Given below is a jumbled sequence of the processes involved in a wastewater treatment plant. Arrange them in their correct sequence. (a) Sludge is scraped out and skimmer removes the floating grease. (b) Water is made to settle in a large tank with a slope in the middle. (c) Large objects like plastic bags are removed by passing wastewater through bar screens. (d) Sand, grit and pebbles are made to settle by decreasing the speed of incoming wastewater. (e) Wastewater enters a grit and sand removal tank.
ScienceClass 7CBSEAnswered 27 Mar 2026
Answer
Soln:
(c) Large objects like plastic bags are removed by passing wastewater through bar screens.
(e) Wastewater enters a grit and sand removal tank.
(d) Sand, grit and pebbles are made to settle by decreasing the speed of incoming wastewater.
(b) Water is made to settle in a large tank with a slope in the middle.
(a) Sludge is scraped out and skimmer removes the floating grease.
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