The papers presented at the Meeting are listed below, linked to an abstract of the paper. In the future it will be possible to request a copy of each paper while reading the abstract.
#770 Modeling of Bulk Raw Sugar Stockpiles
#771 Colour Measurements In Raw and Affined Sugars
#772 Modification of the Carbonatation Process at Al Khaleej Sugar LLC
#773 Sugar Decolourisation With Alkali Regenerated Activated Carbon: Pilot Plant Evaluation at the Malelane Refinery
#774 Experience in the Operation of an Ion Exchange Plant and Improvements in the Biological Treatment of the Regenerants
#775 Microwave Concentration Measurement For Process Control in the Sugar Industry
#776 Symposium - A. Affination & Recovery Operations - B. Safety [NO ABSTRACTS]
#777 Applications of X-Ray Fluorescence to Sugar Processing
#778 An Investigation of Sucrose Solubility and Molasses Exhaustion Using Nuclear Magnetic Resonance Spectroscopy
#779 Assessing the role of Polyphenoloxidase in Extract Oxidation Darkening
#780 Polarisation of Raw Sugar Without Basic Lead Acetate: International Collaborative Test
#781 A New Clarifying Reagent For Polarization Analysis of Sugar Solutions
#782 Al Khaleej Sugar - A Water Efficient Refinery
#783 ERP's in the Sugar Industry - Central El Palmar Business Model
#784 Review of Modern Types of Silos for White Sugar
#785 Diversification Program at Taiwan Sugar Corporation
#786 Recent Developments and Applications of In-line Colour Measurements of Crystalline Sugar
#787 Experiences with new Batch Centrifugal Concept
#788 Characterisation of Colorants in Sugar Industry
#770 MODELLING OF BULK RAW SUGAR STOCKPILES
O. L. Crees, Queensland Sugar Corporation, Australia
CHASM is a mathematical package developed in Australia by CSIRO to model the stacking and reclaiming of bulk solids in stockpiles. The author has applied the model to the stacking and reclaiming of raw sugar in the bulk sugar storage facilities in Queensland. The raw sugar inventory has been modelled and tracked through stacking and reclaiming operations for an entire season. Using laboratory data from a program of sampling and analysis, the quality of sugar delivered to customers by road and ship has been predicted and compared with actual results.
The paper will describe the use of the model at one of Queensland's seven bulk sugar terminals and its validation by reference to actual data from normal operations at the terminal.
#771 COLOUR MEASUREMENTS IN RAW AND AFFINED SUGARS
Michel Mabillot, Beghin-Say, Nantes Refinery, France
Application of ICUMSA measurement at 420 nm is commonly used in laboratory to the washed sugar coming out of the affination centrifugals.
Works carried out at Beghin-Say Nantes refinery, aimed to establish an accurate measurement and rapid communication of colour characteristics.
A basic laboratory colorimeter was firstly used for stationary samples of different raw sugars and brown dry affined sugars. Laboratory works were done with a wide range of colour from very low coloured washed sugar to raw sugar entering into the refinery.
Absolute colour measurements were performed with values expressed by the L*a*b* and L*C*II* colour-coordinate systems, and statistical correlations with ICUMSA method have been determined.
Secondly, an on-line colour instrument, based on real-time reflectance measurement, was tested on a dry washed sugar, on which the colour control in solution form doesn't match perfectly with visual specifications. Currently, the continuous measurement of colour is used to monitor affination centrifugals with a good accuracy.
Details of operational procedures and results obtained are reported.
#772 MODIFICATION OF THE CARBONATATION PROCESS AT AL KHALEEJ SUGAR LLC
Jamal Al Ghurair, A. L. Longakit, S. Pachpute, Al Khaleej Sugar LLC, U.A.E.
Carbonatation has been used by some sugar refineries for almost 100 years now inspite the cleaning of the flue gas before compression is troublesome; the lime preparation is dirty and difficult to maintain; and the disposal of the carbonated cake is a problem.
The paper discusses the stages of the modification of the carbonatation process and the direct effect to its performance as well as to the filtration station at Al Khaleej Sugar (AKS) refinery located in Dubai, United Arab Emirates. The AKS plant is the largest and the most modern sugar refinery in the Middle East with a designed melt rate of 100 ton per hour of raw sugar. It employs the Distributed Control System and Programmable Logic Controllers for the whole refining process allowing only (7) technicians per shift to operate the whole plant.
The original set up of the carbonatation process is composed of two parallel CO2 scrubbing towers and two lines of three carbonator columns with individual recirculation pumps.
