UA124992C2 - METHOD OF COMBUSTION OF NATURAL GAS - Google Patents

Abstract

A method of burning natural gas, which includes mixing it with an additive. 3 to 30% of carbon dioxide is added as an additive before the natural gas enters the boiler room or other gas-using equipment at the gas distribution station. This is followed by molecular mixing.

Description

The invention belongs to methods of burning fuel. The method can be used for burning natural gas in boilers or other fuel-using equipment.

A known method of burning gaseous fuel (AS USSR Mo 817387 cl. E 23 O 13/00, 1978 (54) (57) (Gas Institute of the Academy of Sciences of the Ukrainian SSR, authors G.F. Naydenov, O.S. Kush), in which the peripheral the swirling air flow zone is supplied with radial jets of fuel, and recirculation gases flow into the zone near the axis in an amount exceeding 50 95 of its total consumption.

Part of the mixture of fuel and recirculation gases is sucked into the rarefaction zone of the swirling air flow, and the other amount of the mixture creates a direct current jet. Recirculation gases mixed with part of the gaseous fuel, the amount of which exceeds 50-95 of its total consumption, are fed by radial jets into the peripheral zone of the swirling air flow, the amount of which exceeds 50-95% of its total consumption, and the air is pre-mixed with part of the recirculation gases. But in this case, the required quality of molecular mixing is not ensured natural gas with ballast gases.

A method of burning gaseous fuel is also known (50 1270491 АТ кл. Е 23 С 11/00), in which air is supplied in a swirling flow and part of the fuel mixed with ballast (additive) is introduced along its axis at a given concentration of the latter. On the periphery, the rest of the fuel is introduced in the form of radial jets in order to reduce the concentration of nitrogen oxides in the combustion products. Part of the fuel injected in the form of radial jets is pre-mixed with ballast, the concentration of which is maintained equal to the concentration of ballast mixed with part of the fuel injected along the axis of the air flow.

The use of fuel combustion products as a fuel additive has low environmental efficiency, and also reduces the safety of fuel transportation due to the presence of oxygen in the additive. When the additive is added directly in the burner device, deep molecular mixing of it with the fuel is not achieved. There is also a well-known method of adding an additive that reduces the formation of nitrogen oxides only on modernized fuel-using equipment.

The basis of the invention is the task of improving the method of burning natural gas, in which, as a result of replacing the fuel combustion products with carbon dioxide as an additive, as well as changing the place of its supply to the gas pipeline, a decrease in explosiveness is ensured

Due to the method and improvement of fuel mixing with carbon dioxide at the molecular level, and due to this, the formation of nitrogen oxides is reduced, which leads to an improvement of the environmental condition of the environment.

The task is solved due to the fact that in the method of burning natural gas, which includes mixing it with an additive according to the proposal, as an additive before the natural gas enters the boiler room or other gas-using equipment at the gas distribution station (GRO), from 3 to 30 95 carbon dioxide is added , after which their molecular mixing is carried out.

An additional distinctive feature is that the use of carbon dioxide as an additive is carried out from the waste gases of boilers or contact economizers.

The set of distinctive features of the proposed method allows you to solve the task because carbon dioxide does not contain oxygen, which is in the combustion products in the amount of 3-8956, which is unacceptable in gas networks, and therefore the mixture of carbon dioxide and fuel is explosion-proof. The efficiency is also higher when using pure carbon dioxide than the same amount of combustion products, which reduces the formation of nitrogen oxides and improves the environmental condition of the environment.

The proposed method is shown in the drawing. The method of burning natural gas is carried out as follows. In advance, at the gas distribution station in front of the boiler room, carbon dioxide in the amount of 3 to 30 95 of the volume of natural gas is mixed with the natural gas pipeline. At the same time, molecular mixing of the natural gas and carbon dioxide mixture is carried out on the site from the gas station to the boiler house and other consumers. Next, the mixture of natural gas and carbon dioxide is fed to the burner devices of the boilers, where it is burned. After burning the mixture, at the exit from the boiler, carbon dioxide is taken from the combustion products, which is captured from the water in a contact economizer (or other device), which is installed behind the boilers of the boiler house. Next, the carbon dioxide that was captured in the contact economizer is again supplied to the natural gas pipeline at the gas distribution point.

