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Chemical Oxygen Demand

cod bod assay measured

Chemical oxygen demand (COD) is a measure of the capacity of water to consume oxygen during the decomposition of organic matter and the oxidation of inorganic chemicals such as ammonia and nitrite. COD measurements are commonly made on samples of waste waters or of natural waters contaminated by domestic or industrial wastes. Chemical oxygen demand is measured as a standardized laboratory assay in which a closed water sample is incubated with a strong chemical oxidant under specific conditions of temperature and for a particular period of time. A commonly used oxidant in COD assays is potassium dichromate (K2Cr2O7) which is used in combination with boiling sulfuric acid (H2SO4). Because this chemical oxidant is not specific to oxygen-consuming chemicals that are organic or inorganic, both of these sources of oxygen demand are measured in a COD assay.

Chemical oxygen demand is related to biochemical oxygen demand (BOD), another standard test for assaying the oxygen-demanding strength of waste waters. However, biochemicaloxygen demand only measures the amount of oxygen consumed by microbial oxidation and is most relevant to waters rich in organic matter. It is important to understand that COD and BOD do not necessarily measure the same types of oxygen consumption. For example, COD does not measure the oxygen-consuming potential associated with certain dissolved organic compounds such as acetate. However, acetate can be metabolized by microorganisms and would therefore be detected in an assay of BOD. In contrast, the oxygen-consuming potential of cellulose is not measured during a short-term BOD assay, but it is measured during a COD test.

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over 4 years ago

1.I working for pickles food company, we are having a problem with our COD and BOD, please help ,how can we solve it, but our effuent results, in term of pH and Tss are good.please help me urgently.

2.I want to know that how calculate COD and BOD? pls help me.

3.How can you differentiate between the COD and BOD?

4.Give the information how to calculate %oxygen consume.i mean formulas



5.Raw effluent of Pharma company the cod, bod is high how to reduce the cod & bod. & how to design the aeration tank capacity.

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about 3 years ago

I want to know about the difference between COD & BOD.

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over 4 years ago

can u tell me why we use sulphuric acid for COD determination?

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about 4 years ago

I run a number of Extended Aeration and Sequential Batch Reactor portable Waste water treatment plants, what steps can I take to ensure that the COD and BOD in the final effluent produced have minimal impact on the receiving environment. An example of two succesive samples are as follows 1st ph 7.2, tss 21, BOD 97, COD 340,

2nd ph 6.8, tss 53, BOD <4, COD 500,these are of from the same unit two weeks apart! Any insight is sincerely appreciated

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over 5 years ago

Hi,
Thanks for such an excellent publication. After reading it, i realized that my doubts about the difference between COD and BOD were cleared.However, please include some quantitative analysis and laboratory procedures.

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over 5 years ago

Good day sir...

Sir,i want to know how to reduce or decrease COD and BOD levels at industrial waste water or effluent...? In my company COD and BOD levels are very high, up to 1000 ppm. Please help me..

I'm waiting for your answer.! Thank's...

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over 5 years ago

Dear sir,

Please tell me How to calculate COD and BOD and Procedure.

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over 5 years ago

Hello sir

I want to know that how calculate COD and BOD? pls help me.

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almost 4 years ago

After chlorination COD will increase or decrease?Because chlorine is also one of the oxidizing agent. it may interfear with the interference of pottassium dichromate as an oxidizing agent?

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almost 4 years ago

what factors correlate cod and bod

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over 3 years ago

may i know how to deacreas the COD of the water.without effecting conductivity of water.

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almost 3 years ago

plz inform method to minimize COD, its about 15,000mg/l.

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over 3 years ago

Please tell me ways I can reduce COD/BOD levels in industrial waste water.

Read more: Chemical Oxygen Demand - Cod, Bod, Assay, Measured, Waters, and Organic http://science.jrank.org/pages/1388/Chemical-Oxygen-Demand.html#ixzz1E9C9kJ00

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over 2 years ago

what is the relation between COD & PH ?

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about 6 years ago

Rescepted sir,

Please sir tell me can we increase the COD of perticular organic material and how?

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about 2 years ago

please tell me how to calculate c.o.d,b.o.d by titration in a laboratory.chemicals used with procedure and formula to calcolate.

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over 3 years ago

tq. for the explanation. now i got some view.

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almost 4 years ago

how can you control cod in galvanizing line effluent

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over 4 years ago

what is the samling protocl in getting the COD???

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over 5 years ago

Dear Sir,
Good day could you help me on what are the procedure on how to calculate hte COD and the reagents to be used.We have a product an acidic liquid soap and a basic liquid soap which we must test the COD.Thank you! God bless!

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almost 5 years ago

Sir,recently we are doing a project by performing cod test on effluents coming out of some famous industries...could you please help us by cleary giving the details of the chemicals and reagents to carry out this test?

