Modifikasi Penukar Panas Model Pengering Hybrid Tipe Rak untuk Pengeringan Chip Mocaf

Abstract

The main problems of previous experiment using rack type greenhouse effect dryer (GHE) equipment were low level of drying efficiency and high level of energy consumption, therefore the purposes of this experiment were to develop the design of heat exchanger and biomass stove from rack type GHE dryer and to develop the performance of hybrid rack type GHE dryer for drying mocaf chips. One of the developments of the design was the addition of circle type fins on heat exchanger as much as 9 fins per pipe. The dimension of each fin was 0.093 m x 0.063 m. Materials of the stove were bricks by dimension of 0.58 m x 0.58 m x 0.3 m (L x W x H). The drying experiment during daylight period using mocaf chips with capacity of 18.04 kg from moisture content of 69.88%db to 12.56%db needed 11.5 hours with drying temperature of 43.65C. The drying efficiency was 9.37%, thermal efficiency was 24.84% and specific energy consumption was 28.19 MJ/kg vapor. In the experiment capacity of 18.09 kg mocaf chips during daylight and night period from moisture content of 70.74%db to 13.76%db required drying time of 15 hours with drying temperature of 45.83C, drying efficiency was 6.79%, thermal efficiensy was 24.32%, and specific energy consumption was 32.80 MJ/kg vapor. This research resulted increased efficiency of 1.697% than previous design.