What is the approximate range of H2S content in semi-water gas?
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This post was last edited by 654262293 on 2010-8-18 at 12:58. I would like to know what the approximate range of H2S content is in semi-water gas produced by fixed-bed gas generation using briquettes with a ash content of around 23%, a volatile matter content of 5–8%, and combustion promoters added Thank you!
This post was last edited by Yan Qiusheng on 2010-8-20 at 22:00. This issue depends on the S content in the raw coal; the H2S content in semi-water gas is directly related to the S content of the raw coal.
1# pzhmotor should be no less than 1.0, right?
Whether producing gas from briquetted coal or lump coal, the hydrogen sulfide content in the semi-water gas depends on the sulfur content in the raw coal. The poster can provide the sulfur content values for the coal raw materials, and everyone can help analyze them for you!
This post was last edited by pzhmotor on 2010-5-3 at 16:12; there are no S content specifications for their briquettes. Their factory is in Hunan; the briquettes contain a combustion catalyst, but it’s not clear whether there are any sulfur-fixing additives as well. We are not in the ammonia synthesis business; desulfurization is not a key factor affecting production volume, but it does have a certain impact on product quality. Their plant (which also does not produce synthetic ammonia) doesn’t even measure the H2S content in the inlet and outlet towers. I use fixed-bed mixed gas here, with a sulfur content in the coal of less than 1%. (The volatiles content of the briquettes I use is around 12%. I’ve always thought that there is a direct relationship between the sulfur content in the fuel and its volatiles content; this is the case with bituminous coal used in boilers.) From what I know, 80%-85% of the sulfur in the fuel gets converted into substances such as H2S or sulfides. The exit temperature of the furnace in a fixed-bed system is higher than that in a water-gas system; the temperature of the fire zone is around 1100 degrees, and gas production takes place on a continuous basis. The calorific value of gas is also much lower than that of semi-water gas (around 5500 KJ/NM3). I would like to know how big the difference between the two is (with a lower temperature in the flame layer, the efficiency of converting S into H2S is relatively lower). If it’s convenient, could you please tell me the range of S content in the fuel you use, as well as the H2S content at the outlet of the scrubber tower (the inlet of the desulfurization tower)? I’ll make a rough estimate.
Moderator Luohu is right; regardless of the raw materials used, the hydrogen sulfide content in semi-water gas is determined solely by the sulfur content in the coal used as raw material. The hydrogen sulfide content in gasified coke (blue coal) can be as low as 700 mg/Nm3, while it can reach around 1% when high-sulfur coal is used.
This post was last edited by Chemical Gas Purification on 2011-10-26 at 16:32. The type of coal used has a significant impact on the properties of briquettes; if low-sulfur coal such as that from Ningxia is used, the value might be around 0.3–0.4 grams per cubic meter. With coal from Jincheng in Shanxi, it could be 0.8–1.0 grams per cubic meter, while coal from Yangquan in Shanxi results in a value of 1.5–2.5 grams per cubic meter. On the other hand, if high-sulfur coal from regions like Guizhou and Hunan is used, the value rises to 3.5–5 grams per cubic meter. The oxidizer should have little impact on it.