Experiences in Filtration

The purpose of this paper is to review briefly some of the past experiences in rapid filtration and to present more fully a few facts brought out in recent studies relating to the filtration of water. The limitations of the filter bed are becoming understood more thoroughly, and progress is being made in maintaining the filters in better condition than heretofore. As a result, more efficient operation of filtration plants is assured for the future. The filter operator is no longer merely a person capable of opening and closing valves in accordance with a set of instructions, who possesses little knowledge of what is taking place in the purification of the water. He is rapidly becoming a well trained person who understands the chemical reactions involved in the treatment of the water, and the hydraulic and other physical forces involved in the passage of the water through the plant. This type of person takes pride in keeping the filters operating at their maximum efficiency. Special short courses in water treatment and filtration are now being offered at so many places throughout the United States that these schools are within the reach of nearly every one engaged in water purification. It is gratifying to see so many attending such courses. Certainly these operators return to their work better qualified to perform their duties. Fuller (1) stated that little progress was made in the filtration of water in America before publication of the Kirkwood Report in 1869. For a quarter of a century this report was the leading guide on filtration practice through the description it gave of filtration plants in Europe. Fuller divided the period following the Kirkwood report into four periods. (1) The early beginning, from 1869 to 1886; (2) a period of research and development, from 1887 to 1902; (3) a period of rapid practical accomplishment, from 1903 to 1918; and (4) the period of refinement, from 1919 to 1933. The article was