Zhongtian Hechuang’s 1.37 million-ton methanol-to-olefins project completed successful commissioning

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This post was last edited by liaifeng on 2018-9-3 at 09:06. The 1.37 million-ton methanol-to-olefins project of Zhongtian Hechuang completed successful commissioning. Author/Source: Date: 2017-05-03. Clicks: 46. Zhongtian Hechuang’s coal deep-processing demonstration project is a key initiative for the transformation of the coal chemical industry and economic development in the Sulihe Economic Development Zone. At present, the project has completed all process steps and is producing qualified polyethylene and polypropylene, which indicates that China’s largest methanol-to-olefins project is now ready for operation. At the construction site of the Phase II methanol-to-olefins project of Zhongtian Hechuang, company technicians are closely monitoring the reactions in the two high-pressure polyethylene units that have been fed with material for trial operation; this is also the final step to verify that the production line can operate properly. After 5 hours of testing, the entire system responded normally, which means that all the processes in the project have been successfully implemented and production can now proceed. The two methanol-to-olefins units and the two polyolefins units employed in Phase II of the project are proprietary technologies with intellectual property rights owned by Sinopec, **which helps to reduce production costs. Furthermore, the high-end products produced by the three olefin plants imported by the company from abroad sell for 1,500 yuan per ton more than ordinary olefins. Wang Jun, head of the Comprehensive Planning Department at Zhongtian Hechuang Chemical’s subsidiary, said: \"Our plant is designed to produce 1.37 million tons per year. Once it operates at full capacity, it will be able to meet our current shortage of olefin products. By the second half of the year, our entire chemical plant will be ready for commercial operation.\" On April 27, the 250,000 tons per year tubular high-pressure polyethylene unit of Zhongtian Hechuang’s coal deep processing demonstration project was commissioned successfully in just one attempt, producing qualified products. It is reported that the 250,000 tons per year tubular polyethylene plant of Zhongtian Hechuang started using initiators at 22:39 on April 27, 2017, and produced qualified polyethylene pellets at 22:59. The successful commissioning of this unit with a single batch of feed represents another important milestone for Zhongtian Hechuang Chemical’s subsidiary, following the successful commissioning of the first series of units. The facility was constructed by Sinopec Refining & Chemical Engineering 10th Construction Company, with construction starting in May 2014. The EXXON MOBILL high-pressure tubular process technology is employed, with a plant capacity of 250,000 tons per year. Compared with other processes, it features pulse discharging, multi-point feeding, multi-point initiator injection, a reactor with variable diameter, and discharge from an ethylene quenching reactor. This process features a high average conversion rate of around 40%, and the LDPE products produced using it have little gelation and excellent optical properties. The device can produce specialty materials in various grades, which are mainly used in applications such as highly transparent materials, heavy-duty packaging films, and cable materials. In the early hours of April 29, the high-salinity water concentration and crystallization unit at Zhongtian Hechuang Chemical’s subsidiary produced mixed salts. As Sinopec’s first large-scale \"zero-emission\" coal chemical plant, the operation of this facility enables the separation of impure salts from recycled water, transforming liquid waste into solid resources that can be reused. This helps to **protect the local environment and achieve near-zero emissions for coal chemical projects; with continued operation of the facility and further technological improvements, zero emissions will eventually be achieved. For the treatment of industrial wastewater to achieve \"zero discharge,\" the traditional evaporation crystallization technique is widely used in China. This approach requires significant investment and high costs, and its treatment processes still need further improvement. The high-salinity water concentration and crystallization unit at Zhongtian Hechuang Chemical’s branch uses WaterTech technology. This technology combines its own lime coagulation and clarification method with the world’s most advanced forward osmosis membrane treatment technology to create a unique \"zero-discharge\" solution for industrial wastewater with high COD and high salt content. The facility comprises main components such as a forward osmosis unit, a crystallization unit, systems for reducing the temperature and pressure of medium-low pressure steam, condensate recovery systems, circulating water systems, chemical dosing systems, and systems for packaging and transporting miscellaneous salts. It is primarily used to receive and treat high-salinity wastewater generated by wastewater treatment and reuse systems; after treatment, this wastewater is sent to the circulating water system as supplementary water for production. The crystallized salts, after having their moisture content reduced to 80%, are transported for landfill disposal. The capacity of this facility is 120 cubic meters per hour for the forward osmosis section and 30.5 cubic meters per hour for the crystallization section; it operates for 8,000 hours per year, with an operational flexibility range of 50% to 120%. The Zhongtian Hechuang project is currently the world’s largest coal-to-olefins project, with a total investment of 59 billion yuan. At the end of September last year, the first production line was put into operation, producing qualified methanol; currently, the construction of the second-phase methanol-to-olefins project is underway. Once the project is operational, it will be able to produce 670,000 tons of polyethylene and 700,000 tons of polypropylene per year, creating employment for 5,000 people. The project utilizes the S-MTO technology developed through a collaboration between Sinopec Refining & Chemical Engineering and China Petrochemical Corporation. On June 30, 2016, after the main production units of the Zhongtian Hechuang coal deep processing demonstration project were put into operation, the methanol unit produced qualified methanol at 2:30 a.m. on September 24; the loop polypropylene unit produced qualified polypropylene pellets at 9:20 a.m. on October 23; and the linear polyethylene unit produced qualified polyethylene pellets at 3:21 p.m. on October 26. The commissioning of the first series of units in this chemical project was successful from the very first attempt. The Zhongtian Hechuang coal deep processing project integrates the water-coal slurry gasification technology from GE in the United States, the low-temperature methanol washing purification technology from Linde in Germany, the methanol synthesis technology from Lurgi, Sinopec’s independently developed methanol-to-olefins technology (S-MTO), Sinopec’s ST loop polypropylene technology (PP), Ineos’ Innovene gas-phase polypropylene technology (PP) from the UK, ExxonMobil’s polyethylene technology (PE), and Sinopec’s SGPE gas-phase full-density polyethylene technology (PE), among others.