In the Soviet Union began to be used as a scrubber fans. The first installation of water supply on the impeller were obtained from the GDR. Installation of these worked in the coal industry. Then, fans, dust collectors have been used in other industries, although until recently their use is extremely limited. According to Lyautey, ventilators, dust collectors, in some cases quite effective. They give the coefficient of purification from 86% to lead dust and up to 96% on coal. The drawbacks of this method of dust collection - вЂў rapid wear of the fan wheel and a large flow of water.
In conclusion, we mention about the individual recirculation units. These devices are used for cleaning dust-laden air and then return it to the ventilated room.
At present most frequently used type dedusting units of ZIL-900, developed by the automobile plant them. Likhachev. Units are suitable for capturing not dry fibrous dust, for example by grinding, roughing and grinding machines. Productivity of the unit 700 m3 / h, the efficiency of dust removal and 99%. Dust delayed bag filter having a mechanism for shaking. Motor unit power 1.7 kW at n = 2800 rpm. The diameter of the unit 520 mm, height 1820 mm.
Fig. 29. Cell filter Lyke "/ - tying board, 2 - frame with a cloth, and 3 - ears for attachment.
We must bear in mind that these units are very noisy in operation. This fact can not recommend them for installation in production.
Ventilation with air recirculation in the presence of harmful substances are always less efficient than the flow, ie, the fresh air instead of extracted. What we have said is completely true for dust control. Recirculating units can be recommended only for de-dusting machine, working occasionally and briefly during their dispersed location. Recycling units are not to be applied at a constant work pylevydelyayuschih machines or devices, located in concentration. In this case, the design must flow from the ventilation air discharge after cleaning out and compensated drawing supply air.