Gassco AS

Norway

Gassco AS

Norway
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Tejedor J.,University of Alcalá | Martins H.F.,FOCUS S.L. | Piote D.,FOCUS S.L. | Macias-Guarasa J.,University of Alcalá | And 6 more authors.
Journal of Lightwave Technology | Year: 2016

This paper presents the first available report in the literature of a system aimed at the detection and classification of threats in the vicinity of a long gas pipeline. The system is based on phase-sensitive optical time-domain reflectometry technology for signal acquisition and pattern recognition strategies for threat identification. The system operates in two different modes: 1) machine+activity identification, which outputs the activity being carried out by a certain machine; and 2) threat detection, aimed at detecting threats no matter what the real activity being conducted is. Different strategies dealing with position selection and normalization methods are presented and evaluated using a rigorous experimental procedure on realistic field data. Experiments are conducted with $\text{eight}$ machine+activity pairs, which are further labeled as threat or nonthreat for the second mode of the system. The results obtained are promising given the complexity of the task and open the path to future improvements toward fully functional pipeline threat detection systems operating in real conditions. © 1983-2012 IEEE.

Grant
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ENERGY.2008.5.2.2 | Award Amount: 2.42M | Year: 2009

This project aims at paving the road towards large-scale, Europe-wide infrastructure for the transport and injection of CO2 from zero-emission plants. The project will prepare for the optimum transition from initial small-scale, local initiatives towards large-scale CO2 transport and storage that is to start around 2020, with key stakeholders in the field of carbon capture, transport and storage. This transition, as well as the development of CO2 infrastructure will be studied by developing the business case in a number of realistic scenarios. The project will result in a roadmap for CO2 transport infrastructure, with 2020 as the target year for start of large-scale CCS in Europe. The roadmap will be defined for all levels considered in the project, ranging from technical to organizational, financial and societal.

Munkejord S.T.,Sintef | Bernstone C.,Vattenfall | Clausen S.,Gassco AS | De Koeijer G.,Statoil | Molnvik M.J.,Sintef
Energy Procedia | Year: 2013

The present paper concerns the importance of a combined modelling and experimental effort to develop physicsbased combined thermodynamic and transient flow models for CO2-transport pipelines. Such models need to handle both multiple components and two-phase flow, which can occur both during normal operation and transient situations, such as first fill and depressurization. Moreover, these models can provide useful input to risk analyses and design of mitigation actions of undesirable incidents like pipeline rupture and well blow-outs. This paper discusses various physical phenomena, design issues and solutions by using the experience from actual cases encountered by Vattenfall, Gassco and Statoil. Among the key issues are the minimum temperature in the pipe wall during depressurization and the magnitude of pressure oscillations during transient operation.

Grant
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2013.2.2 | Award Amount: 6.27M | Year: 2013

PETROBOT will open the oil-, gas and petrochemical markets by developing two key new robot inspection technologies and validating these in use cases:1. Off-line internal inspection of pressure vessels: avoiding the high cost for human entry as well as reducing plant down-time.2.In-line inspection of storage tanks: avoiding lost revenue by keeping tanks in full operation.Currently, inspections are carried out by human inspectors. Plants must be taken out of operation inducing substantial lost revenue and shut down costs. Recent robot developments are promising, but technologies have not been adapted to the requirements of the target sectors.PETROBOT mobilises the complete value chain consisting of robot- and inspection technology providers, inspection service companies and end users in order to develop innovative inspection robots and validate these solutions in use cases. Innovative aspects include:1. Improved navigation and mobility capability and autonomy of robots.2. Adaptation of inspection technologies to robot usage.3. Integration of robot and inspection technology components and software development that specifically meet the sectors needs.4. Demonstration and validation of the solutions in real field.In order to accelerate deployment of validated solutions substantial attention will be paid to:- integration aspects (operations, safety, cleaning and inspection procedures, adaptation of plant for robot acces, inspection standards);- establishing deployment potential;- investigating market uptake routes.Main impacts are:1. Opening of new markets for robot inspection (hardware and services: 300 mln/year).2. Cost reductions through reduced shut-down times and inspection related costs. Savings for industries using pressure vessels and storage tanks are estimated at 350 mln/year.3. Stimulation of innovation in robotics and robot inspection services.4. Reduction of exposure of personnel to hazards related to confined space entry.

Helgaker J.F.,Polytec Research Institute | Helgaker J.F.,Norwegian University of Science and Technology | Oosterkamp A.,Polytec Research Institute | Oosterkamp A.,Norwegian University of Science and Technology | And 2 more authors.
Journal of Natural Gas Science and Engineering | Year: 2014

Transportation of natural gas through high pressure large diameter offshore pipelines is modeled by numerically solving the governing equations for one-dimensional compressible pipe flow using an implicit finite difference method. The pipelines considered have a diameter of 1m and length of approximately 650km. The influence of different physical parameters which enter into the model are investigated in detail. These include the friction factor, equation of state and heat transfer model. For high pressure pipelines it is shown that the selection of the equation of state can have a considerable effect on the simulated flow results, with the recently developed GERG 2004 being compared to the more traditional SRK, Peng-Robinson and BWRS equations of state. Also, including heat accumulation in the ground is important in order to model the correct temperature at the outlet of the pipeline. The flow model is validated by comparing computed results to measured values for an offshore natural gas pipeline. © 2013 Elsevier B.V.

