With the continuous improvement of industrial production technology, water treatment is getting closer and closer to our daily lives. Ultrafiltration technology has been widely used in drinking water treatment, wastewater industrial sewage treatment, RO reverse osmosis pretreatment and other fields.
1. Working principle of ultrafiltration membrane
Uf membrane module is the entire screening process related to the membrane diameter. The pressure difference between both sides of the membrane is the driving force, and uf membrane module is used as the filtering material. Under a certain working pressure, when the original liquid passes through the membrane surface, the ultrafiltration Many microplates on the membrane surface only allow water and small molecular water chemicals to pass through the liquid. The organic matter whose volume exceeds the micro-diameter of the membrane surface is cut off by the leaking side of the membrane and becomes the extract, which completes the purification, separation and dissolution of the original solution.
2. Filtration method of uf membrane module
a. Internal pressure filtration
The original liquid first enters the inner thread of the membrane filament, is pushed by the pressure difference, and penetrates into the hollow chemical fiber from the inside to the outside along the axial direction. The internal pressure filtration is carried out through the liquid. The rapid passage in the radial direction can wash away the contaminants attached to the surface of the inner pores of the membrane and repair the water diffusion coefficient of the membrane.
b. External pressure filtration
The original liquid penetrates into the membrane filament from the outside in the axial direction through the pressure difference to become the passing liquid. When the intercepted chemical substance accumulates outside the hollow filament, it is external pressure filtration. The external pressure ro uf membrane is sealed in the membrane shell, and there are many blind areas of flowing water, and the contaminants attached to the membrane surface cannot be removed by a rapid impact method, and the contaminants cannot be completely removed.
c. Dead end filtering
When the concentration of the chemical substances separated in the raw liquid is very low, in order to better reduce energy consumption, all the water in the raw liquid penetrates into the filter membrane, and no extraction liquid is discharged. Generally, dead-end filtration, or full filtration, is selected.
d. Cross-flow filtration
During filtration, some concentrated liquid is discharged from the other end of ro uf membrane. When the concentration of chemical substances in the original liquid that can be cut by the membrane is high, the frictional resistance of the membrane will increase rapidly. At this time, cross-flow filtration is commonly used.
3.The characteristics of uf membrane module
(1). It is separated at normal temperature and low voltage, so energy consumption is low, thereby reducing operating costs.
The mechanical equipment is small in size, simple in structure, and low in project investment costs.
The entire separation process of uf membrane module is simple pressurizing and conveying liquid, and the production process is simple, which is convenient for actual operation, maintenance and management.
The water diffusion coefficient is large, the filtration precision is high, and the water utilization rate is high.
Low product cost and low operating cost.