The Effect of Initial Moisture Content on Moisture Migration in a Big Bag of Sugar in the Presence of Cyclic Temperature Changes: Numerical Analysis

The study of moisture migration in a big bag of sugar in which undergoes the fluctuation of temperature as in the shipping condition was investigated by a mathematical model. The mathematical model was derived from the conservation of mass and energy, solved by numerical method of lines, validated with the experimental data reported in the previous literature, and used to predict moisture migration for 30 days. It has revealed that the initial moisture content before shipping has the significant effect on the moisture migration. It was found that the large amount of moisture diffuses into the interfacial big bag along and the periodical adsorption and desorption takes place when the initial moisture content is high; hence, caking of moist sugar is likely to occur. The result greatly yields useful information for studying caking formation due to moisture migration

Modelling and Feedforward Control of Pulsed Bed Adsorption Column for Colorant Removal in Sugar Syrup

In sugar refining, pulsed bed adsorption columns are used to remove colorants in sugar syrup. The pulsed bed adsorption column is a cyclic steady state operation that maximize the adsorbent utilization due to the increased driving force but requires special attention on control and optimization. The modelling and feedforward control of the pulsed bed adsorption columns is investigated in this article. The aim of this research is to develop the mathematical model of pulsed bed adsorption column by using the parameters obtained from breakthrough of fixed bed column and to investigate the optimum cycle time at different colorant concentrations in feed sugar syrup. The analysis showed that the optimum cycle time of pulsed bed adsorption column depended on feed flow rates and the colorant concentrations in feed sugar syrup. As the feed flow rate and colorant concentration increased, the optimum cycle time decreased. The feedforward control successfully compensated the effects of disturbances from colorant concentrations in feed syrup for both step and cosine functions and yielded the sugar syrup that met its specification

Agricultural residue gasification for low-cost, low-carbon decentralized power:An empirical case study in Cambodia

Abstract not availableJohn L. Field, Paul Tanger, Simon J. Shackley, Stephan M. Haefel

Numerical Modeling of Industrial-Scale Pulsed Bed Adsorber for Colorant Removal in Sugar Refining

Because pulsed bed adsorbers are preferred when the high fluid flow rate is expected, pulsed bed adsorbers are used in many industries; for example, waste water treatment and food industries. However, few attempts have been focused on modeling of pulsed bed adsorbers. In this paper, the mathematical model of an industrial-scale pulsed bed adsorber has been developed. By using the data on adsorption equilibrium constant, mass transfer and axial dispersion in a lab-scaled fixed-bed adsorber, the numerical analysis of an industrial-scale pulsed bed adsorber for colorant removal in sugar refining process is performed and the numerical results are analyzed to gain the better understanding of this unit operation. The optimum cycle time depended on the fraction of adsorbent being removed and replaced in each pulse; the optimum cycle time increases from 4 hours at 5 % pulse to 12 hours at 14% pulse. In addition, the fluctuation of feed flow rate would affect the performance of pulsed bed adsorbers; for example, the 10% increase of flow rate would make the colorant in the syrup at the outlet higher than its specification. The finding of this paper would allow engineers to optimize an industrial-scale pulsed bed adsorber more efficiently.</jats:p

Gradient formation in membrane unit for differential precipitation of proteins

ผลงานวิชาการคณาจารย์มหาวิทยาลัยเทคโนโลยีสุรนาร