The following are the modifications of the carbonation station starting from the scrubbing of the flue gas to the CO2 gassing of the remelt liquor.
The experiences at AL Khaleej Sugar (AKS) refinery confirm that the modification undertaken significantly improved the performance of the carbonatation process as well as to the whole refinery plant, which consequently improved the color removal; improved filtration rate and saved power consumption due to the elimination of the recirculation pump.
#773 SUGAR DECOLOURISATION WITH ALKALI REGENERATED ACTIVATED CARBON: PILOT PLANT EVALUATION AT THE MALELANE REFINERY
M. Moodley, Transvaal Sugar Limited, South Africa, E Staal and M. Scholten, Norit - Netherlands, and M. Heering, Chemimpo, South Africa
A new process for fine liquor decolourisation with activated carbon (SPARAC process) was evaluated at the Malelane refinery. The exhausted carbon was regenerated with sodium hydroxide, instead of thermal regeneration. These decolourisation trials were performed on fine liquor with a four column pilot plant supplied by Norit. Two trials were carried out with the first lasting 124 days and the second 272 days. During trial one the carbon was exhausted after thirteen regenerations. The trial was stopped and the spent carbon was analysed. The results of the tests showed that the fouling of the carbon was due to the build up of calcium. Therefore it was decided that for the second trial an acid washing step be introduced during the regeneration cycle. The introduction of the acid wash during the regeneration has improved the life of the carbon. The carbon has undergone seventeen regenerations and the performance has decreased slightly.
#774 EXPERIENCE IN THE OPERATION OF AN ION EXCHANGE PLANT AND IMPROVEMENTS IN THE BIOLOGICAL TREATMENT OF THE REGENERANTS
Peter J. Dibella, Manildra Harwood Sugars, Australia
The Manildra Harwood Sugars refinery uses ion exchange resin as the main decolourisation step. The resin plant has a high throughput and achieves good results with low costs of operation. The spent caustic brine regenerant is treated biologically in an activated sludge effluent treatment plant prior to discharge through a licensed outlet.
The pH adjustment of the waste caustic brine regenerant prior to biological treatment was originally achieved by using concentrated sulphuric acid and sodium hydroxide. This process was difficult to control, required high levels of monitoring and was hazardous due to the nature of the chemicals.
The neutralisation process was modified to liquid carbon dioxide in 1997. This resulted in a simpler, more automated, cheaper and safer process. The performance of the effluent treatment plant has also markedly improved.
The treatment and disposal of the excess sludge was also improved to allow for automation. This involved the de-watering of the sludge on a rotary wedge wire screen and the incineration of the de-watered sludge in the boiler furnace.
This paper describes the operation of the ion exchange plant and details the improvements made in treating the waste regenerant stream in an activated sludge treatment plant.
#775 MICROWAVE CONCENTRATION MEASUREMENT FOR PROCESS CONTROL IN THE SUGAR INDUSTRY
Karl-Heinz Theisen, Tim Diringer, pro/M/tec Theisen GmbH, Germany
A new concentration measurement based on microwave technology was introduced to the sugar industry in 1996. Various installations have underlined the accuracy and easy handling of this measuring technique. Using the microwave technique for concentration measurements in the classical evaporation crystallisation process, there is no need for temperature compensation. Moreover the measurement is not influenced by purity changes of the mother syrup.
Trials in a refinery have shown that the standard deviation of the on line measurement in comparison to the laboratory is only +/- 0.24% WDS for 32 samples taken over a whole strike within a range of 72-92 % WDS.
The microwave concentration measurement is an indirect measuring technique based on transmitting and receiving a microwave signal through the sugar syrup or massecuite. The transmitted signal is partly absorbed by water molecules, which causes a change of the received microwave signal. Due to the fact that water has a much higher dielectric constant than most dry substances the change of the microwave absorption correlates to the water content of the syrup or massecuite. Therefore the microwave density measurements offers the possibility to indicate the total dry substance of a liquor or a massecuite during the whole crystallization process.
#776 SYMPOSIUM - A. AFFINATION & RECOVERY OPERATIONS - B. SAFETY- No abstracts at this time
#777 APPLICATIONS OF X-RAY FLUORESCENCE TO SUGAR PROCESSING
Stephen J. Clarke, Florida Crystals Corporation, U.S.A.
