Composition of calcium carbide exhaust gas

I have done it — CO: 68%-72%； CO2: 0.7%-2.5% ； O2: 0.7%-2.5% ； N2: 15%-20% ； H2: 5%-10%, trace amounts of CH4, C2H2, etc.

What you’re describing doesn’t seem to be the exhaust gas from a closed calcium carbide furnace. Why are the levels of O2 and N2 so high? What I need is a complete analysis; ideally one that includes 100% of the data. This is especially true for those gas components in small quantities that can be harmful as a result of transformations. I’m not sure where I can obtain a complete analysis of such gases

Some literature reports it as: CO-84.5%； N2-7.47% ； H2-4.73% ； CO2-2.5%, CH4-0.3%, other harmful substances-0.5%.

This post was last edited by xwtsq on 2010-4-12 at 10:34. The concentrations of various components in the carbide furnace exhaust fluctuate throughout the production cycle, and these fluctuations are quite significant. I don’t understand the meaning of “gases that are harmful to transformations”.

Substances that are harmful to the conversion catalyst, such as S, P, As, Cl, and organic compounds, are to be used to produce methanol from calcium carbide exhaust gas

What purification process is used in the unit employed by the original poster?

The composition of calcium carbide exhaust gases is quite complex, and many companies want to make use of them but are unable to remove the impurities! Does any member have detailed data on the components of calcium carbide exhaust gases? Please share it! 6#hm567, where is your company located? How to solve these problems! “\"Gases that are harmful to transformation\" probably mean that if these gases are to be utilized, they must definitely go through a transformation process first!

It’s not possible to achieve 100% accuracy; there are many trace components that are likely still difficult to identify and quantify

A colleague in the marine industry conducted an analysis (which can be found under \"Technical Solutions for Purifying Calcium Carbide Furnace Exhaust Gases\"); since the conditions in different factories vary and the composition of the exhaust gases differs as well, we are currently carrying out gas analysis, and once it’s completed, the design institute will develop a solution. Appendix: Component Sequence Number, Name, Chemical Formula, Percentage Content, Content in g/m³
1 Carbon monoxide CO >74～84.5
2 Hydrogen H2 <2
3 Methane CH4 <0.5
4 Carbon dioxide CO2 <2～10
5 Nitrogen N2 <1～8
6 Oxygen O2 <0.2～0.6
7 Others <0.1～1
8 Hydrogen cyanide HCN <0.3 mg/m3
9 Sulfur compounds Hydrogen sulfide H2S <519 mg/m3
10 Thiol RSH <250 mg/m3
11 Carbonyl sulfide COS <268 mg/m3
12 Carbon disulfide CS2 <3165 mg/m3
13 Elemental phosphorus P4 <25mg/m3
14 Phosphine PH3 <20mg/m3
15 Arsenic hydride AsH3 <0.3mg/m3
16 Fluorides (F) SiF4 <mg/m3
17 Dust <50mg/m3
18 Gas temperature Room temperature
19 Gas pressure Slightly positive pressure
20 Total

In 2009, Ningxia Dadi Metallurgical and Chemical Co., Ltd. produced 46,000 tons of synthetic ammonia using the exhaust gas from calcium carbide furnaces, thus becoming the only company in the world to produce synthetic ammonia from such exhaust gas at that time. Through a year of trial operation, Dadi Metallurgy Company has developed purification technologies for calcium carbide furnace exhaust gases, such as high-temperature tar and oxygen removal as well as low-temperature dust removal. It also mixes the low-oxygen content syngas produced by 2 backup fixed-bed gas generators with the calcium carbide furnace exhaust gases, which have an oxygen content as high as 1.5%–2%. It seems that such a high oxygen content is indeed possible. Who knows anything about the current production processes at Ningxia Dadi Metallurgy and Chemical Co., Ltd.? Please share your insights