Double stage reverse osmosis is the process of adjusting the pH value of the permeate from the first stage reverse osmosis, and then sending it to the second stage reverse osmosis system for treatment by the second stage high-pressure pump, in order to obtain permeate. The desalination rate of the first stage reverse osmosis system is ≥ 99.5%. In this way, raw water with a salt content below 1000ppm can be directly treated without ion exchange to meet the physical and chemical indicators specified in the GB1732-1998 bottled drinking purified water standard.
