Difference Between Ductless Fume Hood and Traditional Fume Hood
The traditional fume hood is exhausted, and the toxic gas that is pumped out will be discharged directly to the outside through external pipes from the bottom up. This may not only cause harm to the environment, but the fan will continue to draw indoor air and consume a large amount of air. Air-conditioning energy consumption, resulting in energy waste. In addition, when a duct fume hood is installed, it needs to undergo professional laboratory planning and design, heavy layout and construction, a lengthy process and high cost, and once the construction is completed, modification is very inconvenient. Have to be equipped with good ventilation and make-up systems. However, traditional fume hoods are generally cheaper.
The ductless fume hood is equipped with a fan and a filter at the top. The fan draws air from the bottom to the top. The filter absorbs and removes the toxic and harmful substances in the airflow, and then the safe airflow is discharged to the laboratory, which circulates. The ductless fume hood does not require external pipes, no pollution gas is discharged into the atmosphere, and there is no need to exhaust indoor air. It is energy-saving, environmentally friendly, easy to move, and can be flexibly changed according to the layout of the laboratory. The ductless fume hood is fully assembled at the time of delivery and there is no complicated installation process, which saves a lot of time and manpower.
In terms of scope of application, traditional fume hoods do not limit which chemicals are used, nor do they limit the amount of chemicals used. These volatile chemicals are directly discharged outdoors. The ductless fume hood uses activated carbon filters to purify the gas. For different types of chemicals, different types of activated carbon filters need to be selected. Different activated carbon filters have different filtration efficiency for a specific chemical. When selecting a filter type, you need to consider the type of chemicals that the fume hood will use. In addition, the adsorption of the filter will reach saturation. Monitoring the saturation of the filter is very necessary for the ductless fume hood. When the filter reaches saturation, it should be replaced regularly.