SU823758A1 - Method and apparatus for burning photomaterial wastes - Google Patents

Description

one

The invention relates to methods and devices for burning solid waste of photographic materials (such as photographic paper, photographic films, photographs, etc.) containing organic and mineral substances, and can be used in folk farms as a result of activity. which produces the waste.

Methods are known for burning solid waste in drum furnaces, including grinding and feeding waste 1}, transporting waste and ash inside the furnace with a screw and removing flue gases and L2J ash, with afterburning of flue gases in a separate burner 4.

The disadvantages of the known methods are the low quality of the ash and the presence of underburning products in it, which requires additional costs for further processing, as well as the loss of the valuable ash product when burning photographic materials - silver;

The closest in technical essence and the achieved result is a method of waste incineration, including the reception and supply of waste, burning them in a drum furnace

underpressure during transportation of waste and ash by a screw, provided with openings for injecting air into waste, treatment of ashes and gaseous products 5.

A device for implementing the method includes devices for receiving and supplying waste, a rotary drum furnace with loading and unloading chambers, a screw, devices for supplying air, and processing ash and flue gases.

The disadvantage of this method

and the device is poor in ash quality due to its slagging due to the uneven layer burning of solid waste, leading to local temperature rises to and above, the molten ash is aggregated into chunks in which a large amount of carbon remains. Reducing the amount of air supplied, as well as directly introducing it into the waste layer evenly | along the length of the furnace, does not translate into this deficiency. When processing such ash, large losses of the target silver product are observed.

The purpose of the invention is to improve the quality of the ash and the reliability of the process of burning solid waste photographic materials.

The goal is achieved by the fact that in the method of burning waste photographic materials, including the reception and supply of waste, heat treatment of them under dilution and simultaneous transportation and processing of solid and gaseous combustion products, the waste is burned in three stages, and in the first stage thermal decomposition of the waste is carried out during gradual increasing the temperature of the waste due to mobile contact with the heated surface, and gaseous decomposition products are removed in the zone of their formation, in the second stage suschestvl dissolved tverDBK burning. products of thermal decomposition at 800-850 ° C and countercurrent movement of gases and solid products, and in the third stage, the combustion of gaseous products of thermal decomposition is carried out.

A device for carrying out the method, comprising means for receiving and feeding waste, a rotary drum furnace with loading and unloading chambers, an auger and an air supply unit, processing ash and flue gases, is provided with a thermal decomposition chamber provided with openings in its upper part for disposal. gaseous products, and a window for unloading solid decomposition products at the end of the chamber and located inside a rotary drum furnace so that the window for unloading solid decomposition products is a loading chamber in the rotary kiln and the screw is placed in the thermal decomposition chamber.

The drawing shows a device for carrying out the method.

A device for burning solid waste of photographic materials contains a hopper 1, a dispenser 2, a screw 3, a thermal decomposition chamber 4, a front head 5 (discharge chamber) of a drum furnace, a rotating drum b, a rear head 7 (loading chamber) of a drum furnace, a flue gas burner 8 , holes 9 for removing gaseous decomposition products, window 10 for outputting solid | (1X. Decomposition products, ash removal and averaging unit 11. The thermal decomposition chamber 4 is a tube with a screw inside, part of which, having openings 9 in the upper part of the tube and a window 10, is located inside a rotary drum countercurrent furnace. Thermal decomposition chamber 4 connected to the dispenser 2 outside the heating zone. In the front head of the furnace 5, devices 12 and 13 are placed for supplying air and fuel. The rotating drum 6 tilts towards the front head. The burner 8 is a cylindrical chamber with Modes having a tangential channels. for introducing the flue gases and air. afterburner located at the rear of the furnace head.

The implementation of the method is carried out with the operation of the device as follows.

