Subject :NSO Class : Class 7
How is bacteria usually used in sewage treatment?
ABacteria is used to speed up digestion of waste
into harmless soluble substances.
BBacteria is used to remove pathogens in sludge
before the latter is released into water bodies.
CBacteria is used to help heavier waste to settle
for removal in sedimentation tanks.
DBacteria is used to sterilise sludge to ensure safe
discharge into rivers and lakes.
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Class : Class 7