Author：Huamo Water treatment materials FROM：Water filter membrane manufacturer TIME：2021-12-03
Fully grasp the harm of other index values of ro membrane element in the system software to its characteristics, which is beneficial to the design of a more scientific reverse osmosis system. In the entire process of practical application, try to avoid the adverse effects of these factors on ro membrane element harm.
2. Utilization rate. If the utilization rate is increased, the residual salt content in the raw water will be higher. Of course, the osmotic concentration will continue to increase until it is the same as the increased pressure, which may offset the promotion of the inlet water pressure, ease or even stop the entire process of RO reverse osmosis, and further increase the scaling caused by the tendency of salt to deposit on the membrane surface. problem. Therefore, the increase in the utilization rate will reduce the water production and the desalination rate.
3. Temperature. Ro membrane element is very sensitive to changes in the system inlet water temperature. The temperature of the inlet water increases, resulting in a decrease in the viscosity of the water passing through the membrane and an increase in the transmission capacity. Therefore, as the temperature increases, the water flux basically expands linearly, and the salt permeability will also increase. Therefore, the higher the inlet water temperature, the greater the water production, and the lower the salt rejection rate. On the contrary, the lower the temperature, the smaller the water production, but the higher the salt rejection rate. This is the reason why the water production of RO products decreases in winter and the amount of sewage increases, but the effluent body is relatively high at this time.
4. Salt content. The index value of the water inflow may endanger the osmotic concentration. The osmotic concentration is the concentration value of the salt or organic compound in the water and the number of culverts of the type. As the salt content increases, the osmotic concentration increases (compares with the inlet water pressure). Under the circumstance of constant water production, the impulse of water inflow that reverses the direction of osmotic fluidity will also increase at the same time. When the pressure remains stable, the higher the influent salt content, the lower the flux, and the salt flux through the membrane increases.
5. Water inlet pressure. The inlet water pressure (referring to the reasonable pressure deviating from the osmotic pressure) may endanger the production water flux and desalination rate of reverse osmosis element membrane. Membrane separation technology is based on the actual operating pressure that increases in the water inlet direction to break away from the natural osmotic pressure. When the actual operating pressure of the concentrated solution is higher than the osmotic concentration, the flow direction of the natural permeation of water may be reversed, and the concentrated solution may become filtered water in terms of dilute solution according to the membrane.