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During the last years, a lot of work have been done focusing on development of low shear valves solutions to be applied on petroleum primary process plants. The main goal of the low shear valve is to generate water-in-oil (WiO) and oil-in-water (OiW) emulsions that can be easier treated by the separation process, when compared with emulsion generated by conventional valves. This paper presents experimental results of a comparison between a commercial low shear valve and a conventional valve. Both valves were installedin parallel on a test loop and the fluids used for all test matrix points were potable water mixed with Petrobras Marlim Crude Oil. The test matrix includes variation of differential pressure on valves, flowrates and concentration of water/oil. Samples were collected downstream of both valves and led to settle into several residence times. The degree of contamination of both phases were analyzed for all residence times. The benefit of the application of low shear valve was quantified for all test conditions and the results were very promissory. The pressure drops across valves were selected considering typical values observed at Petrobras choke valves and control level valves. For almost all test matrix's points the emulsion generated by the low shear valve showed at least a slight benefit, allowing have better water quality after settling. The low shear valve solution showed to be a promissory technology but the magnitude of the benefit is very influenced by valve process operation conditions.

Particle tracking velocimetry (PTV) measurements have provided inner flow features within plate and shell heat exchangers (PSHE). Measurements have been performed at Reynolds number 3450, based on the bulk velocity and the PSHE geometry at the channel mid-section. Particle trajectories have been measured. Organized flow features prevail in the channel inlet, whereas a highly turbulent flow field occurs at the channel outlet. A recirculation zone characterizes the turbulent flow field at the outlet. Gravity has been shown not to affect flow and heat transfer at this Reynolds number. The mean velocity profile is non-uniform at a given channel cross section. Friction factors developed for Plate Heat Exchanger (PHE) applied to the PSHE geometry with the bulk velocity at the channel mid-plane were found appropriate for design purposes. Furthermore, friction factor, Nusselt number and forces due to shear stresses were locally estimated for the whole channel area. Potential break-down locations have been identified.

The demand for higher heat transfer effectiveness has stimulated the combination of compact heat exchangers and additive manufacturing. The potential to fabricate complex geometries with different materials can optimize the trade-off between heat transfer and pressure drop. In this work, theoretical models for thermal and hydrodynamic performance were developed for a cross-flow compact heat exchanger manufactured with the SLM process, an alternative to Printed Circuits Heat Exchangers. The heat exchanger core has a cubic format with 100 mm edge and 2 mm channel diameter. The raw material used is AISI 316L stainless steel. Furthermore, the relative density of the prototype is 99.8% and the surface roughness measured was 12.21 µm. The one-dimensional steady-state with circular mini channels models are validated with experimental data. The experiments were evaluated in laminar, transition, and turbulent regimes, with different temperatures. The theoretical models have a good agreement, with 3.3% and 15.3% average errors for the thermal and hydrodynamic models. Besides, the impact of surface roughness in the pressure drop was negligible. The influence of replacing the core material in the thermal performance is significant in the turbulent regime.

Fatigue life of plate and shell heat exchangers has been determined by experiments. Tests occurred with the aid of a pneumatic-hydraulic setup in which plate pack samples were internally pressurized by water. The samples were exposed to cyclic pressure loads varying from ambient to service pressure in the range 1.0–1.4 MPa, typical operating pressure range of crude oil production sites. Stress determination was possible due to strain gauge measurements. A heterogeneous stress field occurs along the corrugated plate due to its complex geometry. The external welded region is the preferential failure location. An average stress-life curve has been provided with 50% failure probability in accordance to ISO-12107. Fatigue strength reduction factors at the critical welded locations were determined via elastic stress analysis as proposed by ASME procedure. PSHE useful life increases with decreasing spacing between plates.

