The Gas-In-Ice concept has been patented by Professor Gudmundsson at the Norwegian Institute of Technology (NTH) in cooperation with Aker Engineering. An early stage evaluation was done by Hveding in 1994~\cite{frode}. The concept is now undergoing a more detailed study than earlier, and some rough engineering work and cost estimates have been done~\cite{aker}. In addition a project group of several possible future participants is being formed. The idea is to obtain fundings for building a pilot plant so the main assumptions of the concept can be verified on a larger scale as a basis for a future industrial process.
Gas hydrates have throughout the development of the petroleum industry almost without exceptions been seen as a problem due to plugging of pipelines and process equipment. Due to this, most of the work done on gas hydrates has focused on hydrate prevention and inhibition~\cite{katz}. However, recent work done on the Gas-in-Ice concept has considered hydrates from the other side and tried to obtain knowledge from a "positive" point of view using both experience from earlier work and new knowledge. The experimental work done at NTH has been implemented with simple but convenient laboratory equipment.
The overall purpose of the Gas-in-Ice concept is to store/transport gas as efficiently and cost effective as possible. This is dependent upon several parameters, but the main ones affecting the hydrate process are said to be rate of formation, gas content and the stability of hydrates. The work done at NTH has focused on these parameters, but the work is far from completely answering all the questions asked.
The main challenge of this study is to produce gas hydrates with as high gas content as possible. This will include an experimental phase for separating hydrate from liquid water and also to look at the methods used in the industry for separating solid-liquid slurries. The effect of some additives on separation efficiency and rate of formation will also be investigated.
The rate of formation can be affected by additives, molecular or solid, as shown in this experimental work.
Separation of hydrate/water slurry by settling is very difficult. The separation was not improved using different filters.
The potential for storing large amounts of gas in hydrates have been proven, even though sufficient separation was not obtained.
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