Development And Applied Research Of Environmental Chamber For Air Cleaner Detection

On the measurements of newly renovated housings and offices,it proved that decoration produces tremendous impact on indoor air quality, and the main pollutants are formaldehyde and total volatile organic compounds (TVOC). Select 18 rooms within the three floors in the same office building,which are in the similar decorated, and test pollutant removal efficiency of every room with several types of air cleaner. The result show that the cleaning performance have been rather uneven, some air cleaner's cleaning efficiency is even lower than the natural decay rate. The test environment and evaluation method is imperfect and it will be resulted in poor quality air cleaner used in daily life. In order to assess different type of air cleaners sciencely and fairly, the environmental chamber is developed.The environmental chamber is made of the inner chamber, outer chamber, air purification system, pollution source device and air sampling system. Among them, the inner chamber with the volume of 30m3 is the key part of the test chamber. The experimental result shows that the deviation of temperature and relative humidity (RH) areδT≤2.5℃andδRH≤5% respectively. The body leakage is 0.05-2.0 m3/h under pressure difference of 0-5 Pa between the inside and the outside of the chamber. After cleaning,with the single pollutant background concentration less than 30μg/m3, TVOC is less than 100μg/m3. The recovery rate of the chamber system are 86.6%,83.4%,82.9% and 81.5% under four kinds of amount of 37% formaldehyde solution for the representation of pollutants. Under the conditon of 21℃and RH 40%, the natural decay of four kinds of pollutants which are formaldehyde,benzene,toluene and ammonia in this chamber are 6.7 %,8.9%,7.5%and 4.7%.The original pollution source device in the environment chamber is modified and compared the performance by testing in three phases,Large amounts of data and charts show that performance of new equipment has been improved greatly,it can release various of pollutants to the environment chamber more rapidly and enenly. the concentration is stable and controllable. On the basis of a wide range of contaminants were test, summed up the essential characteristics of all pollutants, and made into concentration-time curve, can be realized indirectly quantitative.Using the the large environmental chamber, select formaldehyde as the representative pollutants, and evaluate the cleaning performance of 6 sets air cleaners by the methods of deducting natural decay rate. The data showed that cleaners of different technologies produce significant differences in cleanning efficiency, the removal efficiency of cleaner with same kind of technology is also different. Even the same air cleaner which is maked adjustments in key technology,The cleaning efficiency is also very different. Experimental result shows that the environmental chamber runs well,and detailed measurement of the difference in cleaning efficiency.Therefore,It can obtain accurate assessment relatively which can reflect the true removal efficiency of specific air cleaning products.