The Research On Regeneration And Operation Properties Of Abandoned Rolled Polyamide Reverse Osmosis Membrane Element

As everyone knows, our life cannot do without fresh water, however, the earth's serious shortage of freshwater resource.How to develop and conservation of freshwater resources to provide enough clean water for human survival and development is one of the world's most difficult and most pressing problem. At present, the application of reverse osmosis water treatment technology extensively, throughout the world, and the rapid development, the technology is mature. The continuous development of reverse osmosis technology broadens the reverse osmosis market.And with the expansion of the market, there are tens of thousands of reverse osmosis membrane was eliminated, abandoned every year. Thus causing not only much environmental pollution, but also a waste of resources. Therefore, all countries are actively looking for the way of reusing waste reverse osmosis membrane element. Devoted to the study of wasted reverse osmosis membrane recycling to reduce waste quantity of reverse osmosis membrane, to reduce environmental pollution and reduce the cost of water treatment, reuse the resources.After many experts and researchers painstaking research, now has developed a number of regeneration method of waste reverse osmosis membrane. Fibiger using water soluble polymer method in polyamide reverse osmosis membrane surface coating containing carboxyl groups to improve desalination waste reverse osmosis membrane rate. Jose M. Veza using potassium permanganate solution in certain concentration to oxidation the surface of membrane element, total separation efficiency of regeneration membrane to reach 97%. Li Baoguang used the method of chemical cleaning and sodium hypochlorite oxidation combined to waste and polyamide reverse osmosis membrane regeneration, regeneration desalination membrane reflects the good performance. Zhejiang University professor Yu Sanchuan Et al modified the membrane element with amine containing solution. after treatment, the membrane performance some separation. Xin Yongguang first using a specific oxidant to oxidation the abandoned membrane element and then circulating immersion by amine containing solution. Properties of recycled film obtained with filter membrane, longer service life, and design a set of RO membrane cleaning waste regeneration unit, is expected to enter the market. The subject on the basis of previous studies, drawing on some of their methods, researched the regeneration of abandoned rolled polyamide reverse osmosis membrane element.This topic is about the wasted rolled polyamide reverse osmosis membrane element by cleaning test, surface modification; make its implementation filter function. To waste film with low cost to replace the filter membrane of costly, reduce the waste quantity of reverse osmosis membrane, and reduce the environment pollution and reduce the water treatment cost, improve economic efficiency at the same time to achieve re-use of resources.According to the experimental results, the membrane element oxidized by sodium hypochlorite has better desalination and water permeability, and the oxidation time is short, so the best choice of oxidation agent is sodium hypochlorite. The optimal oxidation process parameters chosen in this experiment sodium hypochlorite: concentration 0.4%, time 60 min, temperature 30 C. From the impact of operating parameters on membrane performance analysis experiments can know, salt concentration within the range of 200 ~2000mg/L, the desalting rate decreased by 11.22%, water pressure increased by 0.02MPa; The membrane flux at 5 ~35 L/(m2·h)range, the desalting rate increased by 10.79%, the inlet pressure increases 0.16MPa; recovery rate is within the range of 8~35%, the desalting rate decreased by 7.54%, water pressure increased by 0.15MPa; the temperature within the range of 15~35?, the desalting rate decreased only 3.95%, water pressure decreased by 0.02 MPa. The recovery rate of effect on the desalination rate from high to low are salt concentration, membrane flux, changes in the operating parameters, temperature; Influence of operation parameter on the inlet pressure from big to small in order for the membrane flux, recovery rate, salt concentration, temperature. Equal salt concentrations and temperature effects on the inlet pressure, The higher the salt concentration, the higher the water pressure, but the higher the temperature, the lower the water pressure.