Successful commissioning of China's single plant for producing ethylene glycol from syngas with maximum efficiency
On November 28, 2018, China independently developed ldquo; China's single largest high-efficiency synthesis gas ethylene glycol plant successfully put into operation - rdquo; a press conference was held in Beijing. Recently, developed by Ningbo Zhongke Far East Catalytic Engineering Technology Co., Ltd. (hereinafter referred to as Zhongke Far East), Shandong Hualu Hengsheng Chemical Co., Ltd. has opened up the whole process of a large-scale ethylene glycol plant with an annual output of 500,000 tons. At present, it has been running safely and steadily for nearly two months, the load of the plant reaches 100%, and the rate of excellent products reaches 100%. This marks a new breakthrough in key technologies of modern coal chemical industry in China, and the self-developed technology of syngas to ethylene glycol ranks among the world's leading ones.
Gu Zongqin, President of the Planning Institute of Petroleum and Chemical Industry, Jingan, former President of China Coking Industry Association, Cui Xuejun, President of China Chemical Newspaper, and other leaders, from the Ministry of Industry and Information Technology, the Coal Chemical Committee of China Petrochemical Federation, industry associations, representatives of relevant enterprises, as well as CCTV network, Central People's Radio, Science and Technology Daily, Sinicization. Nearly 100 journalists from the news media, such as the Labor Daily and Sinochem New Network, attended the conference.
It is understood that Hualu Hengsheng's large-scale ethylene glycol plant with an annual output of 500,000 tons, which combines the research and development achievements of Zhongke Far East for ten years, will start construction at the end of 2016. After nearly two years of construction, the main unit was completed in September, and materials were delivered on September 30. On October 1, the whole system process was opened, and a successful start-up was achieved. On October 2, the unit's production load was up to 50%. On November 13, the unit load reached 100%, the daily output reached 1490 tons, approaching the design value of 1500 tons, and the rate of excellent products reached 100%.
Zhao Bai, Director of Far East Market, said at the launch meeting that the successful start-up of the device had created many records: the shortest start-up time of the ethylene glycol plant; the products reached 100% excellent products; in a real sense, the large-scale ethylene glycol plant was realized; all the equipment was localized; and the unit investment of the plant was the lowest. As the first large-scale demonstration project of 500,000 tons of ethylene glycol in China, it has been developed and put into operation on the basis of no domestic precedent to follow. It can reach 100% full load quickly in one and a half months, and the plant runs steadily and the product quality is excellent. It proves that the technology of producing ethylene glycol from Zhongke Far East syngas is mature, reliable and has good performance.

Top left: Zhao Bai, Director of Far East Market; Top right: Li Tong, Ph.D., Ningbo Institute of Materials, Chinese Academy of Sciences;
Left: Vice-President Wang Yunsheng of China Chengda Engineering Co., Ltd; Right: Vice-President Gao Lan of Hualu Hengsheng Engineering Co., Ltd.
Gao Lan, Deputy Engineer of Hualu Hengsheng Sheng, said that the construction of 500,000 tons of ethylene glycol plant was a major decision-making and action of the company. With the tacit cooperation and efforts of all parties, the construction task of quality and quantity was completed on schedule. The successful completion and commissioning of the plant was a major milestone in the history of Hualu Hengsheng Sheng.
Wang Yunsheng, deputy vice president of Chengda Engineering Co., Ltd. of China, said that the device faced three major technical challenges: the largest single unit, super-large equipment and large diameter thin-walled pipe. In the whole process of project design, construction, commissioning and commissioning, through the joint efforts of all parties, we have achieved remarkable achievements such as successful start-up, shortest production time, excellent product quality, large-scale key equipment process, nationalization of all equipment and materials, and investment saving.
At present, there are three main processes for the preparation of ethylene glycol from coal: one is the direct synthesis of syngas from coal gasification, and the other is the one-step direct synthesis of ethylene glycol from syngas. The second is olefin process, using coal as raw material, syngas is obtained by gasification, transformation and purification, ethylene is obtained by methanol to olefin, ethylene epoxidation, ethylene oxide hydration and product refinement, and finally ethylene glycol is obtained. Thirdly, oxalate process, which takes coal as raw material, obtains carbon monoxide and hydrogen separately through gasification, transformation, purification and purification. Carbon monoxide is synthesized by catalytic coupling and refined to produce oxalate, then hydrogenated with hydrogen and refined to obtain ethylene glycol.
