into the gas exhaust system - 6; storage tank for collecting ash residue - 12 for further processing.

The method of thermochemical treatment of sludge waste is implemented as follows: the source of the working flow is a set of three parallel transonic gas generators - 1a, - 1b and - 1c. As an oxidizing agent - 7, they use various substances containing oxygen, for example, technical oxygen, ammonium nitrate, hydrogen peroxide, atmospheric air, etc. For the source of the working flow of the gas generator - 1a, atmospheric air is used as an oxidizing component - 7, for the source of the working gas generator flow - 1b, an aqueous solution of ammonium nitrate or atmospheric air is used as an oxidizing component - 7, and technical oxygen is used for the source of the working flow of the gas generator - 1c. A wide range of hydrocarbon fuels are used as fuel (fuel) - 8, in particular kerosene, diesel fuel, methanol, ethanol, natural gas and others;

The executive system operates as follows: the working flow is accelerated in the gas generator nozzle - 1a to transonic speeds - 2 (1000 m/sec) and directed into the reaction chamber - 3, into which, through system - 9, according to a certain time law, the processed product is introduced, dehydrated to a level of 75%. substance. Depending on the specific chemical composition of the mixture, additional chemical additives are introduced into the reaction chamber - 3 through the supply system - 10, to neutralize acid gases (CO, SO ₂ , H ₂ S, NO _x ), in an amount that ensures complete neutralization processes with the formation of stable substances that do not enter into side reactions when cooled.

In the reaction chamber - 3, the gas flow with the substance to be neutralized and additives is accelerated to transonic speed - 2, as a result of geometric, consumption, thermal and chemical effects with appropriate control of heat and mass transfer processes, chemical reactions take place, in the gas flow accelerated to high speeds the substance to be neutralized in jumps seals are destroyed down to the size of molecules and active radicals, implementing the mechanics of kinetic combustion with the formation of final non-toxic reaction products. To eliminate the possibility of the formation of secondary toxic chemical compounds, the reaction products from reaction chamber 3 are quickly cooled (frozen) to temperatures below 300°C. At the exit from the reaction chamber - 3, through the system - 11 for removing the resulting components, the reacted reaction products of the vapor-gas mixture are removed to the exhaust system - 6, and the liquid and solid fractions are sent to the chamber - 4 for separating chemically active and passive substances. In the chamber there are 4 separations of chemically active and passive substances, the resulting flow is mixed with the incoming working gas generated by the gas generator - 1b, which ensures a temperature level not exceeding the boiling point from 300°C to 1500°C. In chamber - 4, the gas flow with reaction products is also accelerated - 2 to transonic speed and in shock waves is transferred to the subsonic flow region. As a result, in chamber 4 at elevated temperatures, the liquid phase is burned and separated from the solid phase. Non-toxic reaction products are sent to the exhaust system - 6, and solid (inorganic) waste is discharged into chamber - 5 for processing chemically passive (solid) substances in the form of oxides (SiO ₂ , Fe ₂ O ₃ , Al ₂ O ₃ , CaO, MgO and etc.). In chamber - 5, the solid fraction is mixed with the incoming working flow generated by gas generator - 1c. In chamber - 5, the gas flow with incoming solid waste is accelerated - 2 to transonic speed and in shock waves is transferred to the subsonic flow region, where unreacted impurities are burned out at temperatures from 1500°C to 3000°C and metals are separated from oxides (SiO ₂ , Fe ₂ O ₃ , Al ₂ O ₃ , CaO, MgO, etc.). The process in chamber 5 can largely repeat the technological process of stepwise heat treatment, up to the melting level of refractory oxides above 3000°C.

Example 1: consider the actual composition of industrial sludge waste treatment with the following main indicators without taking into account moisture content: organic part 50% (carbon - 63.5%, hydrogen - 7%, sulfur - 0.5%, nitrogen - 5%, oxygen - 24 %) and mineral part 50% (SiO ₂ - 44%, Al ₂ O ₃ - 15%, Fe ₂ O ₃ - 15%, CaO - 12%, MgO - 12%, and others - 2%). Depending on conditions, storage time and other factors, actual moisture content can vary within an extremely wide range - from 30% to 98%). When using this method, preliminary preparation of sludge to a dry state is irrational. From the point of view of transonic combustion efficiency, moisture content up to a level of 75% is favorable. The associated costs for dehydration of processed raw materials from 98% to 75% can be minimal compared to the practiced dehydration to a dry residue or to the level of 30% required for waste neutralization in traditional thermochemical processes. When choosing a rational level of moisture content in the processed raw material for processing in a transonic flow, the initial moisture content in the working supersonic flow formed as a result of the combustion of fuel components, in turn containing a high level of water, is taken into account (for example, when using an aqueous solution of ammonium nitrate containing 25 % water preliminarily prepares sludge waste to a level of 50% moisture content), and the thermochemical calculation method makes it possible to determine with high accuracy the total level of moisture content of the material being processed and the working component.

As a result of processing sludge waste in a transonic flow, non-toxic gaseous reaction products and ash residue are formed, suitable for further processing, or its use as a raw material for construction materials, etc.

