Method for treating polyvinyl chloride wastewater

Abstract

The invention relates to a method for treating polyvinyl chloride (PVC) wastewater and belongs to the field of environment-friendly wastewater treatment. The method comprises the following three processes: filtering, hydrolytic acidification and BAF (aerating biological treatment tower). A combined process is adopted for treating the PVC wastewater, the COD removal rate is above 70%, the ammonium-nitrogen removal rate reaches up to 90%, the operation is simple and the cost is low.

Description

technical field [0001] A method for treating polyvinyl chloride wastewater belongs to the field of wastewater treatment and environmental protection. Background technique [0002] Polyvinyl chloride (PVC) is one of the three major general-purpose plastics in the world. It is easy to process products such as molding materials, pipes, plates, sheets, etc. It has good flame retardancy, chemical corrosion resistance, electrical insulation, and is light in weight and strong. Higher and lower cost, it is widely used in packaging, construction, industrial and civil pipelines, cable sheathing and many other fields. Its production capacity is also increasing year by year. In 2005, the world's PVC production capacity was 34.07 million tons / year, and the output was 32.437 million tons; in 2006, the world's PVC production capacity increased by 4.5%, reaching 35.62 million tons / year, and the output slightly increased to 32.62 million tons. By the end of 2006, the total production capaci...

AI Technical Summary

Problems solved by technology

Domestic chlor-alkali enterprises generally mix PVC wastewater with other production wastewater for treatment, and discharge it after reaching the second-level discharge standard of the "Discharge Standard for Caustic Soda and Polyvinyl Chloride Industrial Water Pollutants (GB15581-95), or discharge it according to the requirements of the enterprise and the local government , after the comprehensive treatment reaches a certain discharge standard, it will be discharged into the sea; due to the shortage of water resources in its own environment, some enterprises use simple treatment for flushing water and even try to use it as process water, but most of them stay in the experimental stage and truly realize industrialization. rare

[0004] In the domestic experimental research on the treatment of PVC wastewater, the method of flocculation-oxidation was mostly used at first. Although it can reduce its COD concentration, it cannot be reused due to problems such as corrosion; Good results have been achieved, but due to the limited ability to remove COD and high operating costs, it has not been promoted. In addition, due to different production technologies in various enterprises, the water quality of wastewater produced is also different. Therefore, PVC wastewater The disposal and reuse of chlor-alkali enterprises in China has always been a difficult problem to solve