Interpreting exergy analysis as applied to spray drying systems. (24th February 2020)

• Record Type: Journal Article
• Authors: Johnson, Perry William; Langrish, Timothy A.G.
• Is Part Of: International journal of exergy. Volume 31:Number 2(2020)
• Page Start: 120
• Page End: 149
• Publication Date: 2020-02-24
• Subjects: energy -- exergy -- analysis -- dryer -- vapour recompression -- optimisation; Exergy -- Periodicals; 621.402105
• Languages: English
• ISSNs: 1742-8297

Abstract

The comparison of different energy recovery systems employed on a spray dryer is challenging. This work compares two cases with a base case of a dryer alone, to identify any available improvements and interpretation of the factors used within exergy analysis, for system-wide optimisation. While exergy analysis results indicate natural gas boiler systems (case 1) are superior to compressor-driven recovery systems (case 2) (13% better evaporation efficiency), this paper demonstrates the significant potential to improve either system, and that dryers are one of the limiting units within the process (38% exergy improvement potential). The improvement potential for both cases is quite high (~90% of total added exergy), particularly as the inlet gas temperature increases. This paper demonstrates a method of simplifying exergy analysis to make it more accessible to engineers as a tool for optimising thermal and non-thermal systems that include a dryer as a significant part of the system.