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This design employs the calcium carbide-acetylene process for the production of vinyl chloride. In the gas phase, the reaction in which acetylene and hydrogen chloride combine to form vinyl chloride is thermodynamically favorable; however, under normal conditions the reaction proceeds slowly. Metal chlorides can be used as catalysts, with mercury chloride being commonly chosen for industrial use, usually in the form of a supported catalyst where the carrier material is activated carbon. The reaction equation is: CH≡CH + HCl → CH2=CHCl, with ΔH = -124.8 KJ/mol. Industrial mercury chloride catalysts are typically prepared by impregnation, with the content of the active component, mercury chloride, ranging from 10% to 20%. When mercury chloride catalysts are used, the mechanism for the addition of hydrogen chloride to acetylene involves acetylene first reacting with mercury chloride to form an intermediate, vinyl chloride mercurate, which then decomposes upon contact with hydrogen chloride to yield vinyl chloride. Additionally, the intermediate may also react with mercury chloride to form dichloromercuric dichloroethane, which subsequently converts into mercurous chloride and dichloroethylene. During the production process, since the concentration of hydrogen chloride in the reaction system is much higher than that of mercury chloride, the possibility of forming dichloroethylene is very low. When there is an excess of hydrogen chloride, the vinyl chloride produced may further react with the excess hydrogen chloride to form 1,1-dichloroethane, which serves as a by-product of the reaction. Conversely, when there is an excess of acetylene, the excess acetylene may reduce mercury chloride to mercurous chloride, or even convert it into metallic mercury, thereby deactivating the catalyst. Therefore, the possible by-products of the reaction between acetylene and hydrogen chloride are dichloroethane and dichloroethylene. Acetylene and hydrogen chloride mix together and enter the reactor to carry out the reaction. The gas after the reaction enters a water scrubber, where hydrogen chloride is removed by water. The gas then enters the alkali scrubber, where 10% NaOH aqueous solution is used to remove any remaining hydrogen chloride. The gas after washing proceeds to the first pre-cooler, where the water contained in the gas is condensed. The uncondensed gas enters the compressor and is compressed to 0.5 Mpa. It then enters the second pre-cooler to further ensure that any trapped moisture is completely condensed. And then it enters the condenser. The condensed liquid enters the primary distillation tower for separation. The non-condensable gases, along with the gases coming from the top of the initial distillation tower, are sent to the exhaust gas condenser; after being condensed using chilled brine, the exhaust gas is released. The bottom product of the initial distillation tower is fed into the rectifier, where the vinyl chloride product is obtained at the top of the tower. 2.1 Process Flow Diagram Figure 2-1 Process Flow Diagram