Patent ID: 6355145
Filing Date: 2002-03-12
Classification: B01D,C02F,Y02P,Y10S

Abstract:
A method of removing contaminants from a water feed stream containing contaminants by combining vapor compression and a forced circulation circuit, comprising the steps of:preheating a water feed stream in a first step to at least partially remove some of said contaminants from said waterfeed stream and recover energy from a concentrate and distillate; heating the preheated water feed stream in a second heating step in a heated separator to generate a vapor fraction and a concentrate liquid contaminant fraction; compressing said vapor fraction to generate a temperature differential in a reboiler exchanger; controlling the temperature differential within said reboiler exchanger and the concentrate temperature to maintain nucleate boiling whereby a wetted surface is maintained within said reboiler exchanger; circulating at least a portion of said concentrate through said reboiler exchanger and said heated separator; maintaining a ratio of circulating mass to vapor mass of between 300 and 2 to maintain wetted surfaces on heated surfaces of said heated separator and said reboiler exchanger for reducing scale formation and fouling said ratio resulting in a vapor fraction of between 1% and 50% by mass vapor exiting said reboiler exchanger; condensing the vapor fraction and collecting a distillate; and removing at least a portion of said concentrate from said reboiler to reduce the level of said contaminants.