EA002262B1 - Process for incineration of organic waste products and an installation therefor - Google Patents

Abstract

1. A process for incineration of organic waste products comprising charging wastes in an incineration drum and simultaneous recycling calcined solid heat carrier (ash), forced protruding through and heating the obtained mixture with evaporating of water and burning organic matter in a stream of heated air forming solid and gaseous heat carriers, discharging and cleaning burning products, characterized in that a temperature of the mixture is maintained between 100 and 120 degree C in the loading zone under constant control, and formed water vapor is transferred to the zone of hot ash unloading, further air, heated to at least 200 degree C, is fed through the whole length of the burning zone with raw material being intensively mixed above the raw layer, after burning the organic matter the burning products are transferred to an afterburning zone using the heat produced for an additional heating of raw materials in the loading and burning zones, and then gradually cooling them with an air of a variable temperature which is fed through the whole length of the afterburning zone. 2. The process according to claim 1, characterized in that in case of a deficit amount of the produced ash, minerals, such as sand crushed limestone etc, are added to a raw material prior to loading to form a solid heat carrier totally amounting to at least 20% of summed mass of wastes being loaded. 3. The process according to claim 1, characterized in that the air for waste burning is heated in the drum heat-insulating system, the required degree of heating is reached by repeated blowing of excess air through said system. 4. An installation for incineration of organic waste comprising a rotating horizontal drum consisting of two concentrically positioned outer and central pipes rigidly connected by longitudinal strips forming inter-sector space, blades for counter movement of wastes and calcined solid heat carrier in their cavities, spiral duct with an adjustable input opening connected with an inter-pipe space and an output opening to the loading zone, brick lining of the outer pipe in the shape of a heat-insulated shell ring, loading/unloading and burning chambers, means for waste loading and ash removal, means for feeding blow air, purification and discharge of flue gases, characterized in that a number of openings are made on the both ends of the outer pipe, closed from outside with supplying and discharging air collectors made in said loading/unloading and burning chambers and connected with a brick-lined outer cavity, formed by the outer pipe an intermediate concentrically-positioned shell ring with spiral ducts of counter movement on both surfaces, wherein tubular ducts are made from the brick-lined outer cavity to each sector of the inter-pipe space at the outlet of it, and tubular pipes are made from the brick-lined inner cavity for the rest of length of the inter-pipe space and above the bottom of the central pipe through the length of the burning chamber, a discharge pipe with an adjustable gate is made from the zone of the central pipe loading to the zone of ash removal and purifying of flue gases of the loading/unloading chamber. 5. The installation according to claim 4, characterized in that a screen is provided at the entrance of the burning zone in the central pipe enabling to move raw material. 6. The installation according to claim 4, characterized in that there must be at least two spiral ducts from inter-pipe space to the loading zone of the central pipe, evenly-spaced over the central pipe circumference, wherein a threshold is positioned directly after the adjustable input opening in the inter-pipe space for concentration of calcined solid heat carrier. 7. The installation according to claims 4, 5 and 6, characterized in that an inclination angle of the drum longitudinal axis to the horizon can reach 30 degree to each side.

Description

The invention relates to the processing of any waste containing organic compounds, including oil-containing raw materials with a low concentration of hydrocarbons, organic waste paint and varnish production, domestic infected waste in order to solve economic problems of cleaning industrial pollution of the environment.

A known method of cleaning and reclamation of oil-contaminated territories with biological products containing oil-oxidizing microorganisms, for example Olevorin (certificate of the Sanitary Inspection of the Russian Federation No. 008148).

The disadvantage of this method is low efficiency and even complete stop of the cleaning process at ambient temperatures below + 5 ° C and above + 37 ° C, as well as in the absence of a sufficient amount of moisture and plant layer.

A known method of cleaning contaminated soil from petroleum products and a device for its implementation (RF patent No. 2027825, class E 02B 15/04, A 01C 21/00, 1995) by washing with hot water at a temperature of 70-90 ° C while stirring with a stirrer in bunker.

