Oxi 700

Oxi700

Oxi700 Respirometric BOD System

Respirometric methods provide direct measurements of the oxygen consumed by microorganisms from an air or oxygen-enriched environment in a closed vessel under conditions of constant temperature and agitation. Carbon dioxide produced metabolically by the bacteria is chemically bound by the potassium hydroxide solution contained in the seal cup in the bottle.

The result is a pressure drop in the system, which is directly proportional to the BOD value and is measured by the BOD sensor. The BOD level is then displayed directly in mg/l.

The BOD values are stored in the sensor memory and can be viewed on the large-format display at any time without the need for time consuming conversion using factors. This means that test series that end on a weekend can be evaluated during the following week.

The measurement period is user-selectable between 1 and 28 days.

Evaluation of measurements

If the measuring period is set at 24 hours, the Oxi700 BOD measuring system records a measurement once every hour. With a measuring period of 48 hours, the unit measures and stores a BOD value once every 2 hours. If the measuring period is between 3 and 28 days, one value is measured and stored each day.

Current values and stored values may be recalled at any time. The table above illustrates an example of BOD5 evaluation. The development of BOD over a period of 5 days is easily seen.