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In this study, SiC was deposited on carbon/carbon (C/C) composite substrate using chemical vapor deposition (CVD) method to investigate the kinetics of the deposition process. Therefore, the time, temperature, precursor composition (SiCl4:N2:CH4) and substrate position in the reactor were varied to evaluate the deposition rate. X-ray diffraction (XRD) method was used to characterize the phase composition and calculate the grain size and the texture coefficient of the coatings. Field emission scanning electron microscopy (FESEM) was utilized to observe the coating morphology, microstructure and thickness. As observed β-SiC was the dominant phase of the coating with varied preferred growth crystalline planes of (111), (220) or (311). The coating thickness was 2 µm and 5 µm for the samples treated at 1000 and 1100ºC, respectively.

This paper investigates the flexibility that exists within a dense phase carbon dioxide (CO2) pipeline system to accommodate upset conditions in the Carbon Capture and Storage (CCS) network by utilising the pipeline as a storage vessel whilst still maintaining flow into the pipeline. This process is defined in the pipeline industry as “line-packing” and the time available to undertake line-packing is termed the line-packing time. The longer the line-packing time, the more resilient the pipeline system is to flow variations or short term operational issues at the capture or storage site. The aims of the study were; to investigate the impact of typical CO2 pipeline design parameters (diameter, wall thickness and length) as well as CO2 mass flow rate and pipeline inlet and outlet pressure on the available line-packing time and; to derive relationships between the key variables to allow designers to optimise the line-packing time for a pipeline system. The study was undertaken by developing a viable study set of dense phase CO2 pipelines using steady state hydraulic analysis and stress based design principles. The study set was designed to cover the range of design parameters, flow rates and pressures considered to be typical of dense phase pipelines in CCS systems. For each of the pipelines in the study set, the line-packing time was calculated using a transient hydraulic analysis approach. Although by interrogating the results, individual relationships could be identified between key input parameters and the line-packing time, the integration of all of the critical parameters could not be achieved through simple regression analysis techniques. Consequently, using the dataset of pipelines and line-packing times developed, an Artificial Neural Network (ANN) was designed to enable a comprehensive sensitivity analysis of the line-packing time to the input data to be conducted. It is also demonstrated how the ANN can be used as a design tool for the prediction of line-packing time. As would be expected, the line-packing capacity of the pipeline can be increased by increasing the available internal volume of the pipeline, reducing the mass flow rate into the pipeline, increasing the allowable operating stress and managing the inlet pressure and outlet pressures. However, one of the key findings of the work is that, in the dense phase, line-packing times of only up to 8 hours can be achieved for pipeline dimensions typical of those considered for CCS schemes. Consequently it has been confirmed that the pipeline does not represent a long-term storage option for CCS systems. However, if line-packing capability is considered at the design stage then the level of flexibility for the pipeline to act as short-term storage in the network increases. In particular, it is recommended that the effect of increasing the wall thickness on the line-packing time is considered at the design stage to determine the benefits of this option in enabling the pipeline to be used as a short-term storage option in the CCS system and prevent venting of CO2 during short-term outage events at the capture or storage site.

Pipelines are acknowledged as one of the most efficient and cost-effective methods for transporting large volumes of various fluids over long distances and therefore the majority of proposed schemes for Carbon Capture and Storage (CCS) involve high pressure pipelines transporting carbon dioxide (CO2). In order to be able to design and route pipelines safely, it is a code requirement that a separation distance, or safety zone, is defined between the pipeline and any habitable dwellings along the route. Safety zones are generally defined on the basis of a Quantitative Risk Assessment (QRA). The purpose of a QRA is to assess the risks posed by a pipeline failure to people in the vicinity and to ensure that consistent levels of risk are applied along the pipeline route. The risk levels are normally calculated along a transect drawn perpendicular to the pipeline. These levels are then compared with defined acceptance criteria to determine the safety zone i.e. the distance from the pipeline within which the risk to the public from a pipeline failure is considered to be unacceptable. The calculation of the risk level requires the determination of both the probability of a failure occurring in the pipeline and the consequences of that failure to the population. For natural gas pipelines, existing and accepted QRA techniques can be implemented to define the consequences of failure based on the thermal hazards. However for CO2 pipelines, the consequences of failure need to be considered differently, as they relate to a toxic hazard rather than a thermal hazard. Therefore in order to conduct a consequence analysis, what is required is a determination of the concentration of CO2 to which an individual may be exposed during a release event. This type of data can be generated either using dispersion models. These models will produce a profile of the change in CO2 concentration with time at various distances from the release, see for example [1, 2], that can then be used in the QRA to determine the toxic dose and therefore the level of harm experienced by an individual. However, none of these approaches consider the effect of shelter on the dose experienced by an individual who is within a building at the time of the release or is outside and enters a building to seek shelter. The work described in this paper seeks to address this gap and describes the application of two models ̶ an analytical and a Computational Fluid Dynamics (CFD) model ̶ that can be used to determine the effects of shelter on the toxic dose received by an individual during a pipeline release event. The motivation behind this work was: i) to develop a validated and computationally efficient shelter model, which had been tested against experimental data and CFD models, ii) to use both CFD and analytical models to demonstrate how shelter should be considered as part of the QRA procedure for a CO2 pipeline. A description of the analytical model has been published previously [3]. Therefore, the current paper concentrates on an explanation of the development and application of the CFD model. Using a case study scenario for a single roomed building, engulfed by a transient cloud of CO2, comparisons are made between the output of the analytical models and the CFD models for the same scenario. A sensitivity analysis indicates the input parameters that most affect the resultant toxic effects within the building. The paper further demonstrates how both models can be extended to investigate the effects of partial coverage of the building with the cloud of CO2 and the impact of partitions within the building. Predictions of toxic dose are made for both models and it is demonstrated how these results can be used in a QRA analysis. This work has been funded by the UK Carbon Capture and Research Centre within the framework of the S-Cape project (Shelter and Escape in the Event of a Release of CO2 from CCS Transport Infrastructure UKCCSRC-C2-179). References [1] M. Molag, C. Dam, Modelling of accidental releases from a high pressure CO2 pipelines, in: 10th International Conference on Greenhouse Gas Control Technologies, Amsterdam, 2011, pp. 2301-2307. [2] J. Koornneef, M. Spruijt, M. Molag, A. Ramírez, W. Turkenburg, A. Faaij, Quantitative risk assessment of CO2 transport by pipelines - A review of uncertainties and their impacts, Journal of Hazardous Materials, 177 (2010) 12-27. [3] C.J.Lyons, J.M.Race, H.F.Hopkins, P Cleaver, Prediction of the consequences of a CO2 pipeline release on building occupants. in Hazards 25: Edinburgh International Conference Centre, Edinburgh; United Kingdom; 13 May 2015 through 15 May 2015. vol. 160, Institution of Chemical Engineers Symposium Series, Red Hook, Hazards 25, Edinburgh, 2015

