Tóm tắt nội dung:   Hood and  Ductwork Design 20.1 INTRODUCTION The design of hoods and ductwork is often a very important part of air-pollution control. Hoods and the air exhausted must be adequate to prevent escape of con-taminants to the atmosphere. On the other hand, the air exhausted through a hood must usually be treated to remove the contaminant. Therefore, to keep capital and operating costs of control equipment to a minimum, no more air should be exhausted than necessary for complete capture. By...