Study On Experimental Characteristics Of High Concentration Brine Treated With Forward Osmosis Technology

Zero discharge of high concentrated brine is an inevitable requirement for sustainable development of China's environment.How to solve the problem of zero discharge of high concentration brine has seriously restricted the survival and development of some enterprises in China.It is one of the most urgent and urgent problems at home and abroad.Forward osmosis technology as a new technology of green film processing,to osmosis differential pressure as the driving force,with low energy consumption,shock resistance,simple operation and maintenance,is expected to be applied in high saline water concentration stage,meet the coal chemical industry,oil field waste-water reduction,recycling and zero emissions request.The research group of the self-made submerged membrane penetration treatment of high concentrated brine,increasing aeration is to change the conditions of the two sides of the membrane permeation fluid mechanics in the operation process by changing the drawing temperature,concentration and flow rate of raw materials and liquid liquid side side,is expected to slow down the concentration polarization and membrane fouling phenomenon of membrane process.In the two film orientations?FO mode and PRO mode?,change the draw solution concentration and temperature and from single factor experiments of fluid velocity,the evaluation index with the flux and re-flux quantity as the membrane separation performance,impact analysis,different operating conditions on the separation performance of membrane.The results showed that the flux of PRO mode FO was significantly higher than that in model,the concentration polarization phenomenon is the main factor affecting the membrane flux increased,absorbing liquid side solution temperature,can increase the diffusion coefficient of solute in the liquid absorbed,thereby effectively weaken the internal concentration polarization phenomenon.The influence of three factors on forward osmosis membrane flux via response surface analysis?DIP concentration,temperature,flow rate?analysis and forecast optimization,optimal operation conditions,the draw solution concentration is 1.47mol/L sodium chloride,the temperature is 28?,draw the liquid flow rate is 0.95 L/min,the membrane flux was 9.90 L/m²/H,and predictive value the relative error is 0.1%.In order to improve the effect of membrane fouling on membrane flux in the process of positive infiltration,the film surface aeration is adopted to improve the performance of the membrane.With the flux and pollutant retention rate as evaluation index of membrane separation performance evaluation,K⁺,Ca²⁺,SO₄^2-,ammonia nitrogen retention rate could reach 99%or more FO and PRO two models,the interception rate of Mg²⁺was above 70%,moderate aeration will effectively reduce the membrane fouling on the membrane surface,high membrane flux.Physical cleaning can restore the flux of the membrane to a certain extent and the positive permeable membrane has a strong resistance to pollution.