Bacteria
Timely monitoring of bacteria in the oilfield is critical to producers, as “problems” quickly lead to system wide failures. J&L Laboratories is here to provide you with monitoring services from our state of the art lab, providing you with protection against the threat to your oil and gas producing systems.
Serial Dilution Bottles (“bug bottles”)
J&L Laboratories recommends following the methodologies prescribed in NACE TM0194-94, item No. 21224, as other methodologies such as API RP 38 have been withdrawn. Sulfate reducing bacteria (SRB) are of primary concern, as they can proliferate and cause severe under-deposit corrosion. If SRB are not controlled during the drilling/stimulation process, the entire field may become “sour” due to the H2S produced by SRB. Acid producing bacteria (APB) are also of concern, as they will cause corrosion due to acetic acid production, which drops the pH, often leading to corrosion. Bug bottles come in a wide range of broth TDS concentrations. The selection depends on the TDS of the brine water. A simple hydrometer test or chloride titration can assist in selecting the appropriate broth TDS concentration.
Customer notes:
It is recommended that serial dilution bottles be inoculated in the field. Upon removal from the system, the water sample’s chemistry begins to immediately change. If the serial dilution bottles are not shot close to the time of sampling, the final bacteria counts will most likely be skewed due to the change in viability. APB and SRB bottles can be provided and returned to J&L Laboratories for incubation. At J&L Laboratories, we can train our customers on how to properly perform the inoculations on the serial dilution bottles. If requested, J&L will perform the serial dilutions in lab upon receipt.
The number of bottle turns will be reported up to 4 bottles, please see chart below (source NACE TM0194-94). 0-1 turns are generally considered to be insignificant. 2 bottle turns are marginal. 3-4 bottle turns typically necessitate remedial measures.
Bottle No. Dilution Factor Number of bacteria in original 1mL water sample
1 “1:10” “1-10”
2 “1:100 “10-100”
3 “1:1000” “100-1000”
4 “1:10000” “1000-10000”
ATP
J&L Laboratories utilizes the industry leading OSP Lifecheck Luminometer to detect ATP from planktonic (free floating) bacteria. Adenosine triphosphate (ATP) is the chemical signature of life, present in all living cells. Once a living cell dies, the ATP is destroyed within seconds by an enzyme. The ATP test is useful in showing the total bacteria load and does not require a 28-day incubation as with serial dilution bottles. However, it does not distinguish between bacteria types.
Customer notes:
Sampling for ATP analysis is the most crucial aspect of the test. Improper sampling or waiting to turn the water sample in until the following day will invalidate the ATP test. Samples should be turned in the same day before the lab closes. Results are reported in pg/mL and microbial equivalents per milliliter (ME/mL).
See table and explanation below for interpretation (source: OSP).
Microbiologically influenced corrosion (MIC) is a potentially catastrophic result of unchecked bacterial activity and can seriously compromise the integrity of materials and important infrastructure. Reservoir souring also has the potential to jeopardize oil and gas projects and understanding its mechanics is key to mitigating its risks, such as diminished oil quality and the toxic effects of hydrogen sulfide.
To investigate, discuss and address your oilfield microbiology needs, you need an experienced, reliable partner to offer world-class knowledge and support in both onshore and offshore environments.
Informed by decades of experience and independent research and development, we provide a complete range of oilfield microbiology Total Quality Assurance solutions designed to comply with legislation and best practice.