AWWA WQTC69244

Advances in chemical feed equipment provide options for cost-effective alkalinity addition thatwere previously unavailable. In the past, carbon dioxide systems required deep basins and asignificant amount of reaction time to achieve stable water. Solution carbon dioxide feed systemsallow for instantaneous dissolution of "liquid" carbon dioxide and provide a means fordepressing the pH in an inexpensive and safe method which when used in combination with limeaddition can allow utilities to "dial-in" both the optimal pH for coagulation as well as provide asignificant increase in presoftened, coagulated, and finished water alkalinity. Carbon dioxideaddition in combination with lime prior to coagulation allows additional buffering capacity in thecoagulation process to minimize basin corrosion while providing an optimal enhancedcoagulation pH. Lime or caustic addition prior to media filtration or after membrane filtrationallows the shift in the carbonate species and stabilizes the water quality. Improved technology,which provides faster reacting lime slurry allows for addition of lime after filtration, withoutsignificantly impacting the turbidity of the finished water (depending on the water quality). Includes tables.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

7

File Size:

1 file , 730 KB