Corrosion inhibitors for use in oil and gas wells and similar applications

Abstract

Anti-corrosion additives and processes useful for oil drilling and similar applications. Heteropoly complex anions of transitional metal elements can be added to an oil well drilling solution which includes a metallic salt, optionally in combination with transition metal compounds or compounds of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements, to minimize corrosion of systems within which the solution is used.

That which is claimed is:  
     
         1 . A solution having corrosion inhibiting properties useful in oil and gas well drilling systems and similar applications, the solution comprising: 
 an aqueous solution comprising at least one transition metal salt, at least one alkaline earth metal salt, or a mixture thereof; and    at least one heteropoly complex anion of a transition metal element present in an amount sufficient to provide a corrosion inhibiting effect.    
     
     
         2 . The solution of  claim 1 , wherein said transition metal salt comprises one or more zinc halides.  
     
     
         3 . The solution of  claim 1 , wherein said alkaline earth metal salt comprises one or more calcium halides.  
     
     
         4 . The solution of  claim 1 , wherein said solution comprises at least one zinc halide and at least one calcium halide.  
     
     
         5 . The solution of  claim 4 , wherein said solution comprises zinc bromide, optionally zinc chloride, calcium bromide, and optionally calcium chloride.  
     
     
         6 . The solution of  claim 1 , said solution further comprising at least one additional corrosion inhibiting additive in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         7 . The solution of  claim 1 , wherein said at least one heteropoly complex anion comprises a compound selected from the group consisting of [X a M b O c ] −n , [X a Z d M b O c ] −n , [X a Z d M b O c He] −n , [X a M b O c (OH) f ] −n , [X a Z d M b O c (OH) f ] −n , and mixtures thereof, wherein: 
 X and Z are central heteroatoms selected from the group consisting of elements from Groups I-VIII of the Periodic Table of Elements;    a is 1 or 2;    d is an integer from 0 to 4;    M b O c , M b O c H e , and M b O c (OH) f  are oxoanions in which M is a transition metal element; b is an integer from 5 to 22; c is an integer from 20 to 70; e is an integer from 0 to 6; and f is an integer from 0 to 3; and    n is the charge of the anion.    
     
     
         8 . The solution of  claim 7 , wherein: 
 X is phosphorus, silicon, manganese, tellurium or arsenic; and    M is molybdenum or tungsten.    
     
     
         9 . The solution of  claim 1 , wherein said at least one heteropoly complex anion is selected from the group consisting of phosphomolybdates, silicon molybdates, manganese molybdates, silicon tungstates, tellurium molybdates, arsenic molybdates, and mixtures thereof.  
     
     
         10 . The solution of  claim 1 , wherein said at least one heteropoly complex anion comprises a phosphomolybdate of the formula [PMo 12 O 40 ] −3 .  
     
     
         11 . The solution of  claim 6 , wherein said additional corrosion inhibiting additive comprises at least one transition metal compound which is different from said transition metal salt and from said heteropoly complex anion of a transition metal element.  
     
     
         12 . The solution of  claim 11 , wherein said additional corrosion inhibiting additive comprises a transition metal which is different from the transition metal of the heteropoly complex anion.  
     
     
         13 . The solution of  claim 11 , wherein said additional corrosion inhibiting additive is selected from the group consisting of nitrates, halides, and oxides of transition metal elements, and mixtures thereof.  
     
     
         14 . The solution of  claim 13 , wherein said transition metal is selected from the group consisting of cobalt, nickel, tungsten, zirconium, manganese, chromium, and mixtures thereof.  
     
     
         15 . The solution of  claim 6 , wherein said additional corrosion inhibiting additive comprises at least one compound of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements.  
     
     
         16 . The solution of  claim 15 , wherein said additional corrosion inhibiting additive is selected from the group consisting of oxides, sulfides, halides, nitrates, and mixtures thereof of metallic elements of Group IIIa to VIa.  
     
     
         17 . The solution of  claim 16 , wherein said additional corrosion inhibiting additive is a halide of a metallic element of Groups IIIa to VIa.  
     
     
         18 . The solution of  claim 17 , wherein said halide is selected from the group consisting of antimony bromide, germanium bromide, arsenic bromide, and bismuth bromide, and mixtures thereof.  
     
     
         19 . The solution of  claim 15 , wherein said additional corrosion inhibiting additive comprises antimony as the metallic element of Groups IIIa to VIa.  
     
     
         20 . The solution of  claim 1 , wherein said solution comprises said transition metal salt, said alkaline earth metal salt or mixture thereof in an amount from about 1 to about 80 weight percent, based on the total weight of the solution.  
     
     
         21 . The solution of  claim 20 , wherein said solution comprises said transition metal salt, said alkaline earth metal salt or mixture thereof in an amount from about 20 to about 60 weight percent, based on the total weight of the solution.  
     
