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AbstractRegulations on automotive emissions are becoming increasingly stringent owing to the toxicity of gases like NOx, CO and unburned hydrocarbons. This brings the need for catalytic converters that convert the nitrogen oxides, CO and hydrocarbons to less harmful components. Steady state pseudo-homogeneous models for packed bed reactors have been developed earlier, taking into account the catalytic reduction of NO in the presence of CO. However, these models do not capture the transient behaviour of the reactor in real time systems. This project aims at developing a suitable transient model that is not computationally expensive but at the same time satisfactorily explains the behaviour of the converter at various operating conditions. The effect of the various operating parameters on the exit concentrations has also been studied. The major advantage of this system is that it takes into account the formation of N2O as an undesirable by-product, during the reduction of NO. It also captures the selectivity of N2 formation under various conditions, and is expected to be useful in predicting start-up emissions of the vehicle.

AbstractWhen discussing risk assessment and risk management related to Carbon Capture, transportation and Storage (CCS) the attention usually focuses on risk related to storage. However, planning and designing a CCS value chain will also require demonstrating the risk associated with carbon dioxide capture and transport is satisfactorily managed.Risk related to processing and transport of carbon dioxide is not a totally new aspect, but the amounts processed and contained as well as the physical state in which carbon dioxide will be handled is outside the boundaries of today's industrial application of carbon dioxide.As a project progresses from feasibility study via front end engineering to detail engineering, construction and finally commissioning and normal operation, the amount of input data for a risk assessment of course increases. It may thus be tempting to delay the safety risk assessment in the early stages as it can be done more accurately at a later stage. However, early identification of safety issues can usually enable those issues be resolved with much less impact to a project's budget and schedule and therefore this opportunity should not be lost. It should be noted that safety concerns are commonly cited in objections for CCS projects and therefore getting an early understanding of the safety risk will also help gain acceptance and support.This paper will present an evaluation of the typical level of risk assessment done in early phases of a CCS project, including a review of the risk analyses performed in the Front End Engineering and Design (FEED) for selected CCS projects. Moreover, experiences from the risk for carbon dioxide pipelines as well as processing and injection will be included.Challenges related to risk assessment at each stage in the project, from feasibility study to normal operation, will be discussed. Risk management measures, both of the preventive and of the consequence mitigating type, that should be included within a project risk assessment and evaluations, will also be included in the discussions.For the early stages the focus will be on how to identify hazards that may have a significant impact and/or be costly to mitigate at a later stage. The paper will focus on strengths and weaknesses of approaches and methods applied, and will provide guidance on their selection and use.As the project progresses, the attention will shift to managing the residual risk with the quantification and specification of design load requirements. For quantitative risk analysis the paper will give an overview of available risk analysis tools and their capabilities, with emphasis on modelling consequences of loss of containment.Loss of containment of carbon dioxide encompasses an extensive range of widely different scenarios. Most dispersion modelling tools will be capable of predicting the development of some scenarios, while other scenarios may represent a yet insurmountable challenge for one tool on its own. A range of predictable loss of containment scenarios will be presented, with an evaluation of the capabilities of selected tools for modelling these scenarios. Further, practical examples from quantitative risk analyses on supplementing integral dispersion models by computational flow dynamics models as well as simple calculations and available data will be given.

Abstract Laboratory experiments were carried out to study Schiff-base condensation reactions between amines and formaldehyde that occur on inlet lines of emission monitoring instruments. Primary amines and formaldehyde were found to quickly react on inlet surfaces to form the respective Schiff-base condensation products. Secondary and tertiary amines did not react with formaldehyde. Schiff-base condensation reactions between primary amines and formaldehyde were also observed to occur on the ∼110 m long inlet line that connects the absorber stack of the amine-based PCCC facility at Mongstad to the FT-IR and PTR-ToF-MS emission monitors. Emissions of primary amines and formaldehyde may be underestimated if condensation reactions of these species in inlet lines are not taken into account. The PTR-ToF-MS monitor does, however, also quantitatively detect the Schiff-base condensation products, making it straightforward to derive the correct amine and formaldehyde concentrations in the amine wash gas.

