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Metering Pumps for Water Treatment
Metering pumps enjoy broad application in power generation for water treatment. Water treatment occurs in at least three areas including boiler feed water; cooling water; and wastewater. Chemical treatments are required to protect the boiler, turbine, and condenser from erosion, corrosion, scale, and biological buildup, as well as for wastewater treatment in scrubbing systems. Some common treatments include hydrazine or sodium sulfite for oxygen scavenging, amines and ammonium hydroxide for pH adjustment, phosphate or calcium hydroxide to inhibit scaling, bleach or sodium hypochlorite for disinfection and microbiological control, and sulfuric acid for pH control particularly in cooling water. Other treatment regimes exist as well.
The injection flow rates for metering pumps are typically low and are measured in gallons per hour. Electric solenoid and motor-driven pumps are commonly used, with the motor-operated systems generally used for higher pressure deliveries to the boiler. Pump operating pressures can range from less than 50 psi for cooling water or wastewater treatment to 6,000 psi for direct injection of chemicals into the boiler drum. These chemical metering systems play a critical role in the overall operation of the plant.
Suppliers of chemical metering pumps to the industry include Alldos, Chongqing, IDEX, Iwaki, Milton Roy, Lutz Jesco, ProMinent, Seepex, SPX Bran + Luebbe, Watson-Marlow, and others. |
