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Wastewater Story — Science STD 7 — Question

Gujarat BoardEnglish MediumSTD 7ScienceWastewater Story3 Marks
Question
What is sludge? Explain how it is treated.
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Answer

Semi-solids such as faeces that settle down during wastewater treatment are called sludge. This sludge is removed using a scraper and then transferred to a tank where it is decomposed by anaerobic bacteria to produce biogas. This biogas is used as a low-cost fuel for heating, cooking, etc. It is also used to produce electricity.

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