A Microprocessor Control System for Peanut Drying¹

A microprocessor based peanut dryer control system to minimize energy consumption was developed and tested over a 3 year period. Hardware and software needs were described. First year tests were conducted to verify hardware performance. Energy control techniques were proposed and compared with conventional peanut dryer control procedures. In simultaneous comparative tests, the first energy control technique implemented reduced liquified petroleum gas (LPG) consumption 49 percent, electric energy 39 percent and increased time on the dryer 65 percent. Modification of the energy control technique reduced the unacceptable increase in time on the dryer to 10–20 percent while similar reductions in LPG and electric energy were maintained. The improved control technique produced similar results in tests the following year. No losses in peanut quality during drying were observed and the net saving was $5.61 per tonne or a 25 percent reduction in peanut drying costs for Virginia conditions.