大学工业通风考题(国外英文资料).doc

大学工业通风考题(国外英文资料) The design of a local exhaust hood should follow the following principles: the principle of the local exhaust hood should be as close as possible sources of pollutants, the pollutants is limited in a small space, as far as possible to reduce the suction range, easy to capture and control set. The air flow direction of exhaust hood should be consistent with the direction of movement of air pollution. The inhaled air has been contaminated by the breathing zone is not allowed. Design should take full account of the operators location and range of activities. The hood should be has the advantages of simple structure, low cost, convenient manufacture and installation and disassembly and maintenance. It should be as far as possible to avoid or weaken the interference of air, such as drafts, effects of air flow on the air flow. The wind: in the local place or the whole plant to air pollution do not conform to the hygiene standards after treatment reaches the emission standard to discharge. Air intake: a fresh air or purified air that is in accordance with hygienic standards is sent into the room at the local site or in the whole workshop. Partial ventilation: local ventilation is the use of local airflow ventilation, so that the local work place is not contaminated by pollutants, and create a good working environment. 3 local exhaust system by local exhaust hood, air duct (pipeline gas ventilation system) (to reduce short and straight, turning, beautiful and simple), purification equipment (divided into dust and pollution gas purification device) and a fan (fan exhaust system to provide air flow of power machinery). Local air supply: there is no need to supply air to the whole workshop. The air supply can only be sent to the individual working place, and it will cause a good air environment in the local work place. The overall ventilation hand with clean air dilution concentration of pollutants in indoor air, and at the same time the polluted air to the ou