Waste Water

Septic tanks are mostly used in

• Urban cities

• Rural villages

• Isolated areas

• Semi-urban areas

Dried _____ is used as manure

• Slurry

• Sewage

• Sand

• Sludge

What gases are produced by anaerobic bacteria?

• Hydrogen H₂

• Carbon Dioxide CO₂

• Carbon monoxide CO

• Methane CH₄

What happens to the sewage in the first step of treatment?

• The organic matter is eaten by bacteria.

• The sewage water is aerated.

• It is screened to remove solid wastes

• It is filtered and disinfected.

We should not throw paints and greasy substances down the drain because

• they break the pipe

• they harden and clog the pipe

• they flow through the drain freely

• None of these

In which step solid waste is removed using screens in waste water treatment.

• Primary treatment

• Secondary treatment

• Tertiary treatment

What is obtained after aeration step?

• Primary sludge

• secondary sludge

• solid waste materials

Waste water from toilets is often referred to as-

• grey water

• black water

• sludge

• effluent

The process of wastewater treatment is commonly known as

• Sewage treatment

• Onsite sewage

• Wastewater

• None of these

Tags

NGSS.MS-ETS1-2

Wastewater released by houses is called_______________.

• Sludge

• Sewage

• Wastewater

• None of these