The nature of operations in the petroleum industry involves a significant amount of process and personal safety risks. Industry operators and service providers desire to achieve the safety goal of no fatalities or harm to personnel, and no damage to assets and environment. Most operating companies and service providers have over time developed well-structured frameworks for Process Safety Risk Management. Aspects of personal safety especially operations-related are also well managed. A significant number of incidents have resulted from human factors related to stress and fatigue. Fatigue is a state of sleepiness with the associated lack of mental alertness caused by sleep deprivation. It is imperative that the industry recognizes the threat posed by fatigue and put the right measures in place to minimize the associated risks. This paper intends to raise awareness on the impact of fatigue in the petroleum industry and recommend a framework for Fatigue Risk Management (FRM). A structured framework entails embedding of FRM Systems, which include studies, gap analysis, closure plans, and development of FRM plans, implementation, audits, and reviews. The FRM system will ensure a safe working environment using a risk model to review outcomes and recommend actions. The embedment of this system which is based on Safety Management System (SMS) in the workplace ensures appropriate mitigations, effective controls, timely implementation, periodic audits and reviews. This system may be deployed in all areas of petroleum industry operations spanning Exploration and Production to the downstream sector. Similar models have been deployed in other industries with success.

Pressure-Volume-Temperature (PVT) relationships have long been studied as a basis of understanding the phase behavior of fluid systems. In order to understand the behavior of these fluid systems, smaller quantities usually referred to as samples are obtained and studied under varying PVT conditions in order to define the character of the fluids. PVT experimental measurements provide key data for reservoir engineering and production applications; however the importance of having valid samples may be overlooked during preparation of the laboratory study and interpretation of the results.

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Many optimization problems related to integrated oil and gas production systems are nonconvex and multimodal. Additionally, apart from the innate nonsmoothness of many optimization problems, nonsmooth functions such as minimum and maximum functions may be used to model flow/pressure controllers and cascade mass in the gas gathering and blending networks. In this paper we study the application of different versions of the derivative free Discrete Gradient Method (DGM) as well as the Lipschitz Global Optimizer (LGO) suite to production optimization in integrated oil and gas production systems and their comparison with various local and global solvers used with the General Algebraic Modeling System (GAMS). Four nonconvex and nonsmooth test cases were constructed from a small but realistic integrated gas production system optimization problem. The derivation of the system of equations for the various test cases is also presented. Results demonstrate that DGM is especially effective for solving nonsmooth optimization problems and its two versions are capable global optimization algorithms. We also demonstrate that LGO solves successfully the presented test (as well as other related real-world) problems.

The evaluation of the recoverable hydrocarbon volume and further development opportunities in complex reservoirs (where two or more reservoirs are hydraulically connected) primary challenges the engineer faces in managing such reservoirs. In this study, multi-tank material balance models have been built to solve these problems. The key criteria for a robust material balance modelling of hydraulically connected reservoirs in a single system are: (i) transmissibility across the reservoirs should be properly defined. Transmissibility is a major modelling component in achieving sound multi-tank MBAL models. It is useful to the estimation of the rate of aquifer movement across the reservoirs. (ii) Good understanding of the geology and production data of the reservoirs is helpful in estimating the appropriate transmissibility. (iii) Sufficient and quality Carbon-Oxygen logs, BHP and production data. CO logs are very important for proper calibration of hydrocarbon contact. Accurate BHP data is critical in the establishment of dynamic communication and matching of simulated versus measured reservoir pressure. In this paper two cases with over 30 years of production history are discussed in detail including the full methodology and the associated results. The results from these studies show good and reliable outcome which has provided the basis for the reported hydrocarbon resource volumes of the reservoirs (B1.0X, B1.0N, C1.0X, E9.0X, E10.0X, E11.0X, G1.0X, H1.0X) Results were compared with other methodologies (existing simulation models and DCA of NFA wells) and indicate good comparisons. The number of development opportunities in the 8 reservoirs were optimised from 22 to 20 wells using the multi-tank material balance model. Despite some known limitations of material balance generally, multi tank material balance model has proven to be a simple and reliable methodology in evaluating complex reservoir system with hydraulic communication. Especially, in situations where time and budget constraints will not support full field reservoir simulation modelling.