Flow process thermodynamic analysis

Real irreversible processes can be subjected to thermodynamic analysis. The goal is to calciilate the efficiency of energy use or production and to show how energy loss is apportioned among the steps of a process. The treatment here is limited to steady-state, steady-flow processes, because of their predominance in chemical technology. 

Numerous case studies, examples, and problems illustrate the thermodynamic analysis of process performance to explain how to effectively analyze and optimize work flows and environmental resources. The authors compare the present industrial society with an emerging one in which mass production and consumption are in harmony with the natural environment through closure of material cycles. In this second edition, the book s structure of Basics, Thermodynamic Analysis of Processes, Case Studies, and Sustainability has been unaffected, but a few additions have been made. 

A simplified flow diagram for this segment of the process is shown in Figure 4, and thermodynamic analysis in Table III. The refrigerated exchangers and cold box represent about 30% of the lost work of the process. However, the tower itself has a very high percentage of the lost work in the system. Thus the details of the tower heat and material balance were examined in search of ways to improve its efficiency. 

THERMODYNAMIC ANALYSIS OF STEADY-STATE FLOW PROCESSES... 

Thermodynamic Analysis of Steady-State Flow Processes... 

We have used this chapter to illustrate how thermodynamics can contribute to the analysis and design of selected engineering processes. The applications considered here included calculations for phase equilibria, solubilities, heat effects in steady-flow processes, and the response of certain variables to changes of state. 

Water at 50 °C is to be cooled to in a flow process to 30 °C. This can be done either by mixing it with ice at O "C, or with water at 25 °C. Perform a second-law analysis of this process to determine which method is thermodynamically more efficient. 

Exergy analysis is a relatively new method of thermodynamic analysis that has recently been applied in different fields of engineering and science 10). The exergy method takes into account not only the quantity of materials and energy flows, but also their quality. The main reason of exergy analysis is to detect and evaluate quantitatively the losses that occur in thermal and chemical processes. 

Relations between the theories of states and trajectories and capabilities of equilibrium thermodynamic analysis to study reversible and irreversible kinetics can be more fully revealed by considering another type of models of extreme intermediate states, namely MEIS of hydraulic circuits (Gorban et al., 2001, 2006 Kaganovich et al., 1997, 2007, 2010). Convenience and clearness of using these models to describe the considered problems are determined by the fact that they are intended to study an essentially irreversible process, i.e. motion of a viscous fluid. Besides, they can be treated as models of the mechanism of fluid transportation from the specified source nodes of a hydraulic system to the specified consumption nodes. The major variable of the hydraulic circuit theory (Khasilev, 1957,1964 Merenkov and Khasilev, 1985), i.e. continuous medium flow, has an obvious kinetic sense. 

For analysis purposes, the equations for conservation mass and the first law of thermodynamics are simplified with some assumptions. Two such common cases are (i) the steady-state steady-flow process and (ii) the uniform-flow uniform-state process. 

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