UA81527C2 - Method for decontamination of fume gases of fuel burning units - Google Patents

Abstract

The invention relates to the decontamination of fume gases and can be used in fuel-burning units. A method for disinfection provides for fuel burning in combustion chamber at mode of incomplete burning at minimal possible coefficient of air excess , this retards formation of nitrogen oxides. Fume gases are after-burned in reactor through inclusion of additional gas fuel and additional air with excess coefficient 1.1<1.3, this promotes oxidation of carbon oxide. Temperature in reactor is kept at level of 750-1200 °С. The invention promotes decrease of content of nitrogen oxides and carbon oxide in fume gases without use of catalysts.

Description

special devices intended for the introduction of where: фp - the amount of additional gas fuel, the specified suspension in the combustion products, (|i m/h; insufficient efficiency of smoke disposal Frdg - the amount of flue gases that entered the gases leaving from fuel combustion disposal, m /h; aggregates. Sdg - heat capacity of flue gases, kcal/m3 es;

A known method of flue gas disposal ir - the temperature of flue gases in the reactor, "С; combustion units, taken as ydg - the temperature of flue gases at the outlet of the prototype, which includes the combustion of fuel in the fuel chamber of the combustion unit, the fuel chamber of the combustion unit in b; incomplete mode fuel combustion at a minimum Ovns - heat consumption, released to the possible coefficient of excess air s, and the environment, kcal/h; afterburning of flue gases leaving the Ops - the amount of heat that is reproduced from the fuel combustion unit, carried out in the combustion of carbon monoxide, contained in the smoke reactor, by introducing gases into the reactor, kcal/h, additional gas fuel and additional Chi - heating capacity of additional air | see patent of Ukraine Me47140A, IPC of fuel, kcal/m3,

E2307/00, publ. 17.06.2002|. at the same time, they regulate the supply of additional

The disadvantage of the known method is insufficient air for burning the additional gaseous degree of purification of flue gases from nitrogen oxides and fuel in accordance with the following dependence: carbon, which leave the fuel combustion unit. The process of combustion of flue gases is not where: I dp - amount of additional air, m/h; optimized, namely afterburning takes place Oz - the theoretical amount of oxygen, which is required in a static mode without adjusting the amount and for burning additional fuel, m3/m3; calorific value of additional fuel and Ozdg - amount of oxygen in flue gases, mz/mu; of the amount of additional air supplied to the SoOdg - the amount of carbon monoxide in the flue gases of the reactor. Oxygen content in m3/m3 is also not taken into account; flue gases, which leads to unreasonable Nadg - amount of hydrogen in flue gases, m3/m3; consumption of additional fuel. ор - coefficient of excess air in the reactor,

The task of the claimed invention is 1 со1.8: the development of a highly efficient and economical Фp - the amount of additional gas fuel, a method of neutralization of flue gases m/h; of fuel-burning units, which provides the bottom line. . not reducing the concentration of nitrogen and carbon oxides in "Frdg" - the amount of flue gases that entered the flue gas, due to the control of neutralization, m /h. with. and the formation of combustion gases in When fuel is burned in the fuel chamber of the fuel combustion unit at the stage of the fuel combustion unit process, fuel combustion is established, as well as the regulation of the mode of incomplete fuel combustion such that the afterburning of the flue gases leaving the provides the required composition of flue gases on

More outputs of the combustion unit, namely, with combustion units. i am sun

The problem is solved by the fact that in the minimally harmful coefficient of the excess known method of decontamination of flue gases from the air in the fuel chamber, smoke from fuel combustion units is formed, according to to which (oBO-YABOM Me with the level of the concentration of oxides and 5ot of the fuel gas in the fuel chamber (1000-2000Omg/mU). This is ensured as the fuel-ignition unit is operated in the mode of and - and incomplete fuel combustion with a minimum by adjusting the air supply to the fuel g,: combustion unit chambers, as well as by the possible coefficient of excess air c, as well as the heating of flue gases, which leave due to the control of the hydraulic mode of the fuel combustion unit, of the fuel combustion unit, are carried out in the y and . reactor, by introducing the afterburning of flue gases into the reactor, leaving from the additional gaseous fuel and the additional fuel combustion unit, are carried out into the air, according to the claimed invention, the reactor at a temperature that will be maintained at the temperature in the reactor is maintained at the level of 750- the reactor at the level of 750-1200"C, by introducing up to 12002C, at the same time, additional gaseous fuel is used to burn reactor fuel of gas fuel components of fuel and flue gases and using oxygen, which is contained in flue gases, and additional air, which is also introduced into the reactor. The regulation of flue gases is carried out by regulating the supply of additional gas fuel in accordance with the afterburning regime of flue gases and B by regulating the supply of additional gaseous fuel of the following dependence: y y : y fuel in accordance with the above dependence (1), while regulating the supply of Fdg С dhir - S dgidg/- Aries 7 Ops 4 additional air for burning additional

Fp 7 dp 0) gas fuel in accordance with dependence (2).

