Plant operator, thermodynamics importance

The previous section has described how engineering simulations are valuable in improving plant operations. To produce accurate results, several composition-based properties are required to model the melt—its density, specific heat capacity, and dissolution thermodynamics— but the most important properties are the viscosity and thermal conductivity. 

At this point, the final specifications for the one or two chosen product(s) after selection process should be identified. This can be done using a three-step procedure. First, we define the product micro and macrostructure. Second, we rank the product s most important attributes, an effort that forces a review of how the product will be used. Third, we review any chemical triggers, that is, chemical stimuli which cause major changes in product properties. Finally, we turn to the manufacture itself, which relies on technical know-how of thermodynamics, chemical reaction kinetics, transport phenomena, and unit operations. Some of these ideas are illustrated in the following example. Except for a schematic of the manufacturing process, the many details related to the manufacturing plant are omitted in this discussion. 

The importance of chemistry to the nuclear power industry is now well recognized. Chemical control in water circuits is an accepted part of the operating requirements of nuclear generating stations, as it is for modern fossil-fired stations. While there have been major advances in knowledge of the chemistry of aqueous systems at temperatures above lOQoC, there is still a need for further work. As we improve our understanding of thermodynamics and kinetics of solid-aqueous reactions and the effect of radiation on them, we can expect further advances in controlling radiation fields in reactor circuits and in minimizing iron deposition in GS plants. 

Complex thermal systems cannot usually be optimized using mathematical optimization techniques. The reasons include system complexity opportunities for structural changes not identified during model development incomplete cost models and inability to consider in the model additional important factors such as plant availability, maintenability, and operability. Even if mathematical techniques are applied, the process designer gains no insight into the real thermodynamic losses, the cost formation process within the thermal system, or on how the solution was obtained. 

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