[Study on the effect of activated carbon on formaldehyde in clean workshop].

Objective: To study the effect of activated carbon on the purification of formaldehyde in the clean workshop return air purification device and its influencing factors. Methods: From May to June 2018, choosed 4 different commercial activated carbons (bamboo charcoal, 1-3 mm, 3-5 mm; coconut shell charcoal, 6-12 mesh, 8-16 mesh) to make 5 types of activated carbon purification net. In the simulated clean plant laboratory, the detection of occupational disease hazards was used to test the purification effect of different types of activated carbon purification nets on formaldehyde. Results: The purification effect of different types of activated carbon increased with the prolongation of purification time, and the difference was statistically significant (P<0.05) . Compared with other types of activated carbon, coconut shell charcoal (8-16 mesh, double layer) had the best purification effect, 15 min and 30 min purification efficiency was 58.72% and 85.20% respectively, and the difference was statistically significant (P<0.05) . The purification effect of double-layer coconut shell charcoal was better than single layer (P<0.05) . The purification effect of double-layer coconut shell charcoal (8-16 mesh) was better than double-layer coconut shell charcoal (6-12 mesh) , the difference was statistically significant (P<0.05) . Coconut shell charcoal (8-16 mesh, double layer) had better purification effect than bamboo charcoal (P<0.05) . Conclusion: Different specific surface area, particle size, and thickness of activated carbon have a certain effect on the purification effect of formaldehyde, and its selection has a certain significance in improving the occupational health protection level in the clean plant, solving the safe use of return air and reducing energy consumption.