Progressive Freeze Concentration of Coconut Water: Effect of Coolant Temperature on Process Efficiency and Heat Transfer

Abstract:

In this research, coconut water was concentrated by applying progressive freeze concentration (PFC) using coil crystallizer. Overall heat transfer coefficient (U) was analyzed from the process by varying different coolant temperature values since both of them are closely related. In this case, heat transfer efficiency depends strongly on ice crystal formed on the inner cooled surface and is explained theoretically from that angle. At optimum flowrate, operation time and initial concentration best results were observed at-10oC of coolant temperature where the concentration efficiency and effective partition constant (K) obtained were 48% and 0.2 respectively. Meanwhile, U obtained at the first and second stages were 183.0046 W/m2oC but dropped at lower value at later stage at 154.9625 W/m2oC due to ice fouling.

• Periodical: Applied Mechanics and Materials (Volume 695)
• Pages: 447-450
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.695.447
• Online since: November 2014
• Authors: Safiei Nor Zanariah, Mohamed Nor Noor Naimah, Norzita Ngadi, Zaki Yamani Zakaria, Jusoh Mazura*
• Keywords: Coconut Water, Concentration Efficiency, Effective Partition Constant, Overall Heat Transfer Coefficient, Progressive Freeze Concentration

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