What is the unit of F M ratio?
The term Food to Microorganism Ratio (F/M) is actually a measurement of the amount of incoming food ( Lbs of Influent CBOD) divided by the Lbs of Microorganisms in your system.
What is a low F M ratio?
Having a low F:M ratio, means you have too many bacteria in your wastewater system relative to the incoming Biochemical Oxygen Demand (BOD). This causes starvation of healthy floc forming bacteria, and issues such as bulking, or high effluent Total Suspended Solids (TSS).
What is the typical value of the F M ratio considered for an ASP process?
0.04 g/g.d.
Explanation: The typical F/M value considered for an ASP process is 0.04 g/g.d. This is a process parameter that is used to characterize the operating conditions.
How do you increase FM ratio?
[a]Adding an external source of organic carbon can help increase the F:M in a wastewater treatment facility. Organic carbon is an essential requirement to grow a strong treatment biomass. Increasing organic carbon loads in a wastewater plant boosts the “F” side of the ratio. This results in a higher F:M value.
What is good FM ratio?
The optimal range for the F:M ratio in a complete mix system is 0.2 to 0.6 lb BOD/lb MLVSS (kg BOD/kg MLVSS).
How does FM relate to sludge age?
F/M is defined as the amount of BOD entering the system to mass of biomas in the aeration tank. Sludge age represents the time for which biomass remain in the system. It is defined as the ratio of mass of biomass in the aeration tank to the mass of biomass leaving the system per day.
What is COD formula?
There is a formula for calculating COD. Consider the formula for COD calculation: (a – b) X C X 8,000 / the volume of the sample in mL. Let “a” represent the titrant used for your sample expressed in mL.
How is COD load calculated?
BOD (or COD) load: Units: kg/day 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 I lower my FM ratio?
[b] Increasing the aeration in a treatment process can help decrease F:M. Turning up aeration adds dissolved oxygen to the treatment system. Most microorganisms that break down organic material for growth and function require oxygen to facilitate the process.
How is COD BOD ratio calculated?
To establish the COD:BOD ratio for your wastewater, simply have both COD and BOD run on several wastewater samples. Divide the COD concentration by the BOD concentration for each sample and average the results.
How is BOD and COD measured?
COD is the most popular alternative test to BOD for establishing the concentration of organic matter in wastewater samples….Can I use my COD results to predict my BOD?
| Sample 1: | COD = 2,150 mg/L | BOD = 1,100 mg/L |
|---|---|---|
| Sample 3: | COD = 1,850 mg/L | BOD = 997 mg/L |
| COD ÷ BOD = 1,850 ÷ 997 = 1.86 |
What is BOD and COD?
The biochemical oxygen demand (BOD) represents the amount of dissolved oxygen (DO) consumed by biological organisms when they decompose organic matter in water. The chemical oxygen demand (COD) is the amount of oxygen consumed when the water sample is chemically oxidised.
How is COD measured?
COD is measured via a laboratory assay in which a sample is incubated with a strong chemical oxidant for a specified time interval and at constant temperature (usually 2 h at 150°C). The most commonly used oxidant is potassium dichromate, which is used in combination with boiling sulphuric acid.