Catalin Teodoriu

Application Of Artificial Intelligence Methods In Drilling System Design And Operations: A Review Of The State Of The Art

Abstract Artificial Intelligence (AI) can be defined as the application of science and engineering with the intent of intelligent machine composition. It involves using tool based on intelligent behavior of humans in solving complex issues, designed in a way to make computers execute tasks that were earlier thought of human intelligence involvement. In comparison to other computational automations, AI facilitates and enables time reduction based on personnel needs and most importantly, the operational expenses. Artificial Intelligence (AI) is an area of great interest and significance in petroleum exploration and production. Over the years, it has made an impact in the industry, and the application has continued to grow within the oil and gas industry. The application in E & P industry has more than 16 years of history with first application dated 1989, for well log interpretation; drill bit diagnosis using neural networks and intelligent reservoir simulator interface. It has been propounded in solving many problems in the oil and gas industry which includes, seismic pattern recognition, reservoir characterisation, permeability and porosity prediction, prediction of PVT properties, drill bits diagnosis, estimating pressure drop in pipes and wells, optimization of well production, well performance, portfolio management and general decision making operations and many more. This paper reviews and analyzes the successful application of artificial intelligence techniques as related to one of the major aspects of the oil and gas industry, drilling capturing the level of application and trend in the industry. A summary of various papers and reports associated with artificial intelligence applications and it limitations will be highlighted. This analysis is expected to contribute to further development of this technique and also determine the neglected areas in the field.

A theoretical comparison of cement slurry mixing energy in field and laboratory conditions

The cementing of gas wells, especially those used for underground storage, requires precise understanding of cement properties. CO2 sequestration projects require very-long-term cement integrity, which means that the only way to test the properties of cements used in such applications is in the laboratory. It is common knowledge in the oil and gas industry that the properties of cement slurry obtained from laboratory and field mixing do not correlate very well. This is due to differences in the mixing equipment and procedures followed (API laboratory Waring blender vs. field mixer). The dissimilarity has triggered several research studies that have resulted in the mixing energy concept. This study investigates whether the mixing energy concept can be relied on to reconcile laboratory and field results. Results to date suggest that adequate reconciliation cannot be achieved using calculated mixing energies only, and the authors propose the use of shear rate instead. Additionally, this work evaluates the change in shear rates while pumping slurries through coiled tubing and pipes of different diameters, and the associated possible alteration of cement slurry properties. Two different techniques were simulated in the study, namely the API laboratory method and accepted field mixing, which highlighted the need for a review of laboratory mixing practices towards better prediction of field cement slurry properties.