Neutralization system for electrochemical chlorine dioxide generators

Abstract

An electrochemical chlorine dioxide generator with a neutralization system includes a pH treatment tank for receiving waste products from the electrochemical generation process such as anolyte and catholyte wastes. A neutralization solution tank is fluidly connected to the pH treatment tank. A neutralization feed pump transfers a neutralization solution to the pH treatment tank. A recirculation pump for mixing the waste products is fluidly connected to the pH treatment tank. An effluent holding tank is fluidly connected to the pH treatment tank. A transfer pump transfers the neutralized waste products from the pH treatment tank to the effluent holding tank.

1 . An electrochemical chlorine dioxide generator comprising: 
 (a) an anolyte loop fluidly connected to a neutralization system; and    (b) a catholyte loop fluidly connected said neutralization system;    wherein said neutralization system neutralizes waste products from at least one of said anolyte loop and said catholyte loop.    
   
   
       2 . The electrochemical chlorine dioxide generator of  claim 1 , wherein an absorption loop is fluidly connected to said anolyte loop.  
   
   
       3 . The electrochemical chlorine dioxide generator of  claim 1 , wherein a stripper column within said anolyte loop is fluidly connected to said neutralization system.  
   
   
       4 . The electrochemical chlorine dioxide generator of  claim 1 , further comprising a pH control system to monitor the pH of said waste products in said neutralization system.  
   
   
       5 . The electrochemical chlorine dioxide generator of  claim 1 , wherein at least one of said electrochemical chlorine dioxide generator and neutralization system is controlled with a programmable logic controller.  
   
   
       6 . The electrochemical chlorine dioxide generator of  claim 1 , wherein said neutralization system comprises a pH treatment tank for receiving waste products, wherein said pH treatment tank is fluidly connected to at least one of said anolyte loop and said catholyte loop.  
   
   
       7 . The electrochemical chlorine dioxide generator of  claim 6 , wherein said neutralization system further comprises a neutralization solution tank fluidly connected to said pH treatment tank.  
   
   
       8 . The electrochemical chlorine dioxide generator of  claim 6 , further comprising a recirculation pump fluidly connected to said pH treatment tank, wherein said recirculation pump mixes said waste products in said pH treatment tank.  
   
   
       9 . The electrochemical chlorine dioxide generator of  claim 6 , further comprising an effluent holding tank fluidly connected to said pH treatment tank, wherein said effluent holding tank receives neutralized waste products.  
   
   
       10 . The electrochemical chlorine dioxide generator of  claim 9 , further comprising a transfer pump for transferring said neutralized waste products to said effluent holding tank, wherein a diverting valve controls said fluid connection between said pH treatment tank and said effluent holding tank.  
   
   
       11 . The electrochemical chlorine dioxide generator of  claim 7 , wherein an acidic solution contained in said neutralization solution tank is used to neutralize said waste products in said pH treatment tank.  
   
   
       12 . The electrochemical chlorine dioxide solution generator of  claim 11 , wherein said acidic solution comprises hydrochloric acid.  
   
   
       13 . The electrochemical chlorine dioxide generator of  claim 11 , wherein said acidic solution further comprises a chlorite neutralizing compound.  
   
   
       14 . The electrochemical chlorine dioxide generator of  claim 13 , wherein said chlorite neutralizing compound is selected from the group of ferrous chloride tetra hydrate, sodium sulfite, sodium metabisulfite, and sodium thiosulfate pentahydrate.  
   
   
       15 . An electrochemical chlorine dioxide generator with a neutralization system comprising: 
 (a) a pH treatment tank for receiving waste products from said electrochemical generator;    (b) a neutralization solution tank fluidly connected to said pH treatment tank, wherein a neutralization feed pump transfers a neutralization solution to said pH treatment tank;    (c) a recirculation pump fluidly connected to said pH treatment tank, wherein said recirculation pump mixes said waste products in said pH treatment tank;    (d) an effluent holding tank fluidly connected to said pH treatment tank; and    (e) a transfer pump for transferring neutralized waste products from said pH treatment tank to said effluent holding tank.    
   
   
       16 . The electrochemical chlorine dioxide generator of  claim 15 , wherein said neutralization solution is an acidic solution.  
   
   
       17 . The electrochemical chlorine dioxide generator of  claim 18 , wherein said acidic solution further comprises a chlorite neutralizing compound.  
   
   
       18 . The electrochemical chlorine dioxide generator of  claim 13 , wherein said chlorite neutralizing compound is selected from the group of ferrous chloride tetra hydrate, sodium sulfite, sodium metabisulfite, and sodium thiosulfate pentahydrate.  
   
   
       19 . A method for neutralizing waste products from an electrochemical chlorine dioxide generator comprising: 
 (a) collecting waste products from said electrochemical generator in a pH treatment tank;    (b) adding a neutralizing solution to said waste product in said pH treatment tank;    (c) recirculating said waste products to achieve at least one of the removal of substantially all chlorite and a pH between 4 and 10; and    (d) transferring said waste products from said pH treatment tank to an effluent holding tank.    
   
   
       20 . The method of  claim 19 , further comprising controlling said neutralizing of waste products with a programmable logic controller.