Polytetrafluoroethylene modified hydrophilic membrane process and treatment applications

With the rapid expansion of urban scale, the serious lack of fresh water resources, low industrial wastewater treatment rate and the deterioration of ecological environment of cities have become the main problems that restrict urban development. The proportion of industrial water consumption in major cities is large. And cooling water usage accounts for 60-65% of industrial water consumption. Thus, solving the problem of recycling and reusing cooling water can bring a boost to the development of cities. In cooling water treatment, it is necessary to remove calcium, magnesium and other scaling ions from the water. These ions are usually precipitated by water treatment agents, and then solid-liquid separation technology is used to achieve this. Traditional solid-liquid separation technologies (such as clarifiers, etc.) have disadvantages such as large footprint, low separation efficiency, narrow application area, low operational flexibility, and inability to remove fine particles. Due to the shortcomings of traditional solid-liquid separation technology, people have been concerned about the development and application of new separation technology, so microfiltration technology realized by using membranes has been developed rapidly. Microfiltration technology utilizes the adsorption, retention and sieving of particles by the very small pores of the microporous membrane itself (generally 0.1-10 microns in diameter). Among many membrane materials, polytetrafluoroethylene (PTFE) is the preferred material for surface filtration at home and abroad because of its non-absorbency, high melting point (327℃), wide temperature range (-200～260℃), non-combustibility and thermal stability, small friction coefficient, especially chemical resistance (resistant to many highly corrosive media), weather resistance and electrical resistance. The extremely low surface tension of PTFE membranes reduces membrane contamination and makes membrane cleaning easier. However, the strong hydrophobicity of PTFE membranes limits their application in aqueous system treatment. This technology is based on the ligand bonding theory to modify the conventional PTFE hydrophobic membrane to obtain hydrophilic PTFE membrane for microfiltration technology in the field of water treatment, and the new technology has a promising application.

Technical index: 1, the filtered solution SS <1mg/L; 2, can be applied under strong acid, strong alkali, strong oxidation, strong solvent conditions; 3, operating pressure 0.05 ~ 0.15Mpa; 4, processing temperature 5 ~ 150 ℃; 5, processing flux 1 ~ 1.1m3/m2-hr; 6, service life ≥ 1 year. Application scope: It can be applied to the factory circulating water treatment, sewage treatment and other fields involving solid-liquid separation and filtration technology. Market Analysis: With the enhancement of people's awareness of environmental protection, the increasingly strict regulations of the environmental protection system, and the serious lack of water resources, the resourceful treatment of industrial and domestic wastewater has become an urgent task, especially for the treatment of industrial wastewater is imminent. This process has the advantages of simple and easy process, low energy consumption, fast separation speed, high separation efficiency and long use cycle, therefore, this project has a wide market application prospect. Benefit analysis: The hydrophilic PTFE membrane modified by this technology has low cost, simple equipment for the whole treatment process, low investment, low operation cost, and greatly reduced energy consumption compared with traditional technology, which has significant economic benefits.