Abstract:
The two important parameters used in estimating the degree
of organic pollution in waste waters are the biochemical
oxygen demand (BOD) and the chemicaloxygen demand (COD).
The determination of BOD is tedious and time consuming.
Its precision is poor since it depends on biochemical
factors. But the determination of COD is usually precise,
time saving and is not dependent on biochemical factors.
The main objective of this research study was to
investigate the possible existence of any consistent
correlation between BOD and COD for waste waters from
different food processing industries. As a preliminary
study, synthetic samples of water containing glucose and
phthalate were analysed separately. The existence of a
significantpositive correlation between BOD3 and COD for
two synthetic samples was observed. The correlation
coefficient (r) of glucose was found to be 0.97 and that
of phthalate 0.96. No correlation between viable bacteria
counts and BOD3 was observed.
The correlation coefficients were also obtained for
samples of effluents from three different food industries,
namely, non alcoholic carbonated beverage with an ice cream
factory (r=0.87), fruit and vegetable processing factory
(r=O.93) and dairy product factory (r=0.89).
As a correlation existed between BOD3 and COD, an estimate
of BOD) could be obtained in a few hours through the determ1nationof COD and that would lead to a substantial
reductionof the time required, the man power and the cost
