PROCESS FOR REDUCING BIO-CORROSION IN WATER SYSTEMS
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.