Anti-oxidizing process for non-cryogenic nitrogen

Abstract

Downhole equipment oxidation and injection well plugging consequential of non-cryogenic nitrogen utilities is prevented or alleviated by injecting a residual oxygen scavenging compound such as ammonium bisulfite into the predominately nitrogen and residual oxygen flow stream emerging from a non-cryogenic nitrogen concentration process.

1 . A conditioning process for a subterranean well utility gas containing free oxygen, said process comprising the step of mixing an oxygen scavenging compound with said utility gas prior to well injection.  
   
   
       2 . A well utility gas conditioning process as described by  claim 1  wherein said oxygen scavenging compound is selected from the group comprising ammonium bisulfite.  
   
   
       3 . A well utility gas conditioning process as described by  claim 1  wherein said oxygen scavenging compound is selected from the group comprising ammonium bisulfite solution, ammonium hydrogen sulfite solution, ammonium acid sulfite solution, monoammonium sulfite solution and sulfurous acid monoammonium salt solution.  
   
   
       4 . A process for extracting fluid from a subterranean well comprising the steps of: 
 a. generating a flow stream of non-cryogenic nitrogen containing residual quantities of oxygen.    b. mixing an oxygen scavenger compound with said flow stream;    c. injecting the mixed flow stream comprising non-cryogenic nitrogen and oxygen scavenger into a subterranean well;    d. recovering fluids extracted from said well; and    e. separating said extracted well fluids by phase and gravity.    
   
   
       5 . A process for extracting fluid from a subterranean well as described by  claim 4  wherein said oxygen scavenging compound is selected from the group comprising ammonium bisulfite.  
   
   
       6 . A process for extracting fluid from a subterranean well as described by  claim 4  wherein said oxygen scavenging compound is selected from the group comprising ammonium bisulfite solution, ammonium hydrogen sulfite solution, ammonium acid sulfite solution, monoammonium sulfite solution and sulfurous acid monoammonium salt solution.  
   
   
       7 . A process for extracting fluid from a subterranean well as described by  claim 4  wherein portions of separated fluid containing water are returned to a subterranean formation  
   
   
       8 . A process for conditioning a non-cryogenic nitrogen drilling fluid containing residual oxygen, said process comprising the step of mixing an oxygen scavenging compound with said drilling fluid.  
   
   
       9 . A process as described by  claim 8  wherein said oxygen scavenging compound is selected from the group comprising ammonium bisulfite.  
   
   
       10 . A process as described by  claim 8  wherein said oxygen scavenging compound is selected from the group comprising ammonium bisulfite solution, ammonium hydrogen sulfite solution, ammonium acid sulfite solution, monoammonium sulfite solution and sulfurous acid monoammonium salt solution.  
   
   
       11 . An apparatus for supplying utility gas to a subterranean well, said apparatus comprising: 
 a. a first compressor of atmospheric air having a first discharge flow stream;    b. a semi-permeable membrane bundle receiving said first discharge flow stream for substantial separation of oxygen from said atmospheric air, said membrane having a second discharge flow stream substantially comprising nitrogen mixed with a substantially reduced quantity of oxygen;    c. a second compressor receiving said second discharge flow stream and discharging a third flow stream;    d. a proportional mixing valve receiving said third flow stream and a forth flow stream comprising an oxygen scavenging compound for generating a fifth discharge flow stream, said mixing valve combining said oxygen scavenging compound with said third flow stream at a rate sufficient to substantially preempt the reactive potential of residual oxygen in said third flow stream; and,    e. utilizing said fifth discharge flow stream in a subterranean well development.    
   
   
       12 . An apparatus as described by  claim 11  wherein said subterranean well development is a well drilling operation.  
   
   
       13 . An apparatus as described by  claim 11  wherein said subterranean well development is a well fluid extraction operation.  
   
   
       14 . An apparatus as described by  claim 11  wherein said oxygen scavenging compound is ammonium bisulfite.  
   
   
       15 . An apparatus as described by  claim 11  wherein said oxygen scavenging compound is selected from the group comprising ammonium bisulfite.  
   
   
       16 . An apparatus as described by  claim 11  wherein said oxygen scavenging compound is selected fro the group comprising ammonium bisulfite solution, ammonium hydrogen sulfite solution, ammonium acid sulfite solution, monoammonium sulfite solution and sulfurous acid monoammonium salt solution.