Example 2.

As an example, we took a real sample of sludge waste from MSUE Saratovvodokanal (Tables 1 and 2) with a moisture content of 50%, an organic part of about 30% and an inorganic part of about 20%.

Based on the completed project and estimated thermodynamic calculations, the treatment of sludge waste in a transonic flow of the presented components is shown in the example of Table 1.

To implement the first stage of separating low-boiling hydrocarbons, a high-temperature, high-speed working flow (working gas) is generated by burning kerosene in compressed atmospheric air (for economic reasons, it is advisable to use atmospheric air as an oxidizer). To burn 20 kg of kerosene, 400 kg of compressed atmospheric air is required, with the value of the stoichiometric coefficient of excess oxidizer α = 1.1, complete combustion of kerosene and a working gas temperature of 1600°C are ensured. When the ratio of the working gas of the combustion products of kerosene (hydrocarbon) in atmospheric air with sludge waste is 1:1, as well as providing an initial pressure level of 10 atm, a reaction temperature level at the first stage of 280°C is ensured, which makes it possible to achieve the boiling point of almost all low-boiling hydrocarbons components.

At the second stage, in the reaction zone for processing heavy hydrocarbons, water and aqueous solutions, a high-temperature high-speed working flow (working gas) with a temperature of 2600°C is generated by burning kerosene in an aqueous solution of ammonium nitrate (60% ammonium nitrate, 40% water ), with a pressure of 5.29 atm, in an amount of 0.3-0.4 relative to the mass of the hydrocarbon fraction, providing a temperature of 1500°C when injecting reaction products of the first stage of sludge waste treatment. A temperature of 1500°C in the reaction zone guarantees highly efficient complete combustion of the hydrocarbon components of sludge waste.

After processing the organic hydrocarbon fraction, water and aqueous solutions of sludge waste, less than 20% of solid sludge waste remains. If it is expedient to isolate valuable metals (in particular Ni, Cr and ZrO ₂ ) in a total amount of about 0.5% of the total volume of the ash part. To achieve the melting temperature ( _Tm Ni - 1455°C, Cr - 1907°C, ZrO2 - 2715°C - Table 1), it will be necessary to heat the bottom ash to a level of 2715°C; this requires the introduction of a small amount of technical oxygen (16 kg) into reaction zone. To do this, by burning kerosene in technical oxygen, a high-temperature high-speed working stream (working gas) with a temperature of 3500°C is generated, into which the remainder of the solid sludge waste (second-stage reaction products) is introduced, which ensures the reaction temperature at a temperature of 2715°C, for isolation of valuable metals Ni, Cr and ZrO ₂ .

The technical result from the use of the proposed invention allows: to expand the scope of application of transonic combustion for the treatment of multifractional multicomponent waste; reduce the volume of waste generated or accumulated as a result of the operation of treatment facilities; significantly simplify the neutralization process by simplifying the preparatory stages for dewatering sludge waste; reduce the costs of organizing the waste management process

Claims (4)

1. A method for thermochemical treatment of sludge waste in a transonic flow, according to which a high-temperature, high-speed working flow is first generated, with a temperature in the range from 300 to 3500°C, which is mixed with the substance to be neutralized, then the mixture is accelerated to transonic speed in a gas-dynamic path and slowed down flow in a shock wave system and cooled, characterized in that the process is carried out sequentially in three parallel channels, divided into temperature ranges of transonic flows with speeds of 1000 m/s, where the first working flow with a temperature of 1600°C is generated by burning kerosene in a compressed atmospheric air into which the processed sludge waste is introduced, and in a shock wave system at a temperature of 280°C, a vapor-gas mixture of low-boiling hydrocarbons is processed in the reaction chamber, the second working flow with a temperature of 2600°C is generated by burning kerosene in an aqueous solution of ammonium nitrate and introduced into it The reaction products of the first stage, purified from low-boiling hydrocarbons and at a temperature of 1500°C, process a liquid mixture of aqueous solutions and hydrocarbon components in a separation chamber for chemically active and passive substances, the third working stream with a temperature of 3500°C, formed by burning kerosene in technical oxygen for processing solid dispersed fraction of inorganic components is cooled in a shock wave system to 2715°C, reaching the melting temperature of metals in the separation chamber of chemically passive substances. 2. The method according to claim 1, characterized in that, in accordance with a stepwise controlled temperature regime, the pressure level in the chambers is sequentially changed, observing the requirements for ensuring a critical pressure drop that ensures a transition through the speed of sound in each chamber, allowing the formation of a transonic flow region and an adjacent region braking in the system of bridge-shaped shock waves. 3. The method according to claim 2, characterized in that the selection of working power components of the basic sources of the working flow is ensured by the selection of various working media: atmospheric air, an aqueous solution of ammonium nitrate, industrial oxygen. 4. The method according to claim 3, characterized in that the chamber for separating chemically active and passive substances and the chamber for separating chemically passive substances have an input line for the liquid and solid fractions of the reaction products of the first stage, a solid fraction of the second stage, respectively, and a line for the removal of reacted substances.

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