Biochemical oxygen demand tests

Logan, B. E. and Patnaik, R., A gas chromatographic-based headspace biochemical oxygen demand test, Water Environ. Res., 69(2), 206-214, 1997. 

Biochemical oxygen demand tests with aqueous culture systems [45] can be used to measure the volume of carbon dioxide liberated from the mineralization of a substrate. Ohkawa et al. [22] used this method to follow the mineralization of fibers of the polyion complexes of chitosan-gellan and poly(L-lysine)-gellan. Filamentous fungi were used in this investigation and carbon dioxide release was observed. 

The amount of oxygen used in the degradation process is called the biochemical oxygen demand (BOD). A standard test has been devised to measure BOD in which the oxygen utilized by microorganisms in contact with the wastewater over a 5-day period at 20°C is measured. 

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. 

It has been reported that whilst the dilution bottle method for biochemical oxygen demand yields satisfactory results on fresh and low saline waters, a discrepancy exists when the test is performed on waters containing elevated levels of sodium chloride and other salts. 

Table I shows the five-day biochemical oxygen demand (BOD5 ) of some poly(sodium carboxylate)s and poly(vinyl alcohoDs (PVA). The BOD5 test according to JIS K 0102 is only an indication of susceptibility of products to biodegradation, but the test is often an useful tool for rapid screening. As shown in Table I, PMLA and...

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]. 

One of several oxygen consumption tests (such as biochemical oxygen demand, BOD) to determine biological/chemical contamination level of a water sample. Usually a laboratory chemical test or increasingly measured with equipment, and designed as indicator of inorganically originating contamination such as phosphate. 

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. 

Also the traditional BOD5 tests (e.g. the EU C.5 test) may demonstrate whether a substance is readily biodegradable. In this test, the relative biochemical oxygen demand in a period of 5 days is compared to the theoretical oxygen demand (ThOD) or, when this is not available, the chemical oxygen demand (COD). The test is completed within five days and consequently, the pass level defined in the proposed hazard classification criteria at 50% is lower than in the ready biodegradability tests. 

ISO 10707 (1994). Water quality - Evaluation in an aqueous medium of the ultimate biodegradability of organic compounds - Method by analysis of biochemical oxygen demand (closed bottle test)... 

The state is assessing the performance of a particular wastewater treatment plant by determining the biochemical oxygen demand (BOD) of its effluent (see Section 2.5). An inspector collects seven replicate samples of the plant effluent and submits them to a water-testing laboratory. The laboratory reports the following results ... 

---