Technique for purifying calcium carbide furnace gas

Abstract

The invention relates to a gas purification process for a calcium carbide furnace. The process is characterized in that introduce the mixed calcium carbide furnace gas and combustion supporting oxygeninto a combustion section at the bottom of a purification tower for partly combustion; then, the gas from bottom to top comes into a purification section at the central section of the purification tower to be purified under the function of the regenerative reduction filler; after purification, most gas is introduced out from the central section of the purification tower; cool the gas below 160 DEG C and dedust; remove the CO2 in the gas after the gas comes into the decarburization and separation system; then use a pressure swing absorption device to separate the CO and H2 and N2. The invention adopts the method of introducing the calcium carbide furnace gas into the purification tower and supplying the appropriate amount of oxygen and the regenerative reduction filler for the purification tower to remove the methane, tar, oxygen and other impurities in the calcium carbide furnace gas after three steps in the purification tower; the three stages comprise the combustion step of the furnace gas, the purification step of the furnace gas and the activation step of the regenerative reduction filler; then after the dedusting and decarburization separation, carbon monoxide and hydrogen as chemical materials can be obtained. The process has the advantages of achieving the comprehensive purposes of waste utilization, energy-saving, emission reduction andhigh value-added utilization for the furnace gas in the production of calcium carbide and improving the economic benefits of the enterprises.

Description

technical field [0001] The invention relates to the technical field of chemical industry, in particular to a process for purifying calcium carbide furnace gas. Background technique [0002] According to Article 3 of Energy Consumption and Comprehensive Utilization of Resources (2) and (3) in the "Calbium Calcium Industry Access Conditions (Revised in 2007)" promulgated by the National Development and Reform Commission: Dust (referring to CO gas) must be comprehensively utilized, and the furnace gas is not allowed to be discharged directly or torched, and the powdery furnace materials generated during the production process must be recycled. The main component of calcium carbide furnace gas is CO, in addition to O 2 , N 2 , H 2 , CH 4 , C n Hm, solid dust. At present, the calcium carbide furnaces of domestic calcium carbide manufacturers are transforming from open, semi-closed to fully closed, but the utilization of calcium carbide furnace gas only stays at the low leve...

AI Technical Summary

Problems solved by technology

At present, the calcium carbide furnaces of domestic calcium carbide manufacturers are transforming from open type, semi-closed type to fully closed type, but the utilization of calcium carbide furnace gas only stays at the low level of combustion heat, and the discharged carbon dioxide gas directly Pollution of the atmospheric environment, no comprehensive utilization in the true sense

[0003] In the production process of the closed calcium carbide furnace, every ton of calcium carbide produced can release 400Nm of furnace gas 3 , where pure CO is about 300Nm 3 , the main component of calcium carbide furnace gas is CO, and also contains a certain amount of oxygen, nitrogen, hydrogen, methane and tar (the tar in the furnace gas is mainly caused by the use of a large number of tar-containing carbon materials such as semi-coke and electrode paste), Theoretically speaking, CO in calcium carbide furnace gas can be used in the production of methanol and synthetic ammonia, and also in the production of carbonylation products such as acetic acid. However, due to the existence of oxygen, methane and tar, the purification and deep processing of calcium carbide furnace gas, etc. The comprehensive utilization process is greatly restricted. Therefore, the situation formed in China is that on the one hand, CO users synthesize a large amount of CO through coal gasification, and on the other hand, a large amount of CO in calcium carbide furnace gas is used as fuel by low-level utilization processes. burned in vain

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