
	Where results make sense

Topic: Biochemical oxygen demand

Related Topics

price elasticity of demand

aggregate demand

video on demand

Twenty One Demands

Demand pull inflation

biochemical oxygen demand

cross elasticity of demand

Induced demand

chemical oxygen demand

income elasticity of demand

demand paged

In the News (Mon 20 May 13)

EXECUTIVE POWER

Iran

ANALYSIS

Pakistan

Family compact

	4. Biochemical Oxygen Demand \| Project Watershed Central New York
		Biochemical oxygen demand (BOD) is a measure of the amount of oxygen that is utilized by microorganisms during the oxidation and break down of organic matter.
		Excessive inputs of nutrients and organic matter are a prime contributor to high BOD levels in streams (Mitchell and Stapp, 1997).
		Student or adult volunteers collect a water sample in a 60-ml BOD bottle by submersing the bottle for several seconds to allow all air bubbles to escape.
	www.projectwatershed.org /node/639 (539 words)

	Biochemical oxygen demand - Wikipedia, the free encyclopedia
		BOD - biochemical (biological) oxygen demand is a test used to measure the concentration of biodegradable organic matter present in a sample of water.
		BOD measures the rate of uptake of oxygen by micro-organisms in the sample of water at a fixed temperature and over a given period of time.
		The BOD test is carried out by diluting the sample with de-ionised water saturated with oxygen, innoculating it with a fixed aliquot of seed, sealing the sample (to prevent further oxygen dissolving in), and then placing it in the dark (to prevent photosynthesis and thereby the addition of oxygen).
	en.wikipedia.org /wiki/Biological_Oxygen_Demand (524 words)

	Chemical oxygen demand - Wikipedia, the free encyclopedia
		In environmental chemistry, the chemical oxygen demand (COD) test is commonly used to indirectly measure the amount of organic compounds in water.
		Because COD measures the oxygen demand of organic compounds in a sample of water, it is important that no outside organic material be accidentally added to the sample to be measured.
		The oxygen demand in the blank sample is subtracted from the COD for the original sample to ensure a true measurement of organic matter.
	en.wikipedia.org /wiki/Chemical_oxygen_demand (896 words)

	EPA > OWOW > Monitoring and Assessing Water Quality > Volunteer Stream Monitoring: A Methods Manual > ...
		Biochemical oxygen demand, or BOD, measures the amount of oxygen consumed by microorganisms in decomposing organic matter in stream water.
		The rate of oxygen consumption in a stream is affected by a number of variables: temperature, pH, the presence of certain kinds of microorganisms, and the type of organic and inorganic material in the water.
		One is tested immediately for dissolved oxygen, and the second is incubated in the dark at 20 C for 5 days and then tested for the amount of dissolved oxygen remaining.
	www.epa.gov /owow/monitoring/volunteer/stream/vms52.html (3714 words)

	Water Quality Monitoring: Biochemical Oxygen Demand (Site not responding. Last check: 2007-10-14)
		Biochemical oxygen demand is a measure of the quantity of oxygen used by microorganisms (e.g., aerobic bacteria) in the oxidation of organic matter.
		Oxygen consumed in the decomposition process robs other aquatic organisms of the oxygen they need to live.
		The biochemical oxygen demand is the difference between DO levels in the two samples, so the level of the original sample must be known.
	www.fivecreeks.org /monitor/bod.html (308 words)

	EEA - Themes - water - Biochemical oxygen demand in rivers (Site not responding. Last check: 2007-10-14)
		A high demand, therefore, can indicate that levels of dissolved oxygen are falling, with potentially dangerous implications for the river’s biodiversity.
		Biochemical oxygen demand is therefore one of the main parameters used in the Urban Wastewater Treatment Directive for controlling discharges.
		Improvements in wastewater management saw biochemical oxygen demand fall in all sizes of river during the early 1990s.
	themes.eea.eu.int /Specific_media/water/indicators/bod/index_html (365 words)

