The automated device adapts an established enzyme assay bacteria bioburden determination manual method to an automated device. Water supplied to the device is collected and filtered to capture planktonic bacteria and particle-associated bacteria (PAB's). The filter is subsequently saturated with a fluorescent-labelled enzyme substrate which reacts with a naturally occurring enzyme activity in living bacteria. A fluorescent compound is released and after extraction, the fluorescence is measured with a fluorometer. The enzyme activity is adjusted for temperature, reaction time and sample volume according to a supplier algorithm and used as a proxy for the bacterial bioburden in a water sample. The device supports remote data collection and remote operation and can process up to twelve samples in 24 hours. The study demonstrates that results from the manual method and automated device are very similar. The study also demonstrated good reproducibility between multiple devices. Installation and long-term operation of the device were also demonstrated on different water types, a with high medium and low biological loads. While more testing and validation are needed, the device proved to be reliable and repeatable for clear seawater and potable water applications producing results as fast as 12 samples in 24 hours while needing regular maintenance to replace analysis chemistry after every 50-analysis run.
Metal corrosion associated with the growth and reproduction of microorganisms is known as microbiologically influenced corrosion (MIC). MIC causes damage to metal surfaces in several water-based industries including drinking water distribution, cooling water equipment, sewage treatment, underground pipes, bilges, piping, and tanks of maritime vessels. MIC is extensively seen in the oil and gas industry. Extensive studies carried out in the United States in 1978 showed that MIC cost to various industries is between $16 and $18 billion.1
Aerobic and anaerobic bacteria are commonly found in oil and gas production and thrive at ocean and petroleum reservoir salinities in the oil and gas industry. The activity of microorganisms is responsible for the corrosion of equipment, plugging of petroleum formation, and souring of the reservoir. The annual cost of all forms of corrosion to the oil and gas industry is estimated at $13.4 billion, of which MIC accounts for about $2 billion.1,2,3,4,5,6
