1. Field of the Invention
The present invention relates to the field of environmental control concerning sewage treatment, stack gas desulfurization, garbage treatment and livestock waste disposal as well as the fields of carbon black production, methanol production, dimethyl ether production and gasoline production.
2. Description of the Prior Art
According to estimated data related to the carbon cycle by the intergovernmental panel on climatic change (IPCC), artificially discharged carbon dioxide (CO.sub.2) amounts to about 71 hundred million tons a year in terms of carbon. It is considered that about half remains in the atmosphere while the other half is absorbed by the sea and others. Carbon dioxide, known as greenhouse effect gas, is regarded as a cause for global warming.
In order to reduce the concentration of carbon dioxide in the atmosphere, it is indispensable to suppress the discharge thereof itself. Various methods are studied for reducing the discharge of carbon dioxide.
A method of reducing carbon dioxide under a hydrogen (H.sub.2) atmosphere and converting the same to pulverized carbon has been devised in order to fix carbon dioxide contained in the atmosphere or discharged in great volume from power plants, steelworks, or heavy and chemical plants on the discharge source, and recycle the same. The conversion system therefore is formed by a carbon dioxide separator for separating carbon dioxide from the atmosphere or exhaust gas, a carbon dioxide concentrator for concentrating the separated carbon dioxide, a CO.sub.2 /H.sub.2 reactor for forming pulverized carbon by reacting the carbon dioxide with hydrogen under the presence of a catalyst and the like.
While electrolysis of water, solar battery power generation, utilization of hydrogen absorbing alloys or the like has been proposed as a method of obtaining hydrogen necessary for converting carbon dioxide to pulverized carbon and fixing the same, a carbon dioxide fixing apparatus has not yet been put into practice since hydrogen is extremely costly.