Page 62 - Materials Chemistry, Second Edition

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Cleaner Production
needed to reverse this absurd equation. In other words, finding how whey could
be recovered and used would reduce the cost of end-of-pipe treatment and
save resources.

CP opportunity assessment
This structured implementation process is part of a systematic audit proce-
dure. According to Johansson (1992), the environmental audit consists of four
phases, which are informational group meeting, on-site meeting, plant walk-
through, and alternative methods. In the first three phases specialized staff
consisting of industrial consultants with the aid of a firm representative gather
relevant information. Then the industrial experts develop a preliminary assess-
ment for the possible solutions and alternatives. Some of these solutions may
require prior investigation before being implemented as will be discussed
during the implementation phase.
Investing in cleaner production to prevent pollution and reduce resource
consumption is more cost effective than continuing to rely on expensive
end-of-pipe solutions. Therefore, if the factory could conduct on-site recycling/
recovery for the whey, this would decrease its end-of-pipe treatment cost and
generate extra revenue. On the other hand, if the animal farm could use the
whey as an animal feed for ruminants as an input material instead of water
or molasses, this would reduce the use of natural resources in terms of water
and dry feed at an extra cost to the farm.

CP techniques implemented
Experimental phase
A cleaner production industrial audit is performed but some corrective meas-
urements need to be tested before implementation to insure that they satisfy
the technical, financial and environmental requirements. This is done first
on a laboratory scale by a research institute or qualified experts. In this case
the characteristic of the whey produced by Misr Company for Dairy and Food
was determined by conducting chemical, physical and nutritional analyses.
The aim of this laboratory work is to assess the nutritional value of the
whey against that of the molasses. The total nitrogen (%) for sweet whey,
whey permeate and cane molasses was found to be 1.3, 0.26 and 0.66 respec-
tively, and the digestible energy (%) was 1.86, 1.7 and 1.4 respectively. This
shows that whey has a higher nitration value than molasses.
Whey may cause health problems for animals if pH is below 4.5 or above
6
8.5, the microbial content is above (1 10 /100 ml) and the total coliform
exceeds (1/100 ml) for calves and (30/100 ml) for cows. Therefore, the aim of
this analysis is to check the whey against these values. The storage life of whey
was determined and the whey was found to be safe if used under certain
preservative conditions since pH may drop to 4.8 after storing fresh whey
permeate for 24 hours.