RU2544949C1 - Processing method of domestic and industrial solid wastes - Google Patents

Abstract

FIELD: power industry.

SUBSTANCE: method involves their preliminary processing, loading to a reactor, heating, drying, high-temperature pyrolysis and combustion of pyrolysis gas with formation of products after processing in gaseous and liquid phases, removal of products after processing from the reactor, startup of the reactor, zones of low-temperature and high-temperature pyrolysis is performed by start-up fuel by means of combustion chambers located in the upper part of the reactor and in the lower part of the reactor housing. Products after processing of startup fuel from zones of low-temperature and high-temperature pyrolysis are sent for heating of a steam boiler through ejectors of its combustion chambers. When in a working mode, the obtained pyrolysis gas is supplied through reactor headers to the ejector of the combustion chamber of the steam boiler, where its complete combustion is performed, and at the same time, combustion products of the main fuel of the reactor are supplied through the ejector of the other combustion chamber.

EFFECT: improving efficiency of a processing process, an efficiency factor of the whole cycle at simultaneous environmental safety of the processing process.

3 dwg

Description

The invention relates to the field of waste disposal and may find application in the processing of solid household and industrial waste.

A known method of processing solid household and industrial wastes, including their preliminary processing and loading into the reactor, heating, drying, pyrolysis and burning with the formation of processed products in the gaseous and liquid phase, the withdrawal of processed products from the reactor (see UDC 620.92; B63; BBK31, 15 “Biomass as a source of energy”: Translated from English / Edited by S. Soufer, O. Zaborski - M., 1958, p. 121).

During the processing method, pyrolysis occurs, as a result of which pyrolysis gas is obtained, part of which is burned and the received heat from the combustion products is supplied through heat conduction to perform technological operations of heating, drying, pyrolysis and combustion, and the other part of the pyrolysis gas is mixed with air, obtained air-fuel the mixture is burned, and hot combustion products are supplied to perform the processing operations of the processing method.

Significant disadvantages of this method are:

- low productivity of the processing process, due to:

- low efficiency of the waste processing process, which is determined by the introduction of heated air, the temperature of which is limited to 1100 ° C, which does not ensure the intensification of the process;

- arbitrary loading of waste into the reactor, in which there are voids that reduce the volume of the processed mass of waste;

- the need to perform the operation of heating the air supplied by the source;

- low output of pyrolysis gas to an external consumer, due to the fact that its main amount is consumed to heat the air used as a gasifying agent;

- low efficiency of the cycle of the processing process, due to heat loss to the atmosphere from the regeneration columns during the operation of the process of heating the air in them, as well as heat losses during the movement of heated air through the communication systems connecting these columns with the reactor.

Closest to the claimed is a method of processing solid domestic and industrial waste, including pre-treatment and loading into the reactor, heating, drying, pyrolysis and burning with the formation of processed products in the gaseous and liquid phase, the conclusion of the processed products from the reactor, according to the invention, heating, drying , pyrolysis and combustion are carried out in a reactor at absolute pressure, 0.08-0.095 MPa, 15-30% of the pyrolysis gas is used as a process gas, and the rest of it is used as energy fuel, wherein the process pyrolysis gas is pre-mixed with air with an excess coefficient of 1.0-4.69, and the household waste is pretreated by grinding, mixing with flux and pressing, after which they are sealed packages that are loaded into the reactor through the lock chamber, while the packaging is made of a cylindrical shape from a polymer film (see IPC F23G 5/00, description of the invention to patent No. 2213908 of the Russian Federation, publ. 10/10/2003)

Significant disadvantages of this method are:

- low efficiency of the use of the obtained heat in the heating, drying and preliminary pyrolysis zone in the reactor shaft both during operation of the combustion chambers on starting fuel in the heating mode of the reactor and in the steady state when working on the main fuel (pyrolysis gas) due to the emission of combustion products having a still high temperature of at least 500 ° C through the treatment plant (the exhaust gases need to be cooled) with a smoke exhaust through a chimney into the atmosphere;

- insufficient calorific value of the resulting pyrolysis gas due to the presence of a large amount of nitrogen in it when mixed with air, providing a fuel-air mixture with a given coefficient of excess air, which is burned to produce high-temperature combustion products, including hot air, water vapor and dioxide carbon and nitrogen.

The technical result of the proposed technical solution is to increase the productivity of the processing process, the efficiency of the entire cycle while the environmental safety of processing.

