Glossary

A dictionary of desalination terms.

waste heat evaporator

An evaporator that uses the heat of a gas turbine, diesel engine jacket water, or exhaust gas.

Water Factory 21

An Orange County, California treatment plant designed to produce high quality water from municipal wastewater for injection into aquifers, creating a coastal barrier and preventing sea water intrusion of underground water supplies.

water for injection

(WFI) Water purified to USP standards by distillation, ion exchange or other suitable process, containing no additives, and intended for use as a solvent for preparation of parenteral solutions.

Water Purchase Agreement

(WPA) A DBOOT contract is often referred to as the WPA. A WPA is a long-term water supply agreement between a contractor and offtaker which may be part of an IWP or IWPP.

water purveyor

An agency or person that supplies water.

water reclamation

The restoration of wastewater to a state that will allow its beneficial reuse.

water reuse

The beneficial use of reclaimed water such as irrigation, cooling or washing.

Water Tariff

The Water Tariff defined is the cost the offtaker will pay for provision of a specified water quantity and quality. The tariff may include a fixed component to cover the capital expenditure and fixed O&M costs, and a variable component to cover energy costs and variable O&M costs. The offtaker may have the option of purchasing additional water at a lower, ‘commodity charge’ rate.

water vapour

The gaseous form of water.

water-soluble

The description of a material that dissolves in water.

waterbox

The chamber at the inlet end of a condenser tubesheet.

watermaker

A common term for a packaged, vapour compression thermal desalination unit.

weak acid

A poorly ionized acid that dissociates very little and produces few hydrogen ions in aqueous solution.

wet bulb temperature

The temperature reading taken from a thermometer with a wetted wick surrounding its bulb.

work exchanger

A mechanical energy recovery device where the energy of one fluid stream is transferred to another fluid.

WPA

Water purchase agreement.

WSTA

Water Science and Technology Association.