	Biochemical Oxygen Demand Laboratory (Site not responding. Last check: 2007-10-14)
		Oxygen consumed by inorganic compounds is also measured by this test, which is why it is referred to as biochemical oxygen rather than just biological oxygen demand.
		It is used as an index of the amount of organic pollution of the water and is routinely employed to measure the efficiency of wastewater treatment plants in removing organic matter from wastewater or in assessing the effect of effluents on the trophic status of natural waters.
		BOD is high in organically polluted waters and low in pristine water.
	www.lander.edu /RSFOX/415BODlab.html (1370 words)

	testing for biochemical oxygen demand
		As stated in the dissolved oxygen introduction, there are many factors that can affect the short-term levels of dissolved oxygen.
		To determine whether a dissolved oxygen test is closer to a long-term average or is closer to a short-term high or low, other tests should be performed and reported in conjunction with the DO test results.
		BOD is a measure of the aqueous molecular oxygen that is used for the microbial degradation of organic material and the chemical and microbial oxidation of materials such as sulfides, ammonia, nitrites, and iron (II) ion.
	www.fenwickfriars.com /creek/webpage/experimt/BOD/bod.html (799 words)

	Search Results for "Biochemical" (Site not responding. Last check: 2007-10-14)
		...The amount of oxygen required by aerobic microorganisms to decompose the organic matter in a sample of water, such as that polluted by sewage.
		Molecules may be broken down to gain their energy or to prepare them for disposal from the...
		The study of the biochemical constituents of fossil organisms.
	www.bartleby.com /cgi-bin/texis/webinator/sitesearch?FILTER=&query=Biochemical (260 words)

	Biochemical Oxygen Demand (BOD) Test
		In rivers with high BOD levels, much of the available dissolved oxygen is consumed by aerobic bacteria, robbing other aquatic organisms of the oxygen they need to live.
		One of the dissolved oxygen bottles should be flened or purchased as a "dark bottle." One approach is to wrap the bottle with fl electrical tape.
		The BOD measure is, the amount of oxygen consumed by organic matter and associated microorganisms in the water over a five-day period.
	www.bradwoods.org /eagles/bod.htm (708 words)

	Earth Force: Programs: GREEN: Biochemical Oxygen Demand (Site not responding. Last check: 2007-10-14)
		Biochemical oxygen demand is a measure of the quantity of oxygen used by these microorganisms in the aerobic oxidation of organic matter.
		Dissolved oxygen levels rise from morning through the afternoon as a result of photosynthesis, reaching a peak in the late afternoon.
		As organic pollution increases, the ecologically stable and complex relationships present in waters containing a high diversity of organisms is replaced by a low diversity of pollution-tolerant organisms with increasing populations.
	www.earthforce.org /section/programs/green/_bod (465 words)

	Biochemical Oxygen Demand (Site not responding. Last check: 2007-10-14)
		Significance: Biochemical Oxygen Demand (BOD) is defined as the requirement or demands for oxygen that matter, organic and chemical, places on water during the decay process or during chemical reactions.
		When testing for BOD, the first step is to collect equal amounts of water from the research waterway and dilute each of the samples (usually 2 or 3 equal sized containers) with the exact same amount of distilled water.
		Then the dissolved oxygen test for BOD5 or BOD7 is subtracted from the first dissolved oxygen test for BOD1, to give the result of the Biochemical Oxygen Demand test.
	www.switzerland.k12.in.us /watershed/bod.html (354 words)

	The Nuts and Bolts of Chemical Oxygen Demand
		Oxygen demand is an important parameter for determining the amount of organic pollution in water.
		Biochemical Oxygen Demand (BOD) is a definitive indicator of required treatment in wastewater, and estimating BOD is an important part of wastewater treatment process control.
		BOD testing uses microorganisms that consume oxygen while feeding on organic compounds in a wastewater sample over a five-day period.
	www.wwdmag.com /wwd/index.cfm?powergrid=rfah=\|cfap=&fuseaction=showArticle&articleID=4076 (973 words)

	BIOCHEMICAL OXYGEN DEMAND
		DO (dissolved oxygen) is measured initially and after incubation, and the BOD is computed from the difference between initial and final DO.
		Minimize reduction of BOD by analyzing sample promptly or by cooling it to near-freezing temperature during storage.
		BOD values that increase with time of adaptation to a steady high value indicate successful seed adaptation.
	www.oasisenviro.co.uk /biochemical_oxygen_demand.htm (3445 words)

