Knowledge

Keyword: environmental impact

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Cost-Effective ERT Technique for Oil-in-Water Measurement for Offshore Hydrocyclone Installations

Petar Durdevic, Leif Hansen, Christian Mai, Simon Pedersen & Zhenyu Yang

The goal of this paper is to introduce and design a cost-effective Oil-in-Water (OiW) measuring instrument, which will be investigated for its value in increasing the efficiency of a deoiling hydrocyclone. The technique investigated is based on Electrical Resistivity Tomography (ERT), whose basic principle is to measure the resistivity of substances from multiple electrodes and from these measurements create a 2-D image of the oil and gas component in the water. This technique requires the measured components to have different electrical resistances, such as seawater which has a lower electrical resistance than hydrocarbon oil and gas. This work involves construction of a pilot plant, for testing the feasibility of ERT for OiW measurements, and further exploring if this measured signal can be applied as a reliable feedback signal in optimization of the hydrocyclone's efficiency. Different algorithms for creating 2-D images and the feasibility of estimating OiW concentrations are studied and evaluated. From both steady state and continuous laminate flow perspectives, with respect to the objective which is to use this measurement for feedback control purposes.

IFAC-PapersOnLine / 2015
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Extraterritoriality from the Port: EU’s approach to jurisdiction over ship-source pollution

Nelson F. Coelho

Ship-source pollution represents a threat to the environment, regardless of where it occurs. The European Union has been developing standards that aim to counter accidental, operational and intentional pollution in the waters under its member-state's jurisdiction. However, and precisely because marine pollution knows no boundaries, the EU is not coy in contemplating what ships do beyond waters under the sovereignty of its member states. This article analyzes the international legality of EU claims to port state jurisdiction over ship-source pollution. It demonstrates that port state jurisdiction is today not only a means to ensure compliance with international standards but also a means to unilaterally enforce more stringent environmental standards.

Spanish Yearbook of International Law / 2015
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Cleaning the Produced Water in Offshore Oil Production by Using Plant-wide Optimal Control Strategy

Zhenyu Yang, Simon Pedersen & Petar Durdevic

To clean the produced water is always a challenging critical issue in the offshore oil & gas industry. By employing the plant-wide control technology, this paper discussed the opportunity to optimize the most popular hydrocyclone-based Produced Water Treatment (PWT) system. The optimizations of the efficiency control of the de-oiling hydrocyclone and the water level control of the upstream separator are discussed and formulated. Some of our latest research results on the analysis and control of slugging flows in production well-pipeline-riser systems are also presented. The ultimate objective of this research is to promote a technical breakthrough in the PWT control design, which can lead to the best environmental protection in the oil & gas production, without sacrificing the production capability and production costs.

IEEE Press / 2014
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The Authority of Humanity: An analysis of the institutional protection of the geographical redoubt of the common heritage of humanity in the legal-political context of the phenomenon of the expansion of continental platforms beyond 200 miles of sea

Nelson F. Coelho

The legal limbo that defines the maritime space over which the process of delimitation of the outer continental shelf is applied appears today as an eminently practical question that needs to be addressed. The institutional framework provided by UNCLOS, which establishes the existence of an internationalized space on the seabed - the area - seems limited to respond to a debate that confuses Geology with Law. This article focuses on the powers of the International Seabed Authority as an agency authorized to act on behalf of Mankind by exploring its weaknesses in its exercise of this mandate in the context of that process. By analyzing the conflict between the expansionist goals of States and the embodied principle that gives the Authority the assignment to act on behalf of Mankind in securing a space that, according to the text of the Convention, belongs to it, we conclude that there are apparent inconsistencies in the institutional framework created the Montego Bay Convention. In our exegesis of Part XI of the Convention, we work on the cogent force of that principle and raise questions about the legal legitimacy of the entire process, ie in the absence of a clear statement by the above-mentioned Authority. We conclude that the text of the Convention provides the possibility of a direct intervention by the Authority but that there are still no political conditions for such a possibility to be realised.

Instituto Jurídico da Faculdade de Direito da Universidade de Coimbra: Estudos de Doctoramento & Mestrado / 2014
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Control of Variable-Speed ​​Pressurization Fan for an Offshore HVAC System

Zhenyu Yang, Simon Pedersen & Petar Durdevic

Due to the harsh weather conditions, severe spatial limitations and extremely high safety requirements, the indoor climate control for offshore oil & gas production platforms is much more challenging than any on-shore situations. For instance, the indoor pressure of man-board quarters should be kept all the way above the ambient pressure according to safety regulations. Meanwhile, the indoor air needs to be regularly changed in order to guarantee the indoor air quality. Both requirements could be possibly achieved by automatically manipulating either the throttle valve located at the terminal of the inlet channel in the considered Heating Ventilation and Air-Condition (HVAC) system, or the pressurization system located inside the inlet channel, or both of them in a coordinated way. A Model-Predictive Control (MPC) solution to control the inlet throttle has been proposed in our previous work. This paper proposes a set of control solutions to regulate the variable speed pressurization fan system such that the energy efficiency of the considered HVAC system can be explicitly considered. A combined feed-forward with a PI-based feedback control solution, and an MPC solution are proposed based on derived simple system models. Some preliminary simulation results show that both control solutions can keep the indoor pressure and the air circulation in a very satisfactory and robust manner, even subject to the presence of severe disturbances.

IEEE Press / 2014
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