Low-pressure desalting membranes for seawater
The Long Beach Water Department (LBWD), similar to many Southern California utilities, have been facing the issue of decreased potable water supplies. Because of its location, the City of Long Beach is ideally situated to take advantage of desalinated seawater as a source of drinking water. However, the primary barrier to seawater desalination has been its relatively high cost as compared to other available water sources. One method of reducing the operational cost for seawater desalination being proposed by LBWD is through a two-pass nanofiltration (NF) membrane process, which has the potential of lowering the overall energy required. In this configuration, permeate from the first pass is treated by the second pass membranes in order to produce potable water. This paper will present LBWD's investigation into the behavior of these lower-pressure membranes during seawater desalination.