8589356380

V. Tuzhilkin. K. Urazbayeva. R. Alibekov. SEMIC0NT1NU0S SUGAR CR YSTALUTA TION

1)    formation of purpose, assignment and application of the developed technology;

2)    analysis of a priori information about the method or process, to obtain additional information;

3)    the generation of ideas for solving the problem, the essence and distinctive features;

4)    description of the regimes and methods of implementation;

5)    scientific justification based on

mathematical modeling, laboratory, pilot testing,    obtaining theoretical    and

experimental information;

6)    formation merits of the proposed technology restrictions;

7)    determination the effectiveness, technical

feasibility and    opportunities    for

improvement of the proposed technology.

RESULTS AND DISCUSSION

The essence of this technology consist in the elimination of the thickening stage boils down to product labile State, input to the vacuum apparatus ready massecuite equal to the original set of massecuite in vacuum apparatus, and creating an environment of growth in the metastable zonę of crystals increasing until availability to descent.

Thus,    semi-continuous

crystallization process excludes three important steps:

1.    Concentration of the boiled product till initialing of crystals;

2.    Forming of crystallization centers;

3.    Growing of crystals not morę than sizes

0. 2.-*• 0,3 mm.

Consequently,    semi-continuous

crystallization processes is altemative variant and continuous sugar crystallization.

Taking to attention other possible Solutions, there can assume that currently are formed seven directions of industrial implementation of the proposed technology, namely:

1.    Preparation of crystal sugar on the basis of the same massecuite.

2.    Crystallization by using artificially prepared massecuite.

3.    Crystallization by using a bittem.

4.    Crystallization of sugar with syrup thickening stage transfer till a labile condition for separate stage evaporation.

5.    Crystallization with massecuite selection of previous or subsequent stages.

6.    Crystallization of sugar with sequential constriction of massecuite by the crystallization stages.

7.    Combined methods.

Further it will be considered the basie scientific principles of this technology.

The technology of obtaining of sugar on the crystal basis of the massecuite.

The core of the concentration of massecuite method consists in the boiled thickening product to a labile State and forming of centers of crystallization in quantity exceeding on the typical technology the number of crystallization centers in 2 times. After reaching the volume of massecuite at least twice the volume of the initial set of boiled product, it selects a half of massecuite obtained in another vacuum apparatus. Then, in both vacuum apparatus decrease a boiling point massecuite at 6-7 ⁰ C, with increasing the vacuum from 80 to 85 kPa, and under these conditions the crystals continue to inerease until massecuite ready to descend into the crystallizer.

Scientific substantiation of the proposed method for crystallizing sugar is the formation of twice the number of crystals (10-12 pieces on 1 mm instead of 5-6 pieces per 1 mm) inereases the ratę of mass growth by growing the surface area of crystallization. Simultaneously, at this stage of crystallization of sugar quickly reach compliance ratę of crystal growth and evaporation.

Lowering the temperaturę of boiling massecuite at 6-7 °C at constant temperaturę heating steam, the temperaturę difference inereases and enhances heat transfer.

Both factors - increasing of quantity of crystals and decreasing of temperaturę -

12    Journal of Industrial Technology and Engineering, 2012, 2(3): 11-18