Evaluation of Ion-Exchange Pretreatment for Membrane Desalting Processes,

摘要

Testing and evaluation of ion-exchange softening as a pretreatment for membrane desalting processes was conducted at the Office of Saline Water, Dalpra Test Station, Longmont,Colo.,from April 1971to December 1973. Effort was directed to determining economical softening techniques for membrane desalting plant feed waters. Softening objective is to eliminate calcium scaling which normally occurs in the concentrated brine stream. This permits higher product water recovery. Higher product recovery means higher yields of useful water and smaller quantities of waste brine which ultimately must be disposed of. An appraisal of other potential feed waters showed that not all waters contain sufficient sodium to make waste brine softening possible. In the Colorado River Point Source Salinity Control Program, Welton Mohawk and La Verkin Springs appear to have enough available sodium while Las Vegas Wash does not.