Brackish water contains lots of neural salt, has higher alkalinity than hardness with its PH greater than 7.
The Filtration Process of Brackish Water
Raw water → Primary Treatment (Micro-filtration) → Secondary Treatment (Ultra-filtration) → Reverse Osmosis (RO) → Purified Water
1. Primary Treatment (MF)
In this step, the sand and some large suspended solids in the raw water are removed. In order to protect the following filter systems, Hongtek High Flow Cartridges, String Wound Cartridges and Melt Blown Cartridges could be applied. Among these, High Flow Cartridge is the hottest one with 40 inches in length and 5 microns in filtration precision. Furthermore, in order to address the needs of users, the size can be customized.
2. Secondary Treatment (UF)
After primary treatment, most of the pollutants still remain to be settled, such as bacteria, molds, viruses, etc. In this step, if allow the water flow through the RO filter directly, the RO system would suffer from clogging the membrane. In this case, secondary treatment is adopted to remove the remains. By this, the service life of RO membrane can be further improved, thus the cost of filtration can be reduced.
3. Reverse Osmosis (RO)
In the last step, not only the residual colloidal particles, bacteria and viruses, but also the ionic species are removed by RO treatment. After that, the brackish water is desalinized.
If the SDI of inflow and recovery of brackish water too high, the RO membrane would suffer irreversible pollution and its service life would be shortened. Therefore, MF and UF systems play a critical role as a pretreatment prior to RO.