The technical problem to which the claimed invention is directed is to reduce the concentration of nitrogen oxides and carbon in the air to the fuel chamber of the incinerator of gaseous waste by lowering the unit, as well as by hydraulic control of the initial concentration of nitrogen oxides due to the mode of the incinerator unit. selection of optimal modes of formation of smoke Limit indicators of the increased content of gases in the fuel combustion unit and their carbon monoxide at the indicated indicators of the afterburning coefficient. The selection of optimal modes of excess air was 1000-10000mg/m3 in the formation of flue gases in the fuel combustion unit flue gases at the exit of the fuel chamber 1. unit is carried out taking into account the initial afterburning of domestic gases, which depart from the theoretical ratio of nitrogen oxides and carbon of the fuel combustion unit, was carried out in different coefficients of excess air c. reactor 5, by introducing to reactor 5 as a result of regulating the regime of additional gas fuel at a temperature that was maintained in reactor 5 at the level of 750-120076 during the afterburning of flue gases in the reactor. at a temperature of 750-12007"C, the combustion process of additional gaseous fuel decreases the concentration of nitrogen and carbon oxides in the reproduced using oxygen contained in the gaseous waste to the maximum allowable in flue gases, and additional air, which also values, which is the technical result that introduced into the reactor 5. Dynamic regulation is achieved in the claimed invention.

In Fig. shown is the combustion control of the amount of additional gas unit, which implements the method of fuel (fp) and the amount of additional air (I dp), neutralization of combustion flue gases that were fed to reactor 5, in accordance with the claimed units. of the above dependencies (1), (2).

The claimed method is carried out in At the same time, such indicators as the fuel combustion unit were taken into account, in particular, the coke amount of flue gases that entered the battery (conventionally shown in Fig.), which disposal (Fd), the heat capacity of flue gases is used in the production of coke. Koksova (Sdu), the temperature of the flue gases in the reactor is 5 (p), the battery, as is known, has from 65 to 77 coke temperature of the flue gases at the exit of the fuel furnace, each of which contains a separate fuel chamber of 1 fuel combustion unit (IDG), a chamber. During the operation of the coke battery, the modes of heat consumption released to the surrounding operation of each fuel chamber are essentially medium (Ovns), the amount of heat, which differs among themselves, depending on the state, is reproduced from the combustion of fuel stacks of the heating system of the coke battery, and the components contained in flue gases (Ops), other factors related to the specific calorific value of additional fuel (dp), production of coke in coke batteries. amount of additional air (IDP), theoretical

Let's consider the possibility of realizing the stated amount of oxygen, which must be supplied for the invention, using the example of one fuel chamber burning additional fuel (Ozh), the amount of coke battery. of oxygen in flue gases (Ozdi), the amount of carbon monoxide

In Fig. fuel chamber 1 of coke in flue gases (SoOdg) is shown, the amount of hydrogen in the flue batteries, to which fuel and air were supplied. For gases (Ngdg) and the coefficient of excess air in this air flow rate was set in such a reactor (o). in such a way as to create conditions for fuel combustion at In connection with the fact that the combustion of an additional minimum possible coefficient of excess gas fuel was carried out with / significant air with. Regulation of fuel and air consumption, by ballasting with flue gases, the concentration of those supplied for combustion was carried out with the additional content of nitrogen oxides, which was reproduced with the help of valves 2 installed on the inlets during the combustion of additional fuel, fuel and air supply pipelines 3, 4 until it was insignificant. Thus, the concentration of the fuel chamber 1 of the coke battery, respectively. Coke gas was used for carbon monoxide in the flue gases at the exit of the fuel quality reactor. 5 decreased to 5-150mg/m3, and the concentration

The coefficient of excess air in nitrogen oxide remained at the level of 200-450 mg/m3 in fuel chamber 1 of the coke battery and was 1.1- (see Table 2). Then the flue gases coming out of 1.3. As a result of the combustion of fuel in the fuel chamber 1 of reactor 5, it was fed to the boiler-utilizer 6, where, with the minimum possible coefficient of excess, they were cooled to a temperature of 150-1902С, air (0-1.1-1.3) was formed and then with the help of a flue 7 were diverted to the excessive content of carbon monoxide with insignificant chimney 8. the formation of nitrogen oxides, which is explained by the high During the afterburning of flue gases, which were released by the activity of atomic carbon, which joins atomic oxygen from the fuel chamber 1 of the fuel combustion itself in the process of combustion. In the unit, as an additional gas fuel, the concentration of nitrogen oxides at the output of using either natural gas or coke fuel combustion unit was reduced to gas, or blast furnace gas, or a mixture of these gases, 250-450 mg/m3 (see Table 1). (The concentration of oxides introduced into reactor 5 in a ratio of 1:2-nitrogen, which is usually formed in fuel 1:20 relative to the amount of flue gases, depending on the chambers of coke batteries, is at the level of the calorific value of additional fuel 1000-1200mg/m3). A decrease in concentration (Ap) is indicated. of nitrogen oxides in the fuel chamber 1 of the coke battery, Examples of the implementation of the method. during the implementation of the declared technical solution, it was provided both by regulating the supply

