Process for reducing bio-corrosion in water systems

Abstract

Bacterial contamination of industrial water systems lead to bacterial induced corrosion. This invention provides a method for control of corrosion of industrial water systems caused by bacteria by the destruction of targeted problematic bacteria with naturally occurring, non-engineered bacteriophage virulent for targeted bacteria. The invention also provides a staged sequencing of control to adapt to changing conditions.

1 . A process for reducing bio-corrosion in an industrial water system containing a multiplicity of target bacteria comprising:
 culturing a dominant group of bacteria in a mixed bacteria solution, isolating virulent phage(s) for the dominate a bacteria, lysing dominant bacteria from a sample of the mixed bacteria solution to remove the dominant bacteria from the mix;   culturing the next dominant strain from the solution with the dominate strain lysed, isolating a virulent phage for the next dominate bacteria, lysing it to remove the next dominate bacteria; and   continuing the sequence to provide a set of bacteriophage that will lyse the dominate and sub-dominate bacteria;   applying an effective amount of the bacteriophage so isolated in each step either as a mixture or in sequence application to the water system containing a mixture of target bacteria of those found in each step of the above sequence.   
     
     
         2 . The process of  claim 1  wherein target bacteria(s) comprise sulfate reducing bacteria, sulfur-oxidizing bacteria capable of generating sulfuric acid, and iron-oxidizing bacteria. 
     
     
         3 . The process of  claim 1  comprising the culturing of bacteria in the sequence is conducted at simulated conditions substantially approximating the conditions of use of or collection of the virulent phage. 
     
     
         4 . The process of  claim 1  wherein of the simulated conditions comprise temperature, oxygen level and salinity. 
     
     
         5 . A process for reduction of bio-corrosion in an industrial water system containing a multiplicity of target bacteria containing a multiplicity of target bacteria comprising:
 culturing a dominant group of bacteria from a diverse mixture of target bacteria, isolating virulent phage active against the dominant bacteria;   isolation of temperate phages from these bacterial strains from the culture supernatant; stressing the temperate bacteria to convert into virulent phages for use in phage preparations;   continuing the sequence until a collection of phage is assembled that will effect significant and lasting of problematic bacteria; and   applying an effective amount of the phage so isolated in each step either as a mixture or in sequence application to waters containing the a mixture of target bacteria of those found in each step of the above sequence.   
     
     
         6 . The process of  claim 5  wherein the temperate bacteria so isolated are stressed by application of an appropriate amount of ultra-violet light, heat, antibiotics or chemicals that are toxic to the bacteria. 
     
     
         7 . The process of  claim 1  wherein target bacteria(s) comprise sulfate reducing bacteria, sulfur-oxidizing bacteria capable of generating sulfuric acid, and iron-oxidizing bacteria. 
     
     
         8 . The process of  claim 5  wherein the predominant bacteria in the mixed bacteria solution are sulfate reducing bacteria of the species  Desulfovibrios.