PX production from coal tar – a new route to coal-derived aromatics

Thread Content

PX production from coal tar – a new pathway for coal-based aromatics. The production of aromatics from coal-derived methanol is considered the mainstream process for coal-based aromatics (CTA). In 2013, Huadian and Tsinghua University jointly developed a pilot plant with a capacity of 10,000 tons per year for the production of aromatics from fluidized-bed methanol (FMTA) in Yulin, Shaanxi； In 2014, the process package for FMTA’s 600,000 tons per year demonstration plant was approved. HuanDian Group has entered into a strategic partnership with TianLong Group and Shaanxi Yitai Energy to build a million-ton-scale project for the production of aromatics from coal-based methanol in Yulin, Shaanxi. Meanwhile, the combined effect of the market environment and technological advancements has made the production of aromatics from coal tar economically and technically feasible. In addition to coal-based methanol for aromatic production, PX production from coal tar will become a new route for coal-derived aromatics. One of the main uses of coal tar in our country at present is as a raw material for processing by local refining enterprises, or for hydroprocessing to produce light fuel oils. This year, our country has granted local refineries the right to import crude oil as well as the authority to import such oil. At the beginning of August 2015, Dongying Yatong Petrochemical Co., Ltd. was approved to use a quota of 3.36 million tons per year of imported crude oil; it became the sixth local refinery to receive this right, following Dongming Petrochemical, Panjin Beiran, Sinochem Hongrun, Lijin Petrochemical, and Kenli Petrochemical. Yahua Consulting predicts that the demand for coal tar by local refineries will decrease by over 20 million tons in the future, allowing sufficient raw material supply for the production of aromatics from coal tar. The sharp decline in international oil prices since the second half of 2014 has also dragged down the prices of gasoline, diesel, and fuel oil in China. The reduced operating rate of plants that use coal tar hydrogenation to produce light hydrocarbons has contributed to low prices for coal tar in the market. In the first half of 2015, the average market price of coal tar in China was below 2,000 yuan per ton (including taxes). Yahua Consulting believes that changes in the market environment have led to an ample supply of coal tar in China at low prices, making the profitability of producing aromatics from coal tar promising. Technologically, the maturity of advanced hydrocracking technology and light hydrocarbon aromatization technology has made PX production from coal tar feasible. Advanced hydrocracking technology can use full-range coal tar (including tar pitch) as raw material to primarily produce heavy naphtha as feed for aromatic complex units. A light hydrocarbon aromatization unit can use light naphtha, aromatic extract oil, liquefied gas, reformate C5, and other materials from coal tar-based aromatic compound production plants as feedstocks for the aromatization process, thereby producing aromatics and propane and maximizing the yield of aromatics in coal tar-based PX production units.