(JP4292775-A)      CO2 gas is disposed of in great amounts under the sea to and into the seabed to fix it there.    CO2 gas can be injected from the depth where no gaseous hydrated CO2 is formed in the seabed or CO2 remains in the form of liquefied or gaseous hydrated CO2 in the seabed.    USE/ADVANTAGE -   The method can effectively dispose of CO2 gas in great amounts to even shallow seabed without damaging the biological environment near the seabed because the CO2 gas can remain in the form of liquefied CO2 and/or gaseous hydrated CO2. The method contributes to the prevention of temperature-raising phenomenon of the earth    (JP4292776-A)      C02 gas is injected into a well formed in a cold area at high latitude to form gaseous hydrate of C02 in the ground to fix it. The well is excavated to a depth at which the gaseous hydrate can form or below the permafrost soil layer and C02 gas is injected into the well.    Typically C02 discharged during the comsumption of natural gas gaseous hydrate which is taken from the permafrost soil layer in the cold area, is converted into gaseous hydrate and discharged.    USE/ADVANTAGE -   The method can effectively and exactly fix C02 gas without causing damage to biological environment and global warming    (JP5025986-A)      A natural gas prodn. comprises forcing tipping gas or liq. carbon dioxide into a natural gas hydrated layer which exists on the sea bed or the permafrost region and the tipping carbon dioxide is fixed as the gas hydrate and the natural gas is produced by the detaching from the natural gas hydrate with the sensible heat or the latent heat of the carbon dioxide.    USE/ADVANTAGE -   The natural gas can be produced and the tipping cost of the carbon dioxide can be decreased.    A forcing pipe pref. perforates the ground and the down part of the pipe inserted into a hydrate layer of the natural gas and the carbon dioxide is perforated through a perforation pipe and a suction pipe with a perforation device and the natural gas is produced through producing pipes    (US5261490-A)      In the dumping of CO2 gas into the sea bed, a well is bored, a pipe is set in the well and the gas is injected into the sea bed so that it contacts sea water which has penetrated into the sea bed and produces a hydrate which fixes the gas and remains in the sea bed. The gas may also be retained in the sea bed by injection below a layer in which the hydrate has been formed.    Gas may also be dumped by injecting into the earth below an impermeable layer, and the methods may also be used in a permafrost region on land. Dumped CO2 may be used as a heat source to release natural gas from layers of its hydrate which exist at depths of 750m or less under the sea surface or in a permafrost region in ground with a load of 7.5 MPa by injecting the CO2 into the hydrate and pumping up the dissociated natural gas.    ADVANTAGE -   Provides a range of methods for disposing of and/or utilising CO2 e.g. exhausted from industrial furnaces.