gravel bed filter

The granular layer dust collector is an internal filter dust removal device that uses granular materials (such as silica, gravel, coke, metal shavings, ceramic particles, etc.) as the packing layer. There are many types of dust collection, and the dust removal efficiency is less affected by temperature, air volume, and large fluctuations in dust. The dust filtering mechanism is similar to a bag filter, mainly relying on screening, inertial collision, interception, and diffusion to allow dust to adhere to the particle filter material and dust particle surface. The filtration efficiency increases with the thickness of the particle layer and the accumulated dust layer, and the pressure loss also increases accordingly.
The dust filtering mechanism is similar to a bag filter, mainly relying on screening, inertial collision, interception, and diffusion to allow dust to adhere to the particle filter material and dust particle surface. The filtration efficiency increases with the thickness of the particle layer and the accumulated dust layer, and the pressure loss also increases accordingly.
The granular layer dust collector has the advantages of simple structure, easy maintenance, high temperature resistance, corrosion resistance, high efficiency, small footprint, and low investment. The granular layer dust collectors used in China include tower type cyclone granular layer dust collectors and fluidized bed granular layer dust collectors. For the former, the dust containing gas is pre purified by the cyclone dust collector and introduced into the particle layer with a comb rake, so that fine dust is trapped in the gaps of the active particle layer on the surface of the packing. The thickness of the packing layer is generally 100-150mm, and quartz sand with a particle size of 2-4.5mm is commonly used as the filter material. The filtration air velocity is 30-40m/min. During dust cleaning, air is blown back into the particle layer in the opposite direction at an air velocity of 45-50mm/min to keep the particle layer in an active state. At the same time, the rotating comb and rake stir the particle layer. The blowback time is 15 minutes, the blowback cycle is 30-40 minutes, the total pressure loss is 1700-2000Pa, and the total dust removal efficiency is over 95%. The dusty airflow generated by reverse blowing is returned to the cyclone dust collector. This type of dust collector often adopts a multi cylinder structure with 3-20 cylinders arranged in a single or double row. Each single cylinder can run continuously for 1-4 hours. The boiling particle layer dust collector does not have a comb rake for dust cleaning, and the back blowing dust cleaning wind speed is relatively high (50-70m/min), which keeps the particle layer in a boiling state.