Online BOD analyser
Continuous BOD at the outlet, when the laboratory test takes three days
Biochemical oxygen demand (BOD) is the oxygen micro-organisms use to break down organic matter. The laboratory test incubates a sample for three days at 27 °C, so it cannot be continuous. Online, BOD is derived from the same UV–visible spectrum as COD, using a BOD:COD correlation set at commissioning against your own laboratory results for that outlet.
- SYZE-OCEMS-8P
- One of 8 parameters as standard
- CPCB
- HSPCB
- PPCB
At a glance
Supplied as part of the SYZE-OCEMS-8P, with all eight parameters as standard.
- Parameter
- BOD, biochemical oxygen demand
- Range
- 0–1000 mg/L, set to your consented limits
- Method
- Derived from the UV–visible spectrum with a BOD:COD correlation
- Instrument
- The multi-parameter optical probe of the SYZE-OCEMS-8P, which also gives the other optical parameters
- Reagents
- None
- Output
- RS485 Modbus to the SYZE data logger
- Reported to
- CPCB, HSPCB, PPCB and PHED
Keeping BOD readings right
- A correlation for your outlet
- Set at commissioning from your laboratory's BOD and COD results for the same samples.
- Rechecked when the effluent changes
- A new process, a new industrial load or a change in treatment alters the BOD:COD ratio; the correlation is then checked again.
- Reported with the others
- BOD goes to the boards with COD, TSS, pH and flow, as the boards and the NGT order require.
- Clean optics
- BOD depends on the same optical window as COD, so it is cleaned on the same schedule.
Questions
Are online BOD readings accepted by the boards?
BOD derived from the spectrum is how continuous BOD is reported in practice. The station is registered on the portals as part of the installation, and commissioning is complete only when live data is seen there.
How often is the correlation checked?
At commissioning, at the intervals in CPCB's guidelines, and whenever the effluent changes or a laboratory check shows drift.
The analyser and the other parameters
- Online water quality analyser (8 parameters)Our main product: eight parameters as standard, made in India
- COD analyserChemical oxygen demand measured continuously at the outlet, without reagents
- TSS analyserTotal suspended solids measured continuously, by optical absorption and scatter
- pH analyserpH at the outlet on its own port, with automatic temperature compensation
- TOC analyserTotal organic carbon from the same UV–visible spectrum, as standard
- Turbidity analyserHow clear the effluent is, measured continuously as scattered light
- TemperatureA PT100 sensor built into the optical probe
- FlowFlow turns concentrations into loads, and every OCEMS station reports it
Further reading
See it working
Send us a few recent laboratory BOD and COD results and we will tell you how the correlation is set.