Recent questions tagged water-treatment-methods

A flocculation tank used for water treatment has a velocity gradient $(G)$ of $800 \mathrm{~s}^{-1}$. The volume of the tank is $40 \mathrm{~m}^{3}$. The dynamic viscosit...

A water jet discharging from a $4 \mathrm{~cm}$ diameter orifice has a diameter of 3.5 $\mathrm{cm}$ at its vena contracta. The coefficient of velocity is defined as the ...

A sewage treatment plant $\text{(STP)}$ receives sewage at a flow rate of $20000 \mathrm{~m}^3$ per day. The sewage has $200 \mathrm{mg} / \mathrm{L}$ of suspended solids...

The characteristics of a water sample are as follows: $\mathrm{Na}^{+}=92 \mathrm{mg} / \mathrm{L}$, $\mathrm{K}^{+}=19.5 \mathrm{mg} / \mathrm{L}, \mathrm{Ca}^{2+}=40 \m...

An underground hazardous waste storage tank is leaking. The contaminant concentration directly beneath the site is $0.5 \mathrm{mg} / \mathrm{L}$. The contaminant is trav...

A $900 \mathrm{~mm}$ internal diameter sewer is laid at a slope of $0.004$ and has an actual flow of $0.15 \mathrm{~m}^3 / \mathrm{s}$. Assuming Manning's roughness coeff...

A $10$ million litres per day $\text{(MLD)}$ sewage treatment plant $\text{(STP)}$ is based on the Activated Sludge Process $\text{(ASP)}$. First, the sewage undergoes pr...

The molar concentrations $(M$, i.e. $m o l / L)$ of some ionic species in a water sample were estimated as follows:$\mathrm{Na}^{+}=0.25{\mathrm{M} ; \mathrm{Ca}^{2+}}^{2...

A facultative pond system for sewage treatment consists of two ponds in series. The hydraulic retention time $\text{(HRT)}$ of each pond is $6$ days. The total $\text{BOD...

A river water sample has $\mathrm{pH}$ of $4$ and suspended solids concentration of $100 \; \mathrm{mg} / \mathrm{L}$. If, alum is chosen as a coagulant, what will be the...

Leachate generated from a legacy municipal solid waste dumping site has to be collected and managed carefully. Which one of the following statements is correct in the con...

For effluents generated by a molasses based distillery and wood based pulp and paper industry, which of the following statement(s) is/are NOT correct?Both the effluents h...

Average values of the re-aeration rate constant for river $\mathrm{X}$ and river $\mathrm{Y}$ are $0.92$ per day and $1.12$ per day, respectively. Average de-oxygenation ...

Clean water is passed through a bed of uniform spherical sand at a filtration velocity of $0.002 \mathrm{~m} / \mathrm{sec}$. The sand grains are $0.4 \mathrm{~mm}$ in di...

A sewage treatment plant with a capacity of 10 million litres per day (MLD) is treating the sewage through an aerobic biological process. The inlet and outlet BOD are mea...

A centrifuge is processing 1000 litres per hour of water containing 2 g per litre of suspended solids. The thickened slurry coming out of the centrifuge has solids concen...