Evaluasi Hasil Rekayasa Pengering Tipe Bak Kayu Blower Ganda dengan Sumber Energi Gas LPG untuk Pengeringan Benih Kedelai pada Sistem Jabalsim

Abstract

Problem faced on continous soybean seed supplies based on location and seasons (the Jabalsim) system is that soybean crops are harvested during the rainy season. This has caused the seed quality does not meet the standard requirement set forth by the government. The purpose of this study was to evaluate the effectiveness of the flat bed dryer with an LPG energy source, for soybean seed drying. Research was conducted at the Laboratory of Agricultural Mechanization of the Indonesian Legumes and Tuber Crops Research Institute (ILETRI), in Malang and at Muneng Experiment Station, Probolinggo, East Java, from January to December 2010. The study included designing and performance evaluation of the dryer for its drying capacity and seed viability, and the analysis of financial benefit to the seed grower using the B/C ratio. The performance evaluation was done using soybean varieties Kaba and Grobogan. The results showed that drying process of both soybean varieties followed an exponential model with the coefficient of determinations (R2) was 0.94 to 0.99. Drying soybean seeds using the flat bed dryer using LPG as the energy source was faster than that using the drying floor. The drying rate of soybean seeds of Kaba variety using the flat bed dryer and using the drying floor was faster than those on variety Grobogan. It took 6 hours for drying 260 kg soybean seed with 20% moisture content wet basis (obtained from 1 ton of unthreshed soybean) into 11% wet basis, thus the drying capacity of the dryer was only 43 kg/hour. At an average rate of drying air temperature 45.5oC, the viability of the soybean seeds was 73 to 84%, still meet the standard seed quality of the government (minimum 70%). The cost benefit ratio (B/C ratio) was 1.12 when the price of the dryer is Rp 22 million/unit and the service charge for the soybean seed drying is Rp 2,600/kg seeds. Technically and financially, innovation of the flat bed dryer with an LPG energy source was still feasible to be applied by seed producers during the wet season, following the Jabalsim seed system.