Well engineering concepts to make methane gas hydrate exploitation affordable.

Abstract

There are anticipated to be substantial global deposits of land and seabed methane gas hydrates. The volume of methane gas trapped in these methane gas hydrates is calculated to be at least twice the volume of current global reserves of oil & gas as reviewed by the United Nations. These methane gas hydrates are deemed important as a future energy resource, and several companies and countries are looking at the effective exploitation of the resource for methane gas supply. If safe economic exploitation could be achieved the world will have an energy resource that would be able to support the demands for century's to come. The chemistry, physics and geological setting of the natural hydrates make them difficult to exploit using convention hydrocarbon well engineering techniques. The major nations of the world such as the United States of America, Japan, Canada, France and Germany are investing heavily in research and development to gain a better understanding of the gas hydrate energy source. It is an area that we will see confirmed as a major energy source for the world, provided the costs of development can be reduced. In the perma frost land environment and deep sea marine environment Hydrates have traditionally been seen as a major risk to Drilling operations and have been implicated with many drill well blowouts world wide. This thesis critically reviews the existing industry approaches to hydrate exploitation and proposes several new well engineering techniques, which could be applied to effect successful resource recovery. This thesis derives the conclusion that by an enhanced understanding of the deposit area and by the application of new well technology and varied procedures, methane exploitation will be possible. The thesis focused on three areas to reduce cost of development: 1. Low cost, low complexity, subsea systems to drill produce and maintain developments. 2. Utilisation of fit for purpose low cost vessels to conduct the field development drilling and completion. 3. Seabed drilling topdrive system to enable rapid drilling of the development.