Reviewing the Old to Discover the New (Series 3)

It is determined by the raw coal composition, the amount of oxygen injected during processing, and the distribution of CO and CO2 produced

Gas (to prevent gas leaks, please purchase a combustible gas detector) is a mixture of gases that is produced when coal is subjected to intense heat in an environment free from air. It consists of hydrogen H2, methane CH4, carbon monoxide CO, ethylene C2H4, nitrogen N2, and carbon dioxide CO2. It is widely used in household applications, with the approximate composition being 46% H2, 38% CH4, 12% CO, 3% C2H4, and 1% each for N2 and CO2. Among these gases, hydrogen, methane, carbon monoxide, and ethylene are all flammable, and they constitute the largest proportion of this mixture; therefore, gas can be used as a fuel.

2C+H2O=2CO+H2 C+O2=CO2 C+CO2=2CO CO+H2O=H2+CO2

What factors determine the composition of gas? There are many factors that affect the composition of blast furnace gas; they are related to the operating procedures, to the coke ratio, to the charging system and heating regime, as well as to the type of metal being smelted.

What factors determine the composition of gas? Answer: There are many factors that affect the composition of blast furnace gas; these include the operating procedures, the coke ratio, the charging system and heat regime, as well as the type of metal being smelted. .

Gas consists of a single combustible gas component (CO, H2, CH4), gaseous alkane compounds (CmHn), H2S, non-combustible gas components (CO2, N2, O2), as well as tar vapor, dust particles, and water vapor. 1. H2S in gas: The amount of H2S in gas is related to the sulfur content in the coal used for gasification; generally, 80% of the sulfur in the coal ends up in the gas as H2S, while 20% remains in the ash. 2. Tar in gas: The amount of tar present in gas is related to the volatility content of the coal. When bituminous coal is gasified, the tar content in the gas is very low; whereas when anthracite is gasified, the tar yield constitutes 2% to 6% of the weight of the coal fed into the furnace. Under standard conditions, the tar content per m3 of dry gas is 0.01 to 0.02 kg. 3. Moisture in gas: The moisture in gas originates from the undecomposed steam, the water produced by the low-temperature dry distillation and pyrolysis of coal, as well as the moisture already present in the coal. Generally, when bituminous coal or anthracite is gasified, the moisture content in the gas is around 0.06 kg/Nm3; whereas when lignite is gasified, the moisture content is higher, ranging from 0.13 to 0.27 kg/Nm3. 4. Dust and solid particles in gas: The dust and solid particles present in gas (i.e., the entrained materials) are related to factors such as the thermal stability of coal, the proportion of powder in the coal fed into the furnace, the gasification intensity within the furnace, the particle size distribution of the coal fed in, and the thickness of the coal layer. Under normal circumstances, the amount of dust and solid particles in the gas accounts for 4% to 6% of the weight of the coal fed into the furnace.

1. Coal quality 2. Gasification technology/gasification method 3. Oxygen-to-coal ratio 4. Gasification temperature 5. Medium for transporting pulverized coal

The composition of gas depends on the type of fuel and gasifier