Resourceful treatment system and method for sodium sulfate wastewater

Abstract

The invention discloses a resourceful treatment system and method for sodium sulfate wastewater. The system comprises a collecting tank, a first pH adjusting tank, a Fenton reaction tank, a multifunctional adjusting tank, a horizontal flow sedimentation tank, a multi-stage low-temperature evaporation system, a freezing crystallization device, a sodium sulfate storage device, an incinerator and a tail gas treatment device. The method comprises the steps of (1) carrying out a Fenton reaction; (2) aerating to remove impurities; (3) mixing and precipitating; (4) conducting low-temperature evaporation; (5) conducting freezing crystallization; and (6) performing incineration treatment. The treatment system has the beneficial effects that the treatment system is simple in connection structure and easy to implement; and by means of the treatment system, effective treatment of high-concentration wastewater and low-concentration wastewater is achieved, and meanwhile, effective recovery of sodium sulfate is achieved. According to the treatment method disclosed by the invention, COD in the wastewater is effectively removed through Fenton reaction, aeration impurity removal and mixed precipitation, meanwhile, effective recovery of sodium sulfate resources is realized through low-temperature evaporation and freezing crystallization, the sodium sulfate resources can be sold as products, and the economic benefits of enterprises are improved.

Description

Technical field: [0001] The present invention belongs to the technical field of industrial wastewater treatment, and more particularly to a resource treatment system for sodium sulfate wastewater and a treatment method thereof. Background technique: [0002] The chemical industry produces a large amount of sodium sulfate wastewater, which includes high concentration wastewater (containing salt content ≥1 million mg / L, COD ≥ 20,000 mg / L) and low concentration wastewater (including salt content of <100,000) Mg / L, COD <20,000 mg / L), if these wastewater is discharged directly into the natural environment without purification, it will lead to water and soil contamination, destroy soil structure, leading to soil strips, which is not conducive to the growth of animals and plants. Pollution is caused to the environment. [0003] At present, the treatment process of sodium sulfate wastewater is mainly: pretreatment - regulating pool - air floating pool - two aeration - fento...

AI Technical Summary

Problems solved by technology

[0002] The chemical industry produces a large amount of sodium sulfate wastewater. Due to different sources of wastewater, it includes high-concentration wastewater (salt content ≥ 100,000 mg / L, COD ≥ 20,000 mg / L) and low-concentration wastewater (salt content < 100,000 mg / L) mg / L, COD<20,000 mg / L), if these wastewaters are directly discharged into the natural environment without purification treatment, the water body and soil will be polluted, the soil structure will be destroyed, and the soil will be compacted, which is not conducive to the growth of animals and plants. pollute the environment

[0003] At present, the treatment process of sodium sulfate wastewater is mainly: pretreatment-regulating tank-flotation tank-two-stage aeration-Fenton oxidation-flocculation sedimentation-ozone oxidation-activated carbon filtration, but the following problems exist in the above-mentioned process: 1. The quality of the treated sewage is relatively complex, among which strong acid and high oily sewage account for the majority, so it is easy to corrode metal equipment and structures during the pretreatment process; 2. On the one hand, due to the high concentration of COD in the wastewater, it contains a large amount of Organic matter with high biological toxicity and difficult to degrade is difficult to be directly biodegraded. On the other hand, high-salt wastewater will affect the survival of bacteria in the biochemical system and cannot be completely treated directly by biological methods; 3. The recovery of sodium sulfate cannot be realized by the above-mentioned process , resulting in a waste of resources

Images