The disadvantages of the invention are the significant duration and lack of effectiveness of the oil washing process, the large removal of oil-contaminated water with under-treated soil, leading to additional environmental pollution, the inability to use the method to eliminate other types of organic waste.

A device for thermal disposal of wet waste in a rotary kiln (AS USSR No. 1291791, class E 236 5/20, EV 7/28, 1987), including the loading of raw materials in an inclined rotary kiln, its promotion due to the inclination of the kiln, heating the burner with the counterflow of flue gases and the heat transfer of the heated walls of the inner shell, heating the air in the lining cavities, burning waste in the counterflow of heated air, burning the flue gases in a vortex afterburner and removing combustion products.

The disadvantages of the device are the low efficiency of processing waste, which is prone to sticking together due to the formation of large lumps of raw materials and its adhesion to the surface of the furnace, the large length of the furnace to ensure complete combustion of the waste, part of the unburned gases entering the atmosphere through the loading device, and the inefficient furnace device due to poor mixing of waste and the upper supply of blast air, excessive heat consumption for heating the generated water vapor in the furnace, and the inability to use the device in a mobile x units operating on by unplanned terrain.

The closest in technical essence to the proposed method and device is a method for the extraction of hydrocarbons from oil-containing raw materials and a device for its implementation (RF patent No. 2078112, class С10В 1/10, 53/06, 1994), which includes loading the raw materials into the horizontal inner tube reactor with simultaneous supply to the loading zone of the calcined solid coolant, further forced promotion and heating of raw materials, evaporation of water and the organic part, their removal and burning of coke in the annular annular space with Scientists need for process heat.

A disadvantage of the known solution lies in the fact that the heat costs of ensuring the processing of raw materials are compensated by burning the resulting coke and gas only if the content of organic matter in the raw material is more than 6%. Weakly greased soils with a lower oil content require an additional supply of thermal energy for processing, which makes the process economically disadvantageous and inefficient. In addition, the adopted axial method of supplying blast air lowers the temperature in the furnace and does not provide complete combustion of coke, and the air itself is poorly heated before being fed into the combustion zone.

The objective of the invention is to develop a method and apparatus for eliminating organic waste by heat treatment with forced movement in the combustion and afterburning zones.

The technical result achieved by the implementation of the invention is to increase efficiency by improving quality, reducing cost and making it possible to process a variety of organic waste.

To achieve the technical result indicated in the method of eliminating organic waste, including loading the raw materials into the furnace with simultaneous recirculation of the calcined solid heat carrier (ash) into it, forced promotion and heating of the mixture with evaporation of water and burning of organic matter in a stream of heated air with the formation of solid and gaseous heat carriers, removal and purification of combustion products, in the loading zone, with constant monitoring, by supplying the calcined solid coolant support The mixture temperature is 100-1 20 ° С, and the formed water vapor is transferred to the hot ash discharge zone, then along the entire length of the combustion zone with vigorous stirring of the raw material, air heated to a temperature of at least 200 ° С is fed directly above the raw material layer, after burning the main part of the organic substances, the combustion products are transferred to the afterburning zone using the heat obtained for additional heating of the central pipe and then they are gradually cooled by the variable temperature air supplied along the entire length of the afterburning zone. In case of insufficient amount of ash obtained in the raw material, a mineral part, for example, sand, crushed limestone, etc., is introduced on a return basis before loading. to obtain the total solid coolant with ash in an amount of at least 20% by weight of the loaded waste. The waste incineration air is heated in the thermal insulation system of the furnace, while the required degree of heating is achieved by repeatedly blowing excess air through this system.

