Notes on the Maintenance Work for the Second Phase Project of Lunan Chemical’s Polyoxymethylene Division

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Notes on the Maintenance Work for the Second Phase of Lunan Chemical’s Polyoxymethylene Production Unit / Author/Source: Lunan Chemical / Date: 2022-06-04 / Views: 15 On May 7, the formaldehyde catalyst and the trays in the polyoxymethylene tripolymerization distillation tower in the second phase of the production unit were identified as key items requiring thorough maintenance; at that time, there were only 20 days left before a shutdown for maintenance of the entire company’s systems. Due to the pandemic, the formaldehyde catalyst replaced during this major repair was left in a warehouse in Shanghai’s free trade zone. Yang Bin, General Manager of the Polyoxymethylene Business Unit, is constantly keeping an eye on the situation regarding the epidemic in Shanghai. On May 7th, as the situation there improved, Yang Bin immediately took four action steps: he contacted the senior executives at the catalyst company’s headquarters to coordinate matters related to exporting goods from the bonded warehouse, arranged for nucleic acid tests for the personnel responsible for loading the catalysts as well as for disinfecting the vehicles, reported the situation to his respective management team, inquired about the procedures required for vehicles coming out of the highway in Shanghai, and got in touch with the personnel tasked with unloading and loading the catalysts to ensure their timely arrival at the company. On May 21st, with the strong support and coordination of the company’s leadership, the four tasks were carried out in an orderly and seamless manner, ensuring that shipment took place as soon as the payment was received. The vehicle loaded with formaldehyde catalysts was able to leave the country successfully, and it was picked up on the Mushi Expressway, allowing the formaldehyde catalysts to reach the site where repairs were to be carried out. At this point, with 4 days remaining before the system stops for maintenance, the timely arrival of the catalyst provided time to ensure the system could complete its tasks safely, efficiently, and to high standards. The replacement of the internal components of the polyoxymethylene distillation tower is another key long-term task in this maintenance effort. The production of the critical components, namely the trays, involves specific time constraints from the bidding stage to the announcement of results and then to actual manufacturing; if these components are not delivered on time, it will significantly affect the schedule for system maintenance. Moreover, the replacement of these internal components is a crucial step in the project aimed at expanding the production capacity of polyoxymethylene. Li Zhiyuan, a member of the company’s Party Committee and executive vice general manager, was extremely anxious; he visited the polyoxymethylene business unit on multiple occasions to oversee operations in person, emphasizing the need to closely monitor the progress of the tower processes and assigning dedicated personnel to keep an eye on them. As soon as the bidding process was completed, the division notified the winning bidder to overcome the challenges posed by the pandemic and staffing shortages and to start preparing the goods immediately. The company that manufactures the internal components also cooperated actively, committing to devote all its resources to producing these components on a 24-hour basis. On May 28, Lu Heng, a technician from the department, went to the manufacturer’s site to urge them to expedite delivery, ensuring that the trays were delivered to the site on time. “The two major long-term projects under this polyoxymethylene overhaul both involve work in confined spaces. A total of 30 trays need to be replaced in the trioxane distillation tower. This maintenance work is not merely a matter of replacement; it also involves technical upgrades to the internal components as part of the project aimed at increasing the production capacity of polyoxane. The two formaldehyde oxidizers, which are the key equipment for the formaldehyde catalyst, contain a total of 42,000 tubes; it is necessary to remove the old catalyst from these tubes, clean them, and then refill them with catalyst. Through the manhole of the formaldehyde oxidizer, one can see a crowded space filled with maintenance workers who are sitting, standing, or crouching, working against time to remove the old catalyst from each tube and clean them; their organized efforts ensure that the work is carried out efficiently without chaos. Outside the manhole, supervisor Nie Dezhi wore a yellow vest and carried a registration book as well as alarm detection equipment; he ensured that analyses were conducted every two hours. Another supervisor, Gao Xiaojing, kept a close eye on those inside the oxidizer, keeping track of anyone who entered or left the equipment in order to provide the highest level of safety protection. By 12 a.m. on June 2, the removal of the oxidizer catalyst was successfully completed, 24 hours ahead of schedule, thereby securing time for the subsequent startup preparations. To ensure the orderly progress of maintenance activities, the Polyoxymethylene Division has set three scheduled times for maintenance tasks, with work handovers taking place at 8 a.m. every day. At 16:30 every afternoon, a meeting is held with the persons in charge of the construction projects and those in charge of maintenance tasks to oversee the progress of the maintenance work for that day, coordinate personnel and maintenance equipment. Those who are unable to complete their tasks on time will voluntarily work extra hours to finish them, ensuring that everything is completed by the end of the day. To gain more time, all maintenance personnel in the department voluntarily left work at 9 p.m. They reviewed the progress of the major repairs, systematically restored the equipment and pipelines that had been repaired, cleaned the filters, and checked the safety accessories, all in order to prepare for the system’s operation. Currently, the oxidizer is undergoing catalyst loading. The old trays of the polyoxymethylene distillation tower have been removed after 24 hours of continuous operation, and the upgrading work for the trays of this distillation tower is about to begin.