Bod dan cod sebagai parameter pencemaran air dan baku mutu air limbah oleh. Cod reduction, wastewater treatment beckart environmental. Oct 30, 2018 biochemical oxygen demand or biological oxygen demand bod is a measure of the amount of dissolved oxygen do required by aerobic microorganisms to decompose organic matter present in a sample of water at a certain temperature over a studied period. It is used in water quality management and assessment, ecology and environmental science. Biochemical oxygen demand bod is a chemical procedure for determining how fast biological organisms use up oxygen in a body of water. Bod analysis is similar in function to chemical oxygen demand cod analysis, in that both measure the amount of organic compounds in water.
The chemical oxygen demand test procedure is based on the chemical. What are the differences between chemical oxygen demand. Summary biochemical oxygen demand bod is a measure of the dissolved oxygen consumed by microorganisms during the oxidation of reduced substances in waters and wastes. Principal wastewater constituents treatment methods for.
Cod is a measure of total organic molecules dissolved in waste water, where as the concept of bod came after cities started dumping their waste water into the water bodies and this led to. The standard method for indirect measurement of the amount of pollution that cannot be oxidized biologically in a sample of water. Biochemical oxygen demand definition is the oxygen used in meeting the metabolic needs of aerobic microorganisms in water rich in organic matter such as water polluted with sewage. The test is also used to examine influents and effluents from. Corrosionpedia what is a biochemical oxygen demand bod. The more food present in the waste, the more dissolved oxygen do will be required. In comparison, an mfcbased bod sensor of the current output or the ce from the mfc has a linear relationship with the organic carbon strength of the wastewater 1,8 fig. The main difference between bod and cod is that bod is the amount of oxygen which is consumed by bacteria while decomposing organic matter under aerobic conditions whereas cod is the amount of oxygen required for the chemical oxidation of total organic matter in. Many of the researchers chose to define high strength wastewaters as greater than residential strength. The makes them significant when is comes to the treatment of water. Chemical oxygen demand is similar to biochemical oxygen demand in that they are both used to calculate the oxygen demand of a water sample. Terms and definitions of the urban waste water treatment.
Most applications of cod determine the amount of organic pollutants found in surface water e. Generally, industrial wastewater can be divided into two types. Toc or total organic carbon is the measurement of organic carbons. Jun 07, 2017 bod refers to the biochemical oxygen demand and cod is the chemical oxygen demand. But take a look at the bar graph below which shows influent cod bod ratio data for a municipal plant, spanning a two year period, that does have a small industrial contribution. What are the differences between chemical oxygen demand cod and biological oxygen demand bod. For example, the organics in a wastewater sample represented by bod will also be represented in the. Bod, biochemical oxygen demand the bod indicates the content of oxygen needed to decompose organic compounds in waste water by bacteria. A cod test can be used to easily quantify the amount of organics in water. Chemical oxygen demand cod and biological oxygen demand bod are the two main characteristic properties that. Since oxygen is required in the breakdown or decomposition process of wastewater, its demand or bod, is a measure of the concentration of organics in the wastewater. Aug 15, 2019 biochemical oxygen demand bod is a chemical procedure for determining the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period. Biochemical oxygen demand bod is a way to measure organic pollution in water by looking at the rate at which microorganisms in the water use up dissolved oxygen when they metabolize the organic pollutants.
Wastewater treatment and discharge 2006 ipcc guidelines for national greenhouse gas inventories 6. Biological oxygen demand 28 ps2829a the bod 5 test is used to measure the potential of wastewater and other waters to deplete the oxygen level of receiving waters. The main difference between bod and cod is that bod is the amount of oxygen which is consumed by bacteria while decomposing organic matter under aerobic conditions whereas cod is the amount of oxygen required for the chemical oxidation of total organic matter in water. Bod biochemical oxygen demand is supposed to measure the amount of food. In environmental chemistry, the chemical oxygen demand cod is an indicative measure of the amount of oxygen that can be consumed by reactions in a measured solution. However, biochemicaloxygen demand only measures the amount of oxygen consumed by microbial oxidation and is most relevant to waters rich in organic matter. Jun 18, 20 biochemical oxygen demand measures the quantity of oxygen consumed by microorganisms during the decomposition of organic matter. Bod in wastewater is the result of human waste, food waste and other organics which are sent to the sewers.
