Thursday 20 January 2022 - 11:09:12 pm

Capital hosts symposium on ''Technique of Using Bacteria for Oil Production"

WAM Abu Dhabi, July 7th, 2008 (WAM) -- The Centre of Information Affairs in Abu Dhabi organized a symposium on "The Technique of Using Bacteria for Oil Production" on Sunday.

The key speakers are Eng. Musallam Al-Mandhari, Head of Process Production Chemistry at Petroleum Development Oman (PDO); and Dr. Saif Nasser Al-Bahry, Assistant Professor of Microbiology at College of Science, Sultan Qaboos University.

Mr. Al-Mandhari presented a paper entitled, "The Use of Microbial Enhanced Oil Recovery (MEOR) Technique in the Oil Industry," in which he first outlined the conventional oil production, which he said, occurs in three stages, primary, secondary and tertiary.

He indicated that in the primary stage, 5-20% of oil will be recovered as a result of the internal reservoir pressure, while in the secondary stage, reservoir pressure is maintained artificially by injection of water (Water Flooding) or/and injection of immiscible gas, where 30-40% of oil can be recovered, he pointed out.

But, he explained, where the methods used in primary and secondary stages can no longer increase the recovery factor or cannot be applied, tertiary recovery methods can be utilized, that is, the Enhanced Oil Recovery (EOR), explained the Senior Production Engineer at PDO Oman.

He pointed out that the EOR technique can be classified as thermal, chemical (acids, synthetic surfactants and polymers) and miscible gas displacement. But all of these methods are expensive and are detrimental to the environment and in some cases, such as CO2 injection; there is no sufficient source of gas, he noted.

He added that the efforts to come up with an alternative cost efficient EOR technology, because of the above difficulties, has always been a challenge among the petroleum companies, including the Petroleum Development of Oman (PDO).

Therefore, he said, several methods of EOR technologies have been developed and tested globally including techniques in biotechnology by using exogenous or indigenous microbes, mentioning that this process is known as �Microbial Enhanced Oil Recovery (MEOR)'. This method was first introduced in 1926, and since then, the MEOR technologies have been modified and applied in oil industries, he pointed out.

He mentioned that field applications of MEOR have been conducted in the United States, Australia, China, Romania, Russia and India, but with different results. He indicated that while some oil producers, using MEOR technology, reported a substantial increase in oil recovery ranged between13% to 204%, other companies reported no gain.

For these reason, he explained, Petroleum Development Oman (PDO) has made a joint venture with researchers from the Department of Biology, College of Science and the Department of Petroleum and Chemical Engineering, College of Engineering in the Sultan Qaboos University to conduct research and to come up with successful applications of the MEOR biotechnology in order to increase productivity of oil wells in the Sultanate and to avoid any negative impact on the production of oil.

On his part, Dr. Saif Al Bahry explained the Microbial Enhanced Oil Recovery (MEOR) technique in Oman, using slides. He displayed the advantages and disadvantages of this technology compared to other Enhanced Oil Recovery (EOR) methods. He stated that MEOR is cheaper and suits a larger group of reservoirs, but its impacts are unexpected. It is also environmentally friendly, he said, giving other examples of its advantages and disadvantages.

He pointed out that field applications of MEOR have been conducted in the United States, Australia, China, Romania, Russia, and India, with the enhanced oil production results varying from no impact to 13%, 19%, 36%, 50-56% and 204%.

He also tackled the various factors affecting microbial growth in oil field, using curves and other illustrative means. For instance, he used curves to explain the growth rate versus temperature for five environmental classes of Procaryotes, showing that most Procaryotes will grow over a temperature range of about 30 degrees, referring to three cardinal points: Minimum, optimum, and maximum.

Talking in detail about the factors effecting microbial growth in oil field, in particular, he indicted that when bacteria are grown in a closed system (also called batch culture), like the test tube, the population cells almost always exhibit these growth dynamics: cells initially adjust to the new medium (large phase) until they can start dividing regularly by the process of binary fission (exponential phase). He pointed out that, when their growth becomes limited, the cells stop dividing (stationary phase), until eventually they show loss of viability (death phase). And he went on describing these factors.

He also explained in detail the mechanisms of the MEOR technology, using curves and other illustrative means.

Dr. Saif Al Bahry said that there are many challenges facing this research project, conducted by Petroleum Development Oman (PDO) and Sultan Qaboos University. Among these challenges are to know the right kind of bacteria to be used in the right place within the right environmental and nutritional conditions, etc., he indicated, stating that knowing this will effectively enhance the application of this technique in the future.

He also tackled various applications of the MEOR technique, such as single well stimulation, MEOR water flooding, Water division, Paraffin removal, viscosity modification, heavy oil modification, and activation of formation in microorganism.