X-Ray fluorescence is a non-destructive analytical procedure that requires minimal or no sample preparation and is capable of quantifying all elements with atomic number above and including magnesium. The method does not distinguish between the chemical form in which the element is present, e.g. phosphorus as organic or inorganic phosphate and sulfur as sulfate or sulfite. A bench-top instrument has been used to measure simultaneously the levels of magnesium, calcium, potassium, sulfur, silicon, phosphorus and chlorine in raw sugars, cane, cane juice, syrups and molasses, evaporator scale, etc.. An interesting application is to measure affination efficiency, or the removal of the molasses film on raw sugar. Similarly, raw sugar with poor filtering characteristics often shows a higher level of calcium in the molasses film. Slices of cane have been analyzed directly to compare elemental levels in nodes and inter-nodes. Ion-exchange resins may be analyzed directly to measure the levels of counter-ion present. Examples of each of these applications, and others, will be presented.
#778 AN INVESTIGATION OF SUCROSE SOLUBILITY AND MOLASSES EXHAUSTION USING NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY
Austin C. Schultz and Les A. Edye, Sugar Research Institute, Australia
Molasses exhaustion is not the point from which no more sugar can be crystallized, but rather the point from which no more appreciable amounts of sugar can be economically recovered. Sucrose solubility is an equilibrium phenomenon while molasses exhaustion is a kinetic phenomenon. The complex interactions of sucrose, impurities and water that affect sucrose solubility and molasses exhaustion are examined using nuclear magnetic resonance (NMR) techniques. The development of an on-line device for the measurement of crystal content (CC) of massecuites using low resolution NMR instrumentation and the continuous monitoring of CC in a pilot vacuum pan are reported. Cross polarisation solid state NMR experiments on impurity sucrose mixtures provide information on the interaction of solutes and their competition for solvation by the limited available water.
#779 ASSESSING THE ROLE OF POLYPHENOLOXIDASE IN EXTRACT OXIDATION DARKENING
Susan S. Martin, USDA-ARS, Crops Research Laboratory, U.S.A.
A diode array spectrophotometer capable of recording at intervals a sample's detailed absorbance spectrum through the ultraviolet and visible range can be used to advantage in assessing the nature of extract oxidative darkening. Computer computation of difference spectra (the difference between spectra obtained at any two selected times) allows insight into the chemical processes underlying the oxidative reactions. As an example, a sugarbeet root extract was prepared from tissue that was frozen on dry ice and then extracted with ice-cold, nitrogen purged water. The ice-cold extract was rapidly transferred to the spectrophotometer cuvet and allowed to oxidize for 3 hr at room temperature, recording detailed absorbance spectra (200-800 nm) at five minute intervals. The importance of polyphenoloxidase (PPO) in oxidative darkening of the extract was confirmed by the appearance of dopachrome ( AMAX 305, 476 nm) recognizable through difference spectra although not evident in an individual absorbance spectrum because of the extract's strong general absorbance through the UV-visible range. The time-course of the reaction of a crude PPO preparation with tyrosine was compared for production of dopachrome and melanin pigments. PPO catalyzes the oxidation of tyrosine (3-hydroxphenylalanine) to 3,4-dihydroxphenylalanine (DOPA), and of DOPA to DOPA-quinone. Subsequent non-enzymatic reactions lead to the formation of dopachrome and to dark melanin pigments. Of several potential inhibitors of PPO activity, sulfhydryl compounds were most inhibitory. With consideration of the toxicity and handling requirements of sulfhydryl compounds, they can be useful for special clarification problems where normal clarificants do not function effectively.
#780 POLARISATION OF RAW SUGAR WITHOUT BASIC LEAD ACETATE: INTERNATIONAL COLLABORATIVE TEST
M. R. Player, G. S. Rowe, R. M. Urquhart, K. A. McCunnie, and D. McCarthy, CSR Central Laboratory, Australia
With the determination of the 100 degree point and the rotatory dispersion of quartz at near infrared (NIR) wavelengths reported at ICUMSA's 22nd Session at Berlin in 1998, it became possible to properly specify an alternative polarisation method for raw sugar that uses NIR wavelengths and does not require the use of a basic lead acetate clarifying agent.
On instructions from ICUMSA's Referee for Raw Sugar, Mr. Ross Urquhart, Central Laboratory, drafted an ICUMSA Method for polarisation using as a basis the method already in use by the US sugar industry. This draft method was then subjected to a collaborative test conducted among ten participating laboratories drawn from seven countries according to internationally accepted IUPAC protocols. The r and R values of 0.16 degrees Z and 0.27 degrees Z compare reasonably with those for the "wet lead" method whose r and R values of 0.10 degrees Z and 0.24 degrees Z were established in a comparable test.