Biochemical oxygen demand bod and chemical oxygen demand pdf slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Biochemical oxygen demand or bod, is the amount of oxygen needed by organisms to break down the organic material in wastewater. Bod value is usually expressed in milligrams of oxygen per liter of water mgl. Cod is the amount of oxygen required to chemically breakdown the pollutants whereas bod is the amount of oxygen required to do this biologically. The term also refers to a chemical procedure for determining this amount. Wastewater basics 101 target audience policy makers, leaders, and planners people who have a water quality agenda this presentation discusses the fundamentals of converting wastewater back to water how do we humans interact with the hydrologic cycle. Oct 14, 2011 the key difference between bod and cod is that the bod is the oxygen demand of microorganisms to oxidize organic matter in the water under aerobic conditions while the cod is the oxygen demand to oxidize all the pollutants in the water chemically. Dec 30, 2019 as mentioned earlier, bod removal is approximately 50% of the suspended solids removal in primary clarification. Biochemical oxygen demand biological oxygen demand is an important water quality parameter because it provides an index to assess the effect discharged wastewater will have on the receiving environment.
The most commonly used residential strength testing protocol defines residential strength influent as bod 5 100300 mgl, tss 100350 mgl nsf standard no. A full explanation of any of the parameters can be found by clicking on the blue links. Bod cod bod is biodegradable organics during 5 days at 20 degr. These parameters reflect effect and material characteristics of one or more substances. What is the difference in bod, bod5, cbod and nbod, i am so. There are 4 common tests to determine organic pollution in wastewater. Biochemical oxygen demand bod in wastewater treatment. Cod measurements are commonly made on samples of waste watersor.
There are also many different cod tests of which the 4hour cod is probably the most common. Cod is listed in the worlds largest and most authoritative dictionary database of abbreviations and acronyms the free dictionary. The chemical oxygen demand cod test is commonly used to indirectly measure the amount of organic compounds in water. Bod refers to the amount of oxygen consumed by microorganisms to decompose organic matter in water under aerobic conditions. What is the relationship between the cod and bod values in waste. Bod 5 100 3685 mgl, tss 142 4375 mgl, and fog 25 14,958 mgl. The determination of chemical oxygen demand in waters and effluents 2007 methods for the examination of waters and associated materials this booklet contains guidance on methods for the determination of chemical oxygen demand using potassium dichromate solution, and notes for the disposal and recovery of selected reagents. Biochemical oxygen demand bod is the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period.
D biochemical oxygen demand bod is the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given water sample at certain temperature over a specific time period. Cod is closely related to bod or biochemical oxygen demand, the difference being that bod is a test of the level of organic matter that can be biologically oxidised while cod is a test of the amount of organic matter that can be chemically oxidised. What is the relationship between the cod and bod values in waste water. Like the various characteristics of industrial wastewater, the treatment of industrial wastewater must be designed specifically for the particular type of effluent produced. Difference between bod and cod definition, test method and. The qvalue curve for bod used in calculating a water quality index2 illustrates the relationship between bod and water qualitythe higher. Technologybased effluent limitations 53 the regulation also includes an alternate set of standards that apply to certain facilities employing waste stabilization ponds or trickling filters as the principal process. The difference between the two is that chemical oxygen demand measures everything that can be oxidized, whereas biochemical oxygen demand only measures the oxygen demanded by organisms. Chemical oxygen demand cod is a measure of all oxygendemanding substances, including those that are not amenable to biological treatment. Bod test procedure is based on the activities of bacteria and other aerobic microorganisms microbes, which feed on organic matter in presence of oxygen.
Waste is considered to be easily treatable by biological means if bod cod ratio is 0. The bod 5 of a wastewater is determined to be 150 mgl at 20oc. Chemical oxygen demand cod is a second method of estimating how much oxygen would be depleted from a body of receiving water as a result of bacterial action. What is the significance of bod and cod in water quality.
