Performance Evaluation of Absorbent Materials in Evaporative Cooling System for the Storage of Fruits and Vegetables

Abstract

An experimental storage based on the principle of evaporative cooling was designed to evaluate the performance of three natural absorbent fiber materials to be used as cooling pads. The absorbent materials were jute, hessian and cotton waste. The performance criteria included cooling efficiency, material performance and total amount of heat load removed from the evaporative cooler. The results showed that under the no-load condition, the average cooling efficiency was highest for jute at 86.2%, compared to 76.3% for cotton waste and 61.7% for hessian fiber. Materials performance tests results showed that the highest resistance to mold formation was exhibited by hessian followed by cotton waste, while the jute fiber had very poor performance. The heat load determination also showed that products stored in the cooler with jute as water absorbent produced the least heat of respiration, followed by cotton waste and hessian in that order. The total results indicated that jute had the overall advantage over the other materials. However, if the cotton waste surface could be modified to offer larger surface required for evaporation, it would be the best alternative because the jute surface is prone to mold formation.

Evaluation of Pads and Geometrical Shapes for Constructing Evaporative Cooling System

“…Therefore, for a given size of cooler, lighter bulk weight would be handled the lesser the bulk density of the cooling pad. Olosunde et al (2009) used jute pad that was less dense (82.81 kg/kg) than the type used in this study (89.80 kg/kg) also whose water holding capacity was lower (1.762 kg/kg) than the type in this study (2.1 kg/kg) .…”

“…Al-Sulaiman (2002) reported cooling efficiency of 62.1% with jute pad, 55.1, 49.5 and 38.9% with luffa, Aspen wood excelsior and palm fibers, respectively. Olosunde et al (2009) reported 86.2% cooling efficiency for jute pad. Gunhan et al (2007) reported a range of cooling efficiency for five different pads under different conditions: CELdek (46.1 to 78.5%); Volcanic tuff (68.0 to 77.9%); Fine pumice stones (77.7 to 90.6%), coarse pumice stones (56.1 to 72.1%); shading net (25.2 to 32.8%).…”

“…Hanan et al (1978) reported that the pad and fan method of cooling green houses revolutionized the industry. Many other researchers have experimented on different pad materials such as successive layers of corrugated paper (Koca et al, 1991), natural fibers-jute, palm, luffa (Al-Sulaiman, 2002), corrugated cellulose (Lertsatitthanakorn et al, 2006), pumice stones-coarse and fine (Gunhan et al, 2007), jute, hessian and cotton waste (Olosunde et al, 2009), rice straw and palm leaf fibers (Darwesh et al, 2009), Celdek R 7060-15, Munters AB, Kista, Sweden (Dagtekin et al, 2009, clay (Ndukwu, 2011), straw, CELdek, sliced wood (Ahmed et al, 2011), metal pad, cellulose pad, organic pad (CELdek), inorganic pad (GLASdek), PVC pad, porous ceramic pad, wood wool pad (Xuan et al, 2012). This study was therefore undertaken to investigate and evaluate the effectiveness of potential cooling pads (using locally available materials) and shapes for constructing evaporative cooling systems.…”

Evaluation of a new heat transfer and evaporative design for a zero energy storage structure

“…In this context, some methods of preserving fruit http://dx.doi.org/10.1016/j.solener.2015.06.006 0038-092X/Ó 2015 Elsevier Ltd. All rights reserved. and vegetables, other than expensive electric powered refrigeration systems, such as storage in a ventilated shed, using zero energy storage based on an evaporative coolant system, waxing and hot water treatment have been found to be an efficient and economical means of reducing postharvest storage loss worldwide (Couey, 1989;Fallik et al, 1996;Olosunde, 2006;Lu et al, 2007;Sushmita et al, 2008;Islam and Morimoto, 2012). According to Dvizama (2010), the shelf life of fruit and vegetables is enhanced by minimizing deteriorative reactions, and availability for longer periods would reduce fluctuations in market supply and prices.…”

Progress and development in brick wall cooler storage system

“…In this contest some methods of preservation of fruit and vegetables alternative to electric powered expensive refrigeration system like storage in ventilated shed, use of zero energy storage based on evaporative coolant system, waxing and hot water treatment has been found to be an efficient and economical means of reducing postharvest storage loss worldwide [7][8][9][10][11][12]. According to Dvizama [13], shelf life of fruit and vegetables are enhanced by minimizing deteriorative reactions and availability for longer periods would reduce fluctuation in market supply and prices.…”