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In this work a novel Monte Carlo method is developed to simulate the equilibrium thermodynamic properties of strongly associating fluids. The highly anisotropic nature of intermolecular interactions in these fluids makes conventional simulation techniques of little use. By introducing biased sampling techniques we are able to explore configuration space efficiently, thereby obtaining reliable estimates for the thermodynamic properties, including phase equilibria, of model systems. The results of our simulations are used to assess the accuracy and validity of various theories for associating fluids. [ABSTRACT FROM AUTHOR]

The deployment of a complete carbon capture and storage chain requires a focus upon the hazards posed by the operation of pipelines transporting carbon dioxide (CO2) at high pressure in a dense-phase (supercritical or liquid state). The consequences of an intentional or accidental release from such pipelines must be considered as an integral part of the design process. There are a number of unique challenges to modelling these releases due to the unusual phase-transition behaviour of CO2. Additionally, few experimental observations of large-scale CO2 releases have been made, and the physics and thermochemistry involved are not fully understood. This work provides an overview of elements of the EC FP7 CO2PipeHaz project, whose overall aim is to address these important and pressing issues, and to develop and validate mathematical models for multiphase discharge and dispersion from CO2 pipelines. These are demonstrated here upon a full-scale pipeline release scenario, in which dense-phase CO2 is released from a full-bore 36-in. pipeline rupture into a crater, and the resulting multiphase CO2 plume disperses over complex terrain, featuring hills and valleys. This demonstration case is specifically designed to illustrate the integration of different models for the pipeline outflow, near-field and far-field dispersion. [ABSTRACT FROM AUTHOR]

The problem of simultaneous biodegradation of two dissimilar substrates in a continuously operated cyclic reactor was studied both at the theoretical and experimental levels using a simple model system. The system involved media containing mixtures of glucose and phenol as carbon sources. A pure culture of Pseudomonas putida (ATCC 17514) was employed. Independent kinetic experiments have revealed that glucose and phenol are involved in a crossinhibitory uncompetitive kinetic interaction. The dynamics of a cyclically operated reactor were analyzed using the principles of bifurcation theory for forced systems. Experimental results have confirmed the theoretical predictions. Implications of the results for the design of waste-treating facilities are discussed.