     
         22 . A solution having corrosion inhibiting properties useful in oil and gas well drilling systems and similar applications, the solution comprising: 
 at least one salt selected from the group consisting of first transition metal salts, alkaline earth metal salts, and mixtures thereof;    at least one heteropoly complex anion of a transition metal element; and    at least one additional corrosion inhibiting agent selected from the group consisting of transition metal salts which are different from said first transition metal salts, salts of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements, and mixtures thereof,    said heteropoly complex anion and said additional additive present in an amount sufficient to provide a corrosion inhibiting effect.    
     
     
         23 . The solution of  claim 22 , wherein said first transition metal salt comprises one or more zinc halides.  
     
     
         24 . The solution of  claim 22 , wherein said alkaline earth metal salt comprises one or more calcium halides.  
     
     
         25 . The solution of  claim 22 , wherein said solution comprises at least one zinc halide and at least one calcium halide.  
     
     
         26 . The solution of  claim 25 , wherein said solution comprises zinc bromide, optionally zinc chloride, calcium bromide, and optionally calcium chloride.  
     
     
         27 . The solution of  claim 22 , wherein said heteropoly complex anion comprises a phosphomolybdate, and said additional additive comprises at least one transition metal salt.  
     
     
         28 . The solution of  claim 27 , wherein said additional additive comprises at least one halide of cobalt, nickel, tungsten, zirconium, manganese, chromium, and mixtures thereof.  
     
     
         29 . The solution of  claim 22 , wherein said heteropoly complex anion comprises a phosphomolybdate and said additional additive comprises at least one salt of a metallic element of Group IIIa to VIa.  
     
     
         30 . The solution of  claim 29 , wherein said additional additive comprises a halide of the metallic elements of Group Va of the Periodic Table of Elements.  
     
     
         31 . The solution of  claim 30 , wherein said additional additive comprises a compound selected from the group consisting of antimony bromide (SbBr 3 ), arsenic bromide, bismuth bromide and mixtures thereof.  
     
     
         32 . The solution of  claim 22 , wherein said heteropoly complex anion is [PMo 12 O 40]   −3 .  
     
     
         33 . The solution of  claim 22 , wherein said first transition metal salts, alkaline earth metal salts, and mixtures thereof are present in an amount from about 20 to about 60 weight percent, based on the total weight of the solution.  
     
     
         34 . An aqueous completion fluid for oil and gas well drilling systems having corrosion inhibiting properties, comprising at least one zinc halide, at least one calcium halide, or a mixture thereof; at least one phosphomolybdate; and at least one halide of the metallic elements of Group Va of the Periodic Table of Elements, said phosphomolybdate and said Group Va halide present in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         35 . The aqueous completion fluid of  claim 34 , wherein said phosphomolybdate is [PMo 12 O 40 ] −3 , and said Group Va halide is antimony bromide (SbBr 3 ).  
     
     
         36 . The aqueous completion fluid of  claim 35 , wherein said solution comprises zinc bromide, optionally zinc chloride, calcium bromide, and optionally calcium chloride.  
     
     
         37 . A solution having corrosion inhibiting properties useful in oil and gas well drilling systems and similar applications, the solution comprising: 
 an aqueous solution comprising at least one transition metal salt, at least one alkaline earth metal salt, or a mixture thereof; and    at least one corrosion inhibiting agent comprising at least one compound of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements.    
     
     
         38 . The solution of  claim 37 , wherein said transition metal salt comprises one or more zinc halides.  
     
     
         39 . The solution of  claim 37 , wherein said alkaline earth metal salt comprises one or more calcium halides.  
     
     
         40 . The solution of  claim 37 , wherein said solution comprises at least one zinc halide and at least one calcium halide.  
     
     
         41 . The solution of  claim 40 , wherein said solution comprises zinc bromide, optionally zinc chloride, calcium bromide, and optionally calcium chloride.  
     
     
         42 . The solution of  claim 37 , wherein said corrosion inhibiting agent is selected from the group consisting of oxides, sulfides, halides, nitrates, and mixtures thereof of metallic elements of Group IIIa to VIa.  
     
     
         43 . The solution of  claim 42 , wherein said corrosion inhibiting agent is a halide of a metallic element of Groups IIIa to VIa.  
     
     
         44 . The solution of  claim 43 , wherein said corrosion inhibiting agent comprises antimony.  
     
     
         45 . The solution of  claim 37 , wherein said corrosion inhibiting agent comprises at least one compound selected from the group consisting of antimony bromide, germanium bromide, arsenic bromide, and bismuth bromide, and mixtures thereof.  
     
     
         46 . A solution having corrosion inhibiting properties useful in oil and gas well drilling systems and similar applications, the solution comprising at least one zinc halide, at least one calcium halide, or a mixture thereof; and at least one halide of the metallic elements of Group Va of the Periodic Table of Elements in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         47 . The solution of  claim 46 , wherein said Group Va halide is antimony bromide (SbBr 3 ).  
     
     
         48 . The solution of  claim 47 , wherein said solution comprises zinc bromide, optionally zinc chloride, calcium bromide, and optionally calcium chloride.  
     
