Integrated sewage treatment technology and system for tin-removing wastewater

Abstract

The invention provides a tin-removing wastewater treatment technology. The tin-removing wastewater treatment technology sequentially comprises the following steps: recycling metal components by adopting neutralizing-precipitating; removing organic pollutants by utilizing UV / Fenton advanced oxidation processes; and then, performing biochemical denitrification process in a denitrification filter. The tin-removing wastewater treatment technology is capable of effectively removing metal ions, including tin ions, copper ions and the like, as well as organic compounds from tin-removing wastewater; moreover, biochemical denitrification process is also performed on the wastewater, so that discharged wastewater meets relevant environmental protection standards. The invention further provides a tin-removing wastewater treatment system which is capable of synchronously recycling metals from tin-removing wastewater and ensuring that the treated wastewater meets environmental emission standards. The system is integrated wastewater treatment equipment which is capable of performing on-site treatment and small in floor area; and the system is composed of two parts, including an integrated tin metal and UV cooperative oxidation treatment station which can be designed as a vehicle-mounted system, and an on-site biochemical sewage treatment station. The integrated tin-removing wastewater treatment system is economical, highly efficient and suitable for wide application in industrial production.

Description

technical field [0001] The invention relates to the field of wastewater treatment, in particular to a process for recycling and treating tin-stripping waste liquid, an integrated mobile treatment system for recycling and treating tin-stripping wastewater, and a method for treating tin-stripping wastewater by using the tin-stripping wastewater recovery and treatment system. Background technique [0002] With the rapid development of my country's electronics industry, a large number of PCB processing factories have emerged, and China is one of the countries with the highest proportion of PCBs in the world. Global annual consumption 5×l0 5 m 3 Tin stripping solution, the annual consumption of tin stripping solution in my country is 6×10 4 m 3 , and increase at a rate of 15%-18%. If such a large amount of tin stripping water is discharged without treatment, it will inevitably cause great pollution to water resources and the ecological environment. However, due to the comple...

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Problems solved by technology

If such a large amount of tin stripping water is discharged without treatment, it will inevitably cause great pollution to water resources and the ecological environment

However, due to the complex composition and strong corrosiveness of tin stripping wastewater, it is difficult to deal with and the cost is high. Especially for some developing PCB small and medium-sized enterprises that lack technology and funds, the treatment of tin stripping wastewater has become the bottleneck of enterprise development.

[0003] At present, when the tin stripping water waste liquid is treated according to the method of "territorial management, decentralized transportation, and centralized treatment", the treatment process mainly adopts a simple neutralization and precipitation method to recover the intermediate product of tin sludge, which may cause:

[0004] 1. Loss during transportation, or leakage of hazardous waste;

[0005] 2. The economic value of the extracted by-product tin sludge is relatively low;

[0006] 3. It takes a lot of cost to deal with other components such as ammonia nitrogen in the wastewater after tin stripping

In the traditional A / O denitrification process, because the anoxic section and the aerobic section share a set of sludge return system, it is difficult to domesticate the dominant bacteria with specificity and uniqueness, and the degradation effect on refractory substances needs to be improved; The improvement of denitrification efficiency must rely on a high internal circulation ratio, thus increasing operating costs

In addition, the reflux of the mixed solution comes from the aerobic tank, which has a corresponding concentration of dissolved oxygen, which increases the DO in the anoxic section, affects the decontamination effect, and makes it difficult to improve the nitrogen removal efficiency, which is generally kept below 90%.

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