Difference between bod and cod definition, test method and procedure, purpose 19. Biochemical oxygen demand and chemical oxygen demand. Cod is a chemical test, defined as a chemical oxidation of the sample material. The bod test is an estimate of the food available in the sample.
In environmental chemistry, the chemical oxygen demand cod is an indicative measure of. Cash on delivery cod is a type of transaction in which the recipient makes payment for a good at the time of delivery. Biochemical oxygen demand bod biosensors, in general, use the change of the electrical or optical signal to estimate the bod value. Chemical sludge chemicals are used widely in wastewater treatment, especially in industrial wastewater treatment, to precipitate and remove hardtoremove substances, and in some instances, to improve suspended solids removal. Looking for online definition of cod or what cod stands for. Chemical oxygen demand cod vs biological oxygen demand. Both cod and bod test methods aim to give an indication of the amount of pollution in a water sample.
Bod primer page 4 of 61 biological background of all bodn determinations the primary difference between bodn determination and other measurements such as ph, conductivity, oxygen, cod, nitrate, etc. Apr 05, 2020 elizabeth pitt, wife of thomas pitt of haldon, clothier, elizabeth clerke of the same, spinster, and jane topliffe, wife of james topliffe of the same, laborer, for stealing there on 1st nov. Cod reduction is one of the most common challenges faced by any facility that needs to comply with wastewater treatment regulations, and if it isnt properly addressed it can result in noncompliance fines. Cod and biological oxygen demand bod the constructor. You might think a highly variable cod bod ratio is to be expected with industrial waste streams. The higher the bod value, the greater the amount of organic matter or food available for oxygen consuming bacteria. Iron and steel bod, cod, oil, metals, acids, phenols, and cyanide textiles and leather bod, solids, sulfates and chromium pulp and paper bod, cod, solids, chlorinated. Biochemical oxygen demand measures the quantity of oxygen consumed by microorganisms during the decomposition of organic matter.
Measurement of organic matter concentration organic matter in wastewater is heterogeneous suspended colloidal and dissolved organic matter. Biochemical oxygen demand definition of biochemical. Organics in wastewater may be refractory organics in wastewater are degradable. The most popular sum parameter in waste water analysis are the bod biochemical oxygen demand, cod chemical oxygen demand, tod total oxygen demand and toc total organic carbon. In most cases the special factor bod 5 is perceived as the bod, which requires a detailed definition 5 represents the 5 days analysis time34. Organic matter nonbiodegradable and biodegradable toc, cod, do, bod, bodu and serial bod dr. Cod or chemical oxygen demand definition the laboratory. Chemical oxygen demand cod vs biological oxygen demand bod. What is cod and bod in waste water treatment plant. Cod reduction and other wastewater treatment solutions from manufacturer beckart environmental. Fortunately, beckart environmental is here to help.
Wastewater treatment is designed to remove oxygendemanding substances as measured by fiveday biochemical oxygen demand, bod 5 or bod and solid particles measured as total suspended solids, or tss. Bod or biological oxygen demand is supposed to measure the amount of food or organic carbons that bacteria can oxidize. Cod or chemical oxygen demand is the total measurement of all chemicals in the water that can be oxidized. Bod analysis is similar in function to chemical oxygen demand cod analysis, in that. Biochemical oxygen demand an overview sciencedirect topics. Biochemical oxygen demand bod and chemical oxygen demand pdf. None of the alternatives provide a better assessment of the bioavailability of a waste like the bod test. May 14, 2014 biochemical oxygen demand bod and chemical oxygen demand cod both measure the quantity of organic compounds found in water. Atau sebaliknya, pada kasus pencemaran lainnya yang. Cod is chemical oxygen demand, measured by strong oxidation with dichromate, which oxidizes all organic compounds. However, another substance in wastewater leads to inhibition of bacteria that. Biochemical oxygen demand bod is the amount of dissolved oxygen needed i. Biochemical oxygen demand bod in wastewater i real tech. Difference between bod and cod compare the difference.
