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Successful renovation of the boiler flame detection cooling air system at Yangmei Guotai Xinhua Power Division Author/Source: Yangmei Guotai Xinhua Date: 2020-08-19 Clicks: 17 At 17:50 on the afternoon of August 14, as the operators gradually adjusted the primary air pressure of Boiler No. 2, the pressure dropped below 5.5 KPa; immediately thereafter, the A flame detection fan started up, and the pressure rose back to 8.2 KPa. This marked a complete success in the renovation process involving the integration of the boiler flame detection cooling air system with the primary air system. As an important auxiliary system in the boiler system, the flame detection cooling air is used primarily to cool the flame detection probes of the burners, thereby preventing them from being damaged. Flame detection protection is one of the key protection systems for boilers. When both flame detection cooling fans stop operating, or when the air pressure drops to a certain level and cannot be restored, it will trigger the boiler’s main protection mechanism, MFT, thereby shutting down the furnace and stopping the unit from operating. Therefore, it is extremely important to ensure the reliable operation of the flame detection cooling wind system. Due to the thin blades of the two flame detection fans as well as their weak base frames, problems such as excessive vibration and high motor temperatures often occur during operation, leading to frequent repairs. This not only increases maintenance costs and labor requirements but, more importantly, it poses a risk of the boiler equipment triggering an MFT shutdown when a single fan is in operation, thereby causing unplanned shutdowns of the unit. There have been instances in domestic power plants where such situations have resulted in unnecessary economic losses. To completely resolve this issue, the Power Division organized technical efforts to find a solution. By analyzing the actual conditions on site together with mechanical and thermal control technicians, and by drawing on the improvement experiences of similar power plants, thorough discussions and evaluations were conducted. Ultimately, a technical modification plan was devised to integrate the boiler’s flame detection cooling air into the primary cold air system. By analyzing the actual operation data of the primary fans, it was determined that the boiler’s primary air system had high reliability and sufficient margin, with all parameters meeting the requirements of the flame detection cooling air system. During normal operation, the primary cold air served as the main air source to cool the flame detection probes; when the primary air supply stopped or the air pressure decreased, the flame detection cooling fans would start up automatically to continue cooling the probes. The existing two flame detection cooling fans, combined with the primary air cooling system, made the overall system even more reliable. Through optimization and modification, not only has the safety and reliability of the boiler flame detection cooling air system been improved, but electricity consumption can also be reduced by 120,000 KWh per year. In recent years, the Power Division has consistently encouraged technological innovation and improvement. In response to the technical challenges encountered in safe production processes, it has motivated employees to be innovative and proactive in their efforts, fostering an atmosphere of innovation among all staff. By leveraging the creativity and skills of front-line employees, the division has provided strong support for improving the quality and efficiency of the company’s operations, achieving tangible results as a result. By the end of July, a number of technical upgrades and innovations had been implemented, resulting in annual reward payments totaling 10,700 yuan, thus truly achieving \"using small efforts to generate significant benefits\".