Experimental Studies Of Pneumatic Powder Feeding

Powder feeding device is one of the most pivotal powder handling equipments. In coal-fired power plants, the discontinuous supply of coal or powder will do great harm to the powder feeding equipment.In order to ensure the safty of boilers and other equipments, the powder feeding should be continuous and uniform. In pneumatic conveying systems, the powder feeding device should work continuously to supply high concentration powder with high conveying efficiency. In powder separating systems, powder feeding device to provide powder uniformly and stable is also required. The author designs and builds a pneumatic powder feeding device, which can provide high concentration powder continuously and uniformly.Three powders are used to perform the experiments to investigate the effects of various factors. The main work of this paper aer summarized as follows:The current technology of powder feeding is analysed and evaluatedThe effect of powder properties, such as particle size, particle density, particle shape, on the pneumatic powder feeding device performance is discussed. The properties of three powders,i.e.coal-fired fly ash, quartz sand and glass beads are tested.Base on the calculation and analysis, designs and builds a new type of pneumatic powder feeding device, which includes two parts, i.e. pneumatic conveyor and gas-solid separator. In order to reduce energy consumption, local fluidization delivery technology is selected to supply power and the bag filter is chose to complete the gas-solid separation.The powder feeding performance is tested under different operating conditions for various pneumatic architecture and find the influence of experimental factors.The orthogonal experiments of the pneumatic powder feeding with three different materials are accomplished and the optimal structure parameters and operating conditions are achieved.The experimental results indicate that the structure and operation parameters of the pneumatic powder feeding device have the influnce on the energy consumption,the uniformity and the efficiency of powder feeding. The pneumatic powder feeding device desighed in this paper have good performance and achieve the expected requirements.Finally, the research work of the whole thesis is summarized and further optimization studies of pneumatic powder feeding device are envisaged.