Estimation Techniques for Phase Equilibria of Natural Gas Hydrates

Substantially different from ice, the phase equilibria of natural gas hydrates represents the most important set of hydrate properties. In contrast to kinetic phenomena, hydrate phase equilibria are well defined and determine a boundary to the kinetic problem. This chapter addresses hydrate phase equilibria with approximate methods that provide an understanding of the phenomena involved. 

Engineers may ask, When I plan to use a simulation package such as ASPEN PLUS , PRO II , UNISIM , or even the CD provided with this book, why should I be concerned with simpler, less accurate methods of phase equilibria and diagrams If I m concerned with accuracy, why not use two prediction packages and compare the result  

The answer addresses one of the key modern engineering dilemmas, that of providing engineering judgment to evaluate calculations from black-box complex computer codes. Computer programs may provide a number that may not be a good model of physical reality. The simpler methods in this chapter are very valuable, first for intuitive understanding and second to provide both a first estimation and a check of more complex calculations. 

At the conclusion of this chapter, the engineer should be able to answer questions such as the following  

What are pressure-temperature-composition bounds on si and sll hydrate formation  

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A Estimation Techniques for Phase Equilibria of Natural Gas Hydrates... 

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