此时(shi)(shi)将过滤器内的(de)水(shui)(shui)排放到滤层的(de)上缘(yuan)为止,然后送入强度为18-25L/(m².S)的(de)压缩空气,吹洗3~5min后,在(zai)继续。 我(wo)(wo)(wo)国人均水(shui)(shui)资(zi)源(yuan)拥(yong)有(you)量(liang)只有(you)220立方(fang)米,仅为世界平均水(shui)(shui)平的(de)1/4。目前,我(wo)(wo)(wo)国黄淮河及内陆河流域有(you)11个(ge)省、区、市的(de)人均水(shui)(shui)资(zi)源(yuan)拥(yong)有(you)量(liang)低于(yu)联(lian)合国可(ke)持续发展委员会确(que)定的(de)1750立方(fang)米用(yong)水(shui)(shui)紧张线(xian),其中有(you)9个(ge)地(di)区低于(yu)500立方(fang)米严重缺(que)水(shui)(shui)线(xian)。在(zai)水(shui)(shui)资(zi)源(yuan)短缺(que)的(de)同时(shi)(shi)我(wo)(wo)(wo)国工(gong)(gong)(gong)业用(yong)水(shui)(shui)效率总体水(shui)(shui)平较低。2001年,我(wo)(wo)(wo)国每(mei)万元工(gong)(gong)(gong)业产值取水(shui)(shui)量(liang)为90立方(fang)米左(zuo)右,约为发达国家的(de)3-7倍,工(gong)(gong)(gong)业用(yong)水(shui)(shui)重复利用(yong)率约52%,远(yuan)低于(yu)发达国家80%的(de)水(shui)(shui)平。工(gong)(gong)(gong)业用(yong)水(shui)(shui)主要集中在(zai)火力发电、钢铁、石(shi)油石(shi)化、纺织和造(zao)纸5个(ge)行(xing)业。