Cycle-free methanation coal-to-gas process

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I pioneered the cycle-free methanation process for coal-to-gas production. Author/Source: China Chemical Industry News, Date: May 25, 2016. Clicks: 13. This approach overcomes traditional methods and reduces reliance on imports. After years of research, China has developed new techniques for cycle-free methanation, as well as technologies related to methanation catalysts and key reactor components, thereby achieving a revolutionary innovation over traditional processes. As a result, China’s coal-to-natural gas technology is now among the world’s most advanced. This is news from the 2016 (2nd) International Symposium on New Coal Chemical Industry in China, held in Qingdao from May 21–22. Shenwu Group’s Beijing Huafu Engineering Co., Ltd., in collaboration with companies such as Dalian Rike and China National Coal Group Longhua, developed this new methaneation process without a recycling cycle for the first time in the world over a period of 8 years. It is understood that for the large-scale coal-to-natural gas projects that have been completed or are under construction in China, all of their core methanation units employ foreign cyclic methanation processes. The reaction temperature in this process is controlled by adjusting the volume of the circulating gas, and it has disadvantages such as high volumes of circulating gas requiring high-temperature circulation compressors, reliance on imported core equipment and catalysts, high investment and energy consumption, and a tendency to experience temperature spikes. According to Wang Qinya, general manager of Beijing Huafu Engineering Co., Ltd. under Shenwu Group, the new process developed by the company boasts four innovations and advantages compared to traditional methods. First, the recycle gas compressor was removed, enabling the localization of process technologies, catalysts, and key equipment; as a result, the overall energy consumption of the plant was reduced by more than 25%, while investments were cut by over 20% ； Secondly, through hierarchical adjustment of the hydrogen-to-carbon ratio, precise control over this ratio is achieved, resulting in more stable and easier-to-manage product quality ； Third, a self-developed high-temperature resistant methane catalyst is used, offering better cost-performance and lower operating costs ； Fourth, an axial radial methanation reactor equipped with a built-in waste heat boiler has been developed; it features a simple process flow, is easy to scale up, and reduces the investment and operating costs of the entire project. The 330 cubic meters per hour (now upgraded to 580 cubic meters per hour) synthetic natural gas (SNG) non-cyclic methanation pilot plant built by China Coal Longhua using a new process underwent a 72-hour on-site calibration by experts organized by the China Petroleum and Chemical Industry Federation from October 24 to 27 last year. The results show that the pilot plant was able to operate continuously and stably, with all parameters meeting or exceeding the design specifications. Continuous methanation without recycling was achieved, along with graded control of the hydrocarbon ratio; the product contained >95% CH4, <2% H2, and no CO was detected. On November 23 of the same year, the technical achievements of this process were evaluated by an appraisal committee organized by the China Petroleum and Chemical Industry Federation, with Jin Yong, an academician of the Chinese Academy of Engineering, serving as its chairman. The expert panel members unanimously agreed that this achievement is highly innovative and possesses independent intellectual property rights ； It saves on the investment in rotary compressors as well as the associated energy consumption, resulting in significant energy savings; its overall technical level is at the international advanced stage. According to Wang Qinya, this new process is now being used in several projects for producing synthetic natural gas (using coke oven gas, pyrolysis gas, or calcium carbide furnace exhaust as raw materials), including those at the Inner Mongolia Port with a capacity of 100 million Nm3 per year, the Inner Mongolia Wuhai plant with a capacity of 300 million Nm3 per year, and the Xinjiang Shengwo plant with a capacity of 400 million Nm3 per year ； The preparation of the 1.3 billion cubic meters/year SNG process package has been completed.