The essence of the technical solution lies in the fact that in the method of processing solid household and industrial wastes, including their preliminary treatment, loading into the reactor, heating, drying, high-temperature pyrolysis and burning of pyrolysis gas with the formation of processed products in the gaseous and liquid phase, the conclusion of the processed products from reactor, reactor start-up, low-temperature and high-temperature pyrolysis zones are carried out with starting fuel, respectively, by means of combustion chambers located in the upper part of the reactor torus and in the lower part of the reactor vessel, then the starting fuel processing products from these zones are sent to heat the steam boiler through the ejectors of its combustion chambers, and in the operating mode, the pyrolysis gas obtained is fed through the reactor manifolds to the ejector of the combustion chamber of the steam boiler, where it is completely burned , and at the same time through the ejector of another combustion chamber serves the combustion products of the main fuel of the reactor.

Starting the reactor with starting fuel of a gaseous or liquid type and the direction of the processed products allows preheating of both zones and at the same time ensures heating of the steam boiler, which reduces its heating time. It allows to exclude thermal losses of the combustion process and increase the efficiency of the entire technological cycle.

The direction of the starting fuel processing products from the zones of low-temperature and high-temperature pyrolysis ensures heating of the steam boiler through the ejectors of its combustion chambers, intensifies the process and increases the productivity of the waste processing.

The pyrolysis gas obtained in the operating mode and supplied through the reactor manifolds to the ejectors of the combustion chambers of the steam boiler and simultaneously through the ejectors of other combustion chambers, the supply of the combustion products of the main fuel of the reactor allows its complete combustion, which increases the efficiency of the processing process and increases the efficiency of the entire cycle for due to the reduction of heat loss, the use of the obtained heat in the heating, drying and preliminary pyrolysis zone in the reactor shaft, we previously throw x and scattered into the atmosphere, as in the combustion chambers on the starting fuel in the reactor heating mode and steady state operation at the main fuel (pyrolysis gas), and the entire thermal energy is directed into the boiler.

The environmental safety of the waste processing process is ensured due to the fact that the process of pyrolysis gas formation occurs as a result of high-temperature pyrolysis of solid household and industrial waste at a reaction temperature T = 1650 ° C, which implies the “collapse” of all harmful substances, and the formation of dioxides is prevented by short transportation pyrolysis gas from the place of its formation to the place of combustion in the steam boiler, while the pyrolysis gas does not have time to cool to the temperature of formation of dioxides and resins.

The method is as follows (see figure 1). Recycled waste from garbage trucks (dump trucks) is unloaded into a receiving hopper 1, from where a belt conveyor 2 enters the grinding and mixing device 3 with a flux and then through a belt conveyor 4, above which a magnetic separator 5 is installed, which removes metal from the conveyor belt, sent to the site 6 pressing and packaging, where they are pressed and packaged in packaging 7 of a cylindrical shape, which is wrapped with a special mesh (not shown in the drawing) to fix the shape, and then several layers of polymer film. The sealed packages thus obtained are transferred to a conveyor 8, from which, by means of a pusher (not shown) enter a lock chamber 9, the lid 10 of which is closed, the chamber volume is sealed, and, after opening the valve 11, the working volume of the reactor 12 is sequentially filled, where produce heating, drying and pyrolysis of the processed waste at an absolute pressure of 0.08 MPa (figure 2).

A magnetic separator 5 discharges the metal into a semi-automatic press 13, where the metal is pressed into briquettes and then transported to metallurgical plants.

The ignition of the combustion chambers 14 is carried out using a starting device (not shown in the drawing). At the same time, at the exit from the combustion chambers 14, high-temperature high-speed flows of combustion products are formed, which heat up the heating, drying, and pyrolysis zone. Through the pipe 15 and through the ejector of the combustion chamber 16 of the steam boiler 17, hot combustion products enter the steam boiler 17 and are removed, giving off excess heat through the cleaning device 18, the smoke exhauster 19 and the pipe 20 to the atmosphere. Then produce ignition of the combustion chambers 21 on starting fuel (figure 3). The starting fuel is gaseous or liquid with the simultaneous supply of main air (air lines are not shown conditionally), the starting device is a glow plug. The high-temperature heat fluxes of the combustion products of the zone of high-temperature pyrolysis, moving along a helical line, wash the outer surface of the pocket 22, ensuring uniform heating of all zones of the internal volume of the reactor vessel 23, and giving most of the thermal energy to the processed products through the inner wall of the pocket 22, the combustion products by means of a pipeline 24 and through the ejector of the combustion chamber 25 of the steam boiler 17, hot combustion products are supplied to the steam boiler, which are then removed, giving off excess heat through h cleaning device 18 smoke exhauster 19 and the pipe 20 into the atmosphere.

