Dear Lalinda,

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.

Hydrogen peroxide (H2O2) has been used to reduce the BOD and COD of industrial wastewaters for many years. While the cost of removing BOD and COD through chemical oxidation with hydrogen peroxide is typically greater than that through physical or biological means, there are nonetheless specific situations which justify the use of hydrogen peroxide. These include: Predigestion of wastewaters which contain moderate to high levels of compounds that are toxic, inhibitory, or recalcitrant to biological treatment (e.g., pesticides, plasticizers, resins, coolants, and dyestuffs);

- Pretreatment of high strength / low flow wastewaters – where biotreatment may not be practical – prior to discharge to a Publicly Owned Treatment Works (POTW);

- Enhanced separation of entrained organics by flotation and settling processes; and

- Supply of supplemental Dissolved Oxygen (DO) when biological treatment systems experience temporary overloads or equipment failure.

As indicated by these examples, H2O2 can be used as a stand-alone treatment or as an enhancement to existing physical or biological treatment processes, depending on the situation.

With my best regards

Prof. Bachir ACHOUR

Hi Lalinda,

I would just add to the previous response the following potential technologies:

1) Addition of ozone

2) Advanced oxidation (UV/Ozone; UV/H2O2/O3; electrochemical advanced oxidation) -- the formation of hydroxyl (and other) radicals

3) sand filters/biofilters

4) chemicals that promote flocculation (followed by settling or filtering)

There are lots of options out there, I hope you find the one that works best for your application.

Best regards,

Thomas

You can also use coagulants and dissolved air flotation (DAF) techniques. Cost and selected treatment technology always depends on the nature of the wastewater and the desired level of treatment.  

Ozone is  economically viable  for Final step of waste water treatment before releasing it back into the environment or reuse ,otherwise economically viability depends on selection of technology and selection of technology depends on effluent conditions . 

Water treatment with ozone is an effective method to reduce BOD and COD levels in industrial and municipal waste water. BOD and COD control with ozone can be used in water treatment systems for:

Water recycling allowing cost and energy savings to be made on the overall water usage as well as water treatment cost.

an already existing water treatment system in order to reduce BOD and COD levels further

The use of ozone is a very cost efficient and environmentally friendly option for BOD and COD control and reduction.

Take care with O3.  In the troiposphere is toxic and acarcinogen.

YOU can also use Resin ion exchange, the resin can easily be reused after treatment

Well,

AERATION PROCESS.

Sincerely

AOP and Coagulation.

synergistic effect of Plasma/Hydrodynamic cavitation works well

Ahmad Najafidoust

Both COD and BOD are removed by following secondary treatment of waste water. These are Trickling filter, Rotating biological Disc, Oxidation pond and by Activated sludge processes.

Dear Lalinda,

To reduce COD/BOD content present in the wastewater you can use methods like

For more information, you may refer Chapter Wastewater Treatment: An Overview

Dear Dr Lalinda Geekiyanage

The activated sludge processes is an efficient and economic ways for treatment of organic wastewater to remove not only BOD, but also nitrogen and phosphorus.

Best regards

Fatah BOUTELDJAOUI

Hello Dear Lalinda Geekiyanage

Advanced Oxidation Process is an efficient ways for the removal of COD

Best is K2FeO4. produced by electrolysis

you can remove it by using DAF also.

Advanced oxidation process, coagulation, flocculation, adsorption, etc. are used to reduce BOD and COD

hi

i have a waste water and the range of its cod is 482 but it cant reduce

ph=2.3

no3=180

cr=15 ppm

i use fecl3

o3

......

the biological methods like activated sludge and its modifications also Advanced Oxidation Process can use to do that

sequential biological anaerobic - aerobic treatment of wastewater

i am using biological methods such probiotics and feed management