Desalination is a Growth Market for Flow Control and Filtration
The 2013 market for flow control and filtration equipment and consumables for desalination will exceed $5.7 billion according to the latest aggregated forecasts in McIlvaine market reports.
The major market has been the Middle East but other areas of the world are finding that desalination is a viable alternative. The most recent example is in San Diego where Poseidon Resources has landed a contract to build a 50 million gallon/day desalination plant. This will be the largest in the western hemisphere.
The amount of water being pumped in desalination systems is presently only about one percent of the amount being pumped for all the world s drinking supplies. On the other hand, the high pressure pumps needed for reverse osmosis are an order of magnitude more expensive than those used for drinking water transport. Prefiltration for the reverse osmosis systems and initial purification of water which will be evaporated in thermal systems is accomplished with liquid macrofiltration and cartridges. Automatic back wash filters and sand filters are frequently used. Liquid wastes are dewatered in filter presses.
Cartridges are used to remove particles which are too small to be captured in liquid macrofiltration equipment, but too large and plentiful to be handled by cross-flow membranes. There has been a high replacement frequency on cartridges.
An alternative to liquid macrofiltration is sedimentation. Clarifiers and dissolved air flotation systems are selected for a number of systems. The desalting takes place in either thermal systems where the water is evaporated or by separation with cross-flow membranes. Reverse osmosis (RO) does the final separation. Macro or ultrafilters are often used to pre-filter and protect the RO membranes.
Picture: McIlvaine
Source: The McIlvaine Company
