The waste water treatment plant located in Lawrence, KS uses sodium hypochlorite for effluent disinfection and replaced three one-year old diaphragm-metering pumps, which required extensive maintenance, with our 620 range of metering pumps.
Due to the corrosive nature of sodium hypochlorite and the tendency to off-gas the diaphragm pumps would stop pumping and vapor lock causing expensive plant downtime. Based on this success with the Watson-Marlow 600 series tube pumps, the city directed their engineer to include Watson-Marlow's series tube pumps for new chemical feed facilities including sodium hypochlorite, ferric chloride and sodium bisulfite.
Another area of the plant that was under improvements was their polymer feed system. Progressive cavity (PC) pumps were originally designed and installed, however because of polymer incompatibility the stators on the PC pumps required continual replacement. The city tried several different stator materials but none of them lasted very long, which resulted in expensive spare parts and maintenance costs.
Unlike the PC pumps, the polymer only comes in contact with the Watson-Marlow tubing. Not to mention it is a lot less expensive to replace a piece of tube than a PC stator. The city elected to replace all the PC pumps with Watson-Marlow 600 series tube pumps.
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