Evaluation of Ion Exchange Softening on the Leaching of Metals from HouseholdPlumbing Materials

摘要

A 16 month pilot plant study was conducted to determine the effect of ionexchange softening on the leaching of metals from household plumbing materials. Two pipe loop pilot plant systems were assembled. Each system consisted of duplicate loops of lead pipe, copper pipe with 50:50 lead-tin soldered joints, copper tubing, galvanized pipe, and brass faucets. The source water had a pH of about 9 and a hardness of about 160 mg/L as CaCO3. One system (control) was fed non-softened water and the second system (test) ion exchange softended water. It was concluded that there was no consisted pattern of higher metal levels from the softened water leading to the general conclusion that the softened water was not more corrosive to the plumbing materials than the non-softened water with the water quality used for this study.