# How do you calculate BOD COD ratio?

## How do you calculate BOD COD ratio?

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.

What is the ratio of BOD to COD?

The corresponding BOD/TOC ratio for untreated wastewater varies from 1.2 to 2.0….

Type of wastewater BOD/COD BOD/TOC
After primary settling 0.4 – 0.6 0.8 – 1.2
Final effluent 0.1 – 0.3 0.2 – 0.5

What is COD formula?

Chemical oxygen demand, or COD, is a test that measures the amount of organic compounds in water. 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.

### What is the formula for the BOD test?

1N sulfuric acid or sodium hydroxide required = (2.1 ml x 1000 ml)/50 ml = 2100/50 = 42 ml. Note: Hydrochloric acid or other acid containing chlorine should not be used to neutralize the sample because chlorine interferes the results of wastewater BOD.

Why is COD higher than BOD?

COD stands for ‘Chemical Oxygen Demand’ where BOD stands for Biochemical Oxygen Demand. COD is normally higher than BOD because more organic compounds can be chemically oxidised than biologically oxidised.

What is BOD COD and do?

BOD is the amount of oxygen that will be consumed by bacteria or other aerobic microorganisms while decomposing organic matter under aerobic conditions. COD measures the amount of oxygen that will be consumed by the chemical breakdown, or oxidation (degeneration) of organic pollutants in water.

#### Can you convert COD to BOD?

Typically, the average BOD result is divided by the average COD result to find a “conversion factor” between the two parameters. One would then multiply their COD results by this factor to estimate BOD. Total Organic Carbon (TOC) measurements can also be used to estimate BOD using a correlation.

How COD is measured?

12.2. COD is an indicative measure of the amount of oxygen that can be consumed by reactions in a measured solution. It is commonly expressed in mass of oxygen consumed over volume of solution, which in SI units is milligrams per liter (mg/L).

What is COD and BOD?

COD or Chemical Oxygen Demand is the total measurement of all chemicals (organics & in-organics) in the water / waste water; BOD is a measure of, the amount of oxygen that require for the bacteria to degrade the organic components present in water / waste water.

## What is a good BOD level?

A BOD level of 1-2 ppm is considered very good. There will not be much organic waste present in the water supply. A water supply with a BOD level of 3-5 ppm is considered moderately clean.

What is a good COD level?

Influent COD in normal domestic sewage is therefore generally 600 – 900 mg/l and it is then treated to at least 75 -100 mg/l before discharge to minimise pollution potential.

Is high COD good or bad?

1.1 Chemical Oxygen Demand. COD is an indicative measurement of the amount of oxygen that can be consumed by reactions in a measured solution. COD detection can be used to easily quantify the amount of organics in water. The higher the COD value, the more serious the pollution of organic matter by water.

### How to calculate Cod BOD ratio for wastewater?

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. For example, below is the COD:BOD ratio developed using three wastewater samples from a food processor:

Is there any relationship between cod and BOD?

For example, food processing wastewater will generally have a COD:BOD ratio of ~2:1, while textile wastewater that can contain dyes will often have a much higher COD:BOD ratio of ~5:1. To establish the COD:BOD ratio for your wastewater, simply have both COD and BOD run on several wastewater samples.

What is the ratio of bod to thod?

This ratio can also vary widely depending on the state of biodegradation of the wastewater. The author has found this ratio as low as 0.1 after several days of oxidation. If the BOD of a biodegradable wastewater equals zero, the wastewater will be completely biodegraded.

#### How are BOD5, Cod, and TOC tests related?

Because BOD5 and COD tests directly measure the amount of oxygen required to stabilize a waste sample, results reflect the original oxidation state of the chemical pollutants. The relationship between BOD5, COD, and TOC is shown below. COD test results can also be used to estimate the BOD5 results for a given sample.