Rotary kiln coal-powder conveying parameters are typically determined based on the burner's specifications. In addition to serving as primary air to assist combustion, the most critical function of the coal-air mixture is to stably deliver coal powder to the burner. The air velocity at the burner outlet is fixed during the design phase, which means that the air velocity and pressure within the conveying pipeline have no direct impact on the efficiency of coal-powder combustion—as long as pulsations can be effectively avoided. This is precisely why we now discuss the coal-powder conveying parameters specific to the kiln-head burner.     

Generally, the parameters of pulverized coal in the conveying pipeline fall within a rough range, with the required air velocity being no less than 25m/s , generally according to 28m/s Calculation, coal powder Delivery Concentration For 3-5kg/m3 However, with the introduction of energy-saving and low-nitrogen technologies, reducing coal air volume and increasing pulverized coal conveying concentration have become widespread trends.     

At that time, our kiln system was equipped with Pilad burners. After many years of use, the burner heads had deteriorated, leading to poor performance and affecting the quality of the clinker. f-cao Control was less than ideal. This led to the idea of replacing the burner—with the domestically designed high-thrust burner that was being used at the time. We could determine the parameters of the pulverized coal delivery pipeline (by calculating based on fan airflow, pipe diameter, and coal feed rate). At that moment, the pulverized coal concentration in the pipeline was estimated to be around 7kg/m3 , wind speed at 30m/s The manufacturer designed it this way to reduce the proportion of primary air, thereby lowering coal consumption and nitrogen oxide emissions. They also increased the concentration of pulverized coal being transported. According to the manufacturer's tests, the maximum pulverized coal transport concentration can reach 8kg/m3 "Based on the design, we replaced the fan and the pulverized coal delivery pipeline, and after properly installing the burner and initiating ignition, we discovered an issue. Specifically, the coal delivery pressure at the kiln head is approximately..." 45Kpa , head coal plus 4 Ton / Coal delivery from the coal scale occasionally stops within hours (suddenly registering as 0 , half a minute later, material is fed again), the coal powder scale's feed rate drops below 4 Currently, the feeding process is continuous and running smoothly. Of course, as the amount of raw coal increases, the pressure in the raw coal conveying pipeline also rises. After discussion on this situation, we concluded that the excessive pressure in the pipeline is causing poor sealing and air-lock performance in the coal powder scale, leading to a buildup of large amounts of gas. As a result, the coal powder fails to flow downward. Once the gas accumulates too much, it can suddenly trigger a material collapse, creating a repetitive cycle. According to the design parameters of the coal scale, it can safely handle up to 40-60Kpa However, due to the coal powder scale having been in operation for many years, its sealing performance had deteriorated, leaving it unable to withstand the pressure. As a result, we had no choice but to halt operations and implement improvements. At that time, we connected a duct directly from the outlet of the Roots blower to the outlet of the coal powder scale, effectively reducing the internal pressure within the scale—and this finally resolved the issue.

Address: No. 118, Fengqing Road, Jinshui District, Zhengzhou City
Tel:+86-371-60960056
Mobile:+8613849187223
Email:zhongweigongyelu@126.com