Why does RO water purifier discharge waste water? Is this "waste water" really useless?
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Many people will be curious, why the reverse osmosis water purifier will discharge waste water? What is the difference between it and the kind of physically filtered water purifier, and what is its filtration mechanism?
Why is it called "reverse osmosis" filtration?
When the same volume of dilute solution (such as fresh water) and concentrated solution (such as salt water) are placed on both sides of the semi-permeable film, the solvent in the dilute solution will naturally flow through the semi-permeable film and spontaneously to the concentrated solution side, this phenomenon is called osmosis. When osmosis reaches equilibrium, the liquid level on the concentrated solution side will be a certain height higher than that of the dilute solution, that is, a pressure difference is formed, and this pressure difference is the osmotic pressure. If a pressure greater than the osmotic pressure is applied on one side of the concentrated solution, the flow direction of the solvent will be opposite to the original direction of penetration and begin to flow from the concentrated solution to the dilute solution side, this process is called reverse osmosis.
Simply put, it is to apply pressure to the concentrated solution through electricity, change the original direction of penetration, achieve the countercurrent of the concentrated solution, so as to purify the concentrated solution and produce pure water.
Why is waste water produced?
The core component of the reverse osmosis membrane in the working process is actually a liquid concentration process, the salt content of the water continues to increase with the water flow over the surface of the reverse osmosis membrane, and the osmotic pressure of the water continues to increase. When the osmotic pressure increases to the pressure of the booster pump, water cannot flow into the clean water end through the reverse osmosis membrane. This part of the water that does not pass through is the waste water produced when the water is made.
Is waste water really good for nothing?
First of all, with the current development of water purification technology, basically the output of a cup of pure water will be equal to the discharge of a cup of wastewater, that is, if your family can drink 3L of water a day, then this day will discharge 3L of wastewater, at first glance will feel a lot, but with our day to flush the toilet, mop the floor, laundry, washing dishes than, this water consumption is much smaller.
