【Ten Years of Rapid Development in Chemical Equipment】The first low-cost 10,000-ton per year polysilicon production facility in China was put into operation from 2014 to 2018

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On December 28, 2018, Sichuan Yongxiang New Energy Co., Ltd.’s 25,000 tons per year high-purity crystalline silicon production facility came online. Sichuan Yongxiang New Energy Co., Ltd.’s 25,000 tons per year high-purity polysilicon project is part of the company’s first-phase development. This single production facility is the first of its kind in China to have a production capacity of 10,000 tons per year at a cost of less than 40,000 yuan per ton, marking a shift in the production scale of low-cost polysilicon from thousands of tons to 10,000 tons per year. Since 2017, Hualu Company has been responsible for the engineering design of process units such as cold hydrogenation, distillation, reduction, finishing, off-gas recovery, and treatment of waste gases and liquids, as well as tank areas and utility systems, for Sichuan Yongxiang’s polysilicon project. This project utilizes the advanced modified Siemens process available in China, as well as the cold hydrogenation technology developed independently by Hualu Company. Compared with foreign cold hydrogenation technologies, it achieves multiple technological advantages: it innovatively solves the problem of recycling the by-product hydrogen chloride ； Successful innovations in large-scale fluidized bed reactors have resulted in a silicon tetrachloride conversion rate that is 6–8 percentage points higher than that of similar foreign technologies ； By optimizing the design of the heat recovery system, the power consumption for producing trichlorosilane was significantly reduced to 0.2 kW·h/kg, which is half of that in foreign cryohydrogenation technologies ； The developed wet dust removal system combining a venturi and a scrubber, as well as the dry dust removal system using a cyclone and a filter, reduced the silicon powder content in the slurry and improved the operational stability of the system, allowing the cold hydrogenation unit to operate continuously for over 1 year. Technology is productivity; technology equals efficiency. Only continuous technological innovation can provide sustained momentum for the industry. Luhu Company, leveraging its proprietary cold hydrogenation technology and engineering expertise, is committed to the overall progress of the entire industry. Adhering to the principle of being \"half a step ahead,\" it aims to achieve energy savings, reduce consumption, unlock potential, and improve efficiency. By integrating practical production experiences, it actively explores new approaches, embraces innovation, and conducts thorough research. At the Yongxiang project in Sichuan, it has carried out a series of technological developments and upgrades. Through the use of large-scale reduction furnaces along with heat recovery technologies for these furnaces, multi-stage coupled distillation techniques, and exhaust gas recovery and separation methods, it has enhanced the internal circulation of materials. This has enabled full recycling of silicon tetrachloride, a by-product of polysilicon production. As a result, the amounts and types of waste gases, liquids, and solids emitted from the production system have been significantly reduced. The consumption of key raw materials and utility resources has also decreased, and electricity usage has dropped substantially, thereby leading to a significant reduction in production costs. The project is designed as electronic-grade grade 1 product, capable of meeting the requirements for N-type monocrystalline silicon. It is worth noting that the cold hydrogenation core unit features an advanced fluidized bed structure, which improves mass and heat transfer; the one-pass conversion rate of the fourth-generation fluidized bed reactor exceeds 28% ； The distillation purification system employs a polysilicon multi-effect differential pressure coupling energy-saving process technology, which allows the energy consumption of the distillation unit to be reduced by more than 50% compared to conventional processes, thereby saving a large amount of circulating water and steam ； In terms of heat energy utilization, zero steam consumption is achieved through gradient flashing. At the same time, Hualu integrates smart elements throughout the entire process – including engineering design, construction, and operation – to build smart factories by focusing on themes such as safe production, improved efficiency, energy conservation, and intelligent management.