     
         49 . A process for inhibiting the corrosion of metal surfaces in oil and gas well drilling systems and similar systems employing an aqueous completion fluid, the process comprising contacting the metal surfaces with at least one heteropoly complex anion of a transition metal element in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         50 . The process of  claim 49 , further comprising contacting said metal surfaces with at least one additional additive having corrosion inhibiting properties in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         51 . The process of  claim 50 , wherein said additional additive comprising a compound selected from the group consisting of transition metal compounds, compounds of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements, and mixtures thereof.  
     
     
         52 . The process of  claim 49 , wherein said at least one heteropoly complex anion comprises a compound selected from the group consisting of [X a M b O c ] −n , [X a Z d M b O c ] −n , [X a Z d M b O c H e ] −n , [X a M b O c (OH) f ] −n , [X a Z d M b O c (OH) f ] −n , and mixtures thereof, wherein: 
 X and Z are central heteroatoms selected from the group consisting of elements from Groups I-VIII of the Periodic Table of Elements;    a is 1 or 2;    d is an integer from 0 to 4;    M b O c , M b O c H e , and M b O c (OH) f  are oxoanions in which M is a transition metal element; b is an integer from 5 to 22; c is an integer from 20 to 70; e is an integer from 0 to 6; and f is an integer from 0 to 3; and    n is the charge of the anion.    
     
     
         53 . The process of  claim 52 , wherein: 
 X is phosphorus, silicon, manganese, tellurium or arsenic; and    M is molybdenum or tungsten.    
     
     
         54 . The process of  claim 49 , wherein said at least one heteropoly complex anion is selected from the group consisting of phosphomolybdates, silicon molybdates, manganese molybdates, silicon tungstates, tellurium molybdates, arsenic molybdates, and mixtures thereof.  
     
     
         55 . The process of  claim 49 , wherein said at least one heteropoly complex anion comprises a phosphomolybdate of the formula [PMo 12 O 40 ] −3 .  
     
     
         56 . The process of  claim 50 , wherein said additional corrosion inhibiting additive is selected from the group consisting of nitrates, halides, and oxides of transition metal elements, and mixtures thereof.  
     
     
         57 . The process of  claim 56 , wherein said transition metal is selected from the group consisting of cobalt, nickel, tungsten, zirconium, manganese, chromium, and mixtures thereof.  
     
     
         58 . The process of  claim 57 , wherein said additional corrosion inhibiting additive is a transition metal halide.  
     
     
         59 . The process of  claim 50 , wherein said at least one additional corrosion inhibiting additive comprises at least one compound of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements.  
     
     
         60 . The process of  claim 59 , wherein said additional corrosion inhibiting additive is selected from the group consisting of oxides, sulfides, halides, nitrates, and mixtures thereof of metallic elements of Group IIIa to VIa.  
     
     
         61 . The process of  claim 60 , wherein said additional corrosion inhibiting additive is a halide.  
     
     
         62 . The process of  claim 61 , wherein said halide is selected from the group consisting of antimony bromide, germanium bromide, arsenic bromide, and bismuth bromide, and mixtures thereof.  
     
     
         63 . The process of  claim 62 , wherein said halide is antimony halide.  
     
     
         64 . The process of  claim 49 , wherein said at least one heteropoly complex anion forms a protective layer on a metal surface.  
     
     
         65 . The process of  claim 49 , wherein said metal surfaces are exposed to temperatures up to about 550° F.  
     
     
         66 . A process for inhibiting the corrosion of metal surfaces in oil and gas well drilling systems and similar systems employing an aqueous completion fluid, the process comprising contacting the metal surfaces with at least one at least one compound of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         67 . The process of  claim 66 , wherein said compound is selected from the group consisting of oxides, sulfides, halides, nitrates, and mixtures thereof of metallic elements of Group IIIa to VIa.  
     
     
         68 . The process of  claim 67 , wherein said compound is a halide.  
     
     
         69 . The process of  claim 68 , wherein said compound comprises antimony.  
     
     
         70 . The process of  claim 66 , wherein said compound of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements forms a protective layer on a metal surface.  
     
     
         71 . The process of  claim 66 , wherein said metal surfaces are exposed to temperatures up to about 550° F.  
     
     
         72 . A process for inhibiting the corrosion of metal surfaces in oil and gas well drilling systems and similar systems employing an aqueous completion fluid, the process comprising providing in a oil or gas well drilling system a corrosion inhibiting solution comprising at least one metallic salt and at least one heteropoly complex anion of a transition metal element, said at least one heteropoly complex anion of a transition metal element present in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         73 . The process of  claim 72 , wherein said solution further comprises at least one additional corrosion inhibiting additive comprising a compound selected from the group consisting of transition metal compounds, compounds of the metallic elements of Groups IIIa to VIa of the Periodic Table of Elements, and mixtures thereof, said at least one additional additive present in an amount sufficient to provide a corrosion inhibiting effect.  
     
     
         74 . The process of  claim 72 , wherein said at least one heteropoly complex anion forms a protective layer on a metal surface.  
     
     
         75 . The process of  claim 72 , wherein said solution is exposed to temperatures up to about 550° F.  
     
     
         76 . The process of  claim 72 , wherein said solution further comprises lithium nitrate and zinc halide.