Principle and advantages of oxygen-coal combustion technology

Principle and advantages of oxygen-coal combustion technology
1、 Principle
The mixture of oxygen and fuel enters the combustion chamber for combustion, and the flue gas generated enters the circulating flue gas channel, and then enters the combustion chamber for combustion again. The fuel is fully combusted, the combustion efficiency is improved, the NOx and soot emissions in the combustion products are reduced, and the clean and efficient combustion is realized.
Since both thermal and fast NOX come from nitrogen in the air, oxygen is used as oxidant, and the generated NOX mainly comes from NOX in the fuel, which will greatly reduce the total emission of NOX.
Oxygen-coal flameless combustion technology is generally divided into three areas: diffusion zone, diffusion power zone and chemical reaction power zone. The combustion process of diffusion zone and diffusion power zone is determined by material diffusion or partial material diffusion, which is represented by the occurrence of flame, such as the combustion technology of oxygen coal with flame. The oxygen-coal flameless combustion technology works in the chemical reaction power zone.
The pure oxygen of oxygen-coal combustion technology comes from liquid oxygen gasification, and high-pressure liquid oxygen is easy to obtain near-sonic oxygen jet. The flue gas external circulation of oxygen-coal flameless combustion technology is used for drying pulverized coal and conveying pulverized coal. Its flow is about one time of the oxygen flow required for combustion. The secondary air oxygen injection flow in the furnace is about 200 m/s, absorbing the carbon dioxide primary air pulverized coal jet, and realizing the strong internal circulation of flue gas is about 25 times. At the same time, due to the large sliding speed between pulverized coal and flue gas, the full premixing of pulverized coal and oxygen can be realized immediately.
2、 Advantages
Oxygen-coal flameless combustion has the following advantages:
1. Save investment and operating costs;
2. C02 conveying pulverized coal jet is conducive to improving the stability of pulverized coal combustion in the furnace;
3. It greatly reduces the conversion rate of N to NO in the fuel (CO2 creates a reducing atmosphere), and at the same time can improve the reburning effect of NO in the circulating flue gas;
4. Adopt flue gas recirculation system to improve coke burnout rate and reduce fuel cost.
Applying flameless combustion technology to pulverized coal combustion, industrialization as soon as possible, reducing the generation of nitrogen oxides and other pollutants, is conducive to alleviating the pressure of environmental pollution and improving the utilization efficiency of non-renewable energy. Therefore, flameless combustion technology has strong advantages and broad application prospects.