	Science Project 2005
		The results of the experiment were that River water had the lowest BOD at an average of 1.93 mg/L, the waste before treatment had the highest BOD with an average of 1679.59 mg/L, and the treated wastewater was in the middle with almost a 10th of the BOD as before treatment.
		The highest average chemical oxygen demand was 2767 mg/L that was before treatment and again the lowest COD was the river water at 5.75 mg/L. The river had cleaner water than the wastewater before and after treatment.
		Biochemical Oxygen Demand is a measure of the oxygen needed for all of the organisms in a body of water to live.
	www.selah.k12.wa.us /SOAR/SciProj2005/BrittanyB.html (2726 words)

	Simulation of temperature, nutrients, biochemical oxygen demand, and dissolved oxygen in the Ashley River near ...
		Setting all the point-source loadings to advanced secondary treatment (10 milligrams per liter of ammonia-nitrogen (mg/L) and 20 mg/L of 5-day biochemical oxygen demand) decreased the total ultimate oxygen demand loading to the system by 28 percent and decreased the one-day mean dissolved-oxygen concentrations from the no-load condition by 29.9 percent or less.
		Setting all the point-source loadings to advanced treatment (2 mg/L of ammonia-nitrogen and 10 mg/L of 5-day biochemical oxygen demand) decreased the total ultimate oxygen demand loading to the system by 78 percent and decreased the one-day mean dissolved-oxygen concentrations from the no-load condition by 8.1 percent or less.
		Setting all the point-source loadings to reclaimed-use treatment (0.5 mg/L of ammonia-nitrogen and 5 mg/L of 5-day biochemical oxygen demand) decreased the total ultimate oxygen demand loading to the system by 91 percent and decreased the one-day mean dissolved-oxygen concentrations from the no-load condition by 5.2 percent or less.
	sc.water.usgs.gov /publications/wrir98-4150abs.html (389 words)

	Biochemical Oxygen Demand and Sewer Ponds - 1997-98
		The reasons scientists use BOD results are: 1) how to determine the approximate quantity of oxygen present, 2) to determine the size of the waste treatment facilities, 3) to measure the efficiency of some treatment processes, and the last reason 4) to determine compliance with the wastewater discharge permits.
		person must wait for five days with the BOD test and not later because within two days after the five carbonaceous oxygen demand starts to occur with the sample prepared, and nitrification starts occurring if the number of the nitrifying bacteria are presented in the sample.
		he decrease of BOD and the decline of and rise of DO depict the process known as self-purification, which is dependent on the rate at which oxygen is absorbed back into the stream, which, in turn, is dependent on the turbulence intensity and the water depth.
	www.cascadehs.csd.k12.id.us /advbio/97-98/biochemical.html (1982 words)

	Dairy Processing (Site not responding. Last check: 2007-10-14)
		The Environmental Protection Agency uses BOD levels to measure effluent strength and to establish effluent guidelines as required by the Federal Water Pollution Control Act.
		Biochemical oxygen demand is a measure of effluent strength in terms of the amount of dissolved oxygen utilized by microorganisms during the oxidation of organic components in the effluent.
		BOD is determined by incubating a suitable dilution of effluent in a standard dilution water or specific composition at 68°F. After incubation, the amount of dissolved oxygen consumed is obtained by titration and the results expressed as parts per million of BOD.
	drinc.ucdavis.edu /dairyp/dairyp9.htm (364 words)

	Oxygen Demand
		Biochemical Oxygen Demand is a measure of the oxygen requirement in microbial oxidation of organic substances contained in water.
		Chemical Oxygen Demand is a measure of the amount of oxygen required to oxidize organic and oxidizable inorganic compounds in water and wastewater.
		The amount of oxygen is provided by the addition of potassium dichromate.
	www.mimas.ac.uk /crossfire/webhelp/beilstein/brefhtml/eod.htm (104 words)

