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Abstract: An evaluation was performed on the efficiency and emissions from an engine fuelled with compressed natural gas (CNG) and a mixture of natural gas and hydrogen, respectively. The mixtures of CNG and hydrogen were named HCNG. Two different mixtures were investigated; pure CNG, and 29vol% H2 in CNG (named HCNG). For each mixture, four engine speeds were tested under full load conditions. For each mixture and each engine speed four different excess air ratios (λ) were chosen. The lean limit for the pure CNG tested in this engine is approximately , and the lean limit for the HCNG is even leaner, i.e. at about . This is as expected, and in accordance with the literature. Considering the total emissions of unburned hydrocarbons and nitrogen oxides, it is easily seen that the positive effect of adding hydrogen to the CNG increases as a function of lambda. By adding hydrogen to CNG, an increase in power will result in the λ investigated. The efficiency for HCNG is greater than for CNG for the same λ, and the difference in η th,brake between HCNG and CNG for the same λ increases with increasing excess air ratio. [Copyright &y& Elsevier]

The transboundary transportation of carbon dioxide (CO2) gives rise to international legal issues not faced in other standalone carbon capture and storage (CCS) projects or domestic projects. While the European Union CCS Directive establishes a framework for CCS, it does not address specifically the issue of transboundary transportation. This will require participating Member States to agree a statutory framework for CO2 transport, which addresses issues at the international, national and local levels of law. This paper considers several key issues for developing and resolving legal issues around ownership and risk for CO2 transportation, an area with limited research literature to date. The legal challenges are examined using a ‘pilot’ project to explore and highlight specific examples. The research draws from a series of CCS industry stakeholder meetings and analysis was developed through interdisciplinary perspectives. In addition, the potential partnership arrangements are explored from a law and policy perspective with an examination of the key issues for these partnerships for Member States. Finally, this research presents a timeline for a legal strategy on resolving the issues for risk and ownership for CO2 transport. [ABSTRACT FROM AUTHOR]

Abstract: SINTEF Energy Research and the Norwegian University of Science and Technology – NTNU have proposed a 150kWth reactor system design aiming at further development of chemical looping processes. It consists of a double loop circulating fluidized bed, meant to be used as a platform to study atmospheric chemical looping combustion configurations, as well as other possible chemical looping processes e.g. gas turbine combustion and reforming. The hydrodynamic viability of the design needs to be tested by means of a cold flow model, operated without chemical reactions. An evaluation of the state of the art within cold flow model testing was done. It led to the choice of building a full scale (i.e. 1:1) cold model of the 150kWth hot rig design, in order to reduce wall-effects which have considerably larger influence at smaller reactor diameters than on larger ones. The cold flow model was extensively tested and experimental results are presented. The aimed design condition, mirroring a chemical looping combustion process adapted to steam generation, was achieved successfully and in a stable way. The performance of the reactor system was further tested in off-design conditions to define operational guidelines for the hot operation. In addition, attempts were done to resemble other chemical looping processes, getting some understanding of how the reactor system may perform and consequently providing solid hydrodynamic bases to improve the design for those applications. In all cases, stable operational sets were found in order to satisfy the cold flow model hydrodynamic requirements consistently with the actual high temperature processes. [Copyright &y& Elsevier]