Abstract The objective of this paper is to describe the adopted procedures and operations that were used to process commissioning and start-up the Marlim Subsea Oil and Water Separation and Water Re-injection System. This system is much more complex than the conventional subsea manifolds and, similarly to the previous phases of this project, the commissioning and start-up phases also faced many challenges that had to be overcome. Several subsea equipment are part of the system; among them we should mention an unconventional "harp" gas-liquid separator, an oil-water "pipeseparator", cyclonic desanders (both for multiphase inlet stream and for produced water stream), two stages of hydrocyclones to remove oil from produced water and a water injection pump. Besides these equipments, instruments and multi-functional control modules are also part of the system. The problems faced during commissioning and start-up activities and the adopted solutions to solve them are also discussed. This paper will cover the start-up activities describing the following sequence:re-start-up of the production well through the subsea system by-pass line to topside,alignment of well multiphase production stream through the subsea separation system to check separation performance and suitability of produced water quality for re-injection andfinally start up of re-injection of produced water into the injection well. The requirements for logistic support that are very much different from the ones required for topside installations are also discussed. New " paradigms" of operating facilities imposed by subsea environment constraints, are also suggested and discussed. Introduction The Marlim Subsea Oil and Water Separation and Water Re-injection System (SSAO) is an innovative pilot project installed as a Pilot System for the well MRL-141, connected to the host production unit (FPSO), P-37, in Marlim Field, Campos Basin. The objectives of the project are: platform debottlenecking of the water treating facilities; increasing production by reduction of back pressure on the wellhead. Besides these objectives, another important aim of the project is to prove the concept and qualify the adopted technologies for future other applications. As a pilot project, the SSAO was designed to work for a minimum of 5 years, without retrieving of any components, removing, treating and re-injecting free water from the production of MRL-141, as shown in Table 1.

Abstract This paper initially discusses the tendency to wider the conceptual envelop of subsea systems in oil production installations. From the conventional boosting systems to more complex gas/oil/water separation equipment and even polishing devices for coarsely separated fluid stream, there is nowadays a tendency to increase the complexity of subsea production systems far beyond manifolds and other maneuver stations. In sequence the pros and cons of subsea processing as an alternative to conventional topside primary processing are also discussed. Restrictions of the subsea environment and the consequent requirement for unconventional solutions and equipments comparing to topside traditional separation equipment are also mentioned. The limitations of the expression " subsea processing" are emphasized and both advantages and technological gaps of new " building blocks" for processing plant for topside and subsea application are discussed. Besides, operational aspects are also addressed so as to emphasize the new challenges subsea systems pose to operation crew: some important paradigm changes should be captured by operators when changing from a topside plant to a subsea system. The problems arising from having a new subsea system connected to an old production unit in a brown field are also discussed. The drive for the qualification of new conceptions and new equipment is approached not only for subsea use but also for the new generation of topside production facilities. The paper tries to bring some conclusions on the means to allow further development - filling up the gaps - and qualification of the new " compact" or " in-line" building blocks for subsea processing plants. However, it must be emphasized that the focus of this work is on processing technology not on equipment or marinization technologies. Thus, subsea engineering (hardware) qualification is beyond the scope of this work. 1. Introduction In offshore oil and gas production systems, subsea equipment started with wellhead components and flow distribution manifolds three or four decades ago. Some time later, boosting systems (including dynamic equipment - pumps either monophase or multiphase, and, eventually compressors) were conceived as means of turning feasible production of remote marginal fields with long tie backs to production platforms. But even these initiatives were initially assumed as part of the strategy of flow assurance in the offshore production fields. The concept of primary processing of produced fluids was kept in accordance with the usual expression " surface oilfield operations" and that " surface", in the offshore case, was considered as being provided by the deck on the offshore production unit. Seabed was not regarded as supporting site for primary processing facilities. The idea of having at least part of the primary processing (mainly phase separation) at the subsea environment was driven by the necessity of boosting liquid and gas streams to flow to a greater distance - again flow assurance demand. Subsea separation was initially regarded as potentially complicated from the operational point of view, and as a consequence, in parallel to the new conceptions of subsea gas-liquid separation, an impulse on the development of multiphase pumping system was also boosted.

Abstract This paper presents the selected concept, the main challenges of the adoptedscenario and in consequence the requirements for a development of an extensiveTechnological Qualification Program performed on the components and on thewhole sub-sea water separation and re-injection pilot system for Marlim field -known as SSAO Marlim Project. Due to being a pioneer project, even consideringthe previous Troll and Tordis sub-sea separation and re-injection systems, itwas necessary to perform a very extensive and broad Technological QualificationProgram (TQP). Two main characteristics of the SSAO project are responsible forthe mentioned pioneer character of the project. Initially, in opposition to thementioned existing systems, separated water has to be re-injected in theproduction reservoir formation, due to non available disposal reservoir inproduction field area. Thus, required water quality, relating to oil andsediment content after separation, was very strict in order to avoid loss ofinjectivity. Furthermore, due to the deep water depth of the installation site(870 m) and due to the fact that the SSAO is a pilot for future deep waterinstallations, conventional gravity separators - as used in the mentionedprojects - would not be feasible and new technologies, not yet used elsewhere, have to be adopted.