ENVIRONMENTAL ENGINEERING - QUESTION 22.2 : Biochemical Oxygen Demand (BOD) could be calculated using the formula BOD = (DOi - DOf) (Vb / Vs) where Vb = Volume of bottle in ml, Vs = Volume of sample in ml, DOi = Initial dissolved oxygen in mg / L, DOf = Final dissolved oxygen in mg / L. (a) By using a bottle of Vb = 300 ml with sample Vs = 30 ml, find the BOD if DOi = 8.8 mg / L and DOf = 5.9 mg / L. (b) By using a bottle Vb = 600 mL with sample Vs = 100 mL, find the BOD if DOi = 8.8 mg / L and DOf = 4.2 mg / L. (c) Find the average BOD = [ Answer of (a) + Answer of (b) ] / 2. (d) If the BOD-5 test for (a) - (c) is run on a secondary effluent using a nitrification inhibitor, find the nitrogenous BOD (NBOD) = TBOD - CBOD. Let TBOD = 45 mg / L and CBOD = Answer of (c).
Answer Posted / kangchuentat
ENVIRONMENTAL ENGINEERING - ANSWER 22.2 : (a) BOD = (8.8 - 5.9) (300 / 30) = 29 mg / L. (b) BOD = (8.8 - 4.2) (600 / 100) = 27.6 mg / L. (c) BOD = (29 + 27.6) / 2 = 28.3 mg / L. (d) NBOD = 45 - 28.3 = 16.7 mg / L. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.
Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
The process conditions of the fuel gas are as follows: Temperature = 25 deg C Pressure = 4 bar g Calculate the line size for the fuel gas supply line to the superheater
Explain some of the consequences of an undersized kettle type reboiler?
X is strong but has a very low density (1% of traditional earth materials.) and hence light weight. It is a recyclable material. The compression behaviour of X is strain rate dependent. Higher strain rates result in higher initial modulus and higher compression strength. It can also withstand unlimited number of cycling loading provided the repetitive loads are kept below 80% of the compressive strength. The internal structure of the material includes air-traps which make it poor heat conductor. X is non- biodegradable and chemically inert in both soil and water. Most acids and their water solutions do not attack it; however strong oxidizing acids do. Solvents which attack X include esters, ketones, ethers, aromatic and aliphatic hydrocarbons and their emulsions, among others. It does not support bacterial/fungal growth as well .It also has significant acoustic properties and effectively reduces the transmission of airborne sound. X is combustible and should not be exposed to open flame or other ignition sources. Combustion products are carbon monoxide, carbon dioxide, water and soot. Long-term exposure to sunlight causes yellowing and a slight embrittlement of the surface due to ultraviolet light. X is able to withstand the rigours of temperature cycling, assuring long-term performance.
What are the factors involved in considering the choice of dry screw compressor?
What do you understand by wet bulb globe temperature?
What is fuel requirement of 20kg/hr of incineration having material calorific value 6500 kcal/kg and diesel calorific value 10707 Kcal/Kg (PCC=850 degC and SCC 1050 Deg c)
Name some common causes of control valve noise?
Name the three classes of organic solvents?
Explain how can you estimate a gas flow based on two pressure measurements?
i am going to appear vedanta written test so plz can any body suggest me for this on madhu.5393@gmail.com
Explain how can you estimate the efficiency of a pump?
Which type of pneumatic control valve is used mostly Either Air to Open r Air to close the value And guys I need reason for your reason
what is load and what are the types of load?
how we can find solubility of liquid in amyl alcohol and relative solubility of amyl alcohol
What is a black body?