Abstact
Biological pollution has a bad influence on the running process of industrial ro water systems. It greatly reduces the role of membrane technology in water treatment. Study the formation of biological pollution in industrial reverse osmosis water system. Analyze the characteristics of non-oxidizing biocides. Take DBNPA as an example.
The development of commercial ro water system benefits from the polyamide composite reverse osmosis membrane. It reduces the industrial reverse osmosis system cost. Industrial ro water systemscan be widely used in water purification technology.
At the same time, reverse osmosis membrane began to be used in various fields. Especially in water treatment that contains microorganisms. However, how to control biological pollutants in water of reverse osmosis is an urgent problem.
1.How does biological pollution form in industrial ro water systems?
The formation process of biological pollution in reverse osmosis system can be divided into four stages.
① The formation of adsorption conditions on the membrane surface.
② The initial adhesion of organism to membrane.
③ The irreversible adhesion of organism to membrane surface.
④ The growth and reproduction of organisms.
If it develops to the fourth stage, the biological pollution in the reverse osmosis system can not be effectively controlled.
2. How to control biological pollution?
The common methods include physical method, chemical cleaning method and adding bactericide method. Different methods are compared as follows.
Physical method is through ultraviolet, ultrasonic, magnetic treatment. The advantage is that it is environmentally friendly. The disadvantage is that there is no continuous bactericidal effect and the effect is not ideal.
Chemical cleaning is a method after the occurrence of biological pollution. Moreover, it can not effectively control the recurrence of biological pollution.
The biocide method is the most cost-effective method to control bio pollution in reverse osmosis system.
There are two kinds of biocides: oxidizing biocides and non oxidizing biocides.
Oxidizing bactericides include Cl2, NaClO, O3, H2O2, etc. Among them, Cl2 and NaClO are widely used. However, polyamide reverse osmosis membrane has no oxidation resistance. After reverse osmosis water treatment, it is necessary to dechlorinate the water. This increases processing costs. And this method can not effectively avoid the recurrence of biological pollution. Therefore, the use of non oxidizing biocides for biological pollution control, the effect is better.
3. Performance of DBNPA, a non-oxidizing biocide.
The bactericidal rate of DBNPA was not affected by pH value in water. The intermediate and final products of DBNPA degradation meet the relevant environmental standards. They have no biological pollutants in water.Therefore, DBNPA has no pollution to ro water quality.
DBNPA can be used in RO system to kill and remove biological pollution before the fourth stage. The continuous operation of reverse osmosis system is guaranteed.
4. Conclusion.
The best time to control bio pollution is before the growth and reproduction of organisms. The use of non oxidizing fungicides can better inhibit the formation of biological pollution in reverse osmosis system. The above is about how to effectively control biological pollution in reverse osmosis system.