【Ten Years of Great Progress in Chemical Technology】The ethylene-based vinyl chloride process package with an annual production capacity of 450,000 tons, developed independently, was approved between 2027 and 2023

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Looking at the development of chemical technology over the past decade, we celebrate the prosperity and strength of modern China. This is just a starting point to encourage further discussion among everyone; with your participation, things will become even more interesting. [Ten Years of Progress in Chemical Equipment] – Continuous updates and summaries are available; feel free to join the discussions: https://bbs.hcbbs.com/thread-3576046-1-1.html. It’s important to enhance quality awareness and promote high-quality development. ----------------------------------------- On September 27, 2023, the ethylene-based vinyl chloride production process package, developed by Shandong Kaitai Technology Co., Ltd., passed the expert evaluation conducted by the Shandong Chemical Industry Information Association. Experts believe that this technology uses ethylene and chlorine as raw materials to produce vinyl chloride; its raw material supply chain and production process are in line with **industrial policies, all key equipment can be manufactured domestically, and its technical specifications meet international standards. 　　The evaluation experts believe that this process uses medium-temperature chlorination for direct chlorination, resulting in few by-products and high product purity. The ethylene oxychlorination reaction employs a fluidized bed process and domestically produced catalysts; the reactor has a simple structure that eliminates hot spots and thermal stagnation, while also producing medium-pressure steam at 1.0 MPaG. Dichloroethane cracking is carried out using a box-type cracking furnace with gas-phase feeding, resulting in few side reactions and efficient utilization of thermal energy. All key equipment in the process package can be domestically produced. 　　Regarding the safety and environmental protection issues that are of particular concern in the production of vinyl chloride, the review experts believed that the direct chlorination unit, oxychlorination unit, and cracking unit included in the process package involve **highly regulated hazardous chemical processes; the process safety control measures are reliable, and the safety facilities installed meet the requirements of **relevant laws and regulations. Appropriate environmental protection measures have been put in place for the disposal of the three types of waste generated, ensuring that their discharge meets the required standards; the treatment of these wastes complies with **relevant regulations. 　　“The ethylene-based process we have developed requires 0.464 tons of ethylene per ton as the main raw material, 0.584 tons of chlorine per ton, and 0.04 kilograms of catalyst per ton. ”said Hu Zimin, R&D manager at Kaitai Technology. 　　According to Xiao Hao, director of the Kaitai Technology Research Institute, vinyl chloride is an important monomer for synthesizing polyvinyl chloride. Currently, the production of vinyl chloride mainly relies on two processes: the acetylene method (calcium carbide method) and the ethylene method. Globally, the ethylene route accounts for 70% of vinyl chloride production capacity, while in China it accounts for only 23%. Against the backdrop of stricter energy conservation measures, tighter emission controls, and intense environmental pressures in the country, it is an inevitable trend to use the ethylene method for producing vinyl chloride. Currently, most of the vinyl chloride production facilities in China that use the ethylene process have adopted foreign technological processes; there is no complete domestic technology for producing vinyl chloride via the ethylene process yet. 　　The acetylene process generates large amounts of calcium carbide slag, and the high energy consumption in producing the raw material calcium carbide limits its application. It is understood that on March 7, 2022, the Ministry of Ecology and Environment issued the \"Opinions on Further Strengthening the Prevention and Control of Heavy Metal Pollution,\" requiring the prohibition of the construction of new vinyl chloride production facilities that use the acetylene process with mercury. **The draft \"Guidelines for Industrial Structure Adjustment (2023 Edition)\) issued by the National Development and Reform Commission lists vinyl chloride production plants that use high-mercury catalysts as processes belonging to the category of prohibited outdated technologies, while listing vinyl chloride produced by the acetylene method as a process belonging to the category of restricted outdated technologies. In contrast, the advantages of the ethylene process in terms of raw materials, product quality, environmental protection, and energy consumption contribute to its scalable development. At the same time, with the technological advancements in coal chemical and biomass chemical industries in our country, the production of ethylene using coal and bulk biomass as raw materials is gradually becoming an emerging industry, and the raw materials for this ethylene production process will also become more abundant. 　　The ethylene-based vinyl chloride process package that has passed the evaluation this time specifically includes units for direct chlorination of ethylene, oxychlorination of ethylene, purification of dichloroethane, cracking, and purification of vinyl chloride. 　　In the direct chlorination unit for ethylene, the raw materials ethylene and chlorine undergo a chlorination reaction to produce dichloroethane. After vaporization, dichloroethane is condensed into a liquid phase in a condenser; part of this liquid is returned to the reactor, while the rest is sent to the dichloroethane purification unit for further refinement.