Thermodynamic analysis and experimental study of solid/gas reactor operating in open mode

Multi-physical continuum models of thermochemical heat storage and transformation in porous media and powder beds—A review

“…That allows for the numerical screening of materials on the reactor level based on simplified kinetic expressions if the overall reactor performance is the main subject of interest. The study further confirmed an ''operating line" concept introduced by Marias et al [47] for periods in which the reactor is operating in a quasisteady state. For cyclic operations, a local time-integral conversion degree was introduced measuring spatial differences in the number and completeness of conversion cycles experienced by the solid material.…”

“…Typically, these models lack spatial resolution assuming the reactor or entire system components as homogeneous control volumes with an internally uniform state and allow the study of optimal control, predimensioning or sizing of a complete unit including exergetic considerations, e.g., [4,11,20,21,27,31,[37][38][39][40][41][42][43][44][45][46][47][48][49]. Such models are computationally cheap and allow a rough dimensioning of reactors or the simulation of their behaviour as part of larger systems, but lack the features required for a detailed modelling of processes occurring inside the reactor, for capturing heterogeneities within the reactive bed, or for detailed reactor design.…”

The influence of gas–solid reaction kinetics in models of thermochemical heat storage under monotonic and cyclic loading

“…where w ¼ q V =q N is a relative humidity measure that can be converted to the mass fractions used in the present study via The exact position on the line depends on kinetics, conversion, heat transfer, mass diffusion and others [28]. The concept was validated experimentally for a strontium bromide and aluminium potassium sulphate hydration.…”

“…Marias et al [28] introduced a charge/discharge operating line that allows the estimation of outlet conditions based on inlet conditions (temperature and humidity) in an open mode thermochemical reactor. Based on the assumptions that temperature variations are weak and thermal equilibrium is adhered to, the outlet conditions lie somewhere on the operating line given by (adapted to our system)…”

“…In order to test the validity of the operation lines for the present simulations, we plotted the outlet gas state in psychometric plots together with the van't Hoff equilibrium line and the operating line as done in [28] both for monotonic and cyclic loading (Fig. 11).…”