الفهرس 
ACKNOWLEDGMENT
METHODS OF PURIFICATION AND CALER JUICE SPECIFICATIONOnly 14 pages are availabe for public view
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Abstract
Abstract
Scales in sugar industry considered as one of the huge problems
which still faced the development of the industry. This thesis
conducted to overcome two of the scales deposition problems.
First one is the scales which deposited on the surfaces of evaporator
tubes, these scales were accumulated on the internal surface of the
evaporator tubes forming an insulating layer that reduces heat
exchange between juice and steam. This requires other procedures
such as stopping the evaporators, cleaning and removing the sediment,
and all these steps obstruct the industrial process. Our new approach to
overcome this problem depends upon minimizing the problem in its
source. That was carried through a new method of cane juice
purification, which targeting to obtain a clear juice without any sulfur
content, and also with the lowest residual of calcium, besides other
good specifications.
In this method a mixture of hydrogen peroxide and calcium hydroxide
was used to treat an acidified mixed juice, then the treated juice
subjected to flotation clarification, depending upon the internal
chemical flotation phenomena which occurred in case of adding a
mixture of hydrogen peroxide and calcium hydroxide to the raw cane
juice.
In this point, work was done by testing the optimum conditions to
cause flotation, like pH, temperature, the way of addition, additives.
But the suitable conditions for flotation are not satisfactory to obtain a
clear juice with good specifications. So the optimum conditions to
obtain a clear juice with a good specification was studies. All these last
conditions were determined in a batch laboratory work. The net results
of the batch trials were used in contentious trials in a half industrial
plant, and the final conditions and results were defined. Results show
very positive indicators correspond to the target, that the clear juice not
only contain a small amount of calcium and without any sulfur content,
but also has a higher content of sucrose and less amount of ashes.
Comparing the new method results with the corresponding results of
the traditional methods used in the factories show the technical
benefits. Also a financial feasibility study was conducted and compare
them with that of traditional purification method, that to cover the
subject from all respects.
Abstract
iv
In the second part of this thesis, a problem of scale deposition on the
central juice tube of clarifiers was studied and solved. In this case, the
tube was completely clogged with deposits, and due to the vertical
position of the tube at the center of the clarifier, the traditional way of
cleaning cannot be used. So we conduct using a new chemical reagent
which success in cause fragmenting to the deposits. This reagent was a
mixture of hydrogen peroxide and sodium hydroxide, which added in a
defined rule, results were obtained around a period of days.
The common factor in both of the two thesis parts is the advantage of
Alkaline decomposition of hydrogen peroxide, which cause an
evolution of singlet oxygen and activation energy. Alkali in the first
case was calcium hydroxide which plays the main rule in juice
purification, while in the second case alkali was sodium hydroxide,
which the famous chemical cleaning agents in the field of evaporator
scales cleaning.