Dewvaporation Desalination 5,000-Gallon-Per Day Pilot Plant. Desalination and Water Purification Research and Development Program Report No. 120; Final rept. for Oct 07-Jan 08

摘要

A 5,000-gallon-per-day dewvaporation pilot plant was designed, built, and operated at the 23rd Avenue Waste Water Treatment Plant (WWTP) in Phoenix, Arizona. The City of Phoenix Water Services Department, along with the Bureau of Reclamation Phoenix Area Office, cooperated to establish a pilot plant site. The pilot plant feed was the concentrate from a Tactical Water Purifier System reverse osmosis (RO) unit with ultrafiltration pretreatment. A 2,000-milligram-per-liter (mg/L) total dissolved solids (TDS) waste water RO concentrate stream was treated by the pilot plant to more than 45,000 mg/L of TDS brine and 10 mg/L of TDS distillate. Recovery varied from 70 percent to 100 percent, with no decrease in distillate rate or increase in distillate contamination. Thermal multiple effects varied from 2.0 to 3.5, which was less than the 5.0 effects demonstrated prior to transport to the WWTP site. Operating cost was highly dependent of the price of fuel. Using the average of the three best thermal multiple effect values of 3.2 and natural gas cost of $0.80 per therm, the operating cost of water would be $20.85 per 1,000 gallons. The use of waste heat or solar thermal would reduce the operating cost to the cost of water pumping and air blowing. Power needs of 0.5 kilowatthour (kWh) per 1,000 gallons at $0.10 per kWh would amount to $0.05 per 1,000 gallons.