Acetylene gas purification device and its process

Abstract

The invention relates to an acetylene gas purification device and a process thereof. The device comprises a concentrated sulfuric acid acetylene purification system, a waste sulfuric acid pyrolysis purification system and a flue gas purification acid production system, wherein the concentrated sulfuric acid acetylene purification system comprises a purification tower; an acid storage section, a packing section, a bubble cap section and a demisting section are sequentially arranged in the purification tower from bottom to top; the waste sulfuric acid pyrolysis purification system comprises a waste sulfuric acid storage tank, a pyrolysis furnace and a waste heat boiler which are sequentially communicated with one another; the waste sulfuric acid storage tank is communicated with the acid storage section; and the flue gas purification acid production system comprises a flue gas washing tower, a flue gas cooling tower, a water mist separator, a sulfuric acid drying tower, a heat exchanger, a sulfur dioxide conversion tower and an absorbing tower. According to organic combination of the three systems, the byproduct such as waste sulfuric acid which is difficult to treat is avoided in the system, the sulfuric acid is recycled in the novel system, and the normal operation requirement can be met by supplementing a small amount of the sulfuric acid only. The device disclosed by the invention has typical clean production characteristic and also has the advantages of safety, reliability, environment friendliness, economical efficiency, good acetylene gas purification effect and the like.

Description

technical field [0001] The invention relates to an organic raw material purification device and its process, in particular to an acetylene gas purification device and its process. Background technique [0002] Acetylene is an important basic organic raw material, which is often used in the production of vinyl chloride and chemical fibers. In industry, calcium carbide is generally used as raw material to produce acetylene. Pure acetylene is a colorless and odorless gas. The acetylene produced by calcium carbide is often mixed with PH 3 、H 2 S and other impurities have a special and unpleasant odor. In industrial applications, it is necessary to purify the crude acetylene gas to obtain pure acetylene gas for industrial production. [0003] In the prior art, there are mainly two processes for purifying crude acetylene gas. One is the sodium hypochlorite purification process for acetylene: in the calcium carbide method for the production of vinyl chloride, sulfur and phosphoru...

AI Technical Summary

Problems solved by technology

There are three disadvantages of the sodium hypochlorite acetylene purification process: (1) poor safety, free chlorine in the sodium hypochlorite solution can form explosive chloroacetylene with acetylene; (2) the amount of wastewater generated in the process is relatively large, 9 to 9.5 tons of wastewater per ton of PVC theoretically, Although about 70% can be reused, the total amount of wastewater is still large (the amount of wastewater from a 300,000-ton PVC plant is nearly one million tons), and the treatment cost is high; (3) Due to the reuse of purified sodium hypochlorite wastewater, the content of chloride radicals in calcium carbide slag High, unable to meet the circular economy project of cement clinker made from carbide slag

However, in the industrialization process of the new process of purifying acetylene gas with concentrated sulfuric acid, many difficulties have also been encountered in the actual operation process. Among them, there are two main engineering problems that need to be solved: 1. Compared with other alkynes, acetylene has relatively high stability. Poor, easy to decompose into carbon and hydrogen

According to preliminary statistics, the process of purifying acetylene gas with concentrated sulfuric acid requires acetylene gas for purifying one ton of PVC, and the by-product of waste sulfuric acid with a concentration of 80-85% is 20-25Kg. , 8,000 hours / year) about 10,000-12,500 tons; if calcium carbide slag is used for neutralization treatment, about 25,000-31,000 tons of solid waste will be produced, which will cause huge environmental pressure on enterprises

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