As U.S. water infrastructure continues to age, it is beginning to impact water quality. Jeff Zagoudis, contributing editor for Water Quality Products, spoke with Allan Connolly, vice president of operations and engineering at Culligan, about the problem and what is being done to solve it.
Jeff Zagoudis: How would you describe the current state of water infrastructure in the U.S.?
Water Quality Products invited Joseph F. Harrison, P.E., CWS-VI, technical director of the Water Quality Association (WQA), to give an overview of current industry issues and what to expect at the upcoming Mid-Year Leadership Conference, to be held Sept. 5-7 in Nashville, Tenn.
Overcoming measurement obstacles in the desalination process
The geographically remote region around Puerto Bolívar is very arid, with desert-like conditions and little or no water available for the port’s operations.
Although the pump is a relatively small part of the overall cost of an RO system, expenses resulting from downtime and inefficiency quickly can diminish the productivity of the system and your return on investment. Due to the corrosive atmosphere and high demands on these sea water RO systems, special attention is required in the pump selection process. There are several key factors that will help to ensure optimum pump and system performance.
In 1957 The Dow Chemical Corp. addressed the negatives of using bromine by creating a brominated ion exchange resin, which opened up the use of bromine in offshore water treatment applications.2 Today, polybromide resin is used in many offshore water treatment systems. The fact that bromine can be added to water that previously has been chlorinated makes polybromide resin a practical solution to accommodate the multiple sources of water in offshore applications.
Five large municipal water agencies have combined to advocate a significantly increased federal role in encouraging desalination. The group sees desalination as a viable, cost-effective way of making seawater and brackish groundwater reliable sources to supplement national drinking water supplies.
On average there are 50 to 75 significant desalination projects per year in the United States with an average capacity of approximately 1 million gallons per day. The majority of these projects utilize membrane processes such as nanofiltration (NF) or reverse osmosis (RO).
Although China ranks sixth in the world in total water resources, there is a shortage. The average water resources per capita is 2,300 m3, making it only one fourth of the world average per capita, while the unit plantation area of water resources is only one half the world’s average value.
Groundwater resources throughout northern China are drying up at an astonishing rate.