To achieve the specified technical result in a device for the elimination of organic waste, containing a rotary horizontal furnace, consisting of two concentrically arranged outer and central pipes, rigidly interconnected by longitudinal ribs with the formation of a sector annular space, vanes for the onward movement of waste and annealed solid coolant in them cavities, a spiral channel with an adjustable inlet connected to the annulus and an outlet inward three loading zones, lining of the outer pipe in the form of a shell with heat insulating material, loading and unloading and burner chambers, means for loading waste and evacuating ash, devices for supplying blast air, cleaning and removing flue gases, a number of holes are made at both ends of the outer pipe, closed on the outside by inlet and outlet air collectors made in the bodies of the loading and unloading and burner chambers and connected to the outer lining cavity formed by the outer pipe and the intermediate con centered shell with spiral channels of the opposite direction on both surfaces, while from the outer cavity of the lining tubular channels are made to each sector of the annular space at the exit from it, and tubular channels are made from the inner cavity of the lining to the remaining length of the annular space and above the bottom of the central pipe the length of the combustion zone, while from the loading zone of the central pipe a bypass pipe with an adjustable gate valve into the zone of ash discharge and flue gas cleaning unloading chamber. At the beginning of the combustion zone in the central pipe, a screen is made with the possibility of promoting raw materials. There should be at least two spiral channels from the annular space into the loading zone of the central pipe with a uniform distribution around the circumference of the central pipe, while a threshold for the concentration of the calcined solid coolant is placed directly behind the adjustable inlet in the annular space. The angle of inclination of the longitudinal axis of the furnace relative to the horizon can reach 30 ° in each direction.

Incineration of waste in an oven with an additional central tube and blades for the promotion of raw materials and burning waste with the supply of heated air in the furnace to the combustion and afterburning zones and sprinkling of the loading zone with calcined ash improves the quality of cleaning, reduces the size and cost of the furnace, allows you to eliminate any waste containing organic matter, those. makes it more efficient.

Example 1

In a rotary kiln of a pilot plant with a capacity of up to 100 kg / h, oil-contaminated soil was collected at the site of the violation of the integrity of the valve gate in the Perm District Oil Pipeline Department, with an organic content of 8.7 wt. % The total amount of processed raw materials in the experiment was 127 kg.

The furnace is preheated with a burner and the diesel fuel burned in it to a temperature in the combustion chamber of 300 ° C. Then the loading device to the furnace inlet continuously serves prepared raw materials.

At the beginning of the loading zone, burnt solid coolant in the amount of 13 kg is evenly poured onto the cone bed, and raw materials are poured on top, which quickly warms up to a temperature of 100-120 ° C and water is evaporated from it. Water vapor is sucked off and fed to the flue gas treatment cyclone.

Moving further with the help of the blades into the central pipe, the raw material passes by the screen and enters the combustion zone heated from the nozzle of the burner device. In this case, the hydrocarbon fractions are evaporated, the vapors flare up and, mixed with the supplied hot air, burn. The combustion process continues throughout the central pipe. Then the burnt raw material is poured out of it and enters the annular annular space with the access of oxygen, where it burns out when moving the blades along the longitudinal sector channels of this space in the opposite direction, heating the central tube of the furnace.

The burnt clean mineral part at the beginning of the furnace is cooled with air, poured out and removed outside the furnace.

Example 2

In a rotary kiln of a pilot plant with a capacity of up to 100 kg / h, organic waste from the dyeing production of the carpet mill was processed, including small tow of wool, dye waste and parts of wood and cardboard containers. The total amount of processed raw materials in the experiment was 34 kg.

The furnace is preheated with a burner and diesel burned in it to a temperature in the combustion chamber

300 ° C. Then the loading device to the furnace inlet continuously serves prepared raw materials.

At the beginning of the loading zone, burnt solid coolant in the amount of 13 kg is evenly poured onto the cone bed, and raw materials are poured on top, which quickly warms up to a temperature of 100-120 ° C and water is evaporated from it. Water vapor is sucked off and fed to the flue gas treatment cyclone.

Moving further with the help of the blades into the central pipe, the raw material passes by the screen and enters the zone of the torch from the nozzle of the burner device. In this case, the hydrocarbon fractions are evaporated, the vapors flare up and, mixed with the supplied hot air, burn. The combustion process continues throughout the central pipe. Then the burnt raw material is poured out of it and enters the annular annular space with the access of oxygen, where it burns out when moving the blades along the longitudinal sector channels of this space in the opposite direction, heating the central tube of the furnace.

