Draining is to keep the boiler water alkalinity within certain consistence and requires of the boiler water standard. And in the same time it also drains out boiler water's aggradations.

排污是使炉水碱度不超过一定的浓度，符合炉水碱度要求，同时排出炉水沉积物。

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The waste water discharged from textile printing and dyeing enterprise has strong alkalinity, can be used to desulphurize smoke and vapour exhausted directly from coal burning boiler.

而纺织印染企业排出的工业污水呈强碱性，可直接用于锅炉烟气脱硫。

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