Development of inclined plate honey moisture reduction system.

Honey is delicious, nutritious and has high medicinal value in comparison to other sweeteners. Honey is usually extracted from comb as immature product which results in high moisture which makes it more liable to be fermented by osmophilic yeasts. So, it needs to be processed for moisture reduction, to delay crystallization and to overcome the problem of fermentation. In the present investigation, a honey moisture reduction system was developed and tested to reduce the moisture content of honey to about 17%. The system consisted of a flat plate inclined at an angle. The plate was heated from the underside and honey for moisture reduction was re-circulated over it until desired moisture content was achieved. Experiments were conducted for honey moisture reduction at water temperature of 40-70 °C with plate inclinations of 30°-60° according to four level full factorial design of experiment. The results showed that the total reduction time required for reaching moisture content of about 17% varied with water temperature and angle of inclination. The moisture reduction time required for reaching a moisture content of 17 percent at 40 °C was about five times the time required at 70 °C. The energy cost of honey moisture content reduction from 21.5 to 17% was Rs. 4.7 to Rs. 12.5 per kg.

Honey moisture reduction and its quality.

Beekeeping has been widely promoted in many countries as a major contributor to rural development. Honey is a sweet and viscous liquid which has sweetness due to the presence of monosaccharides. The major constituents of honey are sugars, water, proteins, enzymes, acids and minerals, while the major causes of quality deterioration include heating at high temperatures, high moisture content, adulteration, poor packaging and poor storage conditions. Heating not only eases the processing of bottling by reducing the viscosity of honey, but also reduces the water content in honey to prevent fermentation and delays the granulation by destroying large sugar nuclei. The paper discusses about the different honey moisture reduction systems designed by research workers as well as beekeepers at farm level and the different quality parameters affected by thermal treatment of honey.

Thermal drying of industrial sludge using forced aeration.

This study investigated an industrial biosludge drying system using hot gases from a coal furnace, seeking to increase the solids content of the biosludge above 50% (w.b.), considered suitable for combustion in biomass boilers. Biosludge was collected from a paper mill activated sludge plant. Biosludge mixtures with eucalyptus chips and eucalyptus bark in two different proportions (15% and 25%) were placed into a drying chamber. Hot gases generated by the furnace, with a flowrate of 0.64 ± 0.02 m3 s-1 at 100 ± 20°C, were applied to the piles through a blowing system. The results demonstrated that the 75% biosludge/25% eucalyptus bark mixture achieved the best drying ratio, increasing the total solids content from 31% to 72%, over a 5-h drying period. Nevertheless, all other treatments involving the addition of a bulking agent achieved solids content above 50%, confirming the positive effect of adding dried material to the sludge. These results indicate a potential use of hot gases that are currently available and released into the atmosphere by paper mills.