A defined microbial consortium can be formed by conducting a systematic study, i. The determination of chemical oxygen demand in waters and. The standard method for indirect measurement of the amount of pollution that cannot be oxidized biologically in a sample. Because the ultimate bod is so time consuming, the 5day bod has been almost universally adopted as a measure of relative pollution effect. Bod is a measure of, the amount of oxygen that require for the bacteria. Cod or chemical oxygen demand definition the laboratory people. Bod, chemical oxygen demand cod, total organic carbon.
If there is a large quantity of organic waste in the water supply, there will also be a lot of bacteria present working to decompose this waste. The document may be used as guidance for the reporting process under urban waste water treatment directive 91271eec. Those standards are called equivalent to secondary treatment standards. Biochemical oxygen demand bod and chemical oxygen demand cod both measure the quantity of organic compounds found in water. Oct 16, 2009 chemical oxygen demand is related to biochemical oxygen demand bod, another standard test for assaying the oxygendemanding strength of waste waters. Bod is defined as the amount of oxygen demanded by the microorganisms in the sewage for the. Standard method for indirect measurement of the amount of organic pollution that can be oxidized biologically in a sample of water. Bod, cod, toc and tod sum parameters in environmental. However, cod analysis is less specific, since it measures everything that can be chemically oxidized, rather than just levels of biologically oxidized organic matter. Biochemical oxygen demand or biological oxygen demand, is a measurement of the amount of dissolved oxygen do that is used by aerobic microorganisms when decomposing organic matter in water. Bod refers to the biochemical oxygen demand and cod is the chemical oxygen demand.
While the bod test is performed by using a population of bacteria and other microorganisms to attempt to duplicate what would happen in a. Cod or chemical oxygen demand is the total measurement of all chemicals. During the last century a huge amount of industrial wastewater was. While the bod test is performed by using a population of bacteria and other microorganisms to attempt to duplicate what would happen in a natural stream over a period of five days, the. What is the difference in bod, bod5, cbod and nbod, i am. Organics 2 university of georgia cooperative extension circular 922. Bod and cod are measures of the potential oxygen demand in an. Bod biochemical oxygen demand is supposed to measure the amount of food or organic carbons that bacteria can oxidize. Reddy thapar university patiala punjab 147 004 india 2. Biochemical oxygen demand bod, the amount of dissolved oxygen used by microorganisms in the biological process of metabolizing organic matter in water. On the other hand, cod refers to the amount of oxygen needed to oxidize all the organic and inorganic pollutants in water chemically. Biological oxygen demand bod is a measure of the oxygen used by microorganisms to decompose this waste. Industrial wastewater is one of the important pollution sources in the pollution of the water environment. Where there is water and wastewater exist the cod and bod, and is in a ratio with the variation mentioned above.
A special chemical is added to kill the autotrophic bacteria so nitrification is inhibited so that only the oxidation of cod occurs. There is no generalized correlation between the 5day bod and the ultimate bod. What is the relationship between the cod and bod values in. Bod can be measured in realtime with our bod analyzer to improve wastewater process control and plant efficiency. Biochemical oxygen demand bod is also sometimes referred to as biological oxygen demand, but the latter term is considered inappropriate by many scientists and engineers. These terms are widely used to define the microbial use or consumption i. What would be the bod 8 if the test were run at 15oc. Typical sources of bod are readily biodegradable organic carbon carbonaceous, cbod and ammonia nitrogenous, nbod. High bodcod is indirect indicator of the organic content ammonia is inorganic and creates an oxygen demand as it is converted to nitrate. Terms and definitions of the urban waste water treatment directive 91271eec compiled final version brussels, 16 january 2007 the document has been endorsed at the uwwtdrep working group meeting on 20 december 2006. Difference between bod and cod definition, test method. The key difference between bod and cod is that the bod is the oxygen demand of microorganisms to oxidize organic matter in the water under aerobic conditions while the cod is the oxygen demand to oxidize all the pollutants in the water chemically.
In this case, the demand for oxygen will be high due to all the bacteria so the bod level will be. In the presence of free oxygen, aerobic bacteria use the organic matter found in wastewater as food. If you continue browsing the site, you agree to the use of cookies on this website. To determine and measure of oxygen requirement of the sample waste water through chemical oxygen demand cod process.
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