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Picture for Enhanced Biocide Treatment Using D-tyrosine Against Desulfovibrio Vulgaris Corrosion of Carbon Steel
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Enhanced Biocide Treatment Using D-tyrosine Against Desulfovibrio Vulgaris Corrosion of Carbon Steel

Product Number: 51320-14527-SG
Author: Tuba Unsal, Di Wang, Tingyue Gu, Sith Kumseranee, Suchada Punpruk
Publication Date: 2020
$20.00
Picture for Microbiologically Influenced Corrosion by General Aerobic and Anaerobic Bacteria in Oil & Gas Separators
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Microbiologically Influenced Corrosion by General Aerobic and Anaerobic Bacteria in Oil & Gas Separators

Product Number: 51320-14365-SG
Author: Amer Jarragh, Saleh Al-Sulaiman, Yousef Khuraibut, Hasan Bu Taleb, Dr. Ali Moosavi
Publication Date: 2020
$20.00

By far, the microbiological species most associated with corrosion has been Sulphate-Reducing Bacteria (SRB).  Majority of Microbiologically Influenced Corrosion (MIC) research has focused on the activities of this type of bacteria. One of the primary reasons for this has been the presence of iron sulfides in corrosion products associated with MIC. SRB reduce sulfates to sulfides, which then react with iron and steel. However, an accepted fact is that MIC is also caused by the action of the biofilm produced by bacteria, in a similar way to under-deposit corrosion. 

The primary method used to prevent MIC in the oil and gas industry is by use of biocides. The criteria used for selection of biocides is often their proficiency to kill SRB. The danger with this is that one can neglect the ability of other bacteria frequently found in oil and gas environment, such as general aerobes and general anaerobes to cause corrosion by biofilm production. This became evident when severe general & pitting corrosion was observed in two oil and gas separators in one of the facilities in Kuwait Oil Company (KOC), where SRB levels were zero but significant numbers of sessile and planktonic general aerobes and general anaerobes were found to be present in the process. 

Using microbiological and chemical analysis, the mechanism of this type of MIC, specially the relationship between the quantity of various biofilm-forming bacteria and nature and magnitude of corrosion has been studied and the findings are presented in this paper. 

Picture for Remediation of Microbially Contaminated Horizontal Wells with Acrolein
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Remediation of Microbially Contaminated Horizontal Wells with Acrolein

Product Number: 51320-14992-SG
Author: Jodi B. Wrangham, Adam Bounds, Jerry L. Conaway, Jim Ott, Mason Long, and Corey Stevens
Publication Date: 2020
$20.00

The lengthy laterals of horizontal wells often pose microbiological challenges, as they provide more area to become microbially contaminated and require larger volumes of fluid and biocide for treatment. A Permian Basin oilfield has been experiencing MIC-related failures in its horizontal wells, which is of concern due to the associated high workover cost.   

Laboratory biocide challenge testing identified several common oilfield chemistries and combinations thereof as being effective against this field’s population of microbes.  However, aggressive applications of these products in the field neither delivered an effective microbial kill nor prevented the treated wells from experiencing further MIC and failures. 

An acrolein field trial was conducted on a set of problematic, microbially contaminated horizontal wells over a time period of approximately one year.  During this timeframe, these wells experienced microbial control for the first time, defined as meeting and maintaining microbial KPIs.  Additional benefits were realized as a result of acrolein, including a dramatic improvement in water quality evident as a decrease in iron sulfide and suspended solids, a clean-out of the wells inferred by an initial increase of solids post-acrolein, a decrease in the corrosion rate as indicated by a significant reduction in iron and manganese counts, a decrease in the well failure rate, an increase in production, and an overall cost savings associated with the application of acrolein.   

Picture for Severe microbiologically influenced corrosion (MIC) of pure zinc and galvanized steel in the presence of Desulfovibrio vulgaris
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Severe microbiologically influenced corrosion (MIC) of pure zinc and galvanized steel in the presence of Desulfovibrio vulgaris

Product Number: 51320-14537-SG
Author: Di Wang, Tuba Unsal, Tingyue Gu, Sith Kumseranee, Suchada Punpruk
Publication Date: 2020
$20.00

Zinc and its alloys are used as sacrificial anodes because zinc is an active metal. Carbon steel can be coated with zinc to protect against corrosion. These metals are known as galvanized steel. In this work, microbiologically influenced corrosion (MIC) of pure zinc and galvanized steel caused by a sulfate reducing bacterium was investigated. After 7 days of incubation in 125 mL anaerobic vials with 100 mL culture medium and 1 mL inoculum, the sessile cell count on the galvanized steel was slightly higher than that on pure zinc. The abiotic weight loss for pure zinc was 1.4 ± 0.1 mg/cm2 vs. 4.6 ± 0.1 mg/cm2 for galvanized steel after 7 days of anaerobic incubation at 37oC. The weight losses for galvanized steel and pure zinc were 31.5 ± 2.5 mg/cm2 and 35.4 ± 4.5 mg/cm2, respectively, which were 10X larger than the previously reported carbon steel weight loss in the same SRB broth. Electrochemical corrosion tests confirmed the severe corrosion of these two metals. The corrosion current densities of galvanized and pure zinc were 25.5 µA/cm2 and 100 µA/cm2, respectô€€€vely at the end of the 7-day incubation with SRB, confirming that pure zinc was more prone to SRB MIC than galvanized steel. In both cases, the corrosion product was mainly ZnS. Three MIC mechanisms were possible for the severe corrosion. Extracellular electron transfer MIC is thermodynamically favorable for Zn. Furthermore, the detection of H2 evolution in the vials suggest that proton attack and H2S attack occurred against Zn in the SRB broth with neutral pH after passive film damage by the SRB biofilm.