Experimental study on improving the purification efficiency of formaldehyde waste gas with bio-trickling filter

The effect of sodium sulfite on improving the purification efficiency of formaldehyde waste gas in a bio-trickling filter was investigated. In the study, 0.05 M sodium sulfite was added in the trickling liquid. The results showed that sodium sulfite efficiently removed the formaldehyde that was solved in the trickling liquid. The removal efficiencies were high up to 98.9%. The apparent slow bio-reaction rate of purifying formaldehyde was increased by 2.63mg/m².h, and the enhancement factor of the slow bio-reaction was increased to 0.61. Sodium sulfite improved the purification efficiency of formaldehyde waste gas. The results are useful for developing practical and efficient techniques for purifying formaldehyde waste gas.