If the wastewater has been adequately treated the level of biological contaminants in the sample will be low enough that the BOD 5 will be < 0.2 mg/L of liquid. The general equation for the determination of a BOD5 value is: BOD5 (mg/L) = D1 - D2 / P D 1 = initial DO (dissolved oxygen level) of the sample,
Full Answer
What is the BOD5 value of wastewater?
If the wastewater has been adequately treated the level of biological contaminants in the sample will be low enough that the BOD 5 will be < 0.2 mg/L of liquid. The general equation for the determination of a BOD5 value is: BOD5 (mg/L) = D1 - D2 / P D 1 = initial DO (dissolved oxygen level) of the sample,
How do you calculate BOD5 value?
The general equation for the determination of a BOD5 value is: BOD5 (mg/L) = D1 - D2 / P D 1 = initial DO (dissolved oxygen level) of the sample, D 2 = final DO of the sample at the end of the 5 day incubation period
What percentage of incoming BOD is being removed by wastewater treatment?
When we multiply that by 100 we see that this wastewater treatment plant is removing 91% of the incoming BOD. And that my friend is how this problem is solved.
How do you calculate efficiency of wastewater treatment plant?
Efficiency = [ (IN – Out)/IN] x 100. Plugging in our numbers and doing the math we see that we take our 245 mg per liter and subtract from that the 22. Then we divide by 245 which is what’s coming in. When we multiply that by 100 we see that this wastewater treatment plant is removing 91% of the incoming BOD.
How do you calculate the capacity of a sewage treatment plant?
Multiply your Minimum Population (P) by 150 to get your daily estimated wastewater production. For example, a three bed house with a Minimum Population (P) of 5 people would have a daily estimated wastewater production of 750 litres per day (5 x 150).
How is BOD reduction calculated?
We have a formula that says efficiency or removal efficiency equals what's coming in minus what's coming out then you divide that by what's coming in and then we multiply by a 100 to convert the decimal to a percent.
How do I calculate BOD load?
BOD (or COD) load: Units: kg/day The concentration of BOD (in mg/l) in the influent can be used to calculate the total BOD load per day being treated. This is simply done by multiplying the BOD in mg/l by the daily effluent volume in cubic metres (m3) and dividing the product by 1000.
How do you calculate gallons per day for a sewer?
Daily Sewage Flow. Multiply the ultimate population by per capita average daily sewage flow to obtain the average daily sewage flow e.g.
How is effluent bod5 calculated?
3:075:39Problem Solved: BOD Problem - Wastewater Math - YouTubeYouTubeStart of suggested clipEnd of suggested clipWe use the formula that says our initial dissolved oxygen - the final dissolved oxygen times 300MoreWe use the formula that says our initial dissolved oxygen - the final dissolved oxygen times 300 milliliters which is the size of the sample bottle divided by the milliliters of sample.
How many percentage of BOD removes in primary treatment?
Primary treatment removes about 60 percent of total suspended solids and about 35 percent of BOD; dissolved impurities are not removed. It is usually used as a first step before secondary treatment.
What is the formula for BOD?
Calculate the volume of 1N sulfuric acid or sodium hydroxide to be added to neutralize the 1000 ml sample as follows: 1N sulfuric acid or sodium hydroxide required = (2.1 ml x 1000 ml)/50 ml = 2100/50 = 42 ml.
What is BOD loading rate?
Organic loading rate is defined as the application of soluble and particulate organic matter. It is typically expressed on an area basis as pounds of BOD5 per unit area per unit time, such as pounds of BOD5 per square foot per day (lb/ft2/day).
How do you calculate daily flow rate?
If you can see the fluid flowing, you can measure its velocity, and that means all you need is the area through which the fluid is flowing to calculate the flow rate using the formula Q = A × v.
How do you calculate wastewater?
Right Cylinder = (0.785) x (D2,ft) x (Height or Depth,ft) Volume, cu. ft. i) Vol, Gals = Multiply the above by the factor 7.48 gals/cu. ft.
How do you calculate flow rate in GPM?
The formula to find GPM is 60 divided by the seconds it takes to fill a one-gallon container (60 / seconds = GPM). Example: The one-gallon container fills in 5 seconds, breakdown: 60 divided by 5 equals 12 gallons per minute.
Most recent answer
For this you may also require dilution water, ie. diluting the sample with a mixture of aerated dilution water to 25%, and then finding the initial DO and incubating it for 5 days and finding the final DO, as mentioned by other experts. this dilution is required as the waste water will have nil initial DO when we directly measure the DO.
All Answers (7)
BOD5 is depend not only on amounts of pollutants but characteristics of the pollutants. If pollutants are easily degradable oxygen consumption is high during initial stage, but refrectory matters will not biodegraded within short term and BOD5 could be estimated low. Hence, basically not possible to calculate only with provided information.
