Treat saline water with the innovative RO technology

31, tháng 01, 2023

Currently, the surface water is salty in dry seasons, which causes some provinces in the Melkong Delta face challenges to provide clean water to the citizens. Some wells have been exploited for a long time, brackish water (with chloride content > 250 mg/l) in deep and coastal layers has been pulled into wells, causing the decreasing water quality and  the unmet drinking water standards of the Ministry of Health.

Previously, when using traditional RO systems to improve water quality, the output clean water efficiency was very low (50/50). For instance, when pumping into the system 100 m3/hr, only 50 m3/hr is obtained. The input pressure will be large (about 12 bar), so the energy consumption is also huge, leading to the increase of operating cost.

To solve this problem, DNP Hawaco has used innovative RO technology – the most modern and largest system in Vietnam’s water industry. The technology is applied to Phu Loi Water Supply Enterprise, Ward 2, Soc Trang city and gave good results:

  • The output clean water efficiency is quite high (80%). For example, if the inlet flow is 100 m3/hr, the wastewater (concentrate) output is only 20 m3/hr, and the clean water (permeat) output is 80 m3/hr.
  • The quality of treated water is stable and meets the requirements of QC 01/2009 BYT.
  • Operation tasks are not complicated, fully automatic, low management and operation costs.
  • Especially less maintenance as well as low investment costs due to the application of anti-scalant, the filter life will be twice as long as that of traditional RO systems.

Water quality of Phu Loi RO system:

Criteria Unit Input of RO system Output of RO system
Capacity m3/h 160 128
Fe mg/l 0.23 0.01
Cl- mg/l 683 24
CaCO3 mg/l 107 0
NH4+ mg/l 0.52 0.02
Mn mg/l 0.05 0.015
pH mg/l 7.86 6.72


(Water quality tested on 13/07/2017 provided by Soc Trang Water Supply Company Limited)

DNP Hawaco pioneers in providing technological solutions, equipment and materials for the water – environment – irrigation industry.