Gas hydrates represent one of the world’s largest untapped reservoirs of energy and, according to some estimates, have the potential to meet global energy needs for the next thousand years. "Methane Gas Hydrate" examines this potential by focusing on methane gas hydrate, which is increasingly considered a significant source of energy. "Methane Gas Hydrate" gives a general overview of natural gas, before delving into the subject of gas hydrates in more detail and methane gas hydrate in particular. As well as discussing methods of gas production, it also discusses the safety and environmental concerns associated with the presence of natural gas hydrates, ranging from their possible impact on the safety of conventional drilling operations to their influence on Earth’s climate. "Methane Gas Hydrate" is a useful reference on an increasingly popular energy source. It contains valuable information for chemical engineers and researchers, as well as for postgraduate students.
Gas hydrates represent one of the world’s largest untapped reservoirs of energy and, according to some estimates, have the potential to meet global energy needs for the next thousand years. "Methane Gas Hydrate" examines this potential by focusing on methane gas hydrate, which is increasingly considered a significant source of energy. "Methane Gas Hydrate" gives a general overview of natural gas, before delving into the subject of gas hydrates in more detail and methane gas hydrate in particular. As well as discussing methods of gas production, it also discusses the safety and environmental concerns associated with the presence of natural gas hydrates, ranging from their possible impact on the safety of conventional drilling operations to their influence on Earth’s climate. "Methane Gas Hydrate" is a useful reference on an increasingly popular energy source. It contains valuable information for chemical engineers and researchers, as well as for postgraduate students.
1. THE BEGINNINGS OF HYDRATE RESEARCH Until very recently, our understanding of hydrate in the natural environment and its impact on seafloor stability, its importance as a sequester of methane, and its potential as an important mechanism in the Earth's climate change system, was masked by our lack of appreciation of the vastness of the hydrate resource. Only a few publications on naturally occurring hydrate existed prior to 1975. The first published reference to oceanic gas hydrate (Bryan and Markl, 1966) and the first publication in the scientific literature (Stoll, et a1., 1971) show how recently it has been since the topic of naturally occurring hydrate has been raised. Recently, however, the number of hydrate publications has increased substantially, reflecting increased research into hydrate topics and the initiation of funding to support the researchers. Awareness of the existence of naturally occurring gas hydrate now has spread beyond the few scientific enthusiasts who pursued knowledge about the elusive hydrate because of simple interest and lurking suspicions that hydrate would prove to be an important topic. The first national conference on gas hydrate in the U.S. was held as recently as April, 1991 at the U.S. National Center of the U.s. Geological Survey in Reston Virginia (Max et al., 1991). The meeting was co-hosted by the U.s. Geological Survey, the Naval Research Laboratory, and the U.S.
Natural Gas Hydrates, Fourth Edition, provides a critical reference for engineers who are new to the field. Covering the fundamental properties, thermodynamics and behavior of hydrates in multiphase systems, this reference explains the basics before advancing to more practical applications, the latest developments and models. Updated sections include a new hydrate toolbox, updated correlations and computer methods. Rounding out with new case study examples, this new edition gives engineers an important tool to continue to control and mitigate hydrates in a safe and effective manner. - Presents an updated reference with structured comparisons on hydrate calculation methods that are supported by practical case studies and a current list of inhibitor patents - Provides a comprehensive understanding of new hydrate management strategies, particularly for multiphase pipeline operations - Covers future challenges, such as carbon sequestration with simultaneous production of methane from hydrates
This book is a companion to “Natural Gas Hydrate in Oceanic and Permafrost Environments” (Max, 2000, 2003), which is the first book on gas hydrate in this series. Although other gases can naturally form clathrate hydrates (referred to after as ‘hydrate’), we are concerned here only with hydrocarbon gases that form hydrates. The most important of these natural gases is methane. Whereas the first book is a general introduction to the subject of natural gas hydrate, this book focuses on the geology and geochemical controls of gas hydrate development and on gas extraction from naturally occurring hydrocarbon hydrates. This is the first broad treatment of gas hydrate as a natural resource within an economic geological framework. This book is written mainly to stand alone for brevity and to minimize duplication. Information in Max (2000; 2003) should also be consulted for completeness. Hydrate is a type of clathrate (Sloan, 1998) that is formed from a cage structure of water molecules in which gas molecules occupying void sites within the cages stabilize the structure through van der Waals or hydrogen bonding.
