Natural gas hydrate

B. Kvamme. Mechanisms for initiation of hydrate from liquid water Liquid phase clustering, surface adsorbtion, or what In Proceedings Volume, pages 306-310. New York Acad Sci et al Natur Gas Hydrates Int Conf (New Paltz, NY, 6/20-6/24), 1993. 

A. R. Nerheim, T. M. Svartaas, and E. J. Samuelsen. Laser light scattering studies of natural gas hydrates. In Proceedings Volume, volume 2, pages 303-309. 69th Annu SPE Tech Conf (New Orleans, LA, 9/25-9/28), 1994. 

Dendy, E. and Sloan, ]., Fundamental principles and applications of natural gas hydrates. Nature, 426, 353,2003. 

ABSTRACT The Mallik gas hydrate field represents an onshore permafrost-associated gas hydrate accumulation in the Mackenzie Delta on the coast of the Beaufort Sea, Northwest Territories, Canada. This deposit contains a high concentration of natural gas hydrate with an underlying aquifer or free-gas zone at the base of the hydrate stability field. The physical and chemical properties of CH4 and C02 hydrates indicate the possibility of coincident C02 sequestration and CH4 production from the Mallik gas hydrate bearing zones. This study presents a numerical assessment of C02 sequestration and the recovery of CH4 from the gas hydrates at the Mallik site, Mackenzie Delta, Canada. 

The Beaufort-Mackenzie Basin hosts immense unconventional natural gas hydrate reserves that are often co-located with conventional petroleum resources. Osadetz et al. (2005) reported that the conventional resources are co-located with an immense gas hydrate resource estimated between 2.4 x 1012 and 87 x 1012 m3 of raw natural gas. Because the expected decline in conventional natural gas production from the Western Canada Sedimentary Basin cannot be replaced by conventional production from frontier regions alone, this immense hydrate resource offers a solution to replace the expected decline in conventional gas reserves. 

Currently, there are three possible gas recovery processes for hydrates (1) thermal stimulation, (2) depressurization and (3) inhibitor injection. Very limited thermal stimulation and depressurization tests were reported for the Mallik natural gas hydrate reservoirs, together with numerical simulations (Moridis et al. 2004,... 

Of special interest in recent years has been the analysis of natural gas hydrates that form in marine sediments and polar rocks when saline pore waters are saturated with gas at high pressure and low temperature. Large and 5D-variations of hydrate bound methane, summarized by Kvenvolden (1995) and Milkov (2005), suggest that gas hydrates represent complex mixtures of gases of both microbial and thermogenic origin. The proportions of both gas types can vary significantly even between proximal sites. 

Kvenvolden KA (1995) A review of the geochemistry of methane in natural gas hydrate. Org... 

Gas hydrates were first reported at the beginning of the 19th century, and until the 1930s they remained a scientific curiosity. At that time it was realized that hydrates were more likely to be the causative agent in blocking pipelines than ice. Today, gas hydrate control continues to be a problem in the oil and gas industry. In the 1960 s it was realized that natural gas hydrates are present in the geo-sphere with worldwide reserves estimated at 10,000 to 40,000 trillion cubic meters (TCM). Considerable efforts are underway to refine global estimates and to develop technology and exploit this resource. On the other hand these hydrates may... 

The idea here is to capture carbon dioxide from power plants and then inject it into natural gas hydrate reservoirs assumed to contain primarily methane hydrate. Thus one achieves the simultaneous sequestration of carbon dioxide with the production of natural gas. Lee et al. (2003) presented laboratory data that showed the replacement of methane molecules by C02. Yoon et al. (2004) and Ota et al. (2005) confirmed these laboratory findings. Park et al. (2006a) used a CO2/N2 mixture containing 20 mol % carbon dioxide (flue gas) instead of pure C02 and noticed that the methane recoveiy increased from 64 to 85 %. A similar idea for sequestering captured C02 is to use it as cushion gas for natural gas storage in reservoirs (Oldenburg, 2003). 

Ota, S. Uetani, H. Kawano, H. (2002). Use of hydrate pellets for transportation of natural gas - III - safety measures and conceptual design of natural gas hydrate pellet carrier. Proc. Fourth Int. Con. Gas Hydrate, Yokohama, Japan, Vol. I 991-996. 

Sloan, E.D. (2004b). Thermodynamics of Natural Gas Hydrates, in Chemical Thermodynamics for Industry, Fletcher, T.M., (editor), RSC, chapter 6. 

Sloan, E.D. Phase Equilibria of Natural Gas Hydrates, paper presented at 63rd Annual GPA Convention, New Orleans, March 19-21, 1984. 

Natural gas hydrates are crystalline solids composed of water and gas. The gas molecules (guests) are trapped in water cavities (host) that are composed of hydrogen-bonded water molecules. Typical natural gas molecules include methane, ethane, propane, and carbon dioxide. 

Historically, the research efforts on natural gas hydrates can be classified into three landmark phases that cover the following periods ... 

As a result, the present is a culmination of three periods, representing the most fascinating and productive time in the history of natural gas hydrates. During the first century after their discovery, the number of hydrate publications totaled approximately 40 in modern times, the number of hydrate publications, both in the technical and in the popular press, has increased dramatically with over 400 publications in 2005 alone. The semilogarithmic plot of Figure 1.1 illustrates the exponential growth in the number of hydrate-related publications in the twentieth century. Table 1.1 lists reviews, chapters, and monographs on the subject of hydrates. 

Natural gas hydrates were first documented by Sir Humphrey Davy (1811), with these brief comments on chlorine (then called oxymuriatic gas) in the Bakerian lecture to the Royal Society in 1810. 

Sloan, Happel and Hnatow, eds. International Conference on Natural Gas Hydrates, NY... 

Kvenvolden, K.A. A Review of the Geochemistry of Methane in Natural Gas Hydrate... 

Pauli and Dillon, eds. Natural Gas Hydrates Occurrence, Distribution and Detection... 

Johnson et al., eds. Economic Geology of Natural Gas Hydrates 2006 Trehu et al. Ocean Drilling Program Scientific Report Leg 204... 

In the mid-1930s Hammerschmidt studied the 1927 hydrate review of Schroeder (D.L. Katz, Personal Communication, November 14, 1983) to determine that natural gas hydrates were blocking gas transmission lines, frequently at temperatures above the ice point. This discovery was pivotal in causing a more pragmatic interest in gas hydrates and shortly thereafter led to the regulation of the water content in natural gas pipelines. 

Collett, T.S., Detection and Evaluation of Natural Gas Hydrates from Well Logs, Prudhoe Bay Alaska, M.S. Thesis, University of Alaska (1983). 

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