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The technical improvement project involving the installation of air guns and pulse vibrators in the coal bin of Yunnan Dawa Ammonia Production’s #5 boiler has been put into operation. Author/Source: Yunnan Dawa Ammonia Production Co., Ltd. Date: 2023-03-03. Clicks: 12. Recently, the technological innovation project aimed at installing air guns and pulse vibrators in the coal bin of the #5 boiler, led by the ammonia synthesis production center at Yunnan Dawa Ammonia Production, was officially launched. This project successfully resolved the problem caused by coal accumulation in the coal bin, which affected the boiler’s ability to handle normal load levels; it also prevented the safety risks associated with operators having to manually clear blockages from heights. In the past, coal hoppers often experienced interruptions in coal supply due to high moisture content in the coal, arching caused by accumulation of coal inside the hopper. Once such interruptions occurred, manual cleaning was required to remove the blockages, which not only posed safety risks but also affected the normal operation of the boiler. Faced with this tricky problem, the center started by figuring out the reasons behind the accumulation of coal in the silo. It brought in technical experts to understand the principles of coal flow within the silo, and decided to address the issues of coal accumulation, blockages, and sticking to the silo walls by installing air cannons and pulse vibrators in the silo, thereby ensuring the continuity of the production process. This renovation project involves installing 8 FQ-C-700 pulse impact devices on the original coal bin, using a layered, symmetrical layout with a spiral upward arrangement to increase the impact area of both the pulse impact devices and the jet-type coal dispersers, thereby completely resolving issues such as coal blockage, coal accumulation, and coal sticking to the walls in the coal bin. After more than ten days of trial operation with good results, it has now been put into formal use following another round of system tuning by the manufacturer. Compared with the original manual clogging removal method, the most obvious feature of the upgraded system is **shorter time required to deal with coal blockages and reduced labor needs. In the past, when there was severe coal accumulation in the silo, 2-3 men had to climb up more than 3 meters high and use hammers to break up the coal for over an hour; sometimes their hands would get blisters from the vibration. Now, however, a woman only needs to press the button for the air cannon or the shaking device, and it takes at most 10 minutes for the coal to fall out of the silo. **It relieves the stress on workers on the production front line, reduces their workload, handles coal bridge formation in silos efficiently, eliminates coal accumulation on silo walls, eliminates the need for manual cleaning tasks, and reduces safety risks such as falls from heights. Don’t underestimate these few minutes of reduction; they play a crucial role in the operation of the boiler system. Due to the reverse flow of flue gas, in the past, when there was a disruption in coal supply to the feeder, it was necessary to adjust the air volume in order to maintain a negative pressure in the furnace at around -1000 Pa, thereby ensuring the safety of the personnel responsible for clearing blockages as well as the equipment. Especially now, with Boiler No. 5 operating at a high load of 190 t/h, adjusting the air volume in case of a coal supply disruption would result in a reduction in the boiler’s output by 10–15 t/h. At the same time, maintaining a negative pressure in the boiler for an extended period can also lead to issues such as substandard quality of the fly ash and carbon residue in the boiler, reduced efficiency of electrostatic precipitators, and liquid contamination in the flue gas from the desulfurization units. After the modification, it is no longer necessary to apply negative pressure when there is a interruption in coal supply to the feeder for a short period of time; this reduces fluctuations in the boiler load, lowers fuel consumption, ensures effective desulfurization efficiency, and helps the company achieve its goal of ultra-low flue gas emissions. In particular, given the continuous rise in the market prices of fuel coal in recent years, the renovation of the coal silos has improved the system’s tolerance to the use of slurry coal and low-quality coal. This enables better cost control while maintaining stable operations, thus helping the company reduce costs and increase efficiency. The commissioning of this renovation project fully demonstrates the center’s consistent commitment to the company’s strategic goals in terms of technological innovation, as well as its ongoing efforts to enhance employees’ theoretical knowledge in science and technology and their ability to innovate technically. Next, the center will continue to rely on technological innovation as a driving force; it will install air cannons in the upper part of the coal bins at its respective positions, and apply this technical improvement to boilers No. 1 to No. 4.