The characteristics of the hydrate-bearing sediments affect the formation and dissociation of gas hydrate in sediments. The mineral composition, their dispersion, and chemical composition of hydrate-bearing sediment samples plays a dominant role in the hydrate stability condition and its economic development. In this paper, the physical properties of hydrate-bearing sediment of India are compared with each other. The sediment samples are taken from the Krishan-Godavari basin (Depth—127.5 and 203.2 mbsf), Mahanadi basin (Depth—217.4 mbsf), and Kerala-Konkan basin (Depth—217.4 mbsf). The saturation of the gas hydrate observed at these sites is between 3 and 50%. Particle size is an important parameter of the sediments because it provides information on the transportation and deposition of sediment and the deposition history. In the present study, we investigated the mineralogy of hydrate-bearing sediments by chemical analysis and X-ray Diffraction. XRD, FTIR, and Raman Spectroscopy distinguished the mineralogical behavior of sediments. Quartz is the main mineral (66.8% approx.) observed in the gas hydrate-bearing sediments. The specific surface area was higher for the sediment sample from the Mahanadi basin, representing the sediments’ dissipation degree. This characterization will give important information for the possible recovery of gas from Indian hydrate reservoirs by controlling the behavior of host sediment. SEM analysis shows the morphology of the sediments, which can affect the mechanical properties of the hydrate-bearing sediments. These properties can become the main parameters to consider for the design of suitable and economic dissociation techniques for gas hydrates formed in sediments.

A fugacity-based thermodynamic model for hydrate has been used to determine the equilibrium pressures of hydrate formation. This fugacity-based model uses the PRSV equation of state, which is used to represent the gas phases in the hydrate. The parameters of the model are fitted to the experimental data of binary guest hydrates. The present study is aimed at investigating binary mixtures of {\text{CH}_{4}} – {\text{H}_{2}} S, {\text{C}_{3}}{\text{H}_{8}} – {\text{N}_{2}} , {\text{N}_{2}} – {\text{CO}_{2}} , {\text{CH}_{4}} –i-butane, {\text{C}_{3}}{\text{H}_{8}} –i-butane, {\text{CH}_{4}} –n-butane, {\text{C}_{3}}{\text{H}_{8}} –n-butane, i-butane– {\text{CO}_{2}} , and n-butane– {\text{CO}_{2}} hydrates, which have not been modeled before. Unlike previous studies, the Kihara potential parameters were obtained using the second virial coefficient correlation and the data of viscosity for gases. The fugacity-based model provides reasonably good predictions for most of the binary guest hydrates ( {\text{CH}_{4}} – {\text{C}_{3}}{\text{H}_{8}} ). However it does not yield good prediction for hydrates of ( {\text{CO}_{2}} – {\text{C}_{3}}{\text{H}_{8}} ). The transitions of hydrate structure from sI to sII and from sII to sI have been also predicted by this model for binary guest hydrates. The AAD % calculated using the experimental data of natural gas hydrates is only 10 %, which is much lower than the AAD % calculated for the equilibrium data predicted by the VdP-w model.

The formation of gas hydrates in the pipelines of oil, gas, chemical, and other industries has been a significant problem for many years because the formation of gas hydrates may block the pipelines. Hence, the knowledge of the phase equilibrium conditions of gas hydrate became necessary for the economic and safe working of oil, gas, chemical industries. Various thermodynamic approaches with various mathematical techniques are available for the prediction of formation conditions of gas hydrates. In this chapter, the authors have discussed the least square support vector machine and artificial neural network models for the prediction of stability conditions of gas hydrates and the use of genetic programming (GP) and genetic algorithm (GA) to develop a generalized correlation for predicting equilibrium conditions of gas hydrates.

Natural gas hydrate (NGH) has emerged as a future source of energy for the world that can fulfill the future energy demand. The natural gas hydrates hold twice the amount of energy than all available fossil fuels. At present, the energy demand is growing, but these are not available commercially. Various field applications on the dissociation of the natural gas hydrates have been performed till now, and the output of these field applications confirms the possibility of dissociation of the natural gas hydrates. At distinct locations in the world, the huge deposits of hydrates have been identified, but the safe and economic dissociation of gas hydrates is not known yet. Hence, the evolution of new and inexpensive, suitable methods and technologies are required for the dissociation of gas hydrates. In this chapter, the authors reviewed several articles to compare the different dissociation techniques of gas hydrates and their field applications. The advantages and disadvantages of these production methods have also been discussed. Request access from your librarian to read this chapter's full text.