Abstract: A method for dumping carbon dioxide gas into the ground of the sea bottom comprises injecting carbon dioxide gas into the ground of the sea bottom to fix the carbon dioxide gas in the ground of the sea bottom. A method for dumping carbon dioxide gas into the ground of permafrost regions comprises boring a well and injecting carbon dioxide into the ground to fix carbon dioxide in the ground. A method for recovering and consuming natural gas found in the ground of permafrost regions with low pollution comprises exploiting and consuming hydrate of natural gas present in permafrost regions to produce carbon dioxide as a by-product and injecting the carbon dioxide by-product into the ground of permafrost. A method for gathering natural gas by using dumped carbon dioxide gas as a heat generating source comprises injecting carbon dioxide gas or liquefied carbon dioxide gas into layers of hydrate of natural gas present in the ground of the sea bottom or in permafrost regions.

Abstract: A method for manufacturing ice containing carbon dioxide comprises a process wherein ice grains or water as material used for ice containing carbon dioxide is charged into a pressure vessel, a process wherein the material is enveloped in an atmosphere of carbon dioxide and a process wherein a temperature and a pressure of the material is adjusted so that the temperature and the pressure can be values in the range enclosed with straight lines connecting the following points and A point in this order:A: 0.degree. C.: 2 kg/cm.sup.2B: 0.degree. C.: 2 kg/cm.sup.2C: -7.degree. C.: 1000 kg/cm.sup.2D: -21.degree. C.: 1900 kg/cm.sup.2E: -50.degree. C.: 440 kg/cm.sup.2F: -57.degree. C.: 100 kg/cm.sup.2G: -57.degree. C.: 2 kg/cm.sup.2Another method for manufacturing ice containing carbon dioxide comprises a process wherein a temperature and a pressure inside the pressure vessel are adjusted to the range and a process wherein carbonic acid water containing carbon dioxide is injeced in an antifreeze liquid.

Abstract: A method for manufacturing ice comprising the steps of: supplying gas into a pressure-resistant vessel containing ice grains, the pressure of the supplied gas being kept increased; applying a press force to the ice grains to increase the density of the ice grains, contact portions of the ice grains being allowed to be melted; and cooling the ice grains, in the pressed state, to freeze the ice grains. Gas to be introduced into the vessel is at least one selected from those of air, oxygen and carbon dioxide. An apparatus used for the method is also provided.