Method for burning wastes almost without generating dioxin, inhibitor of generating dioxin, and method of producing the inhibitor

Abstract

The invention provides a technology to largely decrease generation of dioxin in combustion ashes as well as exhaust gas by use of an ordinary combustion apparatus. The invention spreads over wastes being burnt an inhibitor for inhibiting generation of dioxin that comprises as main contents an adsorbing substance superior in rate of adsorbing hydrogen chloride gas and a reaction substance superior in reactivity with hydrogen chloride gas, and additionally a degradation agent when required, those mixed, granulated and dried, whereby a powder material removes hydrogen chloride gas in combustion gas and flying ashes and a granular material removes hydrogen chloride gas in residual ashes, thereby inhibiting generation of dioxin.

What we claimed is:  
     
         1 . A method for burning wastes almost without generating dioxin comprising 
 spreading over wastes being burnt    a mixture of a granular material and a powder material that comprise as main contents an adsorbing substance superior in rate of adsorbing hydrogen chloride gas and a reaction substance superior in reactivity with hydrogen chloride gas, or a granular material comprising as the main contents the adsorbing substance and the reaction substance and partly easily degradable into a powder material by a mechanical or thermal stimulation,    whereby the powder material removes hydrogen chloride gas in combustion gas, exhaust gas and flying ashes and the granular material removes hydrogen chloride gas generated upon burning wastes and hydrogen chloride gas in residual ashes, thereby inhibiting generation of dioxin.    
     
     
         2 . A method for burning wastes almost without generating dioxin comprising press feeding to a combustion point of wastes being burnt a powder material that comprises as main contents an adsorbing substance superior in rate of adsorbing hydrogen chloride gas and a reaction substance superior in reactivity with hydrogen chloride gas, whereby removing hydrogen chloride gas generated upon burning wastes and inhibiting generation of dioxin.  
     
     
         3 . A method for burning wastes almost without generating dioxin comprising previously mixing with wastes before burning operation 
 a granular material and/or a powder material that comprise as main contents an adsorbing substance superior in rate of adsorbing hydrogen chloride gas and a reaction substance superior in reactivity with hydrogen chloride gas,    whereby removing hydrogen chloride gas in combustion gas, exhaust gas, flying ashes and residual ashes and inhibiting generation of dioxin.    
     
     
         4 . A method for burning wastes almost without generating dioxin as set forth in  claim 1 ,  2  or  3 , wherein the adsorbing substance employs synthetic zeolite, fly ash, coffee grounds, used tea leaves or other wastes of plant, or any of these being activated, and the reaction substance employs at least one compound among calcium oxide and calcium hydroxide.  
     
     
         5 . A method for burning wastes almost without generating dioxin as set forth in  claim 1  or  3 , wherein spreading over wastes being burnt at more than 450° C. an inhibitor for inhibiting generation of dioxin that comprises as main matters at least one compound among calcium oxide and calcium hydroxide and powder of an adsorbing substance superior in rate of adsorbing hydrogen chloride gas, such as synthetic zeolite, fly ash, coffee grounds, used tea leaves, other wastes of plant or any of these being activated, and additionally, a degradation agent, those materials being into granules and dried, 
 whereby causing the inhibitor to be partly degraded into a powder material.  
 
     
     
         6 . A method for burning wastes almost without generating dioxin as set forth in  claim 1 ,  2 ,  3 ,  4  or  5  wherein the dioxin-generation inhibitor is spread over wastes to be burnt at a proportion of 0.2 to 5 wt % or preferably of 0.5 to 1.5 wt % with respect to a weight of wastes when in dry state.  
     
     
         7 . An inhibitor for inhibiting generation of dioxin comprising a mixture of a granular material and a powder material that composed of as main contents an adsorbing substance superior in rate of adsorbing hydrogen chloride gas and a reaction substance superior in reactivity with hydrogen chloride gas, or a granular material comprising as the main contents the adsorbing substance and the reaction substance and partly easily degradable into a powder material by a mechanical or thermal stimulation.  
     
     
         8 . An inhibitor for inhibiting generation of dioxin as set forth in  claim 7  wherein the adsorbing substance employs synthetic zeolite, fly ash, coffee grounds, used tea leaves or other wastes of plant, or any of these being activated, and the reaction substance employs at least one compound among calcium oxide and calcium hydroxide.  
     
     
         9 . An inhibitor for inhibiting generation of dioxin as set forth in  claim 7  or  8  wherein an organic matter or oyster shell powder as the degradation agent is added and the mixed materials are granulated and dried.  
     
     
         10 . A method of producing a dioxin-generation inhibitor comprising the steps of mixing a powder of an adsorbing substance superior in rate of adsorbing hydrogen chloride gas, such as synthetic zeolite, fly ash, coffee grounds, used tea leaves, other wastes of plant or any of these being activated, and a powder of at least one compound among calcium oxide and calcium hydroxide, and adding a little amount of powder of an organic matter or oyster shell as a degradation agent when required, and then granulating and drying these mixed materials.  
     
     
         11 . A method of producing a dioxin-generation inhibitor as set forth in  claim 10  wherein the granules material after drying is subjected to a granulator to be partly made powdery.  
     
     
         12 . A method of producing a RDF having less generation of dioxin comprising a process of adding to crushed wastes when crushed, compressed and made solid a mixture of a powder of an adsorbing substance superior in rate of adsorbing hydrogen chloride gas, such as synthetic zeolite, fly ash, coffee grounds, used tea leaves, other wastes of plant or any of these being activated, and a powder of at least one compound among calcium oxide and calcium hydroxide.  
     
     
         13 . A method of producing a RDF having less generation of dioxin as set forth in  claim 12  wherein the powder mixture is added at a proportion of 0.2 to 5 wt %, preferably 0.5 to 1.5 wt % with respect to a weight of wastes being dry.