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Yueneng Chemical has been operating stably for over 20 days~Significant progress in addressing reactor fouling in the LDPE/EVA unit Author/Source: Yueneng Chemical Date: 2021-04-29 Clicks: 9 After more than a month of efforts including technical management, identification of potential hazards, staff training, process optimization, improvement in inspection quality, and special care for key equipment, Yueneng Chemical’s LDPE/EVA unit has made breakthrough progress in overcoming the problem of reactor fouling. The feed rate to the unit has increased significantly, and it has been operating stably for over 20 days, with excellent performance. It is reported that fouling of the reactor walls not only leads to a decrease in the reactor’s conversion rate, a significant drop in load, increased consumption per unit of product, and unstable product quality, but it also raises the risk of overheating and decomposition of the reactor, as well as even \"explosive polymerization\". Faced with such a tough challenge, the technical managers of LDPE/EVA plants came up with ideas and strategies, consulted a large amount of information from patent holders, and proactively engaged in discussions with these patent holders as well as similar domestic plants to address the issues. Multiple meetings were held to explore solutions for removing adhered material from the walls, and it was ultimately decided to use an \"on-line treatment\" approach. After the plan was finalized, the technical supervisors of the device tried every possible method, such as adjusting the amount of propionaldehyde injected, the temperature and flow rate of hot water, as well as the parameters of the pulse valve, in order to narrow the distribution of polymer melt indices in reaction zones 1 to 4, increase the melt index in the reaction zones with lower melt indices, prevent the formation of polymers with high molecular weights, and maintain a certain rate of chain transfer within the reactor. As a result of two weeks of steady operation, the problem of sticking to the reactor walls improved significantly. To maintain the hard-earned effect of preventing sticking to walls, this system first encourages employees to improve the quality of their inspections, with the goal that \"everyone checks for potential hazards and monitors them at all times\"” ； Secondly, make use of the one and a half hours available after the end of the daily day shift and before the start of the night shift for intensive training, in order to improve employees’ operational skills and theoretical knowledge ； Third, strengthen operation and management by optimizing certain operational steps to make them more rational and safe ； Fourth, we continue to carry out special maintenance on key equipment. In particular, we constantly monitor the operating status and parameters of the booster/primary machine and the two Lürer hot water pumps; any abnormalities are promptly addressed through timely adjustments. After two consecutive weeks of monitoring, the treatment of fouling on the reactor walls proved effective, and the plant operated smoothly. Next, the facility will actively prepare for the work related to the production of ethylene-vinyl acetate (EVA) copolymers.