Air conditioning and thermal storage systems using clathrate hydrate slurry

Abstract

The present invention includes a method and apparatus for making a hydrate slurry, which prepare an aqueous solution of a guest compound for forming a clathrate hydrate, cool the aqueous solution, and contact a nuclear particles; furthermore, a thermal storage method, a thermal storage apparatus, and a thermal storage medium by using an aqueous solution of clathrate hydrate, whose concentration is a congruent melting point or lower; furthermore, an refrigerating apparatus and an air conditioner for using the thermal storage method, the thermal storage apparatus and the thermal storage medium.

What is claimed is:  
     
         1 . A method for making a hydrate slurry comprising the steps of: 
 (a) preparing an aqueous solution of a guest compound for forming a clathrate hydrate in a channel of the aqueous solution;    (b) cooling the aqueous solution to form a hydrate particles in the aqueous solution;    (c) cooling the aqueous solution being circulated by a heat transfer face; and,    (d) contacting a nuclear particles with a surface of a member in the circulated aqueous solution to form the hydrate particles.    
     
     
         2 . The method of    claim 1   , wherein the nuclear particles are the hydrate particles.  
     
     
         3 . The method of    claim 1   , wherein the nuclear particles are fine particles.  
     
     
         4 . The method of    claim 3   , further comprising the steps of 
 precipitating the fine particles having a higher gravity than the aqueous solution; and    supplying the precipitated fine particles to the circulated aqueous solution to float the fine particles in the aqueous solution.    
     
     
         5 . The method of    claim 4   , further comprising the step of 
 supplying the fine particles being precipitated on the bottom of the channel for the aqueous solution.    
     
     
         6 . The method of    claim 4   , further comprising the step of 
 adhering the fine particles to the surface of the member in contact with the circulated aqueous solution.    
     
     
         7 . The method of    claim 1   , wherein the fine particles have a specific gravity equal to the specific gravity of the aqueous solution and float in the aqueous solution.  
     
     
         8 . The method of    claim 1   , wherein the guest compound is at least one compound selected from the group consisting of tetra-n-butylamnonium salts, tetra-iso-amylanonium salts, tetra-iso-butylphosphonium salts, and tri-iso-amylsulfonium salts.  
     
     
         9 . An apparatus for making a hydrant slurry comprising: 
 an apparatus for making the hydrate slurry by cooling an aqueous solution containing a guest compound to form a hydrate particles;    a heat exchanger having a heat transfer face for cooling the aqueous solution, simultaneously with the aqueous solution being circulated and cooled by contact with the heat transfer face; and,    a nuclear particle-supply mechanism for supplying a nuclear particles to the aqueous solution circulating in the heat exchanger.    
     
     
         10 . The apparatus of    claim 9   , wherein the nuclear particle-supply mechanism supplies the hydrate particles to the aqueous solution.  
     
     
         11 . The apparatus of    claim 10   , wherein the nuclear particle-supply mechanism is a hydrate particle-forming mechanism capable of being operated, independent of the heat mexchanger.  
     
     
         12 . The apparatus of    claim 10   , wherein the nuclear particle-supply m echanism has a storage vessel for storing a part of the hydrate slurry formed in the heat exchanger.  
     
     
         13 . The apparatus of    claim 9   , wherein the nuclear particle-supply mechanism has a fine article recovery tube which recovers the fine particles precipitated on a bottom of a channel for the aqueous solution and, which supplies the fine particle to the heat exchanger.  
     
     
         14 . An apparatus for making a hydrate slurry comprising: 
 an apparatus for making the hydrate slurry by cooling an aqueous solution containing a guest compound to form a hydrate particles;    a heat exchanger having a heat transfer face for cooling the aqueous solution, simultaneously with the aqueous solution being circulated and cooled by contact with the heat transfer face; and    a fine particle layer adhered to at least a part of the surface of a member in the heat exchanger in contact with the aqueous solution and acting as a nuclear of the hydrate particles.    
     
