Biochemical oxygen requirement

The dispersion of harmful substances in water can likewise be represented mathematically via the geometry of flow and the ensuing chemical and physical processes [7-52], (7-53), [7-54J. Thereby the description of the oxygen content, biochemical oxygen requirement (BSB), and water temperature which are essentially characteristic for the state of the water, are of the utmost importance. On the basis of these model computations, the state of the water emerges in the shape of longitudinal profiles and time profiles. 

Biochemical Oxygen Demand. The biochemical oxygen demand (BOD) test is an empirical determination of the oxygen requirement of a sample. It is most often appHed to wastewaters, industrial effluents, and poHuted waters. The decrease in the dissolved oxygen concentration resulting primarily from biological action is measured after storage for 5 d at 20°C. 

Nutrients can be classified into three groups based on levels required in waste treatment systems. These are given in Table 9. The major nutrients can be identified from the generalized biomass formula (Ceo Hg2 O23 Ni2 P). The actual quantity needed depends on the biochemical oxygen demand (BOD) of the waste. The higher the BOD the greater the quantity of cells produced. The minor and trace nutrients are needed in small quantities and are given in terms of concentration because these are the levels needed in solution to force the small amount required inside the cell across the cell-wall membrane. 

Applicable, relevant, and appropriate requirements Agency for Toxic Substances and Disease Registry Biochemical oxygen demand... 

Biochemical oxygen demand (BOD) is one of the most widely determined parameters in managing organic pollution. The conventional BOD test includes a 5-day incubation period, so a more expeditious and reproducible method for assessment of this parameter is required. Trichosporon cutaneum, a microorganism formerly used in waste water treatment, has also been employed to construct a BOD biosensor. The dynamic system where the sensor was implemented consisted of a 0.1 M phosphate buffer at pH 7 saturated with dissolved oxygen which was transferred to a flow-cell at a rate of 1 mL/min. When the current reached a steady-state value, a sample was injected into the flow-cell at 0.2 mL/min. The steady-state current was found to be dependent on the BOD of the sample solution. After the sample was flushed from the flow-cell, the current of the microbial sensor gradually returned to its initial level. The response time of microbial sensors depends on the nature of the sample solution concerned. A linear relationship was foimd between the current difference (i.e. that between the initial and final steady-state currents) and the 5-day BOD assay of the standard solution up to 60 mg/L. The minimum measurable BOD was 3 mg/L. The current was reproducible within 6% of the relative error when a BOD of 40 mg/L was used over 10 experiments [128]. 

The Biochemical Oxygen Demand (BOD) is an important parameter for waste-water monitoring. It gives information about the biodegradable organic pollution in wastewater. The main disadvantage of the conventional BOD-method is the required extended investigation time, which for example takes five days for... 

Biochemical Oxygen Demand (BOD) The amount of oxygen required by bacteria stabilize decomposable organic matter under aerobic conditions. 

BOD Sensor. The biochemical oxygen demand (BOD) test is one of the most widely used and important tests in the measurement of organic pollution. Since the BOD test measures biodegradable organic compounds in waste waters, it requires a long incubation period (5 days at 20C). Therefore a simple and reproducible method for estimation of 5-day BOD is required for pollution control(17). 

Biochemical oxygen demand (BOD) is arguably the oldest total parameter used for the characterization of water quality. It was introduced in the first decade of the twentieth century as a test for the organic pollution of rivers. BOD is the amount of oxygen in mg L 1 required for the oxidation of the organic matter contained in water by biological action under standardized test conditions (usually a temperature of 20°C and an incubation time of 5 days).8 9 The test is often used to evaluate the efficiency of wastewater treatment processes. 

Biochemical Oxygen Demand (BOD) estimation is based on a biodegradation. It is defined as the potential for removal of oxygen from water by aerobic heterotrophic bacteria which utilize organic matter for their metabolism and reproduction (Dupuit, 2006). Thus, it can be also considered as a biological parameter. This test requires a period of incubation (several days) at a controlled temperature in a sealed bottle in... 

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