Drying of Curcuma (Curcuma xanthorrhiza roxb) Using Double Plate Collector Solar Dryer

Abstract

Curcuma (Curcuma xanthorrhiza roxb) currently used as traditional medicine and as a dye. If the Curcuma will be saved then the water content should not be more than 10-11%. The advantages of drying using a glass plate covered with double collector type can reduce the water content below 10-11 %, reduced drying time and produce dust-free product. The experiment is carried out by inserting curcuma that has been in the form of thin slices into the dryer. Dryers are equipped with several sensors those are (temperature, relative humidity, weight scale and the intensity of sun light) sensors. Measurements of those parameters are performed every interval of 5 minutes. The intensity of sunlight during the day it changes that followed by changes of relative humidity of air (RH) and the rate of water evaporation. Effect of RH, the intensity and temperature in the dryer to the drying characteristic is correlated using mathematical model. There are three common mathematical models used in this experiment as well as the Newton, Page's and Pabis and Page modified equation for calculate the (Specific Moisture Evaporation Rate, SMER) and dryer’s performance is expressed by this parameter. The SMER on the 10th of June 2012 reached 0,588 kg/KWh. From these data could be concluded that the effectiveness of the dryer is very good for use as a drying of agricultural products such as curcuma. The equation of this process is modification temperature page equation as MR = exp(0.004.T0.468.t1.3615) with the RMSE was 2.2 %.