Experimental behaviour of a three-stage metal hydride hydrogen compressor

TL;DR

This paper presents an experimental study of a three-stage metal hydride hydrogen compressor using AB2 alloys, demonstrating high compression ratios and effective thermal management across a wide pressure and temperature range.

Contribution

It introduces a novel three-stage MHHC system with optimized thermal management and reports experimental performance data including high compression ratios.

Findings

Achieved a compression ratio of 84.7 at 122 bar outlet pressure.

Operates effectively from vacuum to 250 bar and RT to 200°C.

Demonstrated efficient thermal management during hydrogen absorption/desorption.

Abstract

A three-stage metal hydride hydrogen compressor (MHHC) system based in AB2-type alloys has been set-up. Every stage can be considered as a Sieverts-type apparatus. The MHHC system can work in the pressure and temperature ranges comprised from vacuum to 250 bar and from RT to 200C, respectively. An efficient thermal management system was set up for the operational ranges of temperature designed. It dumps temperature shifts due to hydrogen expansion during stage coupling and hydrogen absorption/desorption in the alloys. Each reactor consists of a single and thin stainless-steel tube to maximize heat transfer. They are filled with similar amount of AB2 alloy. The MHHC system was able to produce a compression ratio (CR) as high as of 84.7 for inlet and outlet hydrogen pressures of 1.44 and 122 bar for a temperature span of 23 to 120C.