The burnt clean mineral part at the beginning of the furnace is cooled with air, poured out and removed outside the furnace.

Example 3

In a rotary kiln of a pilot plant with a capacity of up to 100 kg / h, domestic infected waste was processed, including food waste, paper, napkins, etc., delivered from the side of an airliner that flied from Pakistan during an outbreak of cholera. Waste prior to delivery was briquetted and packed in cardboard containers.

The furnace is preheated with a burner and the diesel fuel burned in it to a temperature in the combustion chamber of 200-250 ° C. Then, with the preservation of safety measures, briquettes of infected waste are conveyed to the inlet of the furnace. Together with the waste, packing material and sand are additionally loaded in an amount of 6 kg.

At the beginning of the loading zone, burnt ash with hot sand is evenly poured onto the conical bed, and raw materials are fed from above, which quickly warms up to a temperature of 100-120 ° C and water is evaporated from it. Water vapor is sucked off and fed to the flue gas treatment cyclone.

Moving further with the help of blades into the central pipe past the screen, the raw material enters the heating zone from the burner when hot air is supplied there. In this case, heating and ignition of the raw material occurs. The combustion process continues along the entire length of the central pipe, and due to rotation and hitting the blades, the briquettes are destroyed and the waste burns out more intensively. The afterburning of unburned particles occurs after the burnt mass enters the annular annular space with the access of atmospheric oxygen.

The ash mixed with the sand supplied to the furnace is cooled at the beginning of the furnace with air, poured out and removed outside the furnace.

From the obtained calcined mineral part and ash, samples are taken and the completeness of purification of organic waste is determined.

In FIG. 1 schematically shows a longitudinal section of the described device, FIG. 2 view A of FIG. 1, in FIG. 3 is a section BB in FIG. one.

The device for eliminating organic waste contains a horizontal rotary kiln 1, consisting of two concentrically located outer 2 and central 3 pipes, rigidly interconnected by longitudinal ribs 4 with the formation of a sector annular space 5. The furnace 1 by means of two bandages 6 attached to the outer pipe 2, It is supported by support roller carts 7 and rotates from the drive 8. From the front end of the furnace there is a loading and unloading chamber 9 with an exhaust air collector 10, a loading chute 11, and a cycle Onami 12 flue gas cleaning. From the rear end of the furnace there is a burner chamber 13 with a burner 14, an inlet air collector 15, an outlet air channel 16 with a pipe 17, lined with refractory material 18. A blower 19 is connected to the inlet air collector 15, the inlet of which is connected to the outlet manifold 10 through the valve 20 , with the possibility of air intake.

In the central pipe 3, not far from the inlet 21, a protective shield 22 is placed. On the inner surface of the pipe 3, blades 23 are installed, forming screw surfaces for moving the raw materials. The blades 23 have a L-shaped profile for better tedding of heated and burning particles. On the outer surface of the central pipe 3, longitudinal ribs 4 are fixed, on each of which blades 24 are installed at an angle to the longitudinal axis of the furnace 1. The angle or pitch of the blades 24 can be variable along the length of the ribs 4.

The longitudinal ribs 4, in turn, are fastened with a shell 25 rigidly connected to the outer pipe 2. In the annular space 5 between the outer pipe 2 and the shell 25 there is an intermediate shell 26 having spiral ribs 27 of the opposite direction on both surfaces. The device of the shells 25 and 26 is designed so that they form consecutive channels for the passage and heating of air from the inlet 15 to the exhaust manifold 10 and the air channel 16 with the pipe 17. In the end part of the intermediate shell 26 near the loading 002262 discharge chamber, tubular channels 28 are installed in each annulus sector 5. Similar channels 29 to sectors on the remaining annulus 5 are made of shell 25.

