Design of a liquid organic hydrogen carrier (LOHC) dehydrogenation system integrated with the concentrated solar power (CSP) plant

Abstract

The present study combines the perhydro dibenzyl toluene (PDBT) dehydrogenation reactor with the heat supplied by the heat transfer fluid, namely diphenyl ether (DPE), from the concentrated solar power (CSP) plant. The flowsheet has been simulated using the combination of DWSim v 6.5.2 and Python.NET. The dehydrogenation reactor is operated at a feed temperature between 563 K and 633 K and a pressure of 2 atm. The diphenyl ether is supplied to heat the reactor at the inlet temperature of the thermic fluid to the jacket at 663 K and 673 K. The process has been simulated to produce 10 Nm3/hr of industrial-grade hydrogen. The variation of the feed temperature, the temperature of the thermic fluid in the jacket and PDBT conversion across the catalyst weight with respect to the inlet feed temperature, the inlet temperature of the thermic fluid to the jacket and flow direction (co-current and counter-current) in the jacketed packed bed reactor (PBR) has been studied. Similarly, the weight of the catalyst required for the reactor, the area needed for the heat exchangers, and the concentrated solar power (CSP) plant have also been discussed. Cost analysis of the catalyst, concentrated solar power plant, the total annual cost of the process and the cost per kilogram of hydrogen based on the inlet feed temperature, the inlet temperature of the thermic fluid to the jacket, and the direction of the flow in the jacketed PBR have been considered. The lowest total annual cost of the process is found at the counter-current mode of operation, with the inlet feed temperature of 623 K and the inlet temperature of the thermic fluid to the jacket at 673 K.