Biochemical Oxygen Demand

What does Lovibond’s Oxi Direct BOD System have to do with Beer?

A little bit of light reading about Jospeh Williams Lovibond..

Joseph Williams Lovibond 1833-1918
Joseph Williams Lovibond 1833-1918

Joseph Williams Lovibond (1833–1918) was a British brewer who developed the world’s first practical colorimeter as a means of ensuring the high quality of his beer. He was the originator of the Degrees Lovibond scale.

In 1885 he founded a company, The Tintometer Limited, to manufacture his colorimeter which was called the Lovibond Comparator. The company still exists and still produces an updated version of the Lovibond comparator.

Oxi-Direct BOD System

OxiDirect BOD system
OxiDirect BOD system

 

Biochemical Oxygen Demand (BOD) BOD – biochemical oxygen demand – is an expression for the quantity of oxygen required for biological degradation of organic matter in a waste water sample. BOD measurement is therefore used as a basis for the detection of biologically degradable organic matter in water. The difference between BOD and chemical oxygen demand (COD) is that COD additionally registers biologically non-degradable organic matter.

BOD measurement is therefore an important measurement of the effects of domestic and industrial waste water on sewage plants and outflow points.

Manometric, respirometric BOD measurement using the Lovibond® OxiDirect (Camlab CW7000 BOD System)

The Camlab CW7000 BOD System  allows precise measurements of BOD based on the manometric principle. Manometric respirometers relate oxygen uptake to the change in pressure caused by oxygen consumption while maintaining a constant volume. Thanks to the modern integral pressure sensors it is no longer necessary to use mercury for pressure measurements.

The CW7000 sensor system is a six sample system that allows precise measurement of BOD based on the manometric principle.

  • Direct display of BOD in mg/l
  • User selectable measuring period of 1 to 28 days
  • Mercury free
  • Each position is independent so individual samples can be monitored

Manometric respirators relate oxygen uptake to the change in pressure caused by oxygen consumption while maintaining a constant volume.

BOD Principle

OxiDirect Principle

Respirometric methods provide direct measurements of the oxygen consumed by microorganisms from an air or oxygen-enriched environment in aclosed vessel under conditions of constant temperature and agitation. Carbon dioxide produced metabolically by the bacteria is chemically boundby 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 Lovibond® BOD sensor. The BOD level is then displayed directly in mg/l. The BOD values are stored in the sensor memory and can be called up 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 Sunday can be evaluated during the following week without any problem. The measurement period is user-selectable between 1 and 28 days to suit the application. While short measurement periods are useful for scientific applications, standard BOD measurements typically extend over a period of 5 days – and manometric determination of OECD, for example, generally takes place over a period os 28 days.

Range mg/l BOD      Sample Volume ml
0– 40                                  428
0– 80                                  360
0– 200                               244
0– 400                               157
0– 800                                 94
0–2000                               56
0–4000                               21.7

Applications – waste water, determination of biological activity, waste water treatment plants, analytical laboratories, science & research.

For more information click here

One thought on “What does Lovibond’s Oxi Direct BOD System have to do with Beer?

  1. please how can I measure the BOD for industrial wastewater by OxiDirect instrument. what is the nutrient and its concentration and volume.What is the volume of seeds. The size of industrial wastewater sample that I must added .
    thank you

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