Assignment #1

Round answers to an appropriate number of digits and include proper units.

A labelled diagram is required for each question.

Answer the following problems, providing details on all calculations. The #, ##, ### or #### will represent the LAST 1,2,3 or 4 digits of your student number. 000837359

 

Question 1) Air Pollution Mass Balance 

The City of A is approximately 25 km (width) by 40 km (length). The average wind speed is 15 kph from the northwest and flows through an altitude of approximately 1 km. If the average annual particulate concentration in the city is 57 ug/m3, what is the annual quantity of pollutants discharged into the air above the City of A? (Report final answer in tonnes per year) Assume the concentration of particulates coming into Hamilton is ‘0’; and accumulation of particulates is 37359 kg/d. Use a block diagram to illustrate your work.

 

Question 2) Dissolved Oxygen in Water

An industrial WWTP discharges into a large river 0.42 m3/s of industrial effluent with an ultimate BOD concentration of 273 mg/L and a D.O. concentration of 1.9 mg/L at a temperature of 20∘C. The velocity of the river is 0.75 m/s. Upstream of the point of discharge, the river has a temperature of 8∘C, an ultimate BOD of 17 mg/L and a flow rate of 5.1 m3/s. Use a diagram to illustrate the problem. State all assumptions.

 

Calculate:

• the DO concentration at the point of discharge
• the DO deficit at the point of discharge
• the ultimate BOD at the point of discharge