#781 A NEW CLARIFYING REAGENT FOR POLARIZATION ANALYSIS OF SUGAR SOLUTIONS
Da-Wei Gao and Chung Chi Chou, Sugar Processing Research Institute, Inc.,U.S.A.
The XYZ clarifier for Pol analysis is a new reagent consisting mainly of the DEAE-Cellulose/bagasse, which is patented. Comparing with other clarifiers such as wet lead and aluminum-containing clarifiers, XYZ clarifier possesses following properties demonstrated by hundred of tests in SPRI's labs.
#782 AL KHALEEJ SUGAR - A WATER EFFICIENT REFINERY
Jamal Al Ghurair and G. C. Singh, Al Khaleej Sugar Co. LLC, U.A.E.
The Al Khaleej Sugar (AKS) refinery, located at the Jebel Ali Port of Dubai, United Arab Emirates, was designed in 1992-94, and commissioned in 1995, the refinery has been operating at its design capacity of 100 tonnes of melt per hour since November, 1997. Refinery is located in Middle East/Gulf, where water is a costly item ($l.8 per Cu. Mt). Because of high cost of water in this part of the world, it was desired that process technology at AKS would be such that it should have lower water consumption than established refineries which are operating at water usage level of 1 to 1.5 Cu. Mt. of fresh water per tonne of melt.
At AKS we have achieved fresh water consumption of 0.2 Cu. Mt./per tonne of melt. This paper reviews the plant and process arrangements to achieve above
The above information may be useful to solve contamination of condensing water in order to comply with environmental requirement and where fresh water is scarse or costly like in case of AKS.
#783 ERP'S IN THE SUGAR INDUSTRY - CENTRAL EL PALMAR BUSINESS MODEL
Juan J. Mendoza, Central El Palmar, SA; Gabriela Moreno, Grupo Palmar, Venezuela
The purpose of this paper is to describe the implementation process of an ERP (Enterprise Resource Planning) software, conducted at Central El Palmar and other companies of the Grupo Palmar, using inside personnel.
The case includes most aspects of the project, starting with the design of individual ideal business models for each company to their actual deployment. Although the models are referred to industries such as swine genetics and production farms, cattle feed plant, meat processing, fiber board manufacturing from sugar cane bagasse and sugar cane production, emphasis is made on the sugar production model.
The models serve as guidelines for the adaptation of past practices to new worldclass business procedures. Integration of data and processes is the key factor in the pursuit of relevant, timely and complete information needed to run these businesses. Along with the integration of logistics, manufacturing and distribution processes with the finance module, a great deal of control features and planning tools are gained. Such advantages would be very difficult to obtain without the help of an ERP system.
Another important part of the paper is related to the implementation of the software using inside personnel. The team of people involved in the process is mainly composed of members of all business areas of the companies other than the Information Technology department, which in this case plays a support role.
Some important concepts are explained for the purpose of understanding this paper, such as Business Models, Competence Center, Reference Models, Key Users and Final Users, among others.
The ERP software implemented is Baan IV C2, however the software evaluation phase of the project is not a part of this paper.
#784 REVIEW OF MODERN TYPES OF SILOS FOR WHITE SUGAR
Hansjoachim Wunsch, IPRO Industrieprojekt GmbH, Germany
Various types of silos for white sugar commonly in use will be presented, i.e. cylindric reinforced concrete silos, cylindric steel silos, dome silos as well as horizontal warehouses. These silo types have been erected worldwide up to a capacity of 100,000 t each.
The technological aspects of an optimal white sugar storage will be shown and the type of silos will be presented critically regarding
The above systems and the costs will be compared on basis of a 50,000 t white sugar silo.
Furthermore, specific prices per m3 stored sugar and the investment costs in relation to the size of the silos will be shown.
The presentation will be closed with a report on the present status of two 80,000 t reinforced concrete silos under construction for the German sugar industry.
#785 DIVERSIFICATION PROGRAM AT TAIWAN SUGAR CORPORATION
Chien-nan Chiu, Taiwan Sugar Corporation, Republic of China
Due to rapid economic development, the sugar industry in Taiwan has been on the decline year by year. In the 1960s, Taiwan Sugar Corporation (TSC) only produced sugar and its by-products such as alcohol and yeast powder by using molasses, hard/soft pressed board and bagasse pulp by using bagasse. TSC started raising hogs and developing feed business, which further brought about the manufacture of such by-products as soybean oil and soybean meal. After many years of development, TSC has become an extensively diversified agricultural and industrial enterprise. With the impact of Taiwan's entry into the World Trade Organization in the near future and a tendency towards liberalization and privatization, TSC has also diversified its production into many other fields. For example, to put its abundant land and manpower resources to the best use, TSC has given priority to land development and construction business.
