Optimization of Operation Parameters of a Vertical Sterilizer of Medium-Scale Oil Palm Mill Using Taguchi Method

In this study optimum operation parameters of a newly developed sterilizer of the medium-scale oil palm processing mill were investigated for maximum oil yield. Taguchi's experimental design of orthogonal array L9 ( 34) was adopted to generate nine runs of experiment. Response surface method was used to optimize operation parameters and validated using Taguchi's table. However, experimental result was analyzed to generate predicted-dependent operation parameters through linear multiple regression equations. Hence, coefficients of correlations were established using Karl Persons's formula. The optimum predicted indepenent operation parameters for the sterilizer were Tenera 33.33 years, 128.89 degrees C, 3 bar, 51.11 min for age of Tenera fruits, initial temperature, pressure of superheated steam, and sterilization period, respectively. These optimum values correspond to 6th run on Taguchi's table. The coefficients of correlations between experimental and predicted values were: 0.87, 0.85, 0.99, and 0.54 for equilibrium temperature, equilibrium pressure, oil yield, and efficiency, respectively. Practical ApplicationsThe indigenous technology of oil palm processing in Nigeria has not been developed beyond small-scale method, which is characterized with unscientific techniques and facility. In this small-scale method oil palm fruits are sterilized using unpressurize vessel without instrumentation and control devices for parameters regulation and monitoring. Because of the poor economy in Africa and Nigeria in particular, large-scale mill remain unaffordable. Hence to enhance productivity of oil palm, a vertical sterilizer was developed as one of the unit operations of a synchronized medium-scale oil palm fruit processing mill. In this synchronized mill, fresh oil palm fruits were sterilized using developed sterilizer (pressure vessel) that was coupled with fire-in-tube boiler. For the effective handling of this facility, investigation of the optimum operation parameters of the sterilizer such as: age of Tenera fruits, superheated steam temperature and pressure, likewise sterilization period is essential to enhance oil yield, hence this study.