Background: Controversy persists over the potential benefits/harms of opium consumption in coronary heart disease. This study investigated the association between 12 months’ major adverse cardiac events (MACE) and pre-procedural opium consumption among patients undergoing percutaneous coronary intervention (PCI). Methods: Retrospectively, 1545 consecutive men who underwent PCI between 21st June 2009 and 20th June 2010 at Tehran Heart Center and were registered in the PCI Databank were entered into this cohort study. The occurrence of MACE, defined as cardiac death, non-fatal myocardial infarction, and need for target vessel revascularization (TVR) or target lesion revascularization (TLR), was compared between two groups of opium consumers and non-consumers in 350 (22.7%) patients. Results: Sixty-four (0.86%) patients expired within 12 months. After adjustment for potential confounders, analysis revealed that opium consumption had no significant relationship with 12 months’ MACE [11(3.1%) vs. 53(4.4%); p value = 0.286, among opium users vs. non users, respectively].Furthermore, the different components of MACE, including target vessel revascularization, target lesion revascularization, coronary artery bypass graft, and non-fatal myocardial infarction, were not significantly related to opium use. Conclusion: Pre-procedural opium usage in patients undergoing PCI was not associated with 12 months’ MACE.

Horizontal location and interpretation of gravity anomalies plays an important role in the detection of anomalous bodies and determination of explorative boreholes location. There are various methods for interpreting of gravity anomalies, which commonly use high-pass filters. Among these, Normalized Full Gradient (NFG) method represents the full gradient of the gravity anomaly at a point divided by the average of the full gradient at the datum. This method uses Fourier series to remove deficiencies and eliminate the oscillations which appear on the downward continuation when passing through center of an anomalous body. In this paper, one hypothetical model is considered and a new method is presented to determine the optimum number of Fourier terms, which is used to calculate coefficient of Fourier terms (B-n) based on Filon technique. Then the B-n is used to calculate the NFG. On the vertical and horizontal cross-section maps of NFG, the closed maxima or minima can be used to estimate the depth to centers and horizontal location of mass of possible anomalous bodies (mineral or oil-gas bodies). To evaluate the NFG method, it is applied to the real field gravity data of a known reservoir, and the obtained results compared with the results of independent information arises from drilling and other geophysical methods. Comparison of the results show good agreement and clearly illustrates that the NFG method is able enough to locate anomalous bodies and estimate their burial depth precisely.

The impurities present in CO2 streams are extremely important for CO2 pipeline and ship transportation affecting, various aspects such as, the range of operation, safety considerations, fracture control, cracking, corrosion control, dispersion in the event of a release, fluid density, operating pressure, temperature and the quantity of CO2 that can be transported. The range and levels of potential impurities emitted from CO2 Capture facilities will differ between different power plant and industrial sources and also between the capture technologies installed at the source. However, the potential CO2 specifications that could enter the transport and storage systems, particularly from industrial sources, remain relatively under-researched. Therefore, it is of critical importance to improve the understanding of the effect of these potential impurities, which have not been widely studied, on CO2 compression, liquefaction and transportation in relevant conditions. IEAGHG has identified the need to study the effects of impurities in CO2 streams on CO2 compression, pipeline and shipping transportation. This study has been performed by a consortium led by Newcastle University and including the University of Edinburgh to address this need. The report: - Reviews the CO2 impurities that could be present from different CO2 capture technologies and develops twelve CO2 impurity scenario compositions for further analysis . - Evaluates these impurity scenarios for CO¬2 physical and transport properties. The properties that are investigated are the dew point, bubble point, melting point, density, Joule-Thomson coefficients, speed of sound, viscosity and thermal conductivity. Comprehensive tables and figures are provided for all of the scenarios investigated and for binary combinations of CO2 with impurity . - Evaluates the effects of the impurities on CO2 compression and liquefaction in terms of performance and energy requirements. - Identifies the effects of the impurities on the operating conditions for both pipeline and ship based transportation. - Evaluates the effect of the impurities on the selection of materials for pipeline and ship transportation.