Formaldehyde wastewater pretreatment method

Abstract

A formaldehyde wastewater pretreatment method is disclosed and comprises the following steps: (1) inputting formaldehyde-containing wastewater into a formaldehyde wastewater collection tank, and adding liquid caustic soda into the formaldehyde wastewater collection tank to adjust the pH value of the formaldehyde wastewater to 11-13, and (2) preheating the formaldehyde wastewater of which the pH value is adjusted through a heating device, preheating the formaldehyde wastewater to 60-80 DEG C, inputting the preheated formaldehyde wastewater into a formaldehyde wastewater catalytic reaction tower, presetting calcium carbonate in the formaldehyde wastewater catalytic reaction tower, and performing glycan reaction on formaldehyde and liquid caustic soda under the catalytic action of the calciumcarbonate to obtain a glycan product, and a metering pump is arranged on a pipeline for connecting the heating device with the formaldehyde wastewater catalytic reaction tower, the metering pump controls the preheated formaldehyde wastewater to enter the formaldehyde wastewater catalytic reaction tower, and the retention time of the formaldehyde wastewater in the formaldehyde wastewater catalyticreaction tower for glycan reaction is 3-5 hours.

Description

technical field

[0001] The invention belongs to the technical field related to sewage treatment, and in particular relates to a pretreatment method for formaldehyde wastewater. Background technique

[0002] As an important industrial raw material, formaldehyde is widely used in paint, coating, medicine, chemical industry and other fields. Due to the high toxicity of formaldehyde, it is listed as a class I carcinogen. It will directly react with the protein, DNA, and RNA in the microorganism, causing the death of the microorganism or inhibiting its biological activity. When the formaldehyde content exceeds 200mg / L, the biochemical treatment of wastewater Microbial activity is almost completely inhibited during the process, so the treatment of formaldehyde wastewater is strictly regulated, and the development of its wastewater treatment technology is also highly valued by the industry. Therefore, high-concentration formaldehyde wastewater must undergo appropriate pretreatment...