CVEN 5534

Spring 2008

Assignment 1, Due Tuesday, Jan 22

A municipal wastewater treatment plant receives 70 m3/min average flow containing 250

g/m3 soluble/colloidal organic matter measured as carbonaceous oxygen demand (COD),

which has units of g/m3 oxygen. Approximately 95% of the COD is removed from the

treated wastewater. Of the fraction removed, 75% of the COD is oxidized by bacteria to

CO2 and 25% is incorporated into bacterial biomass.

a. What is the mass flow rate of oxygen (kg/day) that must be supplied?

b. What is the yearly emission of CO2 (kg/yr) from the plant. Compare this to the

emissions from a 200 MW power plant.

c. What is the biomass generation rate (kg/year) if the chemical for bacterial cells is

C5H7NO2?