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World’s first suspended-bed high-pressure coal tar hydrogenation project sets new operation record; Author/Source: Coal Chemical Engineering 114 Forum; Date: 2020-08-23; Clicks: 11. As of 6 a.m. on August 21, Project 712 at Anyuan Company had been operating stably for 73 days. During this period, a total of 62,900 tons of coal tar, 8,200 tons of light wax oil, 34,600 tons of heavy wax oil, and 4,600 tons of phenol oil were processed. The average yield for the main products was 75.31%. At present, the VCC unit is operating smoothly; the processing load on the two-stage suspension bed exceeds 80%, and all parameters meet the technical requirements. The trial operation achieved the desired results, laying a solid foundation for achieving full production capacity and efficiency throughout the year. This has enabled the unit to maintain a stable operating load along with a product yield of 80% in both cases. This achievement reflects the attention and expectations of everyone within the group, as well as the hard work and dedication of the employees of Anyuan Company. This device utilizes advanced hydrogenation technology to produce high-quality light paraffin oils and heavy paraffin oils using coal tar as a substitute for petroleum resources. This is the world’s first full-range high-temperature, high-pressure slurry bed hydrogenation process, featuring high technical complexity, a complicated process flow, and significant operational difficulties. Furthermore, since there is no existing experience to draw on during the operation process, the parameters must be adjusted through trial and error, **which increases the uncertainty in the operation. In the face of various technical challenges, Anyuan Company has attached great importance to these issues. With strong support from the group and Yulin Coal Chemical Company, the company has continuously drawn on the experience gained from previous trials, conducted comprehensive analyses of the problems and weaknesses associated with the coordinated operation of various units, and established a number of management measures, including quality standards for crude oil entering the plant, plans for dehydrating coal tar and extracting phenols, guidelines for the operation of the wastewater treatment system, and procedures for using red mud catalysts in the VCC unit. Through multiple long-term operations of the plant and discussions with design institutes and experts, technical upgrades were successfully carried out on devices such as the VCC unit’s heating furnace, membrane separation system, dry gas desulfurization unit, acidic water stripping unit, and wastewater treatment system. These upgrades helped overcome the bottlenecks and challenges associated with the plant’s operation, and the process parameters for its operation were optimized. A technical approach that fully meets the requirements of the VCC process was developed, laying a solid technical foundation for the optimization of the process package and the industrialization of the VCC project. To date, the unit has been operating smoothly, continuously setting new performance records. In the next phase, Anyuan Company will gradually increase the VCC processing load of the unit to 90%. While ensuring its stable operation, measures such as reducing the daily natural gas consumption, introducing a liquid sulfur feeding system to replace DMDS, and further optimizing the reaction depth will be taken to fully pursue efforts to reduce costs and improve efficiency. It is understood that the suspended-bed full-distillate coal tar hydrogenation unit, as one of the advanced heavy oil hydrogenation processes that have been validated on an industrial scale, addresses the process deficiencies present in coal tar processing and enables the value-added utilization of heavy coal tar resources. It holds great prospects for industrial application, opening up new paths for the development of the petrochemical and coal chemical industries, and representing a significant technical breakthrough in the lightening of heavy coal tar.