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about 5 years ago

Good day. We have analyzed our BOD and COD content on our effluent. How come our BOD passed the regulatory limit while the COD failed? How can I reduced COD on our effluent?

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over 2 years ago

why we multiply 8000 in calculation COD

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over 3 years ago

very good

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over 2 years ago

Please tell me the calculations of COD ?

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over 4 years ago

how we maintained the cod under control limit if more than >2000 ppm but my ph >7.0.

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almost 5 years ago

Sir,

we use sulphuric acid to neutralize spend caustic but stil we found high COD.

Did you have any way to reduce the COD?

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almost 4 years ago

why cod is higher than bod?mirch masala's company cod can come higher?please reply

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over 6 years ago

Give the information how to calculate %oxygen consume.i mean formulas

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over 3 years ago



How can I reduce the COD of wastewater sample when I'm getting already BOD5 less than 5 ppm.

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over 2 years ago

sorry sir, can you send to me the material of BOD an COD

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over 3 years ago

why cod is higher than bod?please reply


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over 3 years ago

may i know any efficent and judicious technique to reduce cod

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over 5 years ago

Dear Sir/Madam, Good day! can you please tell me whether the COD value should increase or decrease when a microbe degrades waste inoculated along with it. please reply me.its urgent..

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almost 6 years ago

I work for a processing industry. Please tell me ways I can reduce COD/BOD levels in industrial waste water.

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almost 3 years ago

Sir I want to know the Parameter of Piclking industry wastewater ie COD,BOD,TSS,PH, kindly provide me this information as soon as possible.

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almost 3 years ago

When applying regression statistics to problems relating the biochemical oxygen demand (BOD) and the chemical oxygen demand (COD), which is the dependent variable and which is the independent variable?

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about 3 years ago

Hi,

My query is will the cod and bod reduce by adjusting the Ph from 12 to 6-8

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about 3 years ago

Thank you

this is agood data

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over 3 years ago

Method analysis for Chemical Oxygen Demand

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about 5 years ago

How can you differentiate between the COD and BOD?

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over 5 years ago

I working for food company, we are having a problem with our COD and BOD, please help ,how can we solve it, but our effuent results, in term of pH and Tss are good.please help me urgently.

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about 6 years ago

Plz tell me in a lake eco-system for poluuting the lake how COD contributes?

I also want to know is there any relation ship between BOD and COD?

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about 6 years ago

Iwant to know that, is the process said above (cod test process)recognised by APHA?

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about 6 years ago

Dear Sir, Plz tell me how to reduce the cod in paint effluent what vare the treatments and methods

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almost 5 years ago

Is there any other method to calculate the COD without using the formula.

8000(b-a)n/vol. sample

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about 2 years ago

can you give give me advantages and disadvantages of b.o.d and c.o.d. test

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over 2 years ago

 Why do COD and BOD analysis usually give different results for same waste?
 What is the intrinsic limitation of the test lies in its inability to differentiate between the biologically oxidization and biologically insert material.

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almost 3 years ago

Sir,

Pl elobrate on the areas where to opt for BOD Or COD test.Further,kindly share a tabulated comparison of COD and BOD covering the aspects of technicalities,conditionalities and the economy.

Regards

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over 3 years ago

i need units for cod,bod,tds, tts,alkalinity,acidity,etc.,

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over 3 years ago

Pl provide all answars of below questions

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over 3 years ago

i need poroje about cod

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almost 4 years ago

what is the function of adding mercury sulphate in the water samples?

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over 4 years ago

when i found to this website im quite interest to write some idea to nilu..what do means to prepare reagent. is it reagent for cod testing ?

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about 5 years ago

Respected Sir can you tell how oxygen can be detected in laboratory by simple chemical test in organic compounds.

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over 5 years ago

i want to know the effect of the Biological Oxygen Demand, Chemical Oxygen Demand and the Disolved Oxygen when it has high concentration.

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almost 6 years ago

thanks in advance. whats the relationship between COD and BOD- Is it possible to use biological means to reduce cod.

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almost 6 years ago

Hello sir, I want to measure H acid degradation by white rot fungi. I want to know is it possible to measure its degradation by COD? Can I determine its degradation using COD?

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almost 6 years ago

Good Day, I would like to know why do we add minerals in dilution water like MnSo4, FeCl3. What are the effects of this compound to the dilution water? What is the purpose of Glutamic acid or GGA that we used in our standard? And most important the purpose of SEED in the analysis. I was just curious in the addition of dilution water that we used to fill up the BOD bottle to 300 ml. Thanks...

