Ozone oxidization-precipitation-sand filtering-iron powder filtering treatment process for alkali-minimization wastewater in printing and dyeing industry

Abstract

The invention discloses an ozone oxidization-precipitation-sand filtering-iron powder filtering treatment process for alkali-minimization wastewater in the printing and dyeing industry. The treatment process comprises the following steps: (1) pretreating the alkali-minimization wastewater, and recovering terephthalic acid and a salt thereof; (2)introducing ozone into the pretreated wastewater to perform oxidization treatment; (3) adding a soluble ferric salt into sewage treated by ozone oxidization to perform precipitation treatment; (4) introducing the precipitated wastewater into sand filtering equipment to perform filtering treatment; (5) introducing the sand-filtered wastewater into iron powder filtering equipment to obtain purified water. By adopting the treatment process, ketones, alcohols, organic amine, benzene series, thiophene and a part of organic esters in water can be removed effectively. After continuous running for half a year, the COD (Chemical Oxygen Demand) removal rate is kept at 96 to 99 percent, the chromaticity removal rate is 97 to 99.9 percent, and the amine-nitrogen removal rate is kept at 93 to 98 percent.

Description

technical field [0001] The invention relates to the technical field of wastewater treatment, in particular to an ozone oxidation-precipitation-sand filtration-iron powder filtration treatment process for alkali reduction wastewater in the printing and dyeing industry. Background technique [0002] Printing and dyeing is a traditional characteristic industry in my country. In recent years, it has developed rapidly in Jiangsu, Zhejiang, Guangdong and coastal areas. However, the pollution caused by printing and dyeing wastewater has become increasingly prominent with the expansion of the industrial scale. The printing and dyeing industry is a large discharge of industrial wastewater. According to incomplete statistics, the daily discharge of printing and dyeing wastewater in my country is about [0003] In recent years, the share of polyester chemical fiber in the textile market has been increasing. In 1991, my country's polyester output was 1.015 million tons. By November ...

AI Technical Summary

Problems solved by technology

Due to the corrosion of the outer fiber by alkali, the polyester fiber becomes thinner and softer after reduction, resulting in a silk-like soft feel and elegant feeling, but the reduction of polyester also brings high concentration, high alkalinity, and difficult to degrade Organic Wastewater - Alkali Mineral Wastewater