Vải lọc thu, baghouses, tách hạt khỏi dòng khí bằng cách gây ra các hạt đi qua một phương tiện truyền thông lọc, một lớp hạt đã thu thập trước (hoặc cố ý gửi), hoặc cả hai. Các hạt gasborne bị chặn bởi các sợi của các phương tiện truyền thông lọc, bởi các hạt đã được hiện diện trên bề mặt phương tiện truyền thông, hoặc cả hai. Để ngăn chặn giảm áp lực quá mức như các hạt tích tụ, các thiết bị này sử dụng các cơ chế khác nhau để tháo gỡ các hạt từ các. | chapter 7 Fabric filter collectors Device type Fabric filter collectors or baghouses separate particulate from gas stream by causing the particulate to pass through a filtering media a layer of previously collected or purposely deposited particulate or both. The gas-borne particulate is intercepted by the fibers of the filtering media by the particulate already present on the media surface or both. To prevent excessive pressure drop as the particulate accumulates these devices use various mechanisms to disengage the particulate from the media. Typical applications and uses There are three basic dust collector applications. Nuisance venting of conveyors transfer points packing stations and so on this dust is often sent to waste. Next is product collection venting of classifiers crushers storage bins air pneumatic conveying systems mills and flash dryers. This dust is often recovered because it has value. Last is process gas filtration venting of spray dryers kilns power boilers reactors and so on. The collected solids may or may not be returned to the process. This dust may or not be worth recovering but must be controlled for environmental or workplace health reasons. Fabric filter collectors are also currently used for gas absorption applications wherein the fabric filter collector is preceded by a spray dryer dry Venturi ductwork injection system or the bags are precoated with an adsorbent or absorbent. Sodium bicarbonate precoat for example has been used to remove gaseous SO2 from power boiler exhaust gases. A precoat of lime or a spray dried slurry of lime has also been used on many applications to simultaneously remove particulate and acidic gases. When toxic dioxins are present some applications use activated carbon as part of the precoat. Figure shows a baghouse preceded by an evaporative cooler on a cupola operation. The hot gases enter from the bypass stack at the left and This chapter is contributed by Deny Claffey and Michael Claffey Allied .
