REDESAIN DAN UJI EXPERIMENTAL PENGERING BIJI KAKAO SISTIM KONTINYU

Abstrak

The present study aims to redesign and test a prototype of a continuous cocoa bean dryer that incorporates the type oftray dryer and screw dryer in a drying system. Redesign is aimed to improve the performance of drying machines interms of product quality that meets Indonesia National Standard (SNI) specifications for export requirements of cocoabeans. The research includes design modification and experimental test of the continuous dryer machine. Modificationshave been carried out primarily to motor drive types with additional rotary controls, hot gas conduits, thermal insulators,and screw shafts. The capacity of the engine product produces an average of 60 kg/ hour. The parameters monitored andcontrolled are the temperature of the hot gas, the temperature of the dryer room medium, the motor shaft rotation, therotation of the screw shaft, the mass flow rate of the cocoa beans and the moisture content. The experimental tests showthat machine capacity can be increased up to (72 kg/hr), the percentage of broken cocoa beans on average 8% (50%before redesigned), the percentage of decreasing water content of 10.9% (average 4% before redesigned), and cocoabeans moisture content yield level 7% can be achieved in 4 cycles (9 % before redesigned). In addition, energy usageefficiency increases from 20% (before) to 42.3% (after redesigned).