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Abstract: A finite model was established to predict the radiation field around a line lamp treating contaminated air, taking into account the effects of the radius of the lamp and sleeve, as well as other physical parameters. Both irradiance and fluence rate could be calculated, and the model was validated with measured data and by comparison with a conventional extense source volumetric emission (ESVE) model. Diffuse and specular emissions for a line lamp were compared, showing that diffuse emission is more appropriate for a low pressure mercury UV lamp. Refraction by the lamp sleeve can induce a 12% increase in fluence rate near the sleeve, while reflection causes a 7% decrease. When the attenuation coefficient of a gaseous chemical is less than 0.04m−1 the error due to ignoring its light absorption is less than 1%, within a distance of 0.2m from the lamp. [Copyright &y& Elsevier]

A mathematical model describing the performance of photocatalytic reactors was proposed, and fitted using data for 4-chlorophenol degradation collected with a flat plate reactor. It was used to predict the performance of corrugated plate photocatalytic reactors, and this was then compared with subsequent experimental results. With only three experimentally determined parameters, the new model incorporates reaction kinetics, mass transfer, and photon transfer. The model-predicted performance of the corrugated plate reactors, with different structural parameters and under different hydrodynamic and illumination conditions, was found to agree with the experimental data reasonably well. [Copyright &y& Elsevier]

• Power input to the liquid was measured using electrical current and voltage. • Rocking action results in a periodic power curve, best characterized by peak power. • Mass transfer coefficient (k L a) is related to peak power input via a power law model. • Rocking bioreactor power inputs of up to 800 W/m3 are achievable. The impact of specific power input on gas-liquid mass transfer and mixing has not been extensively reported for rocking disposable bioreactors. An electrical method was applied for measuring the specific power input into a disposable rocking (Wave) bioreactor at benchtop scales. The peak power input was shown to be suitable for characterizing the impact of operational parameters including rocking frequency, rocking angle and liquid volume. The average power inputs ranged from 66.5 W/m3 to 680.1 W/m3 which were comparable to those for stirred tank and orbitally-shaken disposable bioreactors. The gas-liquid oxygen mass transfer coefficient was shown to correlate with the peak power input in a power law model, confirming that the mass transfer capacity rapidly increased with power input, especially at 600 W/m3 and greater. The correlation between mixing time and power input indicated that power input at higher than 400 W/m3 was sufficient to induce relatively rapid mixing. [ABSTRACT FROM AUTHOR]