Laboratory Experiment, Production Performance Prediction Model, and Field Application of Multi-slug Microbial Enhanced Oil Recovery

Abstract

Because of heterogeneous formations and multi-scale fractures, the accurate evaluation of microbial enhanced oil recovery is faced with numerous difficulties. For the purpose of evaluating the production performance of multi-slug microbial enhanced oil recovery, this work studied the influence of microbial activity on the properties of oil and porous rock and the effect of microbial slug compositions on oil recovery. A mathematical model was built on the basis of the experiment, using the Buckley–Leverett theory and production decline laws. The model is a combination of the characteristic curve of the water cut change and the exponential decline law of oil production, which could predict oilfield production performance, including water breakthrough time, cumulative oil production, and relationship between the water cut and water saturation of the flood front. In comparison to the numerical simulation method, this approach has no additional restrictions because of grid orientation effects, which were found to be suitable for predicting production performance of either large-scale or whole block. The predicted values of the model were compared to the measured values of a field test, indicating that the model predicted the performance of microbial enhanced oil recovery precisely. More specifically, the maximum prediction error of a single well was less than 10%, and the prediction error of the whole block was less than 3%, suggesting the suitability of the model in predicting production performance. In conclusion, it is believed that the multi-slug seems to be a better approach for enhanced oil recovery and that the mathematical model would accurately predict the production performance of microbial enhanced oil recovery.

Application of Guar Gum Degrading Bacteria in Microbial Remediation of Guar-Based Fracturing Fluid Damage

“…The formation water sample collected from an oil well in Gudong reservoir of Shengli Oilfield in Eastern China was used as inoculum for the enrichment of guar gum degrading bacteria. The temperature of the oil reservoir is approximately 53 °C and formation depth reaches 1000–1100 m. The artificial brine water (shown in Table ) with the total salinity being 91173 mg·L –1 used in the experiment was prepared according to the salinity of the brine in the Ansai Oilfield, where one of the important ultra-low-permeability reservoirs in China exists …”

Isolating, identifying and evaluating of oil degradation strains for the air-assisted microbial enhanced oil recovery process

“…And as such, the high reservoir pressure would impel the injected air to disperse even better in the bacteria solution. Concrete method for oxygen-consumption model was shown in Fig 5 [1,10].…”

“…The current rapid pace of economic and social development worldwide necessitates the use of ever-increasing amounts of resources [ 1 ]. At the same time.…”

Microbial enhanced oil recovery: interfacial tension and biosurfactant-bacteria growth

“…MEOR mechanism adapts the chemical-based EOR (Hartono et al 2017), however, it corresponds to a combined distinct-EOR because microbes could produce biosurfactant, biopolymer, and gas simultaneously. There are other mechanisms such as the consumption of hydrocarbon and degradation of heavy long-carbon-chains into light and short (Sen 2008;Gudina et al 2012;Cheng et al 2014;Patel et al 2015;Cai et al 2015;Varjani and Upasani 2016;Zhao et al 2018;Iraji and Ayatollahi 2018).…”