Band 28, Heft 4-6

Microbubble-based methods, in recent times, have been widely used for purification of water and wastewater. Microbubbles have several physicochemical properties, which make them eminently suitable for wastewater treatment. In this review, these properties have been analyzed in detail from the perspective of application. Various types of microbubble generators and their operation principles have been discussed. The transport of gas into the aqueous phase has been explained, and the correlations to predict the volumetric mass transfer coefficient have been presented. Many practical applications using ozone, oxygen and air microbubbles, some of which are currently at various stages of commercialization, have been presented. Other important uses of microbubbles for wastewater treatment, namely, removal of fine solid particulate matter and oil, have also been discussed. In addition, directions for future research of microbubble technology and their potential applications have been identified.

A review of up-to-date waste to energy technologies, their advances and improvements are presented in this paper. The focus is on waste incinerators under conditions of the European Union. Legislation overview, key equipment, ways of dealing with different process streams and tools for evaluating energy efficiency analysis are presented. The principles for maximum energy utilization are also formulated. A comparison of conventional and up-to-date performances of high efficiency flue gas cleaning systems illustrates the development of waste to energy technologies over the past decades.

Part 9 of the series Magnetic field assisted fluidization (MFAF) – a unified approach continues with separation processes addressing mechanical processing encompassing fluidization, sedimentation, deep bed filtration by magnetizable matrices, aerosol filtration, etc. The review refers not only to devices carrying out mechanical separations but also to basic physical phenomena controlling them such as particle aggregation (magnetic flocculation) and approaches to model them and correlate experimental data.

Investigations of metabolic uncouplers in growth systems such as activated sludge treatment are increasing because of their ability to decrease biomass growth. As of 2011, more than 10 metabolic uncouplers were reported to significantly decrease biomass yield by between 21% and 87%. In this paper, we present a detailed review of metabolic uncoupling, different metabolic uncouplers, current applications in waste water treatment systems and their possible use in biological air pollution control systems such as biofiltration in order to improve the substrate degradation rate. This paper will be useful for those who are interested in using metabolic uncouplers to improve the performance of growth or non-growth systems.