In a conventional separator, with the exception of mist elimination, separation is usually achieved by allowing the fluids to have a few minutes retention time under the influence of gravity. Separation equipment can be reduced in size bythe application of a centrifugal force, which is many times gravity. The result of this is that centrifugal separators can be manufactured as a very compact unit. One step further is to fabricate the equipment according to pipeline design codes so as to avoid the complexities associated with the use of pressure vessels. Inline separators are based on cyclonic technology and can be regarded as mono-cyclones. At the moment two types of separators are available and qualified for the market. The first one is a Degasser where the aim is to separate gas from a liquid continuous flow. The second type is a Deliquidiser acting in the opposite way namely separating liquid from a continuous gas stream. Besides this, liquid/liquid inline separators are in development at the moment. Besides the compactness of these inline separators, the flexibility in terms of turndown, pressure drop and efficiency is a significant benefit compared to conventional separation equipment. The paper describes several types of newly developed inline separators and inline separator-systems. In addition current installations, namely those on Statoil Statfjord B and Sleipner T platform and on the BP ETAP platform, along with their specific benefits and cost savings are discussed. It will be shown that inline technology can and has played a major role in the de-bottlenecking and upgrading of existing top-side facilities. Besides this several sub-sea applications on new and existing oil and gas fields are currently being assessed for the application of this inline technology. Introduction The inline technology described in this paper is a result of a joint development program between CDS and Statoil. Recently, inline technology has received a lot of attention due to the considerable weight and space savings that can be achieved. In addition to new build topside and sub-sea applications, inline technology can and has played a major role in the de-bottlenecking and upgrading of existing production facilities.In a conventional separator, with the exception of mist elimination, separation is usually achieved by allowing the fluids to have a few minutes retention time under the influence of gravity alone. Therefore a way in which the size of this equipment can be reduced is by the application of a centrifugal force with a magnitude that is many times gravity. The result of this is that the system can be manufactured as a very compact unit. One further step is to manufacture the equipment in accordance with pipeline design codes so as to avoid the complexities associated with the use of pressure vessels. This paper describes several types of newly developed inline separators and inline separator- systems. In addition current installations, namely those on Statfjord B, Sleipner T and ETAP, along with their specific benefits and cost savings are discussed. Inline Technology Inline separators are based on cyclonic technology and can be regarded as mono-cyclones. At the moment two types of separators are available and qualified for the market. The first one is a Degasser where the aim is to separate gas from a liquid continuous flow. Whereas the second type is a Deliquidiser acting in the opposite way, separating liquid from the gas continuous stream.

The influences of compressibility and turbulence level on boundary layer transition are studied using a Ludwieg tube set-up. Heat transfer measurements are performed on the flow over a flat plate. The Mach number is varied between 0.16 and 0.56 while the unit-Reynolds number is kept constant. Several turbulence generating grids are used giving turbulence levels between 1.2% and 4.4%. Increasing the Mach number results in a decreasing turbulence level. Besides, the transition start Reynolds number increases. The results indicate that besides the turbulence level another parameter is desired for the existing transition models. The dimensionless spot parameter is influenced by both the turbulence level and the Mach number. A tentative conclusion is that the start of transition depends on the inertial range minimum frequency in the energy spectrum while the shape of the transition curve, i.e. the intermittency, depends on the corresponding length scale.

In the past decade the use of very compact processing equipment, sometimes referred to as 'Inline separation equipment' has become more and more popular. In a number of cases, it has been possible to successfully debottleneck severely restricted process systems through the use of inline equipment. Successful examples on for instance Statoil platforms like those of Statfjord have been well documented. However, compact separation technologies have not yet been able to gain general acceptance as standard building blocks for new process systems, or to take it one step further, have not yet been able make classical separation technologies obsolete. The perceived operational disadvantages of inline equipment consist of it 1) being relative intolerant to variations in operating conditions (restricted turndown range) and 2) being complex equipment to design as no accurate, generic design rules exist. Moreover, most inline equipment is customized for a specific application. This paper will highlight the development of a new generation of inline separation equipment. The new equipment is characterized by a much more efficient swirl generation. The principle of operation of most compact separation equipment is based on creating strong centrifugal forces that drive the separation of the well fluids. It is shown that the more efficient generation of this driving force creates much wider turn down ranges of critical operating conditions. It is described how rigorous performance mapping has taken and still takes place under realistic operating conditions (both regarding scale and physical characteristics of test fluids) to prevent the design uncertainties that have sometimes hindered the correct application of these technologies today.An example will be presented how these new inline components of which the performance characteristics are now well known can form an extremely compact process system with a pronounced tolerance against transient operating conditions (like slugging).

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractCompact separation has been a "buzz" word in design of new facilities for many years now as more reserves are being located in deeper waters. However, upgrading existing facilities to handle more production is also important. Third party processing, under-estimated reserves, or recently located nearby reserves result in higher rates. Space then becomes a premium especially in the deep water facilities where extra space may have been minimal in the design. This paper will discuss some new and proven technology not only for compact separation, but also for increasing gas/liquid separation capacities of existing vessels.Applications of the technologies will also be presented.

No abstract