     
         15 . The apparatus of    claim 14   , wherein 
 the heat exchanger has a cylindrical heat transfer face;    a rotating blade member sliding on the heat transfer face for detaching the hydrate formed on the heat transfer face; and    the fine particle layer adheres to the surface of the rotating blade member.    
     
     
         16 . An apparatus for making a hydrate slurry comprising; 
 a means for cooling an aqueous solution containing a material for forming a clathrate hydrate as a guest compound so as to form a hydrate particles;    a means for exchanging heat between a refrigerating machine and a aqueous solution to cool the aqueous solution; and    a means for circulating the aqueous solution through the heat exchange means.    
     
     
         17 . A thermal storage method using a clathrate hydrate comprising the steps of: 
 (a) preparing an aqueous solution containing a material for forming the clathrate hydrate so that the aqueous solution has a concentration of the material which is a congruent melting point or lower; and    (b) cooling the aqueous solution to form the clathrate hydrate.    (c) achieving the thermal storage, by making use of the clathrate hydrate.    
     
     
         18 . The thermal storage method of    claim 17   , wherein the aqueous solution further contains a melting-point-lowering agent.  
     
     
         19 . The thermal storage method of    claim 17   , wherein the material for forming a clathrate hydrate is at least one compound selected from the group consisting of tetra-n-butylammonium salts, tetra-iso-amylammonium salts, tetra-n-butylphosphonium salts, and tri-iso-amylsulfonium salts.  
     
     
         20 . The thermal storage method of    claim 17   , wherein the material for forming the clathrate hydrate is tetra-n-butylammonium bromide, and the concentration of the material in the aqueous solution is 4 to 40%.  
     
     
         21 . A thermal storage apparatus using a clathrate hydrate comprising; 
 a means for storing an aqueous solution of a material for forming the clathrate hydrate, the aqueous solution having a concentration of the material which is not higher than the concentration causing the congruent melting point; and    a means for cooling the aqueous solution stored in the storing means to form a slurry of the clathrate hydrate.    
     
     
         22 . A thermal storage medium comprising an aqueous solution containing a material for forming a clathrate hydrate.  
     
     
         23 . The thermal storage medium of    claim 22   , wherein the aqueous solution has a concentration of the material which is a congruent melting point or lower.  
     
     
         24 . The thermal storage medium of    claim 22   , further comprising a melting-point-lowering agent.  
     
     
         25 . The thermal storage medium of    claim 22   , wherein the material for forming a clathrate hydrate is tetra-n-butylammonium bromide, and the concentration of the material in the aqueous solution is 4 to 40%.  
     
     
         26 . An air conditioner comprising: 
 a refrigerating machine;    a thermal storage apparatus, connected to the refrigerating machine by piping, for storing a guest compound solution forming a hydrate at a temperature higher than 0° C.;    the thermal storage apparatus comprising a heat exchanger for cooling the aqueous solution by a thermal storage medium from the refrigerating machine to form a hydrate slurry particles; and,    the thermal storage apparatus comprising a circulator for supplying the slurry to a load-side device of the air conditioner.    
     
     
         27 . The air conditioner of    claim 26   , wherein the guest compound is at least one compound selected from the group consisting of tetra-n-butylammonium salts, tetra-iso-amylammonium salts, tetra-iso-butylphosphonium salts, and tri-iso-amylsulfonium salts.  
     
     
         28 . The air conditioner of    claim 26   , wherein the refrigerating machine is an absorption refrigerating machine which forms a cooling potential by evaporation of water as a refrigerant, allows an absorbent solution to absorb the evaporated water, and concentrates the diluted absorbent solution by a heat source.  
     
     
         29 . The air conditioner of    claim 26   , wherein the refrigerating machine is a compression refrigerating machine which condenses a refrigerant by compression and forms a cooling potential by evaporation of the condensed refrigerant.