Drying model for “rambak” crackers production using hybrid greenhouse effect dryer with stove biomass and clay heat exchanger

A hybrid greenhouse effect dryer was examined for small-medium cracker industries. The system consists of a main drying chamber, biomass stove, heat exchanger, and shelf. This work aims to construct heat and mass transfer model which can describe well the drying process, as well as can be used to predict the greenhouse air temperature, product temperature, and moisture evaporation during drying. Drying is conducted in the room dryer for 9 samples of crackers where each sample is ± 150 grams and is divided into 3 samples placed on the bottom shelf, 3 samples on middle shelf, and 3 samples on the top shelf. Drying is carried out from the initial moisture content of crackers ± 63-64 to 12-14 for the standard fries. Mathematics model was simulated in MATLAB software and was validated by comparing the analytical and experimental result. The heat transfer model could describe well the heat transfer process during drying. It was shown that the analytical and experimental results are in good agreement, with mean error range values 5.38-20.4. © 2020 Trans Tech Publications Ltd, Switzerland.