	Biochemical Oxygen Demand (BOD) (Site not responding. Last check: 2007-10-14)
		The BOD determination test is a measure of the amount of oxygen that is consumed by the bacteria as they decompose the organic components of waste and relies on the accurate determination of oxygen levels over a period of five days.
		The optional BOD probe (for the Model 9200 Dissolved Oxygen Meter) and associated components have been designed to facilitate the five day BOD test as defined in ISO 5815 and is used worldwide as a prime environmental test.
		Making use of the precision real-time-clock incorporated into the Model 9200 Dissolved Oxygen Meter and prompted by the instructional, menu based display, data is entered into the 100 storage location memory and after the five day incubation period, the BOD calculation is initiated, based on the formula:
	www.techneusa.com /do2/bod.htm (278 words)

	MASTER [MASTER]
		Thus, when this method is used, it is not possible to determine the 'before' and 'after' dissolved oxygen (D.O.) concentration for the same bottle.
		Regardless of the dissolved oxygen determination method used, it is good practice to base the results on replicate samples.
		The procedure followed when dilution is necessary is similar to that used for low BOD samples, except that the sample must be diluted prior to analysis.
	www-cee.engr.ucf.edu /classes/ees4111/Laboratory/BOD.htm (2080 words)

	Biological Oxygen Demand
		Although not identified in the causative factor matrix, biochemical oxygen demand (BOD) is an important water quality variable that should be included in water quality studies/monitoring.
		The amount of oxygen used in the metabolism of carbonaceous biodegradable soluble and non-soluble organic matter is termed biochemical oxygen demand (BOD) or carbonaceous biochemical oxygen demand (CBOD).
		BOD should be determined using nitrification inhibited samples to avoid double counting nitrogenous BOD (NBOD) (Tchobanoglous and Schroeder 1986).
	www.krisweb.com /stream/bod.htm (395 words)

	Biological Oxygen Demand (Site not responding. Last check: 2007-10-14)
		The amount of oxygen used in the metabolism of biodegradable organics is termed Biochemical Oxygen Demand (BOD).
		Therefore, BOD is a common indicator of the degree of contamination of natural water by organic pollutants.
		In this experiment, the BOD of samples taken from Lake Carnegie was compared to the BOD of sewage water taken from Stony Brook Sewage Treatment Plant.
	www.woodrow.org /teachers/help/temp_presentations/kim/biooxydemand.htm (299 words)

	biochemical oxygen demand on Encyclopedia.com (Site not responding. Last check: 2007-10-14)
		Mitochondria and diabetes: genetic, biochemical, and clinical implications of the cellular energy circuit.
		Oxygen consumption rates and metabolic enzyme activities of oceanic California medusae in relation to body size and habitat depth.
		Measurements of oxygen tension in native and transplanted rat pancreatic islets.
	www.encyclopedia.com /html/X/X-biochem-ox.asp (339 words)

	Oxygen Demand, Biochemical
		Biochemical oxygen demand (BOD) is a measure of how much organic pollution is in water.
		The BOD test measures the amount of dissolved oxygen in water that is used up due to the breakdown of organic pollutants, such as sewage, in a certain number of days.
		Oxygen in the water is replenished from the atmosphere through aeration, but if it is used up faster than it is replenished, the water becomes anaerobic (or hypoxic)—existing in the deficiency or absence of free oxygen.
	www.pollutionissues.com /Na-Ph/Oxygen-Demand-Biochemical.html (184 words)

	Oxygen Sag Models for Multiorder Biochemical Oxygen Demand Reactions (Site not responding. Last check: 2007-10-14)
		The empirical biochemical oxygen demand (BOD) equation is expressed as a multiorder reaction equation of order n then is combined with the dissolved oxygen mass balance equation to give the differential form of an oxygen sag equation for small rivers and streams for which dispersion can be neglected.
		The dissolved oxygen sag equation is verified with two published dissolved oxygen sag models by setting n equal to 3/2 (three-halves order BOD reaction), and n equal to 2 (second order BOD reaction).
		The proposed dissolved oxygen sag equation may be applied to test the BOD and dissolved oxygen models in large, complex numerical models, such as models used in developing total maximum daily load recommendations.
	www.pubs.asce.org /WWWdisplay.cgi?0410145 (217 words)

Try your search on: Qwika (all wikis)