Biochemical Oxygen Demand (BOD) refers to the number of Oxygen that will be consumed if all the organics in one l of water were change by microorganism and protozoa.
The first step in mensuration frame is to get equal volumes of water from the realm to be tested and dilute every specimen with a noted volume of H2O that has been completely agitated to insure Oxygen saturation.
After this, an Oxygen meter is employed to see the concentration of Oxygen among one in every of the vials. The remaining phial is than sealed and placed darkly and tested 5 days later. frame is then determined by subtracting the second meter reading from the primary.
The vary of potential readings will vary considerably: water from an exceptionally clear lake would possibly show a frame of but a pair of ml/L of water. Raw waste could offer readings within the a whole bunch and food process wastes is also within the thousands.
Background data
Microorganisms like microorganism area unit to blame for rotten organic waste. once organic matter like dead plants, leaves, grass clippings, manure, sewage, or perhaps scraps is gift during a facility, the microorganism can begin the method of breaking down this waste. once this happens, abundant of the offered dissolved Oxygen is consumed by aerobic microorganism, robbing different aquatic organisms of the Oxygen they have to measure.
Biological Oxygen Demand (BOD) may be a live of the Oxygen employed by microorganisms to decompose this waste. If there's an outsized amount of organic waste within the facility, there'll even be plenty of microorganism gift operating to decompose this waste. during this case, the demand for Oxygen are going to be high (due to all or any the bacteria) that the frame level are going to be high. because the waste is consumed or distributed through the water, frame levels can begin to say no.
Nitrates and phosphates during a body of water will contribute to high Biological Oxygen Demand levels. Nitrates and phosphates area unit plant nutrients and may cause flora and alga to grow quickly.
When plants grow quickly, they additionally die quickly. This contributes to the organic waste within the water, that is then rotten by microorganism. This ends up in a high frame level.
When BOD levels area unit high, dissolved Oxygen (DO) levels decrease as a result of the Oxygen that's offered within the water is being consumed by the microorganism. Since less dissolved Oxygen is obtainable within the water, fish and different aquatic organisms might not survive.
Test Procedure
The frame check takes five days to complete and is performed employing a dissolved Oxygen check kit. The frame level is decided by scrutiny the DO level of a water sample taken right away with the DO level of a water sample that has been incubated during a dark location for five days. The distinction between the 2 DO levels represents the number of Oxygen needed for the decomposition of any organic material within the sample and may be a smart approximation of the frame level.
1. Take a pair of samples of water
2. Record the DO level (ppm) of 1 right away victimization the tactic delineate within the dissolved Oxygen check.
3. Place the second water sample in AN brooder in complete darkness at twenty deg.C for five days. If you do not have AN brooder, wrap the water sample bottle in aluminium foil or black electrical tape and store during a dark place at temperature (20 deg. C or 68 F).
4. when five days, take another dissolved Oxygen reading (ppm) victimization the dissolved Oxygen check kit.
5. compute the Day five reading from the Day one reading to see the frame level.
Record your final frame lead to ppm.
The first step in mensuration frame is to get equal volumes of water from the realm to be tested and dilute every specimen with a noted volume of H2O that has been completely agitated to insure Oxygen saturation.
After this, an Oxygen meter is employed to see the concentration of Oxygen among one in every of the vials. The remaining phial is than sealed and placed darkly and tested 5 days later. frame is then determined by subtracting the second meter reading from the primary.
The vary of potential readings will vary considerably: water from an exceptionally clear lake would possibly show a frame of but a pair of ml/L of water. Raw waste could offer readings within the a whole bunch and food process wastes is also within the thousands.
Background data
Microorganisms like microorganism area unit to blame for rotten organic waste. once organic matter like dead plants, leaves, grass clippings, manure, sewage, or perhaps scraps is gift during a facility, the microorganism can begin the method of breaking down this waste. once this happens, abundant of the offered dissolved Oxygen is consumed by aerobic microorganism, robbing different aquatic organisms of the Oxygen they have to measure.
Biological Oxygen Demand (BOD) may be a live of the Oxygen employed by microorganisms to decompose this waste. If there's an outsized amount of organic waste within the facility, there'll even be plenty of microorganism gift operating to decompose this waste. during this case, the demand for Oxygen are going to be high (due to all or any the bacteria) that the frame level are going to be high. because the waste is consumed or distributed through the water, frame levels can begin to say no.
Nitrates and phosphates during a body of water will contribute to high Biological Oxygen Demand levels. Nitrates and phosphates area unit plant nutrients and may cause flora and alga to grow quickly.
When plants grow quickly, they additionally die quickly. This contributes to the organic waste within the water, that is then rotten by microorganism. This ends up in a high frame level.
When BOD levels area unit high, dissolved Oxygen (DO) levels decrease as a result of the Oxygen that's offered within the water is being consumed by the microorganism. Since less dissolved Oxygen is obtainable within the water, fish and different aquatic organisms might not survive.
Test Procedure
The frame check takes five days to complete and is performed employing a dissolved Oxygen check kit. The frame level is decided by scrutiny the DO level of a water sample taken right away with the DO level of a water sample that has been incubated during a dark location for five days. The distinction between the 2 DO levels represents the number of Oxygen needed for the decomposition of any organic material within the sample and may be a smart approximation of the frame level.
1. Take a pair of samples of water
2. Record the DO level (ppm) of 1 right away victimization the tactic delineate within the dissolved Oxygen check.
3. Place the second water sample in AN brooder in complete darkness at twenty deg.C for five days. If you do not have AN brooder, wrap the water sample bottle in aluminium foil or black electrical tape and store during a dark place at temperature (20 deg. C or 68 F).
4. when five days, take another dissolved Oxygen reading (ppm) victimization the dissolved Oxygen check kit.
5. compute the Day five reading from the Day one reading to see the frame level.
Record your final frame lead to ppm.
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