After the cyclones 12, a chimney 30 with a shutter 31 is installed on the loading and unloading chamber 9. A chimney 32 with a shutter 33 coaxially inserted into the chimney 30 is connected to the exhaust air collector 10. From the loading zone 34 of the central pipe 3, a 35 s pipe is connected to the cyclone 12 damper 36.

The device operates as follows. First, the furnace 1 is heated by the burner 14 to a temperature of 200-300 ° C in the combustion chamber. To do this, gas or liquid fuel is supplied to the burner 14, the blower 19 is turned on, air is supplied to the combustion zone 37, and the combustible mixture is ignited. After that, the drive 8 rotates the furnace 1.

Without stopping the supply of fuel to the burner 14 and air, raw materials, for example, contaminated soil, are loaded onto the conveyor 38 and fed through the loading chute 11 into the loading zone 34 of the central pipe 3.

At the same time, closer to the front end of the loading zone 34, a hot annealed mineral part is poured from the outlet 39 of the spiral channel 40, which is supplied from the annulus 5 and enters the conical surface 41 of the loading zone 34. The raw materials entering the conical surface 41 are mixed with rotation hot annealed mineral part, moves along a slope towards the protective screen 22.

During the advance, when heating above 100 ° C, moisture evaporates from the raw materials, the vapors are sucked out through the pipe 35, they enter the cyclone 12 for irrigation of flue gases and are emitted with them into the atmosphere.

After the slope 41, the raw material is moved by the blades 23 past the protective shield 22, into the combustion zone 42 of the central pipe 3. Here, hydrocarbons evaporate from the raw materials under the influence of thermal energy, which ignite and burn when heated air is supplied through the pipe 17. The process contributes to the constant tedding of raw materials during rotation of the furnace 1. With a stable combustion process, the burner 14 is turned off.

Burnt raw material is poured from the central pipe 3 into the annulus 5 and, using blades 24, moves towards the loading and unloading chamber 9. During this movement, unburned particles and carbon oxides are burned.

The waste combustion air is supplied by the blower 19 to the inlet air collector 15, then it enters the upper spiral channels 43 of the annular space between the outer pipe 2 and the intermediate shell 26, cooling the outer pipe 2, then passes through the lower spiral channels 44 between the shells 25 and 26, heats up and, passing the exhaust air channel 16, through the pipe 17 enters the combustion zone 42 of the central pipe 3. A portion of the heated air from the lower spiral channels 44 through the tubular channels 29 enters the burner chamber 13 and the inter ubnogo space 5 in the afterburning. Part of the cold air from the upper spiral channels 43 through the tubular channels 28 is fed to the output of the annular annular space 5 for cooling ash and flue gases.

Air from the exhaust air manifold 10 through the valve 33 and the pipe 32 is supplied, if necessary, to the chimney 30 to create draft.

After heating the mineral part or ash and flue gases after heating the central pipe 3 at the outlet of the annular annular space 5, they enter the cyclones 12 of the loading and unloading chamber 9. The flue gases, after being cleaned, are released into the atmosphere, and the ash is discharged from the device through a conveyor 45.

The device is equipped with a sensor system for monitoring and controlling the process.

To carry out adjustments and repairs in the chambers 9 and 13 and on the outer pipe 2, quick-detachable hatches (not shown) are provided.

The application of the proposed method and device allows to eliminate the buildup of raw materials in the furnace, increase productivity and reduce the installation length by 25-40% by reducing the heating cycle of the waste due to the recirculation of the annealed mineral part or ash from the annulus to the feed zone of the feed and removal of water vapor generated, and also additional heating of the central pipe along with the solid and gaseous coolant loaded with raw materials.

By heating the air in the heat insulation system of the furnace, the costs of manufacturing and operating the installation are reduced, heated air is supplied directly to the combustion and afterburning zones, the use of smoke exhausters in the flue gas exhaust system is excluded, and the sealing of the combustion zones of a rotary kiln is simplified.

