In the last few years, large efforts have been made to develop advanced and smart technologies that can predict and prevent asphaltene precipitation. In the history of asphaltene deposition science, two schools of thought have emerged to predict the phase behavior of asphaltene. One school uses colloidal science techniques, believing that asphaltene exists in oil at a colloidal state. The other school adopts thermodynamic methods, believing that the asphaltene occurs in oil in a true liquid state. The main drawdowns of asphaltene deposition in some reservoirs that are prone to asphaltene precipitation are the alteration of reservoir rock's wettability, and the plugging of the formation, flowlines and separation facilities. Different production strategies have been developed to eliminate or reduce the asphaltene precipitation. As asphaltene properties are dependent on its composition, as well as the reservoir temperature and pressure, thermodynamic and kinetic control strategies are utilized to control the pressure and temperature of the system or the conditions of solid formation. Common intervention techniques include stimulating the well periodically using a mixture of acid, xylene, and mutual solvent. Advancement in the asphaltene flocculation-inhibitor treatments allows it to be used in treating the asphaltene in the reservoir without damaging the formation. There are some limitations and environmental restrictions on the current conventional intervention techniques associated with using low flash-point chemicals. These limitations can be resolved by using environmentally friendly techniques, such as laser energy to disturb asphaltene particles. This paper will discuss the asphaltene precipitation and deposition phenomena, preventive and detection techniques, and intervention methods and their limitations, providing a comprehensive overview on the current practice in asphaltene remediation and prevention.

Drilling in a mature Saudi Arabian oilfield proved to be a steep but successful learning curve for a Saudi Aramco Engineering team. Over the years, the encountered challenges were handled by applying tested methods implemented in the area, which failed to turn around the desired results in this field. It became clear that field specific practices and procedures were necessary and, as a consequence, old paradigms were challenged to improve the performance while mitigating downhole challenges and eliminating excessive non-productive time (NPT). Problems typically confronted in the area were pinpointed using historical data revision, and analyzing of previous field experience regarding common drilling practices. Focus was placed upon troubles impacting the two intermediate hole sections in which a number of problems arose including time-dependent unstable shales and interbedded permeable layers with different pressure regimes. Improvement of drilling the sections of concern necessitated a drastic and systematic revision of many aspects such as drilling fluids, BHA design, and drilling drive. In addition, long lasting field specific drilling practices such as connection practices and wiper trips were challenged through technical analysis, aiming to boost operational efficiency. The recommendations were implemented in stages enabling evaluation of results, and ensuring a smooth transition from erstwhile practices. The new approach successfully assisted in overcoming drilling troubles, resulting in outstanding operational excellence levels. Wells were drilled faster and non-productive time (NPT) was significantly reduced. The results are benchmarked against wells delivered over a period of 4 years. As of today, the wells drilled and completed exhibited an outstanding improvement, increasing drilling rate of penetration and dropping NPT by 71%. Furthermore, the main key performance indicator (KPI), footage per day, has significantly increased by 44%. The paper presents the development of set of optimized practices and procedures that collectively replaced deep-rooted field practices that are not suitable for the modern-age ERD wells. It walks through the challenges, the thinking process, the technical evaluation, and field implementations. This optimization has resulted in a stellar increase in drilling performance while cutting back on non-productive time.

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Horizontal, heterogeneous reservoirs of low permeability present various challenges and drilling risks. The likelihood of encountering potential problems can be greatly increased when there is a minimal understanding of geology and pressure regime in the area of interest. A similar case was tackled while drilling an observation well. The drilling challenges were carefully recognized and highlighted to be properly addressed. Planning and risk mitigation measures included the introduction of a set of drilling and tripping practices to minimize potential risks while drilling the well. Details of the comprehensive evaluation program and logging tools were discussed along with drilling fluid design. In addition, rigorous efforts were exerted on BHA design, drilling dynamic modeling, torque-and-drag simulation, and hydraulic management. The integrated planning and drilling approach implemented in the subject well has ensured the safety of drilling operations through real-time formation pressure evaluation, which has allowed for quick mud weight control while drilling. In addition, the drilling fluid was pre-treated with sized bridging materials to build an impermeable filter across the anticipated streaks of permeable intervals. Improved drilling and tripping practices have helped in drilling a trouble-free well, where the risk of differential sticking was minimized. An advanced well-engineering software was used to design the rotary steerable system (RSS) and the logging-while-drilling bottomhole assembly to reduce the severity of stick/slip vibration and minimize wellbore contact across the lengthy BHA. This has led to an enhanced and optimized drilling performance, which was complemented by real-time monitoring to allow for on-the-spot decision making. The collected data in the well will help in identifying and modeling reservoir characteristics in terms of porosity, permeability, formation pressure, and fracture identification. The employed integrated planning and drilling approach has successfully enabled meeting the objective of a challenging well in which a high level of uncertainty was present. The delivery of the well will help in making better reservoir management decisions and increasing the confidence in geological and petrophysical models.