Plenary Lecture
A New Frontier in Marine Technology – Gas Hydrates, as a Source of
Energy and as a Means of Natural Gas Transportation
Professor Deniz Unsalan
Piri Reis University
Istanbul, Turkey
E-mail: denizunsalan@yahoo.com
Abstract: Gas hydrates, or clathrates, are polyhedral shaped
crystalline structures which certain gases, mainly light alkanes, form
with water under moderately low temperature (of a few centigrades) and
high pressure (of about 3 megapascals) conditions. When heated to
near-room temperatures or when the pressure upon them is released, they
yield the two ingredient components, which one of them is the natural
gas.
Gas hydrates are found in nature at the depths of seas exceeding 300
metres, mixed with bottom sediments or under the arctic permafrost
layer. It is estimated that most of the methane content of the earth is
in the form of gas hydrates just beneath the sea floor, which one of
them is the Black Sea. However, the high hydrostatic pressure levels at
those depths pose a challenge for the marine technologists who want to
exploit this new opportunity. The paper to be presented has a proposal
for an extraction scheme for the gas hydrates in the depths of the seas.
Another aspect of gas hydrates is that they offer a fourth alternative
for the transportation of gas hydrates, in addition to the existing
means (pipelines, liquefied natural gas (LNG) and compressed natural
gas(CNG)). By this way, it is possible to avoid the high pressures of
the CNG and cyrogenically low temperatures of the LNG concepts. A
unitized cargo transportation scheme derived from the lighter aboard
ship (LASH) concept for the transportation and storage of natural gas in
gas hydrate form is presented and candidate ship forms for that concept
are presented.
Brief Biography of the Speaker:
Deniz Unsalan was born in Izmir, Turkey in 1953. He was educated in
Ankara and Istanbul, receiving his undergraduate education from the
Turkish Naval Academy in 1973. He served in the Turkish Navy ships
before and after his postgraduate education. He received "Master of
Science" and "Mechanical Engineer" degrees from the Naval Postrgraduate
School at Monterey, California in 1980. He was a British Council Scholar
at the University of Newcastle upon Tyne, U.K. between 1982-1984. He
received his Doctor of Philosophy degree in Naval Architecture in 1993
from the Istanbul Technical University.
He was a lecturer in Marine Engineering at the Turkish Naval Academy
between 1987 and 1994, Assistant Professor at Istanbul Technical
University Maritime Faculty between 1994 and 1996, Associate Professor
at Near East University in Cyprus between 1996-2003, at Dokuz Eylul
University Institute of Marine Sciences and Technology between
2003-2006. He became a full Professor in 2006. He will start his new
post as the Professor of Marine engineering at the Piri Reis University
in Istanbul, Turkey on September 2009.