Removal of Taste and Odor from Municipal Water Supplies

Abstract

Since the spring of 1931 the Ontario Department of Health has conducted an extensive experimental investigation into the problem of tastes and odors in municipal water supplies. The results accomplished are summarized in tables 1 and 2. Laboratory and plant-scale experiments were performed. The success of each treatment is shown by the sign affixed. Plus indicates that the treatment was successful; minus, that no good was accomplished; and plus-and-minus, that only partial improvement was obtained. At Chatham chloramine was effective in preventing algae growth, and thereby also was effective in reducing the taste to a considerable extent. At Wallaceburg chloramine prevented the formation of the taste-producing chlorphenol by reducing the activity of the chlorine. The details of these two experiments will be given by others. They illustrate the two uses of chloramine treatment; first, in preventing taste by preventing algae growth, and second, in preventing the formation of taste producing substances by reducing the activity of chlorine. Chloramines cannot be expected to remove tastes already present in the water. The use of granular activated carbon received considerable attention at Chatham, Haileybury, Kirkland Lake, Lindsay, and Timmins. The carbon was used in the form of small filter beds through which water was passed. The amount of water obtained before a noticeable taste was secured was not large. At Chatham the experiment was discontinued before the carbon was saturated. At Haileybury the filter was used only during short periods of extremely offensive taste. At Kirkland Lake and Timmins, unfiltered water was used. This probably reduced the life of the carbon. At Timmins, color was removed as well as taste and odor. At Lindsay, clear and colorless tap water was used. The yield of tasteless water was 18,000 gallon per cubic foot. This is evidently too low to make