Brackish water desalination using Reverse Osmosis
Treating brackish water with relatively low salinity for drinking water purposes requires relatively low energy consumption. The required energy for the whole process including the pump and backflush pre filtration ranges from 23,2 A (130 ppm) to 31,3 A (10400 ppm).
The following table illustrates the required energy for a number of different salinity levels:
| Feed Water salinity (ppm) | Product Water salinity (ppm) | Brine salinity (ppm) | Feed quantity (l/h) | Product Water quantity (l/h) | Brine quantity (l/h) |
|---|---|---|---|---|---|
| 130 | 5 | 2140 | 940 | 890 | 55 |
| 630 | 54 | 8000 | 905 | 855 | 55 |
| 1500 | 87 | 8000 | 910 | 775 | 135 |
| 2800 | 140 | 9400 | 910 | 670 | 230 |
| 3800 | 145 | 10200 | 910 | 615 | 295 |
| 5000 | 231 | 12000 | 900 | 535 | 365 |
| 6300 | 290 | 12200 | 900 | 455 | 445 |
| 8000 | 390 | 13200 | 900 | 375 | 525 |
| 9100 | 490 | 13000 | 905 | 330 | 575 |
| 10400 | 650 | 14700 | 900 | 270 | 630 |
DWC TBB 002 Brackish water desalination with up to 800l per hour capacity
This unit is using special reverse osmosis membranes for brackish raw water up to TDS 10.000 mg / l. Depending on te depth of the well and depending on the salinity level of the raw water it can operate with 50% recovery rate and flexible flow rate of the intake pump. That means if we set the intake pump to deliver 1000 l/h we can produce 500l per hour drinking water. The whole system including automated back flush in the pre filter unit needs about 800- 950W to operate and can be powered with 24 VDC.
- This picture shows the metal cabinet holding the pre filtration unit. You can see the two pressure tanks (red): One smaller one for automated backflushing the 100 micron and 2 x 25 micron pre filter while the other expansion tank (larger one) provides continous flow whilst the RO membranes are being flushed.
- This picture shows the actual desalination cabinet with the exclusive presure recovery system. You see on the outer left how the two boxes are connected for the water flows as well as for the controls. On the bottom of the cabinet are currently "only" two brackish RO membranes visible. The final unit will have 2 RO membranes parallel and in series making a total of 4 membranes.
