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Zhongxin Chemical’s synthetic catalysts have enabled the production of 400,000 tons of crude methanol in total. Author/Source: Zhongxin Chemical. Date: July 7, 2022. Clicks: 14. As of 8:00 on July 5, the synthetic catalysts used in Zhongxin Chemical’s plant with an annual capacity of 300,000 tons of methanol had been in operation for a total of 7,895 hours and 329 days. The average hourly production volume was 51.6 tons, with a space-time yield of 1.09 T/m3·h and a one-pass conversion rate of 71%. A total of 402,800 tons of crude methanol have been produced, setting a new record since the plant began operations; currently, the plant is operating well. The catalyst used in this furnace of the methanol synthesis unit is of the XNC-98-5 type developed by the Southwest Chemical Research Institute. Since operations began on April 8, 2021, the technical team has maintained close communication with the manufacturer, drawing on experience and identifying areas for improvement. With safe production as the top priority, and taking into account the high-load and high-intensity operating conditions of this facility, the production scheduling center took the lead, with coordination from various branch plants, to develop a series of measures aimed at increasing output while reducing costs. One such measure was to improve the methanol load rate; by exchanging information with sister companies such as Jinmei Zhongneng, Anhui Haoyuan, and Jinmei Huayu, and by considering the current operating conditions of the methanol plant, the temperature control parameters for the synthesis towers were optimized, thereby unlocking the catalyst’s potential to achieve higher production levels. As a result, a record monthly output of 39,903 tons of crude alcohol was achieved. Second, strict temperature control measures should be established to maximize the active period at the corresponding temperature. Currently, the temperature difference between the methanol synthesis drum and the outlet of the synthesis tower is 8°C. The pressure in the drum as well as the temperature of the catalyst bed meet the requirements of the current load. In the future, after a comprehensive analysis based on indicators such as the overall production capacity, CO conversion rate, output, and system pressure, the drum pressure setting will be increased cautiously in order to maximize the efficiency of the catalyst. Third, strictly control the total sulfur level in the purified gas to reduce the risk of catalyst sulfidation and deactivation. Excessive total sulfur content in the gas purified by low-temperature methanol washing directly affects the yield of methanol and the service life of the synthesis catalysts, thereby severely impacting the stable operation of the methanol plant. By taking into account the current operating conditions of the plant, and through a detailed analysis of the factors that cause excessive total sulfur content in the purified gas, appropriate countermeasures are proposed to keep this content below 0.1 ppm, which significantly enhances the safe, stable, and long-term operation of the plant. Fourthly, to address the bottleneck of methanol plants not being able to operate at full capacity during the summer months over the years, efforts have been accelerated to carry out technical upgrades to the circulating water system in the east tower. At the same time, low-temperature domestic water is used to supply the cooling required by the ammonia refrigeration system, keeping the CO2 concentration around 4%, thereby meeting the demands for high-capacity operation of methanol synthesis during the summer.