After entering the operating mode, the supply of starting gaseous or liquid fuel to the chambers 14 and the glow plug are turned off. In the steady-state operating mode, the hot pyrolysis gas obtained as a result of the start-up of the plant enters through the ejectors of the combustion chamber 14, through the openings 26, the collector 27, and the channel 28 into the heating, drying, and pyrolysis zone (starting fuel, ejector, and main air are turned off). Moving along the channels, the gas washes the heating and drying zone, distributing the thermal energy of the flows over the entire surface. Next, the hot pyrolysis gas through the pipeline 15 and through the ejector of the combustion chamber 16 of the steam boiler 17 is used as the main fuel, burned in the steam boiler. Next, the combustion products that have given up excess heat are removed through a cleaning device 18, a smoke exhauster 19 and a pipe 20 into the atmosphere.

After entering the operating mode, the supply of starting gaseous or liquid fuel is shut off to the combustion chambers 21, in which the pyrolysis gas combustion process is carried out by supplying ejector air. When this occurs, the “suction” of hot pyrolysis gas from the collector 27, and it is used as the main fuel of the combustion chambers 21, and the steam boiler 17 is heated through the ejector of the combustion chamber 25 of the steam boiler 17, using the pipe 24. Hot combustion products, giving off excess heat, are removed through the cleaning device 18, the exhaust fan 19 and the pipe 20 into the atmosphere.

The processed waste is transferred from the drying zone to the high-temperature pyrolysis zone, where it is subjected to continuous heat treatment transmitted through the inner wall of the pocket 22 and completely gasified, and the resulting pyrolysis gas leaves the piping 26 into the collector 27, and from it through the pipe 29 into the ejectors of the combustion chambers 30, 31 of the steam boiler 17 and is burned, as the main fuel, in the steam boiler. The ejector combustion chambers are divided into the main 30, which operates in a constant mode and maintains the temperature and steam flow in the required parameters required by the consumer, and the control chamber 31, necessary to maintain thermal conditions and rarefaction in the reactor itself due to the ejector of the combustion chamber 31, changing the flow rate of the ejector air. The remaining untreated particles under the influence of high temperatures are converted into liquid slag and periodically released through the slag valve 32 into the truck 33 and taken out for further processing and use.

Superheated steam under pressure from a steam boiler 17 is fed through a pipe 34 to a turbogenerator installation 35 for generating electric energy, and the exhaust steam is fed through a pipe 36 to a separator 37, where it condenses into water, then it enters the condensate collector 38 and a circulation pump 39 through the main pipelines 40, having given the excess heat to consumers 41, is returned to the steam boiler 17. The blower (not shown) provides the necessary costs for the reactor 23 and the steam boiler 17. Gaseous products of processing and from the steam boiler 17 enter the purification device 18, which ensures the purification of the exhaust gases to the MPC and the smoke exhauster 19 is sent to the chimney 20.

The proposed method of processing solid domestic and industrial waste provides an increase in the productivity of the processing process by intensifying the process, increasing the efficiency of the entire cycle with simultaneous environmental safety.

Claims (1)

A method for processing solid household and industrial wastes, including their preliminary treatment, loading into a reactor, heating, drying, high-temperature pyrolysis and burning of pyrolysis gas with the formation of processed products in the gaseous and liquid phase, output of the processed products from the reactor, characterized in that the reactor is started, zones of low-temperature and high-temperature pyrolysis is carried out starting fuel, respectively, by means of combustion chambers located in the upper part of the reactor and in the lower part of the reaction vessel ora, then the starting fuel reprocessing products from these zones are sent to heat the steam boiler through the ejectors of its combustion chambers, and in the operating mode, the pyrolysis gas obtained is fed through the reactor manifolds to the ejectors of the combustion chambers of the steam boiler, where it is completely burned, and simultaneously through ejectors of other The combustion chambers supply the combustion products of the main fuel of the reactor.

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