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Pollach, G.; Hein, W.; Rösner, G.:
The 2002 campaign - Agrana Austria (German). Zuckerindustrie 128 (2003) pp. 358-363. |
| Contents: Crop conditions - yields - beet quality - production data - extraction tower screens - press quality of pulp - natural biocides - microbiology of preliming - reduction of lime consumption - Limos lime dosing system - hardness determination for ion exchangers - rapid sugar house analysis |
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Rösner, G.; Pollach, G.:
Experiences with the application of antifoaming agents in Austrian sugar factories (German). Zuckerindustrie 122 (1997) pp. 787-793. |
| Abstract: Within the framework of a project, extending over several years, it was possible to reduce the consumption of antifoaming agents at the Agrana plants to less than 50 %. With the employment of special foam probes, on which bridging was avoided by rinsing with vapor condensate, the addition of antifoaming agents in juice purification was adapted to the real demand. In vessels with little turbulences, foam layers were destroyed by juice circulation through hollow-cone nozzles and additional probe dependent dosing of foaming agent. To control the extraction process, raw juice was aerated in a flow through vessel and antifoam agent was added, dependent on foam development in the vessel, for trial purposes. For the assessment of different defoaming formulations, beet juice, obtained by continuous pressing of heated sliced beet and such virtually free of defoamers, was frothed up under controlled conditions and titrated with thinned defoamer to a constand residual foam level. |
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Pollach, G.; Hein, W.; Rösner, G.:
The 2001 campaign - Agrana Austria, Agrana Hungary (German). Zuckerindustrie 127 (2002) pp. 362-366. |
| Contents: Yields - beet quality - production data - defective centrifugal - thick juice colors - press quality of pulp - hop add on - foam suppression technology - lime usage |
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Hein, W.; Pollach, G.; Rösner, G.:
Austrian experience in producing sugar from unpurified beet juice. Int.Sugar J. 98 (1996) pp. 52-55; 91-94. |
| Abstract:
This paper summarises experience in Austria of sugar manufacture from unpurified raw juice. Part one gives the results of a project on combined production of white sugar and ethanol. The idea was to concentrate raw juice, followed by crystallisation (evaporation crystallisation). The run-off was intended for alcohol production, whereas the sugar concentrate was processed to white sugar. The concentration of raw juice was initially impeded by scale formation on the evaporator tubes but this was improved by adding small amounts of soluble Ca salts. The "raw juice sugar" obtained from the concentrate showed purities of 97-98, but was turbid in solution. Liming and carbonatation of the dissolved sugar gave melted liquors from which white sugar could be crystallised. The filterability depended largely on the quality of the raw juice sugar. Part two describes the production of "Vollzucker" (whole sugar) from unpurified beet juices. The scaling problem was overcome by employing a special evaporator type - metallic particle fluidized bed with flash evaporation. The syrup thus obtained has a shelf life of years, provided a certain dry substance range is kept and the head space is filled with protective gas. A free flowing product can be obtained by spray drying, but for this the content of glucose and fructose must not exceed certain limits. |
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Pollach, G.; Hein, W.; Berninger, H.:
Calculation of saturated molasses purities (German). Zuckerindustrie 118 (1993) pp. 785-790. |
| Abstract: With the aim of simplifying formulas for the calculation of saturated molasses purities, it is proposed to work on the basis of "normal temperature relationships" instead of temperature-independent "ratios of ratios". The calculation of molasses data for a given temperature then proceeds not via a single sucrose solubility number, but via pairs of solubility numbers. In that way, the familiar saturation formula can be mathematically transformed, without changing the results. If saturation equations are to take account of the nonsugar composition, in addition to temperature and the nonsugar:water ratio, it is clearer to formulate a normal temperature equation with values related to nonsugar instead of values related to water. Based on 47 analyses of "normal" and "Quentin" molasses, a multiple regression with a correlation coefficient of 0,992 was obtained. This equation, valid for 50°C, in which all values are related to nonsugar, calculates sugar (per nonsugar) from water and earth alkalies. An equation for the calculation of molasses purities found in the literature was transformed and compared with the results. There was good agreement in the case of normal molasses, whereas for Quentin molasses there were one-sided divergences of up to 2 purity points. |
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Pollach, G.:
"Whole sugar": Technological aspects (German). Zuckerindustrie 117 (1992) pp. 711-714. |
| Abstract: Based on the requirements to be met by "whole sugar", a sweetener manufactured from sugar beets which preserves the natural plant substances, the combined raw juice extraction process, raw juice concentration, storage of the concentrated raw juice, and its drying are described. Special attention is given to measures to prevent scale formation during evaporation and factors affecting taste, appearance and the free-running quality of the product. The results of developmental work from the laboratory stage to commercial introduction are presented. Also covered are the process of water evaporation, composition of the scale formed during evaporation, sorption isotherms, and analytical data of the spray-dried "whole sugar". |
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Rösner, G.; Pollach G.:
Studies of scale formation with the aid of laboratory evaporators (German). Zuckerindustrie 111 (1986) pp. 125-128. |
| Abstract: Two small-scale evaporators are described which can be used for scale formation studies on a laboratory scale. The vessels were successfully applied to the study of scale formation during concentration of sugar beet raw juice and sorghum raw juice. |
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Hein, W.; Pollach G.:
Analytical methods for control of sweet sorghum processing - juice extraction sector (German). Zuckerindustrie 110 (1985) pp. 291-296. |
| Abstract: Methods are reported for the determination of dry solids, fibre, sugar and starch in sweet sorghum and sweet sorghum bagasse which have been successfully applied to monitoring of pilot trials with sweet sorghum. These consisted partly of adapted methods suited to the sorghum material and partly of new methods devised. In addition, details are given of sampling or sample preparation and of the reproducibility of the individual determinations. |
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Pollach, G.; Gratzl, M.:
Development and operation of an industrial unit for biological determination of the sugar
content in pulp press water (German). Zuckerindustrie 104 (1979) pp. 940-942. |
| Abstract: A unit has been designed for sugar determination in press water and raw juices based on sugar conversion to acid by highly thermophilic micro-organisms. It represents a further development of a previously described prototype for this procedure. Use of a micro-processor permits attainment of the requisite confidence level, extensive automatic disturbance diagnosis and flexible signal processing with tolerance controls. |
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