Similar questions and discussions
What is sustainability? How can we make sustainable development a reality? How sustainability can be measured?
What is BOD5 in water treatment?
A standard parameter in the treatment of both waste and surface waters, BOD5 corresponds more specifically to the quantity of oxygen consumed by micro-organisms over a period of five days. It is widely employed to measure a water treatment plant’s capacity.
What is the BOD5 measure?
The BOD5 measure is very widely used, in particular to check the regulatory conformity of effluent from urban and industrial wastewater treatment plants.
Is it necessary to dilute a sample before measuring Bod5?
It is sometimes necessary to dilute the sample before measuring BOD5. In cases where BOD is particularly high, all the dissolved O 2 may in fact be consumed before the 5-day period has ended. The capacity of a water treatment plant is measured in PE (Population Equivalents), based on BOD5.
Is BOD5 higher than COD?
But just to recap, BOD5 measures only the consumption of oxygen by micro-organisms, i.e. biodegradable pollution. COD, which measures both biodegradable and non-biodegradable pollution, is thus higher than BOD5. The COD/BOD5 relationship allows the biodegradability of an effluent to be assessed: < 2: effluent readily biodegradable.
What does the BOD5 value mean?
The BOD5 value has been used and reported for many applications, most commonly to indicate the effects of sewage and other organic wastes on dissolved oxygen in surface waters (see TECHNICAL NOTE). The 5-day value, however, represents only a portion of the total biochemical oxygen demand.
What is the purpose of the BOD 5 test?
The standard 5-day BOD 5 test for biological oxygen demand in wastewater is used to evaluate the effectiveness of wastewater treatment by a public or private sewer or septic system. If a system is not adequately treating its wastewater to remove biological pollutants the implication is that biological contaminants - a health hazard - are being discharged into the environment and thus potentially into local waterways and into drinking water supplies.
How long does it take for a BOD to be performed?
Ideally the wastewater sample is delivered immediately to the test lab and the BOD test is performed immediately. If the sample cannot be delivered to the test laboratory within two hours it must be refrigerated and delivered to the test laboratory within 24-hours.
What are the stages of decomposition?
Two Stages of Decomposition of Biological Materials in Wastewater 1 The carbonaceous stage, or first stage, represents that portion of oxygen demand involved in the conversion of organic carbon to carbon dioxide. 2 The nitrogenous stage, or second stage, represents a combined carbonaceous plus nitrogeneous demand, when organic nitrogen, ammonia, and nitrite are converted to nitrate. Nitrogenous oxygen demand generally begins after about 6 days.#N#For some sewage, especially discharge from wastewater treatment plants utilizing biological treatment processes, nitrification can occur in less than 5 days if ammonia, nitrite, and nitrifying bacteria are present. In this case, a chemical compound that prevents nitrification should be added to the sample if the intent is to measure only the carbonaceous demand.#N#The results are reported as carbonaceous BOD (CBOD), or as CBOD5 when a nitrification inhibitor is used.
How long does it take for a sewage discharge to nitrate?
For some sewage, especially discharge from wastewater treatment plants utilizing biological treatment processes, nitrification can occur in less than 5 days if ammonia, nitrite, and nitrifying bacteria are present.
What is COD in water?
COD is defined as "total measurement of all chemicals in the water that can be oxidized" or as the amount of oxygen required to oxidize organic matter chemically.
Can TOC be used to estimate BOD?
For a given wastewater, if a repeatable empirical relationship is established between its TOC and BOD or COD, then measurements in TOC can be used to estimate the accompanying BOD or COD.
What is BOD5 in wastewater?
Typically, municipal wastewater treatment plants will use BOD5 as a measure of the organic concentration into, and through, the wastewater plant. Industrial wastewater systems will more often use COD to measure the organic concentration moving through the treatment plant. In my experience, I see TOC being used much less often (rarely) ...
What is the BOD5 test?
The BOD5 test measures the oxygen consumed by microorganisms as they oxidize (consume or eat) the soluble organic matter in the wastewater. But the BOD5 test is a somewhat unreliable means of determining the amount of organic matter present in water. The test measures only the approximate amount of oxygen that will be required ...
How long does it take to complete the Bod5 test?
Due to the length of time required to complete the BOD5 test (five days), BOD results provide historical data only and do not facilitate rapid water quality assessment for optimal process control. The often highly variable chemical composition ...
How long does it take to test for organics in wastewater?
The often highly variable chemical composition and strength of industrial wastewater requires a much more rapid method for measuring the organic concentration, hence the use of the two hour COD test or, in some plants, the 30 minute TOC analysis.
What is the purpose of a wastewater test?
The test measures only the approximate amount of oxygen that will be required (absorbed or consumed) by a wastewater when it is exposed to air or oxygen for an extended period of time. Toxic substances in the wastewater inhibit or even prevent bacterial growth and, therefore, oxidation of the organic matter.