1. technical name

Ultrafiltration membrane Fenton technology for advanced treatment of industrial wastewater.

2. scope of application

Advanced treatment of industrial wastewater from papermaking, textile, chemical and other industries, fermentation wastewater, landfill leachate, and industrial park wastewater.

3. technical content

3.1 Technical principle Ultrafiltration membrane Fenton is a new and efficient industrial wastewater advanced treatment technology produced by improving traditional Fenton technology and organically combining it with membrane filtration. It has a significant effect on treating non-biodegradable dissolved pollutants. Membrane Fenton eliminates the traditional Fenton sedimentation tank, adds ultrafiltration membrane as a solid-liquid separation unit, and adds innovative parallel internal reflux design to form its unique operating parameters and achieve hydraulic retention time and sludge retention time. Separation; The range of operating parameters is wider, and the solid-liquid separation process is not limited by settling speed and settling time. Through membrane concentration, the system maintains high sludge concentration operation, and integrates various water treatment technologies such as coagulation adsorption, chemical oxidation, and membrane filtration to achieve Efficient removal of pollutants COD, TP, TSS, and F-. The membrane filtration accuracy of this technology is 0.04μm, the sludge concentration in the membrane pool is 4000mg/L to 8000mg/L, and the membrane flux is usually 15L/(m2·h) to 30L /(m2·h).

3.2 main innovations

(1) The traditional Fenton or fluidized bed Fenton sedimentation tank has been eliminated, which greatly reduces the floor area while optimizing the treatment effect; through the parallel internal reflux design, it integrates in-phase Fenton and heterophase Fenton, coagulation and adsorption, chemical complex precipitation, ultrafiltration membrane filtration and other water treatment technologies; By combining the ultrafiltration membrane process and utilizing its interception effect of small pore size, macromolecular colloids and suspended solids are further removed to ensure that COD and TSS meet high standards for discharge or reuse. (2) Effective control of membrane pollution. On the one hand, the strong oxidizing property of Fenton reagent itself can effectively inhibit membrane pollution; on the other hand, different maintenance (MC) cleaning modes and cleaning agents are optimized to explore the best combination that can effectively control membrane pollution and achieve long-term stable operation. (3) The concentration effect of the newly added ultrafiltration unit and the iron mud reflux design can maintain the high sludge concentration operation of the entire system, increase the concentration of reaction substrates, effectively prevent the loss of iron catalysts, and improve advanced oxidation efficiency.

4. Pollution control or environmental restoration effects

Compared with traditional Fenton and fluidized bed Fenton processes, this process can save more than 60%, increase COD removal rate by 20%~30%, and reduce the dosage of Fenton reagent by 30%~ 60%. The sludge discharge volume can be reduced by 30%~ 60%, without adding PAM.

5. Technology demonstration

The 2000m3/d advanced treatment demonstration project of wastewater in Nansha District Fine Chemical Industry Park in Guangzhou City has the main process of pretreatment + homogenization tank + A2O +MBR+ membrane Fenton. After primary treatment and secondary biological treatment, when the COD is 50mg/L to 200mg/L, the COD treated by membrane Fenton technology can meet the Class III water standard of GB3838-2002 or the Class I A standard of GB18918-2002; When TP≤2mg/L, the TP of the effluent can meet the Class III water standard of GB3838-2002. The removal rate of low concentration fluoride ions (2mg/L~10mg/L) reached 70%, and SS was not detected. The process runs stably and can be operated automatically to achieve unattended operation.

6. investment estimation

According to the differences in treatment scale and system configuration perfection, the investment in water construction is 900 - 1,700 yuan.

7. investment recovery period

The static investment payback period is 1.6 years.

8. Prospects for transformation and promotion of technological achievements

Since the launch of the ultrafiltration membrane Fenton demonstration project in 2018, the construction of membrane Fenton application projects has been launched in many regions and multiple water plants. The process has significant effects on treating refractory pollutants, fully meets the increasingly stringent environmental requirements at home and abroad, saves energy and reduces consumption, and can achieve comprehensive utilization of resources. With the increasing requirements for advanced treatment of industrial wastewater, the upgrading of existing sewage treatment plants, and the improvement of water reuse rate requirements, huge market potential has been released, and ultrafiltration membrane Fenton technology has good industrial application prospects.