The purpose of the fume hood and classification

日期:2024-07-21 11:17
The purpose of the fume hood and classification

Laboratory ventilation is an indispensable part of in the design of laboratory. In order to make the laboratory staff do not inhale or pharynx into some unknown toxic and can cause or toxicity of chemicals and organisms, the laboratory should have good ventilation. To prevent some of the steam, gas and particles (smoke, soot, dust and air suspension) absorption of pollutants must be used fume hoods and ventilation hood or local ventilation method to remove.

Fume hood is the most commonly used in the laboratory of a local exhaust equipment, variety, due to the different structure, use condition is different, the ventilation effect is not the same. The performance of the fume hood good ring, mainly depends on the speed of the move through the air of the fume hood.

According to the ventilation way classification: is divided into upper exhaust type, lower exhaust type and three types of upper and lower exhaust type at the same time. Uniform wind speed, in order to ensure the work area for the cooling process of fume hood should use the lower exhaust type, for thermal process of the fume hood adopt upper exhaust type, the calorific value of the unsteady process, air outlet can be set in both up and down along with the change of calorific value contained in the adjust the ratio of upper and lower exhaust air volume, and uniform wind speed is obtained.

Classification according to the way into the wind: and all exhaust ventilation cabinet: through indoor in the back wind circulation inside ark out outdoor called total exhaust type, this is a type of application is very broad. Fill the wind ventilation cabinet: when the fume hood set in heating or is required to control the temperature and humidity room, to save on heating, air conditioning energy consumption, using wind circulation inside ark from the outdoor supplies out of the back is called wind type fume hood. Variable air volume fume hood: ordinary constant air volume system requires manual adjustment of the fixed blade of wind valve, adjust the fume hood exhaust air, when the regulating valve to a certain Angle to surface wind speed of hope. Variable air volume control is by regulating valve sensor to change the face of the air flow to achieve a given wind speed, of course, the standard type of low cost and high cost of variable air volume, suitable for high accuracy required.

According to use classification: can be divided into the integral lower open, floor, two, three surface glass, the table type, even the asana and designed according to the needs of different experimental use of radioactive experiment, synthetic experiment, right of chlorate experiment dedicated fume hood.
The purpose of the fume hood and classification