采用双层和多层滤料滤池并配合投加有机高分子电解质以控制絮体穿透的工艺始于美国和苏联,现已日益引起世界各地的兴趣。在瑞典,近几年来对过滤技术进行了研究。在比利时,对直接过滤进行了一系列小型试验,包括双层和三层滤料。英国某水厂的生产运行情况, The use of double- and multi-layer filter media and the addition of organic polymer electrolytes to control floe penetration began in the United States and the Soviet Union, and has now increasingly attracted worldwide interest. In Sweden, filtration technology has been studied in recent years. In Belgium, a series of small tests were conducted on direct filtration, including two- and three-layer filters. Production and operation of a water plant in the United Kingdom,