Biotechnology is also a target of investment for TSC. By applying biotechnology to quality agriculture, TSC is able to cultivate high-value-added plants like phaelopnosis. The other biotechnological products produced by TSC include health foods (such as Ling Zhi and Cordyceps sinensis Mycelia), biopesticide, biochemical medicine, and organic fertilizer.
In addition to the above-mentioned businesses, TSC has also been seeking opportunities for reinvestments and joint ventures in the fields of biotechnology and high technology.
In view of the limitations imposed on the development of sugar and animal industry in Taiwan, TSC has decided to make investment in foreign countries, such as Vietnam, Australia, Canada, the United States and Cost Rica. Of the various sugar operations, refinery is the only one TSC will continue with in the future. Because of TSC's diversification into other lines, it is expected that the revenues from sugar business will scale down to less than 13%.
#786 RECENT DEVELOPMENTS AND APPLICATIONS OF IN-LINE COLOUR MEASUREMENT OF CRYSTALLINE SUGAR
Bjarne Chr. Nielsen, Neltec, Denmark
Cost-effective operation of centrifugals requires frequent monitoring of the centrifugal performance. In order to optimise the separation process without sacrificing the quality many beet factories and refineries have installed Neltec ColourQ in-line instruments for continuous colour measurement. The instruments are calibrated to ICUMSA colour in solution and have a good accuracy. Compared to the lab results, the instruments do not add any significant error. The range of colours measured at different installations is from below l0 ICU up to 4000 ICU. Some recent developments and installations are presented.
#787 EXPERIENCES WITH NEW BATCH CENTRIFUGAL CONCEPT
Reinhold Hempelmann, Uwe Schwanke, BMA, Germany
In order to increase the performance of batch centrifugals, to facilitate and simplify their installation and operation and to reduce maintenance requirements, the design of the complete batch centrifugal concept is continuously subjected to a modernization and improvement process.
With regard to high performance, the maximum massecuite throughput per hour is determined by two main influencing factors:
The massecuite capacity is given by the basket volume plus the prepurging effect during filling, which is limited by the flow resistance in the sugar layer. For higher throughputs the cycle time can be reduced specifically in the braking and discharging phases. Experience with the novel large discharger plough have shown, that a faster discharge process does not require different peripheral devices.
The combination of a modern IGBT frequency converter with energy recovery system and an asynchronous motor will reduce braking times with a full basket by at least 10 secs.
The influence of these effects on the cycle characteristics will be shown in detail.
BMA developed it's own innovative control system consisting of an industrial computer incorporated in the control panel and the software.
#788 CHARACTERISATION OF COLORANTS IN SUGAR INDUSTRY
Amel Mersad, Richard Lewandowski, Martine Decloux, Ecole Nationale des Industries Alimentaires, France
Colorants are among the most troublesome impurities in the production of white cane sugar. They are present in the juices from the milling step and are incrusted in the crystal, decreasing its purity. Despite the diversity of colorants in sugar solutions, presently, coloration is assessed by measuring absorbency at 420 nm.
A bibliographic survey of different types of colorants is carried out, in order to characterize them individually. Their origin, as well as the chemical reactions and the conditions resulting in their formation are emphasized. It turns out that natural colorants originating from sugar cane (chlorophylls, xanthophylls, carotene, flavonoids …) and melanins, which are produced during sugar processing, absorb in visible light. However, most other colorants (Caramels, Melanoidins and HADP), absorb in ultraviolet. The latter colorants are nevertheless very problematic because they are constantly formed throughout all stages of sugar processing.
In order to confirm these findings, Caramel colorant was synthesized and analyzed by spectrophotometry. The absorbency of this colorant at 420 nm was found to be negligible compared to its absorbency at some other wavelengths in the UV. The maximum value was at 285 nm. In the visible spectrum, absorbencies were significantly increased when the pH was increased from 4 to 7 then to 9. The indicator value, which evaluates the influence of the pH value on the absorbency at 420 nm, is defined to be the ratio IV = abs at 420 nm and pH9/ abs at 420 nm and pH4. It was l.76 for Caramel. This value is slightly greater than the values ranging from 1 to 1.5 found by Godshall (l997). On the other hand, the UV spectra (190-325 nm) at pH 4, 7 and 9 were nearly superimposed. It appears therefore that pH has extremely limited influence over the absorbency of Caramel at its wavelength of maximal absorbency (285 nm). Melanins and HADP remain under study.