1998 Volume 23 Issue 5 Pages 226-228
A large 40, 000 m3/day plant, which has been inaugurated recently at Okinawa, is introduced. The reduction of boron concentration in the permeate of the RO seawater desalination units is discussed. The trend of application of the high pressure RO to a high-recovery seawater and a landfill leachate desalination processes is explained.
The nanofiltration has become an inportant purification process for treating the drinking water sources. However, the commercial membranes are too numerous that it is important to qualify them properly.
The various unique UF and MF modules, developed at the Aqua-renaissance '90 project, are now used for the high-recovery drinking water treatment processes.
The acid and alkali recovery processes, which use ion-exchange membranes, namely, dialysis, electro-dialysis and electrolysis processes, are introduced. The ion-exchange process, where resins are regenerated not by acid or alkali but by using ion-exchange membranes are finally introduced.
