Reverse Osmosis With Pressure Exchangers
One application in which pressure exchangers are widely used is reverse osmosis (RO). In an RO system, pressure exchangers are used as energy recovery devices (ERDs). As illustrated, high-pressure concentrate from the membranes is directed to the ERD . The ERD uses this high-pressure concentrate stream to pressurize the low-pressure seawater stream (stream becomes stream ), which it then merges (with the aid of a circulation pump ) into the highest-pressure seawater stream created by the high-pressure pump . This combined stream feeds the membranes . The concentrate leaves the ERD at low pressure, expelled by the incoming feedwater flow .
Pressure exchangers save energy in these systems by reducing the load on the high pressure pump. In a seawater RO system operating at a 40% membrane water recovery rate, the ERD supplies 60% of the membrane feed flow. Energy is consumed by the circulation pump, however, because this pump merely circulates and does not pressurize water, its energy consumption is almost negligible: less than 3% of the energy consumed by the high pressure pump. Therefore, nearly 60% of the membrane feed flow is pressurized with almost no energy input.
Read more about this topic: Pressure Exchanger
Famous quotes containing the words reverse and/or pressure:
“Now listen, buddy, there are a few corny ideas you got to get out of your head if you’re going to fly an airplane. Most things are just the reverse from what people think. The higher you are the safer you are. The Earth down there, that, that’s your enemy because once you hit that, boy, you splatter.”
—Dalton Trumbo (1905–1976)
“I am convinced that our American society will become more and more vulgarized and that it will be fragmentized into contending economic, racial and religious pressure groups lacking in unity and common will, unless we can arrest the disintegration of the family and of community solidarity.”
—Agnes E. Meyer (1887–1970)