Study on the Treatment of Formaldehyde Wastewater by Addition Reaction

The best experimental factors were achieved through the single factor experiment and orthogonal experiment. When the initial concentration of formaldehyde was 120 mg/L, reaction time was 30 minutes and the ratio between amount of sodium bisulfite and formaldehyde was 3:1, the removal rate of formaldehyde was approximately up to 100%, which fully satisfied the national emission standards (the concentration of formaldehyde≤ 1 mg/L). The actual wastewater project was verified according to these factors. The tannery wastewater containing formaldehyde which the initial concentration of formaldehyde was 120 mg /L was reacted with sodium bisulfite. The concentration of remaining formaldehyde was reduced to 0.446 mg/L 30 minutes later, which fully satisfied the national emission standard. The process was practicable.