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Zhongan Coal Chemical meticulously cuts costs and works together to increase efficiency. Author/Source: Zhongan Coal Chemical. Date: December 2, 2020. Click-through rate: 24. “What is the purpose of this flushing water?” Can it be stopped? What are the consequences of stopping it? What’s the load on the equipment today? Is there anything abnormal? ”This is a common question asked by managers in the methanol department to plant operators. Through communication with frontline workers, we not only gain insights into the unit’s production status, but also help plant personnel stimulate their thinking, thereby providing ideas for the stable operation of the unit and energy conservation. The Methanol Division actively responded to the initiatives aimed at improving efficiency and quality, as well as the “100-day campaign for achieving performance targets”. Thanks to the joint efforts of all managers and employees, measures such as reducing consumption of utilities have led to a total cost savings of over 6.9 million yuan ； Monthly boundary benefits are increased by 9.752 million yuan through the production of methanol (at 310 yuan per ton of methanol). Cooperation between upstream and downstream units optimizes methanol production. “Add some hydrogen to us,” “Okay, just a moment.” “Add some carbon (carbon dioxide) as well.” “Right away. Please check what the current composition is.” The hydrogen-to-carbon ratio in the methanol synthesis gas is a crucial factor in controlling both the yield and quality of methanol. Therefore, scenes like the ones described above frequently occur in the control room, where the methanol synthesis unit and the purification unit work together to ensure high-yield and high-quality methanol production. The various units within the Methanol Division have been working together proactively to optimize operations. In October, methanol production once again exceeded 180,000 tons, reaching 188,824 tons. At the same time, various units are also taking measures to increase methanol production. The purification unit increases the water-to-gas ratio at the inlet of the converter, reduces methanation side reactions, and as a result, methanol production increases by over 1.2 tons per hour after adjustment ； The methanol synthesis unit reduces purge gas emissions by monitoring, issuing alerts, and identifying sources of nitrogen. This has resulted in an increase in methanol production by approximately 1.7 t/h. Additionally, by optimizing the operating mode of the PSA unit, an extra 300 Nm³ of hydrogen is recovered per hour while maintaining the quality of the hydrogen produced; this translates to an additional methanol output of 0.13 t/h. Active efforts are being made to adjust process conditions to ensure energy conservation and consumption reduction. The continuous optimization of these conditions contributes to the stable and efficient operation of the facilities. All units within the Methanol Division are actively optimizing their process conditions to help achieve energy savings and reduced consumption. “I’ll bring some more methanol over! ”“Okay, open your valve slowly and increase the flow gradually; otherwise, the temperature in my furnace will fluctuate too much. ”This was a conversation that occurred frequently in May this year. To improve the quality of methanol with low sulfur content and enhance absorption efficiency, the purification unit replaces the methanol with high sulfur content: a portion of it is sent to the wastewater treatment unit as a carbon source for nitrifying bacteria ； A portion is sent to the sulfur recovery unit to increase the temperature of the acid gas burner and improve sulfur recovery rates. The gradual replacement with sulfur-containing methanol improves the absorption efficiency of lean methanol. During the summer, when the ambient temperature is high, the sulfur recovery unit shuts down 7 sets of sulfur tank heaters in a timely manner based on this temperature, thereby reducing the storage temperature of liquid sulfur. This results in a savings of 720 tons of low-pressure steam per month, as well as a reduction of 160 tons in the consumption of water used for the liquid sulfur shaping process per month ； The unit reduces the consumption of high-pressure steam in the acidic gas preheater, lowering the temperature of the incoming acidic gas; as a result, the unit produces 360 tons more high-pressure steam per month. Everyone works diligently to minimize operating costs. “Is this height sufficient?” ”“Move it a little lower; that position is still not very convenient for daily verification. ”This is a conversation that took place during the process of shifting the alarm device. When periodically calibrating certain alarms in the methanol section, scaffolding must be erected; each unit relocates those alarms that are difficult to inspect. While ensuring effective monitoring, the shift results in a **reduced detection time and lower safety risks, saving approximately 200,000 yuan per year. There are various forms of such beneficial rationalization modifications, such as the clever tweak to the oxygen content analyzer in sulfur recovery units. The sulfur recovery unit frequently gets clogged at the inlet of the flow guide tube of the zirconia oxygen analyzer. By installing a filter screen, the maintenance interval was extended from once every 3 days to once every 15 days, thereby reducing maintenance costs and operational risks. ““The main washing pump is operating normally, vibration levels are within normal limits, and bearing temperatures are normal,” was the message transmitted over the walkie-talkie every hour during the special maintenance of the purification unit’s main washing pump. The stable operation of equipment is crucial to the entire production process. Based on regular equipment inspections, all units within the Methanol Department have intensified their monitoring of equipment that currently has no backups or exhibits minor abnormalities. “Class leader, how about we use less circulating water in our class today? ”“I think it’s feasible. The load has been relatively stable these past couple of days, so we can reduce the amount of steam vented and produce a bit more steam instead. Let’s strive to also win first place in the labor competition this month. By the way, it’s important to first ensure that the device is stable. Don’t skimp on necessary expenses when it’s needed; otherwise, you might end up gaining little in return for a lot of effort. ”During the “Zhong’an Cup” competition for small-scale productivity metrics, teams competed with one another; while ensuring stable operations, the control room staff reduced the consumption of circulating water and steam while increasing steam production. During routine inspections, no leaks were overlooked.