TÉCNICAS MODERNAS NO PROCESSO DE FILTRAÇÃO RÁPIDA DAS ÁGUAS DE ABASTECIMENTO

Abstract

The rapid sand filtration of water, considered as one of the outstanding achievements of our century, has acquired its "maturity" several years ago. In spite of that and the remarkable technical and industrial developments already attained, the design of rapid sand filters has presenteei only minor changes. In this paper the Author remarks the main changes and improvements, and points out the latest trends with respect to the rapid filtration in public water supplies. The tendcncy towards the use of coarser sand is discussed in the light of the recent knowledge on the subject. The auxiliary devices for filter washing are especially investigated, and some of the basic information with regard to their design and application is included. Special consideration is given to the question of high rates of filtration in public installations. The adoption of this new practice for economic purposes should be conditioned to some technical requirements for safety. The efforts and attempts to simplify and to reduce the cost of installationsare rapidly regarded. At the end of this part the Author indicates the convenience of more research and hopes that the dream of so many researchers will become e reality with a simple, cheap, safe and automatic filter.