Device of supplying a concentrated CO.sub.2 gas in a carbonate spring bath system

A device of supplying a concentrated CO.sub.2 gas in a carbonate spring bath system for creating a bath water dissolved with CO.sub.2 gas and supplying the same to a bathtub, said device comprising:

• a CO.sub.2 gas source supplying a concentrated CO.sub.2 gas to dissolving means which dissolves the CO.sub.2 gas supplied from said CO.sub.2 gas source under a pressurized condition into the bath water being fed to said bathtub;
• said CO.sub.2 gas source comprising:
• combustion means for obtaining from a hydrocarbon fuel a combustion gas containing a CO.sub.2 gas;
• a CO.sub.2 adsorption tower connected to said combustion means through a gas feed line to receive said combustion gas and connected to said dissolving means through a supply line, said CO.sub.2 adsorption tower being filled with an adsorbent capable of adsorbing the CO.sub.2 gas from said combustion gas at a relatively low adsorption temperature and of desorbing the CO.sub.2 gas therefrom at a relatively high desorption temperature for feeding the CO.sub.2 gas to said dissolving means through said supply line;
• cooling means disposed in said gas feed line between said combustion means and said CO.sub.2 adsorption tower to cool said combustion gas prior to being fed to said CO.sub.2 adsorption tower;
• heating means disposed within said CO.sub.2 adsorption tower in order to heat said adsorbent for desorbing said CO.sub.2 gas therefrom;
• a gas discharge line extending from said CO.sub.2 adsorption tower in communication with said gas feed line so as to discharge said combustion gas out of said CO.sub.2 adsorption tower after adsorption of the CO.sub.2 gas from said combustion gas to said adsorbent;
• a cooling line extending from said CO.sub.2 adsorption tower and terminating in said gas feed line upstream of said CO.sub.2 adsorption tower so as to be cooperative with said gas feed line to form a closed loop for circulating a residual gas through said CO.sub.2 adsorption tower in order to cool said adsorbent thereby.