Water problems in the future will become more intense and more complex. Our increasing population will tremendously increase urban wastes, primarily sewage. On the other hand, increasing demands for water will decrease substantially the amount of water available for diluting wastes. Rapidly expanding industries which involve more and more complex chemical processes will produce larger volumes of liquid wastes, and many of these will contain chemicals which are noxious. To feed our rapidly expanding population, agriculture will have to be intensified. This will involve ever-increasing quantities of agricultural chemicals. From this, it is apparent that drastic steps must be taken immediately to develop corrective measures for the pollution problem.
将来水的问题会变得更加尖锐复杂。不断增长的人口将大量增加城市废物,主要是生活污水。另一方面,用水需求的不断增长将使得可用于稀释废水的水量大大减少。快速发展的工业越来越多地采用各种复杂 的化学方法,从而使废水大量增多,而很多废水中含有种种有害的化学 物质。为了养活迅速增长的人口,农业必须集约化,这就会不断增加农 用化学品的用量。由此看来,必须立即采取果断行动研究污染问题的整治措施。
There are two ways by which the pollution problem can be dwindled. The first relates to the treatment of wastes to decrease their pollution hazard. This involves the processing of solid wastes prior to disposal and the treatment of liquid wastes, or effluents, to permit the reuse of the water or minimize pollution upon final disposal.
整治污染问题的方法有两种。第一种是通过废物处理减少污染的危害,包括固体废物排放? 之前?的处理和液体废物或污水的处理,从而实现水的循环利用或者尽量降低最终排放前的污染程度。
A second approach is to develop an economic use for all or a part of the wastes. Farm manure is spread in fields as a nutrient or organic supplement. Effluents from sewage disposal plants are used in some areas both for irrigation and for the nutrients contained. Effluents from other processing plants may also be used as a supplemental source of water. Many industries, such as meat and poultry processing plants, are currently converting former waste products into marketable byproducts. Other industries are exploring potential economic uses
第二种方法是开发全部或部分废物的经济利用。农田中施用农家肥 补充肥分或有机肥。有些地区使用污水处理厂排放的污水进行灌溉施肥。其他水处理厂排出的废水也可用作补充水源。现在,禽肉加工等许 多行业正在把原先废弃的下脚料加工成可供出售的副产品,其他行业也在研究废弃物的经济利用可能途径。
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