The separation process is the heart of the offshore production system. Conventional technology requires massive equipment to allow for required separation of oil, gas, water and sand. Most separation equipment is based on gravity separation principles that require larger retention times and low fluid velocities. These separators have over several years been subject to further development by introduction of new separation principles. Advanced separator internals have been an important contributor in this respect. During the last decade, Inline Separation Technology has successfully been introduced to several applications. Inline Separation is separation in pipe segments instead of within large vessels. Especially separation by use of cyclonic forces has been important. Inline technologies for separation of gas and liquid, oil and water as well as sand from liquid and multiphase streams have been developed and are already used extensively in retrofit applications to increase the performance and capacity of existing offshore production systems. As the inline technology matures, total production systems can be developed based on use of inline separation technology. This will allow for substantially more compact and cost efficient field developments. It will also enable new applications, such as heavy oil and deepwater subsea applications, which are not feasible to develop with conventional technology. This paper gives an overview of the inline separation technology and how this technology can be used to make improvements to offshore production system designs.

In an effort to understand separation phenomena, improve separation technologies, and mitigate the uncertainty and risk associated with separator design and operation at elevated pressures, high-pressure separation tests have been conducted at 1,500 psig and 2,600 psig over a wide range of gas flow rates and inlet liquid concentrations. The tests were performed at the Southwest Research Institute® Multiphase Flow Facility using hydrocarbons ? natural gas and a liquid hydrocarbon model fluid (ExxsolTM D110, with components C12-C17). The experimental test section used during this study was equipped with compact, high-capacity separation technologies that accomplish high liquid removal efficiencies while minimizing footprint. The unit consisted of a CDS Separation Systems inline cyclonic separator for bulk liquid-phase removal and a downstream vertical separator equipped with compact internals (i.e., a vane-type inlet device, drainable mesh pad coalescer, and demisting cyclones). The design of the test skid provided significant flexibility to evaluate the performance of the separation devices alone or in combination. In this paper, the high-pressure separation testing approach, performance trends, and impact of the results are presented and discussed. Introduction Efficient gas-liquid separation is essential to the reliability and successful operation of many processes within the oil, gas, and chemicals industries. Poorly designed or inefficient separators can lead to numerous process-related issues. In gas processing, separators are used upstream of rotating equipment (e.g., expanders, compressors, turbines), contactors (e.g., glycol and amine), mol-sieve dehydrators, fuel systems and the like, and are therefore critical to preventing mechanical damage, foaming, fouling, or hydrate formation in downstream equipment. In addition, separators are important to meeting product requirements (e.g., hydrocarbon dew point) or satisfying air emissions and other environmental regulations. The importance of a properly designed separator is quickly realized as costs associated with the repair or replacement of equipment and/or gas treating solvents often far exceed the initial cost of the separator. Gas-liquid separators are designed to handle a mixed-phase inlet stream and use the density difference between the phases to drive phase separation (e.g., remove entrained liquid droplets from a gas-continuous stream). Gravity-based separators often employ more conventional demisting devices (i.e., wire mesh pads or vane packs), and therefore rely on gravity and impingement as the primary separation mechanisms. Unfortunately, conventional gravity separators, and the aforementioned internals employed within, are not always feasible. This is most evident when de-bottlenecking existing facilities (to increase throughput and/or prolong the life of the field) and in the development of resources in challenging environments (e.g., deepwater, arctic regions, or other remote fields) where vessel diameter, wall thickness, weight, or available footprint may be restricted. In such cases, more compact separator internals that use centrifugal forces to drive phase separation can be employed, such as inlet cyclones (bulk phase separation) and demisting cyclones (fine droplet removal). More recently, the demand for compact, efficient gas-liquid separation in such services has launched the development of inline cyclonic devices that employ the same separation mechanism (i.e., centrifugal forces) to achieve bulk phase separation [Fantoft et al., 2010]. Inline cyclonic separators can potentially replace larger, more conventional separators or be paired upstream of a separator to de-bottleneck existing facilities or reduce the footprint in grass-root designs (by reducing the diameter and overall height of the downstream vessel).

Recently the problem of associated petroleum gas utilization in Russian gas and oil production fields has attracted a lot of attention. According to the Russian Government the new strict utilization requirements as well as high flaring penalties will be applied to the oil producing companies starting from 2014. At the same time, increasing water cut during the well production life is another problem facing the oil and gas operation. Thus, optimal multiphase oil/water/gas flow separation will become vital for Russia for successful oil development and exploitation in the near future.Inline separation technology can be the new solution to solve the mentioned challenges. Inline separation is the compact separation in swirl pipe segments. In comparison to the conventional vessel-type separation, the inline technology is simple, low-cost, low-weight, has no moving parts, needs low maintenance, easy to install and operate. These features fit the exigent conditions expected in hostile production environments, and suitable to both new fields and retrofit applications. This paper describes the inline separation technology, including an overview of qualification work and field experiences. The fundamental mechanisms behind these techniques are explained, and recent advances in these methods are emphasized. The paper especially addresses a test program developed for Marlim production site for reservoir support and gives an excellent example how inline technology can be used to make step-change improvements to the gas, oil, and water management. IntroductionToday the global oil industry is increasingly challenged to carry out complex and capital intensive oil and gas developments whilst ensuring that the recovery of the hydrocarbons over the field life is maximized and that safety and environmental demands are met. Oil and gas separation at the oil well is one of the core operations before transport, sale and refinery. Currently, processing becomes increasingly complex while the quality of produced hydrocarbons keeps deteriorating. Changes of water cut and reservoir pressure during field life; switch from primary oil to gas production; developing new fields in extreme environment (arctic, ultra-deep offshore, etc.) and as a result new requirements on equipment -all of that had a great impact on development new methods and approaches in separation technology. Optimal solutions for multiphase oil/water/gas flow separation are vital for further successful oil and gas development and exploitation.Challenging projects often require new technologies to render them profitable. Current separation techniques are usually costly, and because of size and weight requirements, separation equipment greatly affects the space

Compact separation technologies have been gradually introduced into topside facilities during the last decade. Deployments have typically been motivated by a need to debottleneck facilities in mature fields, where a compact unit could be installed into a congested process plant without major reconstruction. While the advantages of compact separation technologies are generally acknowledged, the lack of data regarding performance, flexibility and reliability - as well the absence of process simulation tools - has until now resulted in a limited utilization of compact processing concepts in new field developments. In close collaboration with a major oil operator a program has been established with the aim of developing a Compact Topside Gas/Oil/Water Processing Plant, with high efficiency and reliability, capable of handling the new oil properties and high CO2 content that characterizes the recent Pre-Salt discoveries. Inline ultra-compact separation technologies have been combined with optimized vessel designs to achieve a flexible and reliable processing plant for future FPSO's. During the conceptual design phase extensive process simulations of the complete processing plant have been performed. Dynamic performance modelling has been included into these simulations for each component, allowing detailed predictions of plant performance in the presence of transients. This has been used for design optimisation, evaluating impact of component failure, as well as the development of a control and automation philosophy. Feedback from existing installations has been used to perform a Technology Maturity Assessment of each new technology incorporated in the compact topside facility and to establish a reliability database. For any technology not ranked at the highest Technology Readiness Level the gaps and required qualification activities have been identified. This paper presents the activities executed during the development of a novel topside facility based on compact separation technologies, including Technology Maturity and Reliability Assessment, as well as capabilities of new process simulation tools.

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