According to Li Tong, Ph.D., Ningbo Institute of Materials, Ningbo Zhongke Far East Catalytic Engineering Co., Ltd. has been carrying out the research work of catalytic coupling of carbon monoxide to oxalate and hydrogenation of oxalate to ethylene glycol since 2009. In 2011, the Engineering Technology Research Center was set up with Ningbo Material Institute of Chinese Academy of Sciences, and a core technical team was set up. The technology of syngas to ethylene glycol was developed on the platform of the national public testing center of Ningbo Material Institute of Chinese Academy of Sciences. After nearly ten years of continuous research, many new coal chemical technologies with independent intellectual property rights have been obtained. The technology of syngas to ethylene glycol has been industrialized in domestic plants and has been highly recognized by the industry. The key catalyst for syngas to ethylene glycol was successfully developed in 2013.
Compared with the traditional oxalate process, the technology of preparing ethylene glycol from Zhongke Far East syngas has unique advantages in coupling catalyst, hydrogenation catalyst, reactor and by-product formation. By designing eggshell-type distribution catalyst, the active component palladium is evenly distributed on the surface of catalyst particles. On the one hand, it effectively reduces the diffusion distance of reactants in the catalyst channel, increases the reaction activity, on the other hand, it improves the utilization ratio of precious metals and effectively reduces the amount of precious metals. For hydrogenation catalysts, layered copper silicate material is used as catalyst, which can reduce to a controllable ratio of cuprous oxide to zero valent copper, and has good chemical stability and thermal stability. In the development of process packages, the time-space yield of products can be improved by developing efficient catalysts; the gas distributor of new reactors is designed to improve the distribution of reaction gases; the heat and mass transfer form of reactors is optimized to improve the heat transfer efficiency; thus the reactor can be large-scale, the productivity of single equipment can be increased and the investment of units can be reduced. In order to improve the yield of high-grade ethylene glycol, by developing highly selective hydrogenation catalysts to reduce by-product generation, chemical reactions were designed to transform and separate difficult-to-separate impurities, special internals and fillers for ethylene glycol distillation column were developed, and technical schemes such as rational distillation sequence avoiding ethylene glycol polymerization were designed to reduce distillation energy consumption. To improve the yield of high-grade ethylene glycol.
Based on the advantages of Zhongke Far East Ethylene Glycol technology, Hualu Hengsheng cooperated with Ningbo Zhongke Far East Catalytic Engineering Co., Ltd. to optimize and transform 50,000 tons of ethylene glycol industrial plant, in which all carbonylation and hydrogenation catalysts were replaced by Zhongke Far East products. The production load reached 100% in May 2015, and the device operated steadily.The production cost is low, the product quality reaches the grade of polyester, and the excellent product rate reaches 100%, all of which are used in the polyester industry. In July 2016, COSCO Far East and Hualu Hengsheng signed a technical contract of 500,000 tons of ethylene glycol, and took the lead in building the largest scale production plant of coal-based ethylene glycol in China. Based on the operation of the 50,000 ton unit, a series of optimizations have been carried out. DMC separation, nitric acid reduction, distillation and thermal coupling technologies have been adopted. The energy consumption and material consumption of the unit are in the leading level in the same industry, and the cost advantage is obvious.
Gu Zongqin pointed out that high-quality development is a new subject for every industry. Hualu Hengsheng 500,000 tons/year synthesis gas ethylene glycol plant is the result of cooperation and joint breakthroughs, which fully reflects the characteristics of high-quality development. The project has the following characteristics: large scale, high technical difficulty, low investment cost, fast construction speed and good economic benefits. He believes that this technology is a new breakthrough in the coal-based ethylene glycol industry, an innovative achievement and inspiring.
The data show that ethylene glycol is mainly used to make polyester polyester, polyester resin and so on, and has a wide range of uses. As the largest polyester producer and seller in the world, China is also the largest consumer of ethylene glycol in the world. However, due to the limitation of petrochemical raw materials, the growth rate of ethylene glycol production in China is limited. Experts at the meeting said that under the background of rich coal and lack of oil and gas, the development of large-scale technology of coal-to-ethylene glycol can meet the self-sufficiency of ethylene glycol in China, fill the huge gap in the domestic market, and then drive the development of downstream polyester industry. This not only opens up a new way for the clean and efficient utilization of coal, but also effectively guarantees the national energy security and energy structure optimization.
New technologies will strongly promote the development of high-end ethylene glycol in China. Looking forward to the future, Zhao Bai, Director of Far East Market, said that COSCO Far East intends to enter the capital market and become an international first-class catalytic engineering technology research and development company.