AbstractIn 2004 and 2005, the UK worked on carbon capture and storage (CCS) being included in the EU Emissions Trading Scheme (ETS). This develop ed monitoring and reporting guidelines (MRG) for capture, transpo rt and injection, wit h storage to be regulated under a separate framework. Since this was reported at GHGT8, some substantial developments from the European Commission (EC) have evolved, whi ch prompted further work by the UK. In particular this work has provided new MRG speci fically for geological storage sites, including for leakage from storage sites, and for enhanced oil recovery. T hese will be described. During this time, t he IPCC published its 2006 IPCC Guidelines for National Greenhouse Gas Inventories. The k ey methodolo gical principles for environmentally-sound CCS established in these guidelines should form the basis for EU ETS accounting, and these will be briefly described. In 2006/7 the EC issued revised M RG to cover Phase II of the EU ETS (2008-2012). These now required CCS projects to be ‘opted-in’ under a case-by-case approval process (Article 24). The UK government proceeded with an ‘opt-in’ applicatio n for a project nominated by the Carbon Capture and Storage Association (CCSA). The EC have now proposed to fully include CCS in the ETS for Phase III (from 2013) as described in the proposed ETS Directive (23 January 08). The EC have also established their own process to develop CCS MRG from the UK MRG (Nov 2007) and this is being reported separately by Groenenberg and Wartmann at GHGT9. So an evolving process for CCS in the EU ETS, but one which has helped to establish some fundamental principles for including CCS in an y emissions trading scheme.

AbstractCO2 storage monitoring programmes aim to demonstrate the effectiveness of the project in controlling atmospheric CO2 levels, by providing confidence in predictions of the long-term fate of stored CO2 and identifying and measuring any potentially harmful leaks to the environment. In addition, the EU Emissions Trading Scheme (ETS) treats leakages of stored CO2 from the geosphere in to the ocean or atmosphere as emissions, and as such they need to be accounted for. An escape of CO2 from storage may be detected through losses from the reservoir, or migration through the overburden, into shallow groundwater systems, through topsoil and into the atmosphere, or through a seabed into the water column. Various monitoring techniques can be deployed to detect and in some cases quantify leakage in each of these compartments. This paper presents a portfolio of monitoring methods that are appropriate for CO2 leakage quantification, with a view to minimising both uncertainties and costs.

AbstractVapor liquid equilibrium measurements were carried out in the temperature range 40 - 120̊C for aqueous 30% MEA solution for a fresh solution, solutions containing 0.24mol/kg artificial heat stable salts (HSS)(sulfate, acetate, formate); and solutions from pilot plant containing real HSS (of concentrations 0.12, 0.24 and 0.35mol/kg). All solutions are aqueous containing MEA of alkalinity 4.91mol/kg. The solutions gave similar CO2 partial pressures at a given temperature and CO2 loading. Solutions from pilot plant that contains MEA+real HSS showed somewhat increased CO2 partial pressure and were particularly slow to attain equilibrium. Existing VLE model for 30% MEA adequately represent the experimental data from fresh 30% MEA and 30% MEA+artificial HSS without any adjustment to the model. The existing model does not represent the VLE of 30% MEA+real HSS solution adequately. A correction factor of 1.3 applied to the pCO2 of the 30% MEA model was sufficient for adequate representation. The highly degraded level of the 30%MEA+real HSS solutions makes it unrealistic for a typical process. The solutions containing 30% MEA+artificial HSS mixture give a more realistic representation of liquid used in a typical process for CO2 capture; the VLE of these solutions is adequately represented by the existing model without adjustment.

AbstractThis work presents a wide literature survey of the available data of the experimental thermal conductivity data for organic liquids at the atmospheric pressure in the temperature range below normal boiling point and at saturation pressures for temperatures above the normal boiling point. The experimental data are collected for 136 pure compounds belonging to the following different families: refrigerant fluids, alkanes, alkenes, aromatics, cycloalkanes, cycloalkenes, ethers, esters, ketones, organic acids and alcohols. A reliable set of 4740 experimental data was finally selected. The range of temperatures and of thermal conductivity experimental values are analyzed and discussed. An equation for aromatic compounds is proposed. The equation is very simple and produces a noticeable improvement if compared with the existing equations.