一、引言随现代城市社会经济的迅猛发展所带来的大量污水,该如何处理?向何处排放?这已成为市政建设与环境保护的紧迫任务。那些沿江沿海的城市,充分利用大水体的稀释自净能力,向江海深水排放经适度处理后的污水,已呈国际性趋势。过去20年里,美国在太平洋沿岸地区已建成了许多这样的排污工程;英国近20年来建造的这类新型排放口,据不完全统计,有30余处,排放管长度从500米到5000米,直径从150毫米到3660毫米,其中有22处排放口采用了扩散器。通常在经济发达国家,污水需经过一级、 I. INTRODUCTION With the rapid development of modern society and economy brought about by a large number of sewage, how to deal with? Where to discharge? This has become an urgent task of municipal construction and environmental protection. Those coastal cities along the river, take full advantage of the dilute self-purification capacity of large bodies of water, to the Jianghai deepwater discharge of properly treated sewage, has shown an international trend. Over the past two decades, the United States has built many such sewage projects in the Pacific Rim. The new type of new vent built in the United Kingdom in the past 20 years, according to incomplete statistics, has more than 30 locations and discharge pipe lengths from 500 to 5,000 meters , From 150 mm in diameter to 3660 mm in diameter, of which 22 diffusers are used for venting. Usually in economically developed countries, sewage needs to go through a level,