Table of Contents
- 1 How BOD can be removed using activated sludge system?
- 2 How can we reduce BOD and COD in industrial wastewater?
- 3 What is the permissible limit of BOD in wastewater?
- 4 What is activated sludge treatment and how does it does it reduce BOD in wastewater?
- 5 What is BOD in sewage treatment plant?
- 6 Does chlorine increase BOD?
- 7 How to reduce BOD level at the entrance of an aeration tank?
- 8 What are the applications of biological oxygen demand in wastewater treatment?
How BOD can be removed using activated sludge system?
The biomass uses the BOD5 in wastewater as their food source. The AS process converts the organic waste materials to simpler compounds such as carbon dioxide, nitrates, sulfates, and more biomass. These substrates are removed from the water by either settling, DAF, or membrane separation.
How can BOD of sewage water be reduced?
BOD is fairly easy to remove from sewage by providing a supply of oxygen during the treatment process; the oxygen supports bacterial growth which breaks down the organic BOD. Most enhanced treatment units described incorporate some type of unit which actively oxygenates the sewage to reduce BOD.
How can we reduce BOD and COD in industrial wastewater?
You can reduce COD and BOD by adding hydrogen peroxide to the wastewater solution. The hydrogen peroxide will chemically attack the organics in the wastewater, degrading them and reducing the measured COD and BOD.
Does chlorine reduce bod?
BOD reduction: Chlorine accomplishes BOD reduction by oxidation of organic compounds present in wastewaters. Oxidation of metal ions: Metal ions which are in reduced state are oxidized by chlorine (e.g., ferrous to ferric ion and manganous to manganic ions).
What is the permissible limit of BOD in wastewater?
| Parameter | Unit | Maximum permissible limit |
|---|---|---|
| Chemical Oxygen Demand (COD) | mg/l | 120 |
| Biochemical Oxygen Demand (BOD5) | mg/l | 40 |
| Chloride | mg/l | 750 |
| Sulphate | mg/l | 750 |
How do you reduce BOD and COD?
Hydrogen peroxide (H2O2) has been used to reduce the BOD and COD of industrial wastewaters for many years.
What is activated sludge treatment and how does it does it reduce BOD in wastewater?
In the activated sludge process, reactants, food, and microorganisms are mixed in a controlled environment to optimize BOD removal. The process incorporates the return of concentrated microorganisms to the influent waste.
Does chlorine reduce BOD?
BOD reduction: Chlorine accomplishes BOD reduction by oxidation of organic compounds present in wastewaters. 4. Oxidation of metal ions: Metal ions which are in reduced state are oxidized by chlorine (e.g., ferrous to ferric ion and manganous to manganic ions).
What is BOD in sewage treatment plant?
Biochemical oxygen demand (BOD) represents the amount of oxygen consumed by bacteria and other microorganisms while they decompose organic matter under aerobic (oxygen is present) conditions at a specified temperature.
What is BOD limit?
For drinking water BOD has to be less than 5 mg/L and for treated wastewater to be disposed of in the water bodies it is 30 mg/L, 100 mg/L if treated waste water is discharged into the sewerage system in India.
Does chlorine increase BOD?
Chlorine dosages above 10 mg l−1 resulted in increased BOD and COD levels of the effluent, with chlorine dosages above 30 mg l−1 resulted in almost double the original BOD and COD values. Effects of chlorine on BOD and COD were also confirmed by actual data reported by the treatment plant.
How does BOD affect wastewater treatment plants?
To remove BOD, a wastewater treatment plant has to aerate the water, which requires a lot of horsepower, aka electricity. Greater BOD also ends up with greater amounts of sludge to dispose of. High concentrations of TSS can cause clogs and scour pipes and even machinery.
How to reduce BOD level at the entrance of an aeration tank?
The BOD level at the entrance of an aeration tank depends on 3 things. So, In order to reduce BOD before aeration… One has to install efficient primary and preliminary treatment units where most of the bigger organic matter (like floating solids, suspended solids etc) can be removed. For this —
What are the three common BOD reduction methods for wastewater treatment?
Three common BOD reduction methods for wastewater treatment are: 1 Wastewater clarification 2 Wastewater separation (Coagulation & Flocculation) 3 Anaerobic microbial decomposition More
What are the applications of biological oxygen demand in wastewater treatment?
Applications of Biological Oxygen Demand in Wastewater Treatment. Wastewater treatment plants use BOD value as an index to ascertain the overall degree of organic pollution in a water source. A BOD test is typically carried out over a standard 5-day incubation period at 20°C (68°F) for the most accurate results.