Gas hydrates are ice-like crystalline substances that form a rigid cage of water molecules and entrap hydrocarbon and non-hydrocarbon gas by hydrogen bonding. Natural gas hydrate is primarily composed of water and methane. These are solid, crystalline, ice-like substances found in permafrost areas and deepwater basins around the world. They naturally occur in the pore space of marine sediments, where appropriate high pressure and low temperature conditions exist in an adequate supply of gas (mainly methane). Gas hydrates are considered as a potential non conventional energy resource. Methane hydrates are also recognized as, an influence on offshore platform stability, a major factor in climate change contributing to global warming and a significant contribution to the ocean carbon cycle. The proposed book treats various geophysical techniques in order to quantify the gas hydrate reserves and their impact on environment. The primary goal of this book is to provide the state of art for gas hydrate exploration. The target audiences for this book are non-specialist from different branches of science, graduate students and researchers.
The book is an up-to-date basic reference for natural gas hydrate (NGH) in the Arctic Ocean. Geographical, geological, environmental, energy, new technology, and regulatory matters are discussed. The book should be of interest to general readers and scientists and students as well as industry and government agencies concerned with energy and ocean management. NGH is a solid crystalline material that compresses gas by about a factor of about 164 during crystallization from natural gas (mainly methane) - rich pore waters over time. NGH displaces water and may form large concentrations in sediment pore space. Its formation introduces changes in the geotechnical character of host sediment that allows it to be distinguished by seismic and electric exploration methods. The chemical reaction that forms NGH from gas and water molecules is highly reversible, which allows controlled conversion of the NGH to its constituent gas and water. This can be achieved rapidly by one of a number of processes including heating, depressurization, inhibitor injection, dissolution, and molecular replacement. The produced gas has the potential to make NGH a valuable unconventional natural gas resource, and perhaps the largest on earth. Estimates for NGH distribution, concentration, economic targets, and volumes in the Arctic Ocean have been carried out by restricting the economic target to deepwater turbidite sands, which are also sediment hosts for more deeply buried conventional hydrocarbon deposits. Resource base estimates are based on NGH petroleum system analysis approach using industry-standard parameters along with analogs from three relatively well known examples (Nankai-Japan, Gulf of Mexico-United States, and Arctic permafrost hydrate). Drilling data has substantiated new geotechnical-level seismic analysis techniques for estimating not just the presence of NGH but prospect volumes. In addition to a volumetric estimate for NGH having economic potential, a sedimentary depositional model is proposed to aid exploration in the five different regions around the deep central Arctic Ocean basin. Related topics are also discussed. Transport and logistics for NGH may also be applicable for stranded conventional gas and oil deposits. Arising from a discussion of new technology and methodologies that could be applied to developing NGH, suggestions are made for the lowering of exploration and capital expenses that could make NGH competitive on a produced cost basis. The basis for the extraordinarily low environmental risk for exploration and production of NGH is discussed, especially with respect to the environmentally fragile Arctic region. It is suggested that because of the low environmental risk, special regulations could be written that would provide a framework for very low cost and safe development.
The occurrence of gas hydrates in large quantities worldwide, and their immense energy potential have prompted concerted efforts into their exploration and understanding over the last many years. During this time, geophysical characterization of natural gas hydrate occurrences by seismic and other methods have gained prominence, and such studies have been reported from time to time. However, no compilation of such studies was ever attempted. This SEG publication, Geophysical Characterization of Gas Hydrates (Geophysical Developments No. 14), is the first book on the topic that focuses on documenting various types of geophysical studies that are carried out for the detection and mapping of gas hydrates.
