Flowchart of clean water treatment technology by RO . membrane method

Figure 1: Flowchart of clean water treatment technology by RO . membrane filtration method

Technology Description:

–     Source water will be preliminarily treated by settling works, sand filter tanks to settle large-sized particles.

–     Raw water after primary filtration by a system of sand filter tanks and protective filter columns to remove small particles, will be thoroughly treated by RO filter core.

Figure 2: RO . membrane structure

–     RO membranes have a membrane pore size of about 0.001 – 0.0001 Micron; consists of several thin layers or sheets of film that are fastened, rolled together and in a spiral configuration around a plastic core. Membrane materials have a special structure that allows water molecules to pass through, but not dissolved solids (e.g., chemically contaminated minerals).

–     When the filter core is maintained under sufficient pressure, water molecules penetrate horizontally along the membrane surface, around the spiral surface move along the clean water pipe to the water tank after treatment. Other pollutants from the surface of the membranes are pushed out by the discharge route.

Advantages:

–     The system for water quality after treatment completely removes bacteria and dissolved components contained in water.

Defect:

–     The operation system is complicated, especially the preliminary treatment of source water before the final treatment with RO membrane.

–     High operating costs:

+    Due to the high operating pressure of the RO membrane, resulting in high pump pressure requirements.

+    High cost of maintenance and replacement of RO membranes, due to low membrane durability.

+    The pump chute details are used and the pipeline deteriorates quickly due to always having to operate at high pressure of about 400 PSI (Approx. 27.57 Bar)

–     Purified water from RO filtration technology often does not retain natural trace minerals that are good for the body such as calcium, magnesium… Using purified water for a long time is not good for health. Therefore, if you want to use this water for drinking purposes, you need to add a mineral compensation filter system.

–     Because the RO membrane filtration method is reverse osmosis, the finished water will usually be less than the discarded water (For example, if you want to treat 200 m3 of clean water, you need about 400 m3 of raw water).

–     The water after treatment does not retain the minerals necessary for the health of the user.

Scope of application:

–     RO membrane is used to filter seawater, or used to filter water for cooling systems that require high water quality.