Principles Of Operation - GE Osmonics E4H Series Operation And Maintenance Manual

Some operating definitions are provided to help you further understand your machine:
Permeate Rate [Product Water Rate (Q
passed through the membrane element and out of the membrane element housing;
expressed in gal/min (gpm) or gal/hr (gph) [in metric, liter/min (Lpm) or cubic
3
meters/hour (m /h)]. Specified permeate rates are normally at 77ºF (25ºC).
Concentrate Rate [Waste Water Rate (Q
ed solids to drain in gpm or gph (Lpm or m
Feed Rate (Q ) is the flow rate of incoming water in gpm or gph (Lpm or m
f
Feedwater rate equals permeate rate plus concentrate rate.
Recovery equals permeate rate divided by feed rate and is expressed as a percentage.
For example, 33% recovery means that out of a given feed rate, 33% is produced as
purified water (permeate).
Concentration equals the Total Dissolved Solids (TDS) concentration of a solution
expressed as milligrams per liter (mg/L) or conductivity (microSiemens/cm).
C
f
C
p
C
c
C
avg
Salt (Ionic) Rejection equals the percent of dissolved salt rejected by the membrane
element, calculated from an average concentration over the membrane.
Salt (Ionic) Passage equals (100% - rejection) or the percent of dissolved salts passed
through the membrane element.
An example of how to calculate salt rejection and recovery is given below:
)] is the flow rate of purified water which has
p
)] is the flow rate of water containing reject-
c
3
/h).
= Feed Concentration
= Permeate Concentration
= Concentrate Concentration
= Average Concentration in Machine
Figure 1.4

Principles of Operation

3
3
/h).