Research on the implementation of the additional air method (IDP), which was submitted to the applicant, was carried out on the Mo1 coke battery of reactor 5, in accordance with the above

OJSC "Zaporozhkoks" dependencies (1), (2). Yes, the amount of additional

Example 1. gas fuel (Fi) was 10350mZ/h at

The amount of flue gases (fdg) that came from the calorific value of additional fuel (dp) - neutralization - 120,000 mZ/h. The composition of flue gases is 4000 kcal/mU, and the amount of additional air (I dp) - gases leaving the fuel chamber 1 of the coke oven is 35300 m3/h. battery, was the following, in mass. 9o: O2-4.6; СО2-5.8; At the same time, the concentration of carbon monoxide in

NgO-17.3; M2-72.1; 60-0.2. The temperature of flue gases was 12 mg/m3. After that, the gases at the outlet of the fuel chamber 1 flue gases, purified to the concentration of the fuel-ignition unit (Id) equal to the concentration of nitrogen oxides - 367 mg/m3 and carbon monoxide - 12 mg/m3, 300 "C. At the same time, the minimum output of nitrogen oxide was released into the atmosphere. ( 374mg/mU), which was contained in the flue gases, which in Table 1 are data on the concentration leaving the fuel chamber 1, was provided with nitrogen and carbon oxides in the flue gases, which, with the minimum possible excess coefficient, leave the fuel combustion unit, into the air at -1.3. At the same time, the output of carbon monoxide, depending on the ratio of excess air to flue gases at the exit from fuel chamber 17, was 2100 mg/m3. Then, the flue gases leaving fuel chamber 1 were sent to reactor 5, where they were reburned at at a temperature of 91070 s, I The concentration of carbon monoxide (CO) and the coefficient of excess air in the reactor mg/m3 What (or-1.3). As additional fuel 510000 used coke gas of the following composition, 4500-6000 in mass: 0бО2-2.2; 02-11; StNay-2.2; CO-6.3; 1000-3000

СНа-25.3; M2-58.0; Hg2-4.9. Dynamic regulation 400-600 of the afterburning mode of flue gases was carried out by 200-300 regulation of the amount of additional gas 100-150 fuel (fe) and the amount of additional air (I dp), 7100 which were supplied to reactor 5, in accordance with - the above dependencies (1) , (2). Yes, the number of I I I -

Table 2 shows data on the concentration of additional basin fuel (fo) and the composition of nitrogen and carbon oxides in the flue gases after b437m'/h at the calorific value of additional combustion in reactor 5 of fuel-burning additional fuel (dv) - "00okcal/m and the QUANTITY of the unit, depending on the amount of additional additional air (I-dp) - 14834M/h. gas fuel (fp) and additional air (I dp).

At the same time, the concentration of carbon monoxide in the fuel chamber, the amount of flue gases leaving the flue gases at the outlet of reactor 5 was 82 mg/m3, and the concentration of nitrogen oxide decreased in the fuel chamber! and entered the reactor 5, the reactor and I was 120,000-140,000 mZ/h. at a temperature of up to 276 bmg/m3. After that, the flue gases, purified to 270-3202C and the content of O» - 4.4-4.75/, ше . 3; great dane with with o. concentrations of nitrogen oxides - 276bmg/muU, and carbon monoxide - 82mg/m3 were released into the atmosphere.

Example 2. decontamination of the ZOM composition of smoke Temperature Amount of additional Amount | The ends of the gases leaving the fuel chamber 1 of coke flue gases in the gas fuel (fp), additional air and the battery were as follows, in mass. 9b: O2-4.5; СО2-5.6; reactors (in), 7 m/h (dp), m'/h

NeO-1vaA: 00 Me-73Y: 00 СО-05: 0 Ne-0.05.

The temperature of the flue gases at the outlet of the fuel chamber 1 of the fuel combustion unit (ID) was equal to 280°C. At the same time, the output of nitrogen oxide (438 mg/m3), which was contained in the flue gases leaving the fuel chamber 1, was ensured at an excess air coefficient of 1.3. At the same time, the yield of carbon monoxide in the flue gases at the exit from fuel chamber 1 was 1560 mg/m3. Then, the flue gases leaving fuel chamber 1 were sent to reactor 5, where they were reburned at a temperature of 117070 and a coefficient of excess air in the reactor (sr-1.3).Coke gas of the following composition was used as additional fuel, in mass.9o: СО2-2.2;

O2-1,1; StNa-2.2; СО0-6.3; СНа-25.3; Mo-58.0;

But-4.9.

Dynamic adjustment of the afterburning mode of flue gases was carried out by adjusting the amount of additional gas fuel (fa) and the amount of i g / N ki s- Ko Pyshe g i zi | IS ; Lovytrya H.