Evaluating the Trade-Off Between Energy Efficiency and Energy Saving in Spray Drying Operations

Year 2025, Erken Görünüm, 1 - 1

Gülşah Karaca Dolgun

https://doi.org/10.29109/gujsc.1562960

Abstract

In this study, modelling simulations were employed to analyze the effects of inlet drying air flow rate and temperature, product feed rate, and heat recovery ratio in a spray dryer. The energy efficiency, energy savings, and final product outlet temperature were investigated. As the heat recovery ratio (by-pass ratio) increased, total energy savings improved, though energy efficiency declined at a slower rate compared to energy savings. The modelling study, conducted with five different by-pass ratios (100%, 70%, 50%, 30%, and 0%), indicated that the optimal by-pass ratio was 30%. At this ratio, energy efficiency decreased by 5%, while energy savings increased by approximately 16%. Additionally, at higher by-pass ratios, the product outlet temperature rose significantly. To maintain product quality, it was found that the maximum acceptable temperature of 60°C could be achieved at by-pass ratios of 40% or lower.

Keywords

Spray dryer, energy efficiency, energy saving, milk powder;

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