2 Questions for Quiz 1 - Engineering Application in Biosystems | BAE 2012, Quizzes of Engineering

Download 2 Questions for Quiz 1 - Engineering Application in Biosystems | BAE 2012 and more Quizzes Engineering in PDF only on Docsity! BAE 2013 Quiz 1 Name: ____KEY________ Note: Answer both questions – write legibly. Good luck! 1. [ 3 points] a. What is the define the biochemical oxygen demand (BOD) BOD is the amount of oxygen required by microorganisms to decompose a certain amount of organic waste. [ 2 points] b. Write two reasons for doing BOD tests. • approximate quantity of O2 that will be required to biologically stabilize the organic matter present • effectiveness of wastewater treatment plants • size of waste treatment facility • compliance with wastewater discharge regulations 2. [ 5 points] Calculate the BOD5 of a river stream from which a sample was taken and a BOD test was performed. The initial and final (after 5 days) dissolved O2 concentrations in the bottle containing sample and dilution water were 8.45 mg/L and 1.45 mg/L, respectively. The sample size was 5.00 mL and total volume of sample and water was 300 mL. Hint: s b fi V V DODOLmgBOD )(/,5 −= mg/L 420 ml 5 ml 300 )mg/L 45.1mg/L 45.8(/,5 =−=LmgBOD