Shenhua Ordos Coal-to-Oil to Build 350,000-ton Coal Liquefied Oil Residue Extraction Project

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This post was last edited by liaifeng on 2018-8-9 at 09:44. Shenhua Ordos to build a 350,000-ton/year coal liquefied oil residue extraction project. Author/Source: Date: 2017-07-11. Clicks: 27. Recently, in accordance with the relevant regulations regarding the environmental impact assessment procedures for construction projects, the Ordos Environmental Protection Bureau accepted the environmental impact report for the 350,000-ton/year coal liquefied oil residue extraction project submitted by the Ordos Coal-to-Oil Branch of China Shenhua Coal-to-Oil Chemical Co., Ltd. The acceptance status will be made public, with the publicity period running from July 6, 2017, to July 20, 2017 (10 working days). Background of project construction: Coal liquefaction residue is a mixture with high ash content, high sulfur content, and high calorific value, obtained as a result of pressure reduction and oil separation processes following the coal liquefaction reaction in direct coal liquefaction processes. It appears as a solid asphalt-like substance at room temperature. The Shenhua Ordos Coal-to-Oil Branch generates approximately 700,000 tons of such coal liquefaction residue each year. Oil residue is mainly composed of inorganic and organic components; the inorganic components include minerals in coal, unreacted coal, and iron-based catalysts, while the organic components consist of heavy oils and asphalt, with asphalt accounting for about 50% of these organic components. According to the identification results of the Institute of Solid Waste Pollution Control Technology at the Chinese Academy of Environmental Sciences regarding the hazardous properties of the residues resulting from direct coal liquefaction in companies, these oil residues do not exhibit corrosivity, reactivity, flammability, or leaching toxicity. However, 9 samples had a cumulative toxicity level that exceeded the standard limits; this figure is 6 higher than the lower threshold specified in the \"Technical Specifications for Identifying Hazardous Wastes\" (HJ/T298–2007). Therefore, such samples should be treated as hazardous waste. The current method for handling oil residues involves cooling them with water to facilitate solidification, followed by crushing them into solid fragments with a thickness of 3–5 mm. These fragments are then transported, in accordance with hazardous waste management regulations, to the company’s fully enclosed temporary storage facility for storage, where they are used as fuel for the boilers in the company’s own power plants. Coal liquefaction residue is used directly as boiler fuel and gasification feedstock without any treatment; it is merely employed as ordinary fuel, and the high value-added potential of the asphaltic substances contained in this residue is not utilized, resulting in a waste of resources. To optimize resource allocation, achieve high-value utilization of coal direct liquefaction residues, and improve the coal liquefaction product chain, Shenhua Coal-to-Oil Company plans to invest 391.2085 million yuan to build a 350,000-ton/year coal liquefaction residue extraction facility on the reserved land within its existing coal-to-oil plant. Process technology route: The production of coal liquefaction oil residue extracts in this project uses the high-temperature oil residues resulting from coal liquefaction as raw materials, and coal tar wash oil as the extraction solvent. A physical separation process is employed; taking advantage of the fact that the asphalt components in coal liquefaction oil residues are soluble in the solvent while solid components such as ash are not, the asphalt in the oil residues is mixed with the solvent at a certain temperature to achieve dissolution. Subsequently, solid-liquid separation equipment is used to carry out separation, yielding liquids with different ash contents. After the solvent is recovered through vacuum distillation, coal liquefaction asphalt products of high, medium, and low quality are obtained. These products are then cooled, shaped, packaged, and sold. After the raffinate is dried in two stages to reduce the solvent content to less than 5%, it is cooled before being used as fuel for the boiler in the on-site power plant. Main construction contents: At present, the utilization of coal liquefaction residue both domestically and internationally is still in the experimental stage. The main research processes include hydrogenation liquefaction, dry distillation (pyrolysis, coking), combustion, gasification, and extraction. The treatment technologies for coal liquefaction residue are shown in the table below. The Ordos Coal-to-Oil Branch of China Shenhua Coal-to-Oil Chemical Co., Ltd. (referred to as “Shenhua Ordos Coal-to-Oil Branch”) is affiliated with China Shenhua Coal-to-Oil Chemical Co., Ltd. It represents the world’s first commercial demonstration project that uses the direct coal liquefaction process to produce finished oil. The facility is located in the Wulamulun Industrial Zone of the Shengyuan Coal Chemical Industry Base in Ordos, specifically in Majiata area of the Shendong mining region. The total area of the plant is 3,004.12 mu, and it employs 1,700 people. In response to the strategic decision to adjust the energy structure, as well as environmental policy requirements regarding the clean conversion of coal and carbon emission reduction, the company makes full use of the coal resources available in the Shenhua mining area of the Shenfu-Dongsheng coalfield. With the strong economic and technical support provided by its parent company, it carries out coal liquefaction projects within the coal liquefaction plant complex. The construction scale of Phase 1 of this project is 3.2 million tons per year of oil products, and it consists of three production lines. To reduce investment risks and avoid the challenges that may arise during the initial industrialization process, Phase 1 is implemented in stages: one production line with a capacity of 1.08 million tons per year of oil products is built first, which is also referred to as the pilot project for direct coal liquefaction; the other two production lines are constructed only after success is achieved in this initial phase. Preliminary production began in June 2009. The main products include diesel, naphtha, gasoline, LPG, etc.