Japanese Companies Start Making Iceblocks

Credit: Mitsui

By The Maritime Executive 09-14-2019 06:25:38

Mitsui E&S Holdings, Mitsui E & S Shipbuilding and Kitami Institute of Technology have started to develop a way of making big ice blocks which simulate the ice-like solid of shallow methane hydrate.

The seabed of Japan's exclusive economic zone (EEZ) contains various resources including shallow methane hydrates, sandy layer type methane hydrates, sea-floor hydrothermal deposits and cobalt rich crusts, and the nation aims to harvest these resources.

Shallow methane hydrate, an ice-like solid material composed of water and methane molecules, can only exist in stable form under the low-temperature, high-pressure conditions of the seabed. It's molecular structure is a cage-like lattice of ice inside which are trapped molecules of methane, the chief constituent of natural gas. When brought to the earth's surface, one cubic meter of gas hydrate releases 164 cubic meters of natural gas. 

The companies are investigating a method for harvesting using a large-diameter drill. The simulated ice will be used to acquire design data of the drilling equipment - something simpler to do on land rather than on the seabed in over 400 meters of water. Also involved in the project are MHWirth GmbH.

Going forward, Mitsui will develop subsea mining technologies, offshore drilling systems, lifting and recovery technologies.

Hydrate deposits may be several hundred meters thick, they have been found around the world. Estimates of worldwide reserves range from 280 trillion cubic meters (10,000 trillion cubic feet) up to 2,800 trillion cubic meters (100,000 trillion cubic feet), according to the U.S. Energy Information Administration. Along with Japan, China, the U.S. and India also have research underway on the fuel.