RU1779882C - Method of gas blow-out detoxication - Google Patents

Abstract

SUMMARY OF THE INVENTION: a method includes exposing a pulsed combustion device to pulsating exhaust gas emissions by supplying gas emissions and pulsed combustion exhausts to a layer of refractory bulk material. Part of the neutralized gases in the amount of 5-50% is fed directly into the pulsating combustion chamber. Gas emissions are preheated by process products. An additional fuel, 3 zp, is supplied to the layer of refractory starting material f-ly, 1 ill.

Description

The invention relates to industrial power engineering, in particular to methods for the thermal treatment of steam emissions from industrial enterprises, municipal facilities and other objects polluting the air basin with poisonous, foul smelling gaseous and vaporous substances, in particular for air flows containing undesirable components with small concentration.

Known methods for thermally neutralizing gaseous emissions for cleaning drainage and ventilation exhausts. These methods consist in burning emissions in chamber furnaces using gaseous or liquid fuels. The technological scheme of the process includes the supply of gas emissions to the burner, which also receives fuel, at the outlet of the burner a torch is developed located in the chamber furnace, where the chemical decomposition (oxidation) of harmful substances into harmless compounds (carbon dioxide, water vapor and others

oxides). These methods differ favorably from others (wet cleaning, use of low temperature reactors) with a higher degree of purification, the absence of highly corrosive media, with the exception of wastewater.

The disadvantage of the methods is the obligatory presence of a large reaction volume due to insufficient intensification of stirring, a chemical decomposition reaction, this leads to large dimensions of the neutralizing plants, the requirement for a high temperature level, and high-pressure flash machines.

The prototype of the claimed method is the method when gaseous waste is introduced into the pulsating combustion chamber and the air is sucked in through a mixing nozzle serving as an aerodynamic valve. After combustion, the flue gases are ejected outside, part of them exits the aerodynamic valve with increasing pressure and is again sucked in with decreasing pressure.

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The disadvantage of this method is the short residence time of the neutralized substances in the reaction zone, because Velocities in the device are large (20 - 50 m / s), and the length of the resonance tube at which pulsating combustion is realized is 1.5 - 2 m, therefore, the reliability and completeness of neutralization are reduced, and the allowable costs of gaseous emissions are very small, t .to. they are introduced into the device only through a narrow valve in the center of the combustion chamber, because as the size of this valve increases, the operating mode is interrupted.

The purpose of the invention is to increase the efficiency of the process.

The goal is achieved in that in a known method of burning gaseous emissions, the products of combustion of a pulsating combustion device and gas emissions are fed to a layer of refractory lumpy material, part of the gas emissions (5 ... 50%) are fed directly to the pulsating combustion device, gas emissions are preheated the products of combustion of the pulsating combustion device, during boosts, additional fuel is supplied to the layer of refractory material.

The drawing schematically shows the principle of the method, where 1 is a pulsating combustion chamber, 2 is a layer of lumpy refractory material, 3 is a receiving duct, 4 is an exhaust duct, 5 is a surface heat exchanger, 6 is a connecting duct, 7 is an air pipe, 8 is a fuel pipe 9 - afterburning fuel line; 10 - diffuser duct.

The proposed method of neutralizing gas emissions is implemented as follows.

Fuel (gas, liquid, fuel consumption 5 ... 10 kg / h) is supplied to the pulsating combustion chamber 1 by the fuel line 8, and air enters through the air pipe 7.

With the help of an electric candle, the pulsating combustion chamber is started, its operating mode is set:

Exhaust temperature 900 - 1500 ° С

Average gas velocity 10 - 200 m / s

The amplitude of the velocity pulsations at the exhaust of the pulsating combustion chamber 20 - 50 m / s

The exhaust stream from chamber 1, located in an expanding diffuser duct 10, at the end of which a layer 2 of lumpy refractory material is installed, fills the entire duct, acting on the entire cross-section of layer 2. Chamber 1 works like a gas pump, sucking air from the air pipe 7 and forcing gases into the bed 2. The combustion products are released into the atmosphere through the exhaust duct 4.

The processed gas emissions are fed into the intake gas duct 3 and then passed through the surface heat exchanger 5, with the connecting gas duct used, heated gas emissions are directed to the gas duct where chamber 1 is located. They are washed, additionally heated to 0 and, interacting with the torch, enter layer 2.

Neutralization takes place in a torch after chamber 1 and mainly in layer 2. Toxic organic substances are fed onto the hot surface of the lump refractory, decompose from high temperature and oxidized by atmospheric oxygen coming from air pipe 7. Refractory material - broken brick, pieces

0 fireclay, may contain various catalysts that contribute to the neutralization. The products of burning fuel and the decomposition of toxic or harmful (odorous) substances are discharged outside by an exhaust duct 4

Part of the gas emissions from the duct 6 goes directly to the chamber 1. This part is 5 ... 50% and is due to the properties of the neutralized gas, its

0 concentration, design features, external cooling conditions of chamber 1.

The air in front of the air pipe 7 can be heated in a heater similar to heater 5.

Since chamber 1 has pumping properties, the introduction of additional aerodynamic drag into the decontamination process in the form of a layer 2

0 and heater 5 does not require additional energy costs for pumping gas flows.

To increase the temperature in layer 2, for volley emissions, afterburner

5 of the diagram: fuel is supplied by afterburning fuel line 9.

The effectiveness of the proposed method for the neutralization of gas emissions is to increase the efficiency

0 process due to the intensification of heat and mass transfer in gas flows after a pulsating combustion chamber falling into a developed hot surface of a layer of refractory material. In addition, decontamination reliability is increased due to increased path and response time. These effects are achieved without the use of additional energy due to the operation of pulsating combustion devices.

Claims (4)

1. A method of neutralizing gas emissions by exposing them to the combustion products of a pulsating combustion device, characterized in that, in order to increase the efficiency of the process, the products of combustion of the pulsating combustion device and gas emissions are fed to a layer of refractory bulk material. 0 2. The method according to claim 1, characterized in that part (5 ... 50%) of the gas emissions is fed directly to the pulsating combustion device. 3. The method according to claim 1, characterized in that the gas emissions are preheated by the combustion products of the pulsating combustion device. 4. The method according to claim 1, characterized in that additional fuel is supplied to the layer of refractory bulk material.