Oxygen

Question 1

Define biological oxygen demand (BOD) of water

Answer 1

BOD is the amount of oxygen required by a microbe to break down organic material at a specific temperature over a period of time.

Question 2

explain the procedure to measure

the standard BOD5 test in a laboratory.

Answer 2

Add wastewater sample to bottle of water (V=300ml)
Measure BOD at t=0
Incubate at 20 degree C for 5 days
Measure BOD at t=5
BODt=(DO-DOf)*Vbottle/Vsample

DO-DOf should be > 2mg/l
DOf > 1mg/l