The use of a protective screen eliminates the heating and ignition of raw materials at the time of their loading into the furnace, increases the safety of the device by preventing explosive situations.

Due to the separation of the annular space by ribs with blades fixed on them into separate sectors, the contact of the heated raw material with the walls of the central pipe and the area of the waste afterburning mirror are increased, which allows a 15–20% increase in the heat transfer coefficient and a decrease in the heat stress of the furnace.

The totality of the decisions made allows to achieve the maximum effect in the elimination of any organic waste.

Literature

1. Certificate of Sanitary Inspection of the Russian Federation No. 008148.

2. RF patent No. 2027825, cl. E 02B 15/04, A 01C 21/00, 1995.

3. Auto USSR No. 1291791, class G 236 5/20, G 27B 7/28, 1987.

4. RF patent No. 2078112, cl. C 10B 1/10, 53/06, 1994.

Claims (7)

CLAIM 1. A method of eliminating organic waste, including loading the raw materials into the furnace with simultaneous recirculation of the calcined solid heat carrier (ash) into it, forcing and heating the resulting mixture with evaporation of water and burning organic matter in a stream of heated air to form solid and gaseous heat carriers, removing and purification of combustion products, characterized in that in the loading zone, with constant monitoring, by supplying the calcined solid coolant, the temperature of the mixture is maintained at 100-120 ° C, and The fallen water vapor is transferred to the hot ash discharge zone, then, along the entire length of the combustion zone, with intensive mixing of the raw material, air heated up to a temperature of at least 200 ° С is supplied directly above the raw material layer, after burning organic matter, the combustion products are transferred to the afterburning zone using the heat obtained for additional heating of the raw materials in the loading and combustion zones, and then gradually cool them with variable temperature air supplied over the entire length of the afterburning zone. 2. The method according to p. 1, characterized in that when an insufficient amount of ash is obtained, the mineral part is introduced before loading on a return basis, for example sand, crushed limestone, etc., to obtain a total of at least 20 solid heat carrier with the ash wt.% loaded waste. 3. The method according to p. 1, characterized in that the air for burning waste is heated in the heat insulation system of the furnace, while the required degree of heating is achieved by repeatedly blowing excess air through the specified system. 4. A device for the elimination of organic waste, containing a rotary horizontal furnace, consisting of two concentrically arranged outer and central pipes rigidly interconnected by longitudinal ribs with the formation of a sector annular space, vanes for the oncoming movement of waste and annealed solid coolant in their cavities, a spiral channel with an adjustable inlet connected to the annulus and an outlet inward to the loading zone, the lining of the outer pipe in the form of bechayki with heat insulating material, loading and unloading and burner chambers, means for loading waste and evacuating ash, a device for driving blast air, cleaning and removing flue gases, characterized in that at both ends of the outer pipe there are a number of openings closed from the outside by the supply and exhaust air collectors made in the housing of the loading and unloading and burner chambers, and connected to the outer cavity of the lining formed by the outer pipe and intermediate concentrically located both a seagull with spiral channels of the opposite direction on both surfaces, while tubular channels are made into each sector of the annulus at the outlet from the outer cavity of the lining, and tubular channels are made from the inner cavity of the lining on the remaining length of the annulus and above the bottom of the central pipe along the length of the zone combustion, while from the loading zone of the central pipe, an outlet pipe with an adjustable valve to the zone of ash discharge and purification of the flue gases of the loading and unloading chamber was drawn. 5. The device according to claim 4, characterized in that at the beginning of the combustion zone in the Central pipe is made a screen with the possibility of promoting raw materials. 6. The device according to claim 4, characterized in that the spiral channels from the annulus to the loading zone of the central pipe must be at least two with a uniform distribution around the circumference of the central pipe, while a threshold for the concentration of calcined is placed directly behind the adjustable inlet in the annulus solid heat carrier. 7. The device according to PP.4-6, characterized in that the angle of inclination of the longitudinal axis of the furnace with respect to the horizon can reach 30 ° in each direction.