Mass Transfer of a Small-Medium Enterprise (SME) Size Pineapple Juice Extractor

Abstract

The compact reversing counter current extractor (RCCE) for pineapple juice from its peel was designed and developed. Consequently, the extraction trail with the RCCE were studied using diff'erent three variables, namely draft, retention time and extraction temperature. The equilibrium distribution and diffusion coefficients of solute in solid phase in the batch extractor were estimated. The results show that at draft value of 2, retention time of go min and extraction temperature of zo" C provided a maximum percentage yield of zo.g. In the steady state, a solute concentration profile in solid and liquid phases at any point throughout this extractor had the same pattern as fhe other states. In addition, the mathematical  cliffusion-back-mixing model was simulated to describe kinetic of mass tratrsfer in various conditions. The simulated data by diffusion-back-mixing model hacl good agreernent with the experimental data rn the solid phase whilst the simulated data showed the same trend as the experimental data in the liqurd phase. The results showed that the back-mixing proccss caused increasing of mass transfer of solutes on the solid surface area. This is conesponded to the reduction in driving force due to its resistance to mass transfer. The differences between experimental and predicted results are highly related to the variation of Biot number and Peclet number.