sodium bisulphate sodium thiosulphate sodium sulphate sodium hexametaphosphate
Answer Discuss in Comment
B.O.D. dissolved oxygen content organic matter content ammonia content
horizontal velocity of water length of the tank depth of the tank detention time
clogging of pores in soil due to excessive application of sewage to land, obstructing aeration and leading to septic conditions destruction of aquatic flora and fauna due to gross pollution of receiving bodies of water by sewage toxicity of sewage interfering with response to treatment reduction in the waste purifying capacity of the soil
their construction is economical they offer good flow velocity during their maintenance is easier they are structurally more stable
restrict the flow of water prevent entry of foul gases in the house provide a partial vacuum trap the solid wastes
natural or artificial depressions exist adequate depth of cover material is available at the site the water table is near the surface area is unsuitable for excavation of trenches
hydraulic gradients of the sewers crowns of the sewers inverts of the sewers bottom of the concrete bed of sewers
oceans lakes rivers wells
aerobic anaerobic facultative any of the above
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