In fact, there are many unhealthy substances in our indoor air, that is, our indoor air is not very fresh, so we need to improve our air quality, so we need to replace our indoor air, especially harmful gases, and it is very important to remove them. At the same time, however, energy is often consumed in a large amount, so the requirements of the ventilation control system in the laboratory are getting higher and higher, from the early CV (constant air volume), 2-State (bistable), VAV (variable air volume) systems to the latest adaptive control systems - both safe and in line with the needs of energy conservation. In a word, the latest concept of the laboratory is to treat the entire laboratory as a fume hood. How to effectively control various intake and exhaust gases to achieve safe and economic results is crucial. The commonly used exhaust equipment in the laboratory mainly includes: fume hood, atomic absorption hood, universal exhaust hood, ceiling exhaust hood, platform exhaust hood, etc. The fume hood is the most common.
The fume hood is a ventilating device for safe handling of harmful and toxic gases or vapors. It is used to capture, seal and transfer pollutants and harmful chemical gases, and prevent them from escaping into the laboratory. In this way, the pollutants in the working area can be inhaled to keep them away from the operator, so as to minimize inhalation contact. The airflow in the fume hood is to draw the air in the laboratory into the fume hood through the exhaust fan, dilute the polluted gas in the fume hood and exhaust it outdoors through the exhaust system, which can achieve low concentration diffusion;
Universal exhaust hood is the first choice for local ventilation: simple installation, flexible positioning, good ventilation performance, which can effectively protect the personal safety of laboratory staff;
The atomic absorption hood is mainly applicable to all kinds of large precision instruments. It requires positioning installation and has set ventilation performance parameters. It is also one of the factors that must be considered in the overall laboratory planning;
The exhaust hood is mainly applicable to chemical laboratories. It is one of the necessary equipment to solve the overall ventilation requirements of such laboratories.
At present, our company mainly adopts axial flow fans (diagonal flow fans, pipe fans) and centrifugal fans. Axial flow fan is applicable to ventilation system with small wind pressure and short pipeline (generally within 10m, otherwise it may cause pumping failure); The centrifugal fan is applicable to the ventilation system with long pipeline (generally more than 10m, otherwise it may cause loud noise). Fan material: generally divided into glass fiber reinforced plastic, PP, PVC, iron sheet, etc., with more glass fiber reinforced plastic. The fan model is selected according to the air volume and air pressure.