Yisheng 3.2M Two Stage Cold Gas Coal Gasifier

1.What is the coal gasification

Coal gasification is the foundation of gasifying agent and the carbon. The gasifying agent(water vapor and air mixture) flowing through the hot fixed-bed of combustion coal, there are series chemical reaction process. Gasifying agent contained oxygen and steam reaction with the carbon to produce O2 , H2 , CH4, C2H4, N2 among them , the CO H2 CH4 ,CmHn are combustible gases. The main chemical reaction is showing as in the above drawing.

2.Coal gasification theory

Basic chemical reaction Producer gas is made by the gasification agent, which is mixture of steam and air, goes through red-hot fixed burning bed. The oxygen and steam content in the air react with the carbon in the fuel, generate the producer gas with ingredients like CO, CO2, H2, CH4, C2H4, N2 etc.

Reaction of steam and carbon is endothermic reaction: C + H2O= CO + H2

When oxygen and carbon react, then heat output: 2C + O2 =2CO

Reaction of carbon monoxide and steam: CO + H2O = CO2 + H2

Some steam here reacts with carbon monoxide. When every volume of carbon monoxide translates into carbon dioxide, generates the same volume of hydrogen at the same time. In the reducing zone, quick reaction is occurred when the temperature is below 1200 Celsius degree .

CO2 + C = 2CO and H2O + C=H2 + CO

When the coal gas goes through the reducing zone, flammable gas content rises rapidly, carbon dioxide and steam content decrease. Across the reducing zone, a part of coal gas is exported, flows through bottom cyclone and wind cooler, this part of gas is called “downstage coal gas”, its temperature is around 400-550 Celsius degree.

In the carbonation stage, the coals added in the gasifier are dried, preheated and carbonated, generate steam, tar and coal gas, exported from the top of gasifier together, this part of gas is called “up-stage coal gas”, its temperature is around 100-150 Celsius degree.

3.Technical parameter of the two-stage coal gasifier