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The Methanol Division of Zhongyuan Dahuahua held a meeting on the energy-saving renovation of the CO2 control system. Author/Source: Zhongyuan Dahuahua. Date: 2022-03-03. Clicks: 12. On March 1st, the Methanol Division held such a meeting, during which progress on the energy-saving renovation of the CO2 control system, the performance of the system after implementation, the benefits achieved, and existing problems were discussed. ECT’s technical staff, company leader Zhang Hongjie, and compression unit expert Bai Jinguang attended the meeting. In previous operations, the anti-surge valves of the C02 unit suffered from issues such as high opening degrees and high energy consumption. Adhering to the principles of striving for excellence and reducing energy use, the Methanol Division, through thorough research and discussions by relevant technical staff, took advantage of the coal chemical plant’s maintenance period in 2021 to install a new ECT system. This improved the performance of the controllers and enhanced the stability of the system, ensuring the healthy and stable operation of the unit’s \"brain\". During operation, the ECT control system sets the accuracy of CO2 compressor inlet pressure regulation at 1 KPa, ensuring the stable operation of the unit as well as rapid adjustment. During this optimization process, based on the feedback regarding the system’s performance after it had been in operation for a period of time, as well as the need for more precise control, the accuracy of the adjustment at the inlet of the CO2 compressor was changed to 0.1 KPa. This not only enables the ECT system to utilize its precise control capabilities to the fullest extent, but also improves the accuracy of process control, providing a more precise technical basis for reducing the energy consumption of the unit during operation. After optimization, the response speed and accuracy of the unit inlet pressure control loop were also significantly improved, creating the conditions for further optimizing the unit inlet pressure control. After adjusting and testing the set value for the inlet pressure, it was changed from 20 KPA to 24 KPA; this still ensured stable backpressure in the upstream methanol plant, preventing overpressure, and effectively reduced the speed of the unit. The PID parameters of the export vent valve are finely tuned to improve the accuracy and response speed of control, ensuring stable pressure at the fourth stage outlet of the compressor and thus maintaining stable operation of the entire unit. At the same time, even when the rotational speed decreases, it is still possible to ensure a stable and sufficient supply of gas for the gasification unit downstream of the CO2 compressor. Preliminary calculations show that under normal operating conditions, steam consumption can be reduced by approximately 2.2 tons per hour. The holding of this special meeting not only provided a comprehensive overview of the technical approaches and solutions for the energy-saving renovation of C02 control systems, but also greatly boosted morale at a critical time for addressing the sources of losses. All employees of the Methanol Division will make every effort to reduce energy consumption and waste, identify additional shortcomings and weaknesses, strive to improve productivity, and contribute more to the company’s reform and development.