High recovery in the Yuma desalting plant

The 363 400 m 3 /d capacity Yuma Desalting Plant has been designed to operate using membrane desalting at about 70 percent product water recovery with the remaining 30 percent being wasted reject brine. An engineering feasibility study was undertaken to identify the best methods of achieving higher recoveries and thus of reducing the brine volume. Results indicate that 90 percent recovery can be attained most economically by increasing the membrane area by roughly 50 percent through additional desalting equipment and by better pretreatment removal of calcium and silica through use of partial lime softening- clarification followed by additional ion-exchange softening. Reject desalting brine would regenerate the ion exchangers. A test program is underway intended to develop this approach and to provide the required design data should it be decided later to alter the Yuma Desalting Plant for high recovery.