Remediation of heavy metals in ammunition traps and shooting ranges

Abstract

The invention provides methods of remediating lead and other heavy metals in ammunition traps and shooting ranges. One or more remediation agents is added to a trap or a shooting range. The remediation agent(s) interact with and “fix” heavy metals, rendering them substantially non-leachable. An improved ammunition trap is also provided.

1 . A method of remediating a heavy metal in an ammunition trap, comprising: adding to the trap at least one heavy metal remediation agent.  
   
   
       2 . A method as recited in  claim 1 , wherein the at least one remediation agent is selected from the group consisting of calcium sulfide, calcium phosphate, calcium hydroxide, calcium oxide, calcium carbonate, magnesium sulfide, magnesium phosphate, magnesium hydroxide, magnesium oxide, magnesium carbonate, apatite, di-calcium hydrogen phosphate, calcium di-hydrogen phosphate, triple super phosphate, dolomite, phosphoric acid, mixed calcium adducts thereof, phosphoric acid and its salts, alkaline earth silicates, hydrated silica, hydrated alumina, metal-sorbing clays, and mixtures thereof.  
   
   
       3 . A method as recited in  claim 1 , wherein the at least one remediation agent comprises a mixture of calcium sulfide, calcium carbonate, and calcium phosphate or triple super phosphate.  
   
   
       4 . A method as recited in  claim 1 , wherein the at least one remediation agent comprises a 3:2:1 (wt/wt) mixture of calcium carbonate, calcium sulfide, and triple super phosphate.  
   
   
       5 . A method as recited in  claim 1 , wherein the at least one remediation agent agents is added to the trap as a block or pellet, a flake, a free-flowing powder, or a slurry.  
   
   
       6 . A method of remediating a heavy metal in an ammunition trap, comprising: adding to the trap a block comprising at least one remediation agent dispersed in a binder.  
   
   
       7 . A method as recited in  claim 6 , wherein the at least one remediation agent is selected from the group consisting of calcium sulfide, calcium phosphate, calcium hydroxide, calcium oxide, calcium carbonate, magnesium sulfide, magnesium phosphate, magnesium hydroxide, magnesium oxide, magnesium carbonate, apatite, di-calcium hydrogen phosphate, calcium di-hydrogen phosphate, triple super phosphate, dolomite, phosphoric acid, mixed calcium adducts thereof, phosphoric acid and its salts, alkaline earth silicates, hydrated silica, hydrated alumina, metal-sorbing clays, and mixtures thereof.  
   
   
       8 . A method as recited in  claim 6 , wherein the at least one remediation agent comprises a mixture of calcium sulfide, calcium carbonate, and calcium phosphate or triple super phosphate.  
   
   
       9 . method as recited in  claim 6 , wherein the binder comprises a water-soluble and/or water-degradable wax.  
   
   
       10 . A method as recited in  claim 9 , wherein the water-soluble and/or water-degradable wax is selected from the group consisting of hydratable and/or degradable polyethylene glycols, copolymers of ethylene glycol, and mixtures thereof.  
   
   
       11 . A method as recited in  claim 6 , wherein the binder is selected from the group consisting of polyacrylates, hydratable cellulose compounds, methyl, ethyl, propyl and/or butyl ethers of hydratable cellulose compounds, and mixtures thereof.  
   
   
       12 . A method as recited in  claim 6 , wherein the block further comprises one or more surfactants, dispersing aids, and/or flocculating agents.  
   
   
       13 . A method as recited in  claim 12 , wherein the block contains at least one compound selected from the group consisting of polyethoxyethylene ethers of fatty acids, polyethoxyethylene esters of fatty acids, and polyethoxy ethers of alcohols (e.g., polyether alcohols having the formula CH 3 (CH 2 ) x —O—(CH 2 CH 2 ) y —OH, where x > or =5 and y>1.  
   
   
       14 . A method for making a heavy metal remediation block or pellet, comprising: 
 at least one heavy metal remediation agent and dispersed 
 forming a mixture of at least one remediation agent and a water-soluble or water soluble binder;  
 heating the mixture to form a melt; and  
 casting the melt into a pellet or block.  
   
   
   
       15 . A method as recited in  claim 14 , wherein the mixture further comprises one or more surfactants, dispersing aids, and/or flocculating agents.  
   
   
       16 . A heavy metal remediation block or pellet, comprising: 
 at least one heavy metal remediation agent and one or more surfactants, dispersing aids, and/or flocculating agents, dispersed in a water-soluble or water degradable binder.    
   
   
       17 . A method of remediating a shooting range contaminated with at least one heavy metal, comprising: introducing one or more remediation agents into a drainage system of the shooting range.  
   
   
       18 . A method of remediating an outdoor shooting range contaminated with at least one heavy metal, comprising: allowing one or more remediation agents to contact the shooting range.  
   
   
       19 . An improved ammunition trap, comprising: at least one heavy metal remediation agent in combination with an ammunition trap.  
   
   
       20 . An improved ammunition trap, comprising at least one ammunition impact-absorbing and/or deflection means; a receptacle for spent ammunition, fragments, fines, and/or dust; and at least one remediation agent in the receptacle.  
   
   
       21 . In a bullet trap having a box and an impact-absorbing material, the improvement comprising a heavy metal remediation agent inside the box.