Clausen S.,Polytec | Oosterkamp A.,Polytec | Strom K.L.,Gassco AS
Energy Procedia | Year: 2012

We describe the results of depressurizing an onshore 50 km long, 24 inches buried pipeline from initially supercritical conditions. The event has been simulated using OLGA, a multi-phase pipeline simulation tool, recently adapted to handle single components like CO2. The simulated results deviate from the measurements during the two-phase release period. The obtained results suggest that small amounts of impurities matter, even at concentration as low as 1 Mole %. In addition, the simulated onset of boiling and the mass transfer rate between the liquid and gaseous phase is not supported by the experiments. © 2012 The Authors. Published by Elsevier Ltd.

Dugstad A.,Institute for Energy Technology of Norway | Clausen S.,Gassco AS | Morland B.,Institute for Energy Technology of Norway
NACE - International Corrosion Conference Series | Year: 2011

Both field experience and lab data indicate that the corrosion rate in pure dense phase CO2 is near zero if no free water is present. It is not confirmed that this also applies when other contaminants like SOx, NOx, H 2S and O2 are present in moderate amounts. In a pipeline network with different type of CO2 sources, the comingling of streams with various impurities can give a very complex mixture, and side reactions like oxidation and decomposition of impurities can be foreseen. An important issue is how the contaminants partition between the various phases during pressure reduction and when free water is present. The corrosion mechanisms under these conditions are not very well understood and it becomes more and more uncertain what will happen when the concentration of contaminants including water increases. The paper addresses these issues and discusses recent results obtained in corrosion and partitioning experiments carried out in flow loops and autoclaves. © 2011 by NACE International.

Dugstad A.,Institute for Energy Technology of Norway | Halseid M.,Institute for Energy Technology of Norway | Morland B.,Institute for Energy Technology of Norway | Sivertsen A.O.,Gassco AS
Energy Procedia | Year: 2013

When dense phase CO2 is depressurised and forms a two phase gas/liquid system, impurities will partition between the two phases and go preferentially to the phase where their solubility is highest. Partitioning and depressurisation experiments run at 4 and 25 °C showed that water, H2S and SO2 accumulated while O2 was depleted in the remaining liquid CO2 phase when the system was depressurised via the gas phase. When the water solubility is exceeded, a third aqueous phase can form. The accumulation of impurities increased the corrosivity of the remaining liquid phase and carbon steel specimens exposed in the autoclaves were corroded after 3 days exposure. Lowest corrosion rates (< 0.1 mm/year) were measured in a system with CO 2 and water (489 and 1222 ppmv) only. The corrosion rate is reasonably low because the water phase quickly becomes saturated with corrosion products that reduce the corrosivity. The situation was different when the CO2 contained SO2 (138 ppmv) and NO2 (191ppmv) as these gases accumulate in the water phase, reduce the pH and increase the reactivity of the aqueous phase. The specimens in the SO2 experiments got covered with a black film and the corrosion rates were about 0.1 mm/year while the specimens in the NO2 experiment developed a brown rusty layer of corrosion products and the corrosion rate was about 1 mm/year. These high corrosion rates only last until the impurities are consumed, the replenishment and availability of impurities becomes therefore an important issue. The accumulation of impurities (including water) was maximum 5- 10 times the original concentration in the experiments where the liquid phase was reduced to 10-20 % of the original volume. The ratio of the remaining to the original liquid phase volume can be much lower in a long pipeline and a much larger accumulation can be foreseen. If the corrosion rate consumes most of the available impurities in the pipeline, the corrosion rate can be much higher than the corrosion rate measured in the present experiments.

Clausen S.,Gassco AS | Munkejord S.T.,Sintef
Energy Procedia | Year: 2012

A numerical benchmark study has been performed, comparing results from the OLGA pipeline simulator to data obtained using the multi-stage (MUSTA) centred scheme. The case considered is a depressurization of a pipeline. Care was taken to compare the same flow model and thermodynamic equation of state. The two methods appear to converge on fine grids, but on coarse grids, the MUSTA method is more accurate. © 2012 The Authors. Published by Elsevier Ltd.

Dugstad A.,Institute for Energy Technology of Norway | Morland B.,Institute for Energy Technology of Norway | Clausen S.,Gassco AS
Energy Procedia | Year: 2011

Both field experience and lab data indicate that the corrosion rate of carbon steel in pure dense phase CO2 is near zero if no free water is present. The question is whether this also applies when other contaminants like SOx, NOx, H2S and O2 are present in moderate amounts. In a pipeline network with different types of CO2 sources, the commingling of streams with various impurities can give a very complex mixture, and side reactions like oxidation and decomposition of impurities can be foreseen. An important issue is how the contaminants partition between the various phases during pressure reduction and when free water is present. The corrosion mechanisms under these conditions are not well understood, and it becomes more and more uncertain what will happen when the concentration of contaminants including water increases. The paper addresses these issues and discusses recent corrosion flow loops and autoclaves results obtained in an ongoing sub-sea CO2 transmission pipeline project. © 2010 Published by Elsevier Ltd. © 2011 Published by Elsevier Ltd.