The Sixth International Hydrogen Technologies Congress (IHTEC-2022), Çanakkale, Turkey, 23 - 26 January 2022, pp.52-54
In this study, a waste heat recovery system for a cement plant is presented and analyzed with Aspen Plus software.
The presented system has a steam Rankine cycle combined with an organic Rankine cycle, an alkaline electrolyzer
unit, oxygen and hydrogen storage tanks, a blending unit, and a combustor. Moreover, multiple useful outputs are
obtained such as power, hydrogen, and natural gas, and hydrogen blend. Power obtained from the organic Rankine
cycle has the highest value when R600a is used as a working fluid. Generated power from turbines is fed to the
grid and also utilized to produce hydrogen via an alkaline electrolyzer which has an efficiency of 62.94%. With the
change of the percentage of hydrogen in the blend from 0% to 50%, the annual consumption of natural gas reduces
from 48.261 billion m3 to 37.086 billion m3. Also, carbon dioxide emissions decrease from 0.04 mol/s to 0.032 mol/s
at the syngas stream with 20% hydrogen addition by volume.