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over 6 years ago

plz tell me the standard procedure 2 calculate the cod that means i want 2 know the materials required, reagents
requered,procedure, observation table, formula, precaution etc related with during cod measurement during lab

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about 1 month ago

I want to know about the difference between COD & BOD.

Read more: Chemical Oxygen Demand - Cod, Bod, Assay, and Measured - JRank Articles http://science.jrank.org/pages/1388/Chemical-Oxygen-Demand.html#ixzz33Hd2myHV

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11 months ago

Please tell me How to calculate COD and BOD and Procedure.

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over 1 year ago

can i know why blank titration and back titration are done ??? and why back titration first and then blank titration

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over 1 year ago

why we multiply 8000 in calculation COD

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almost 2 years ago

I want to know that specific importance of COD and BOD.

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almost 2 years ago

How to resuce the C.O.D. of effluent waste water which contains amines(E.D.A) about 7 to 10%.present the C.O,D is about 35000 ppm want to reduce to 2000ppm.

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about 2 years ago



I want to know about the difference between COD & BOD.







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over 2 years ago

i would like to know how many mg/l of COD and BOD used in Lao PDR?

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over 2 years ago

How to calculate BOD & COD valve by aeration system?

How to find SOTE for Fine pore diffuser theoritically?

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over 2 years ago

Initially i was comfused between cod and bod,now i can differeciate. THANKS



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over 2 years ago

we are testing cod for underground water, want to know why sometimes blank readings are smaller than samples

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over 2 years ago

dear sir can we measure O2 by Using IR source. Plz tell me about this briefly, if we can measure, why & why not?

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over 2 years ago

sir i want to ask you that how to measure COD by wet method.plz tell me.

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over 2 years ago

please,tell about marpol standard for COD in waste water treatment unit

outlet.

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over 2 years ago

plzzzzzzzzzzzzzzzzzz
sir tell me about,
reduction of cod in underground water using photocatalytic oxidation.

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over 2 years ago

How can determine bod and cod? please help me.

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over 2 years ago

please tell me if cod value decrease or increase in Aeration tank . i.e. from influent to effluent

thanks

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over 2 years ago

Meaning of LT 2 in BOD terms?

Meaning of LT 2 in oil & grease terms in waste water?

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almost 3 years ago

Sir,

Pl elobrate on the areas where to opt for BOD Or COD test.Further,kindly share a tabulated comparison of COD and BOD covering the aspects of technicalities,conditionalities and the economy.

Regards

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almost 3 years ago

why cod>bod

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about 3 years ago

plz send me COD & BOD procedure.

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about 3 years ago

please give detail of mathmathecal calculation of cod bod & toc of any organic compounds

Thanks

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about 3 years ago

Hi!i work for APSARA Authority in Siem Reap,Cambodia,in Department of Water Management.I have many questions and need your helps.

1.please summarize about the adavntage and disadvantage of BOD and COD in the water when it's capacity high and low.

2.I'd like to know how to calculate BOD and COD?

3.How can you differentiate between the BOD and COD?please help me.

Many thanks

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over 3 years ago

sir,may u help to me tell about cod determination method for a soft drink industry.....

i hopo i get responce as soon as posible.

thankyou..

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over 3 years ago

wht are the effects of COD nd BOD to Environment

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over 3 years ago

Dear;

how can form the COD and BOD to solve the problem of cod&bod leval please replay

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almost 4 years ago

what factors affect COD apart from oil and grease

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about 4 years ago

1.0 COD ONLY MEASURS THE ORGANIC CPDS DISSOLVD IN WATER Am i correct?

2.0If we know the structure of the organic cpd please tell me the calculation method of COD clearly with a example.

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about 4 years ago

sir
why we used potassium dichromate and have another formula to perform COD test. THANK YOU

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over 4 years ago

what method should be taken to solve if potassium dichromate is not in excess during determination?

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over 4 years ago

how does seasonal variations alter COD concengtrations

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over 4 years ago

What are the factors that affect high COD concentration? Can sample pH affects it?

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over 4 years ago

dear sir,

how is it possible that the COD reading fluctuated from 20 mg/L to 71 mg/L in river water which has low BOD,TSS,TDS,TCC and TFC?pls give me possible sources as soon as possible..thanx..

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over 4 years ago

sir,we are doing research on effluents containing dyes,could plz tell me the exact procedure and how to prepare reagent..and what is COD acid ?

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over 4 years ago

Are There any Expriment ran on Lab-on-Chip

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over 4 years ago

why one has to perform a COD or BOD or DO test

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almost 5 years ago

may i know what is the reason that cause the measured COD reading is overange or underange? tahnks>

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about 5 years ago

dear sir, can you give some information , if cooling tower water contains COD 296 mg/lt and BOD 90 mg/lt. is there any corrosion problem [small pinholes in return water lines].what is the reason kindly mail me .gsn@indochem.in