Example 1 (according to the closest analogue). Natural gas with a consumption of 0.07 mz/h. fed by radial jets into the peripheral zone of the swirling air flow with a flow rate of 1.5 m3/h, along the axis of which a mixture of recirculation gases is fed in the amount of 0.08 m/h. and natural gas in the amount of 0.08 m3/h. The flow of natural gas directed by radial jets,

pre-mixed with the flow of recirculation gases (0.07 m3/hour). The total consumption of recirculation gases is 0.15 mz/h, which corresponds to a degree of recirculation of 10 95. The concentration of recirculation gases in axial and radial fuel is the same and amounts to 1 m3/m3. The concentration of nitrogen oxides is 69 mg/m3. And in the case of using a pre-prepared mixture of natural gas and carbon dioxide, the concentration of nitrogen oxides is 36 mg/m3.

Example 2 (according to the proposed method). 3000 nmZ/hour is supplied to the boiler room with 3 TVG-8 boilers. natural gas with a content of 96 95 SNa. Thus, 2880 nm3/hour is supplied to the boiler. (2056 kg) of methane, during combustion of which the following reaction is obtained:

СНаю202-7.52М2-0О2-7.52М2а-2НО 16 44 2056 kg 5654 kg 5654 kg or 2879 nm3 СО». At the same time, the output of MOX during combustion in the boiler is 180 mg/m3.

During pre-mixing at the gas station, 30 95 of carbon dioxide additive (1285 m of CO") is mixed with 3000 m of natural gas, which is up to 30 95 of the total amount of CO" contained in the combustion products and captured in the contact economizer. At the same time, the formation of nitrogen oxides decreases from 180 to 70 mg/m, i.e. lower than EU standards.

In the emissions of widespread powerful water heating boilers PTVM-50 and PTvM-100, the concentration of MOx is 130-190 mg/m?, and with the repeated use of 3095 СО" and its preliminary mixing with natural gas, it is not higher than 65-95 mg/mU, that is, less, than required by EU regulations, - 100 mg/m3.

Example 3. The same as in example 2, but the amount of additive is additionally selected: 3, 5, 7, 10, 15, 20, 30 95.

A comparison of the work efficiency of the nearest analog and this invention is given in the table.

Table

Test indicators of the closest analogue and this invention

Increase of 2. efficiency at

Quantity mode. g.:

Y and Y nut tes,

U, products of fuel combustion carbon dioxide of combustion on So", times shk o PO I PO I POOOOOOOOO UNO NO 2 | 5 |! 1 Her 6 | 60 6 HER 20 2 | shB 15 (B | (UBB | 7/7 35 shSh (

Laboratory studies conducted by the authors (the results are shown in the table) showed that the replacement of combustion products with carbon dioxide as a ballast allows for the same amount of ballast to reduce the output of nitrogen oxides in the combustion products by 2.6-6 times. With a further increase in the content of carbon dioxide more than 3095, there is a decrease

From the effectiveness of the method and the stability of burning with the possibility of the torch breaking off and its extinction.

In the proposed method, in comparison with the closest analogue, there is complete molecular mixing of carbon dioxide with natural gas, due to this reduction in the formation of nitrogen oxides when adding carbon dioxide will be 2.6 times greater than when adding the same amount of combustion products (corresponds to the concentration of ЗО 95 additives mixed with natural gas). In addition, a reduction in the emission of nitrogen oxides in household appliances, industrial and energy equipment is achieved, which will ensure compliance with EU standards.

Also, the addition of carbon dioxide to gas networks is safe in terms of explosiveness, in contrast to the addition of combustion products, which contain a certain amount of oxygen - 3-8 95, which is unacceptable in gas networks.

Claims (2)

FORMULA OF THE INVENTION 1. The method of burning natural gas, which includes mixing it with an additive, which is distinguished by the fact that, as an additive, before the natural gas enters the boiler room or other gas-using equipment at the gas distribution station, from Z to ЗО 95 of carbon dioxide is added, after which their molecular mixing is carried out . 2. The method according to claim 1, which differs in that the use of carbon dioxide as an additive is carried out from the waste gases of boilers or contact economizers. tent of public consumption in kOaMmzhnalentsi ROS pd kva | directness Havaluvalne ihetvdni, etc.) ! taenergatniaa VEVlyaViV, | ! Vodovaumnani, kukhov and pzyyuehe an i!