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Sustainability metrics, a cradle-to-gate life cycle assessment, and a technoeconomic evaluation are presented for an optimized entrained-flow coal oxy-combustion plant with carbon capture to produc...

Living systems must continuously receive substrates from subenvironment, and the population metabolic rate model is affected on this flow of substrates to be metabolized, its relevant variables, and the rate at which operates. This study focuses on the influences of resistances and bulk phase factors with in the subenvironment and by thermodynamic coupling on reaction-transport processes representing a simple enzymatic conversion of a substrate to a product. Thermodynamic coupling refers to mass flow, or a reaction velocity that occurs without or opposite to the direction imposed by its primary thermodynamic driving force. We considered the effects of (i) subenvironment resistances for the heat and mass flows of reacting substrate in the form of the ratios of Sherwood to Nusselt numbers, (ii) the subenvironment bulk phase temperatures and concentration of substrate, and (iii) the cross-coefficients responsible for the induced effects due to the thermodynamic coupling. In order to study these effects, the ...

The field of nonequilibrium thermodynamics has been a popular one outside the United States, especially in Europe, and scientists there from various disciplines have published extensively on the use of nonequilibrium thermodynamics in a large variety of biological, chemical, and mechanical engineering applications. In contrast, the number of publications from North America has been relatively modest. Here, we review the field of nonequilibrium thermodynamics to assess its utility and impact in engineering and science. We find that developments in the fields thermodynamic optimality of processes, dissipative structures, coupled transport and rate processes, and biological systems suggest that in some circumstances nonequilibrium thermodynamics can be quite useful.

Hydroorganic mixtures are industrial solvents that can serve as media to solubilize either water in hydrocarbon or a hydrophobic substance in water. In many cases the solubilizing capability is obtained via a homogeneous complex aqueous mixtures containing an alcohol. Since excess heat capacity, C p E , is very sensitive to structural changes in mixtures, concentration and temperature dependence of C p E have been calculated by using the UNIQUAC model for the mixtures methanol(1)-water(2), ethanol(1)-water(2), and 1-propanol(1)-water(2). The temperature-dependent parameters of the model estimated directly from C p E data at more than one different isotherm are used in the calculations. The overall deviations between the calculated and experimental data points change in the range 6.52-10.15%, which indicates the satisfactory representation of C p E data by the model for engineering calculations. The temperature range of experimental data for the mixtures is 288.15 and 308.15 K. Surfaces of reduced, apparent, and partial molar excess heat capacities are also derived. The concentration and temperature dependencies of these functions suggest the existence of transitions of microstructure in the water-rich region, qualitatively similar to micellization. The surface of these thermodynamic functions facilitates a better understanding of thermodynamic properties and association of alcohol-water mixtures over a whole or certain concentration and temperature range. Such thermodynamic surfaces may be represented satisfactorily by the UNIQUAC model at low pressures