A method of burning fuel with a two-stage exhaust gas cleaning

 

(57) Abstract:

The invention relates to the combustion of gaseous and liquid fuels in boilers and other heat consuming installations. A method of burning fuel with a two-step purification of exhaust gases from harmful impurities include in the first stage, the supply of natural gas, and the second is the oxidation of hydrocarbons on the catalyst with additional air in the furnace volume of the first stage in the temperature range from 1800 to C create a reducing gas environment by burning fuel with excess air coefficient is 0.9-1,02 that prevent the formation of oxides of nitrogen, and the second stage do the cleaning gases from nitrogen oxides on the catalyst using the obtained gas-reducing agents and additional feed to the catalyst of the oxidant at temperatures excluding secondary formation of oxides of nitrogen (700-S), and the catalyst install multistage. The invention improves the cleaning efficiency and durability of the catalyst. table 1.

The invention relates to the combustion of gaseous and liquid fuels in boilers and other heat consuming installations.

Known ways of reducing agents are injected hydrocarbons, but on the second zeolite catalyst [FRG N OS 3642018, MKI 01 D 53/36].

The signs consistent with the new technical solution - cleaning is carried out in two stages and the second stage is to use a catalyst.

The reasons that impede the achievement of the technical result in the specified way, is the low efficiency of nitrogen oxides and the complexity of the technology input of hydrocarbons.

The closest in technical essence to the claimed technical solution is the method of burning fuel with a two-step purification of exhaust gases from harmful impurities: in the first stage of oxides of nitrogen in the natural gas is supplied to the catalyst at a temperature of 700-S, and the second is the oxidation of the formed hydrocarbons, carbon monoxide and black carbon on the catalyst with additional air supply [A. S. 1590118, 5 01 D 53/36].

The signs consistent with the new technical solution - cleaning is carried out in two stages and the second stage is used, the catalyst and the air is supplied.

The reasons that impede the achievement of the technical result in the specified way, is the low efficiency of nitrogen oxides, the temperature increase in the second stage of purification, leading Onesti catalyst.

The technical result is achieved in that a method of burning fuel with a two-step purification of exhaust gases from harmful impurities, including at the first stage, the supply of natural gas, and the second is the oxidation of hydrocarbons on the catalyst with additional air supply, characterized in that the furnace volume of the first stage in the temperature range from 1800 to C create a reducing gas environment by burning fuel with excess air coefficient is 0.9-1,02 that prevent the formation of oxides of nitrogen, and in the second stage do the cleaning gases from nitrogen oxides on the catalyst using the obtained gas-reducing agents and additional feed to the catalyst of the oxidant at temperatures excluding secondary formation of oxides of nitrogen (700-S), and the catalyst install multistage.

In the first stage, the lack of air leads to the suppression of the formation of nitrogen oxides and the formation of regenerative environment (CO, H₂). Gaseous reductants generated in the temperature range from 1800 to C (combustion temperature). In the second stage for oxidation of gaseous reducing agents on the catalyst is fed to the oxidizer at temperatures (BEU environment at various stages of purification. In the second stage, samples were taken after each stage of the catalyst. The content of nitrogen oxides in the proposed method after the second stage of treatment is reduced in comparison with the prototype 2 times.

A method of burning fuel with a two-step purification of exhaust gases from harmful impurities, including at the first stage, the supply of natural gas, and the second is the oxidation of hydrocarbons on the catalyst with additional air supply, characterized in that the furnace volume of the first stage in the temperature range from 1800 to C create a reducing gas environment by burning fuel with excess air coefficient is 0.9-1,02 that prevent the formation of oxides of nitrogen, and in the second stage do the cleaning gases from nitrogen oxides on the catalyst using the obtained gas-reducing agents and additional feed to the catalyst of the oxidant at temperatures excluding secondary formation of oxides of nitrogen (700-S), and the catalyst install multistage.