After the furnace is heated up, shredded photographic waste is fed into the thermal decomposition chamber 4. When moving and mixing with the screw 3, the waste is gradually heated and gasified by contact with the heated walls of the chamber. The gaseous decomposition products are removed from the chamber through the holes 9 due to the dilution created in the furnace drum, and the solid decomposition products are removed by a screw through the window 10. The gaseous and solid decomposition products are burned in the drum furnace when air is added and 800-850 ° C. Solid decomposition products are transported towards the movement of air and flue gases by tilting and rotating the drum. The flue gases are directed to the afterburner 8, where they are subjected to additional oxidation of the products of incomplete combustion contained in them under conditions of intense twist of the gas stream at a temperature and excess air necessary for FULL oxidation of the products of combustion.

The waste in chamber 4 is heated by heat — from the combustion of gaseous and solid decomposition products in a drum furnace. At this temperature, the drum furnace is maintained in the range of 800-850 ° C by controlling the air supply and waste. The upper limit is limited by the ash melting point, and the lower limit by the process stability. Due to the endothermicity of the decomposition processes — waste in chamber 4, an increase in local temperatures in the layer is excluded than the temperature in the furnace drum. Gaseous decomposition products burn out of the bed along the entire length of the furnace and their temperature. burning regulate the amount of air supplied. The movement of solid decomposition products towards the flow of flue gases and air ensures their gradual and reliable ashing in an atmosphere with varying oxygen concentration. The oxygen concentration varies from 0-5% at the loading end of the drum to 21% at the discharge end.

The proposed sequence of stages and conditions for carrying out the process of burning photo materials provide high quality ash, characterized by the absence of slag and carbon.

The arrangement of a portion of the thermal decomposition chamber inside the countercurrent drum furnace allows the heat from the combustion of decomposition products to be used for the gradual heating and gasification of the waste during its transportation inside the chamber with a screw.

Placing the holes 9 in the upper part of the body and along the entire length of the chamber located in the drum furnace removes the gaseous decomposition products directly in the zone of their formation and incineration in the upper part of the drum b, which prevents local overheating of the waste in the chamber and ash in the drum.

The location of the window 10 at the boot.: At the end of the furnace drum, the waste time in the high (temperature zone, which makes it possible to shorten the drum length without changing the time of heat treatment of the waste, increases.

Claims (5)

1. A method of incineration of photo materials waste, including acceptance of waste supply, heat treatment during vacuum and simultaneous transportation and processing of solid and gaseous combustion products, characterized in that, in order to improve the quality of the ash and reliability of the incineration process, the waste is burned in three stages, in the first stage, thermal decomposition of the waste is carried out with a gradual increase in the temperature of the waste due to mobile contact with the heated surface, and gaseous decomposition products al dissolved in their formation zone, in the second step is carried out combustion of solid thermal decomposition product at a temperature of 800-850 0 and countercurrent flows of gases and solids, and the third stage is carried out post-combustion gas & different thermal decomposition products. 2. A device for carrying out the method according to claim 1, comprising means for receiving and feeding waste, a rotary drum furnace with loading and unloading chambers, an auger and devices for supplying air, treating ash and flue gases, of which In order to improve the quality of the soils and the reliability of the combustion process, it is equipped with a thermal decomposition chamber, made with openings in its upper part, for the removal of gaseous products, and a window for discharging solid decomposition products at the end of the chamber and placed inside a rotary drum furnace in such a way that 5, a window for discharging solid decomposition products is located at the feed chamber of the drum furnace, and the screw is placed in the thermal decomposition chamber. Sources of information taken into account in the examination 0 1. Patent of France No. 2218801, cl. F 23 G 5/06, 1976. 2. US patent number 4009667, cl. F 23 G 5/12, 1978. 3. Japan patent number 52-10313, 5 cl. F 23 G 5/06, 1971. 4. Thermal methods for waste disposal. L., Himi, 1975, p. thirty. 0 5 .. Patent of France 2309799, cl. G 23 G 5/00, 1978.