Research - Bioremediation and Water Treatment

HBOD Probe

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The HBOD Probe uses a fluorescence method to measure the concentration of oxygen in the headspace of an HBOD test tube. The system is based on an optical fiber that illuminates a special thin-film coating at the end of the probe with blue light. The coating fluoresces and is quenched in proportion to the concentration of oxygen in the sample, and this signal is measured using separate optical cable. The device is a low-power system that is resistant to most interferences and is quite stable. Ordinarily, the tubes must be kept in the dark during sampling (using a special container drilled to fit the tubes). However, the probe can be made to work in ambient light. However, this increases the response time to one to two minutes (versus only seconds in the dark).

The HBOD probe specificiations:

Range: 0-100% oxygen in gas phase.
Response time: Uncoated tip: <1 s
Coated: 60-90 seconds
Compensation: Temperature
Interferences: None (from CH4, acetone, moisture, or CO2)
Resolution: 0.1% at high O2
0.01% at low concentration
Calibration: 2-point calibration (air; oxygen-free air)
Stability: <0.05% per day
Re-calibration: Beginning of a new HBOD Probe test
Probe temperature range: -80° C to +110° C
Storage conditions: no specific requirements
Probe lifetime: 1 year (reconditioning available)

System Components

- HBOD Probe and Software:
- Air Gage (to measure pressure, temperature and relative humidity)
- HBOD Tubes, tops, and crimper.
- Zero-air calibration tube
- Shaker table
- Incubator

 

Bruce E. Logan |  Department of Civil and Environmental Engineering | 231Q Sackett Building
Phone: 814-863-7908 | Fax: 814-863-7304 
The Pennsylvania State University, University Park, PA 16802