During denitrification, nitrate is reduced to nitrogen gas which can escape to t

Question

During denitrification, nitrate is reduced to nitrogen gas which can escape to the atmosphere. You are considering building a suspended solids reactor (activated sludge type) for denitrification of 30mg/l of NO-N. Nitrate is the nitrogen source for cell synthesis.

The energy equation for the reaction is:

6NO + 5CHOH ---> 3N + 5CO + 7HO + 6OH

The synthesis equation for the reaction is: NO + organic carbon ---> NO + organic carbon ---> N + CO + HO

A.) Assuming fs = 0.4, write a balanced equation for the overall reaction (normalize to one mole of NO).

B.) Estimate the quantity of acetic acid in mg/l requried for nitrate reduction (assume 1mg/l NO-N remains in the treated effluent).

Explanation / Answer

A.) Assuming fs = 0.4, write a balanced equation for the overall reaction is

NO + 5/6CHOH ---> 1/2N + 5/6CO + 7/6HO + OH (normalized to one mole of NO).

B.) To estimate the quantity of acetic acid in mg/l requried for nitrate reduction

usually 1mole of NO required 5/6 mole of acetic acid for reduction process.

i.e. 62 g of NO required 50 g of acetic acid for reduction process. Here, mass of acetic acid= 60 g/mol)

Now, assume 1mg/l NO required 0.8064 mg/l of acetic acid for reduction process.

Related Questions

Navigate

• Browse (All)
• Browse D
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.