Sustainability evaluation of the use of cargo-trams for mixed municipal waste transport in Prague.

The use of trams for the transport of waste from urban areas to waste incineration facilities - does it make sense, would it be technically feasible, economically sustainable and environmentally beneficial? These are the questions which we attempted to answer in this comprehensive study. The analysis is performed for a specific potential implementation of this system in Prague and adjacent municipalities. In this work, we compare the current state, where mixed municipal waste is transported to an incineration plant directly by garbage trucks, with variants if mixed municipal waste were taken to transfer stations and from there transported over a longer distance in a large volume by means of tram or truck. Our results show that use of trams results in an overall cost level of €16.41 per ton of waste transported, which represents a slight saving against the existing system at a cost of €17.19 per ton. From the purely economic perspective, however, this does not compete with transportation by truck at €12.28 per ton - above all due to high initial investment into new cargo trams. From the environmental viewpoint, deploying trams brings benefits largely on the local level, where emissions would be reduced by about 50% against the current state. In the global view, assessed through the Life Cycle Assessment method, it appears however only to transfer emissions to the point of energy production, and from this perspective the use of trams is beneficial only if linked with a notable shift from fossil fuel energy to nuclear or renewable sources.

Life cycle assessment comparison of photocatalytic coating and air purifier.

This article presents a comparison of 2 very different options for removal of undesirable microorganisms and airborne pollutants from the indoor environment of hospitals, schools, homes, and other enclosed spaces using air purifiers and photocatalytic coatings based on nano titanium dioxide (TiO2 ). Both products were assessed by life cycle assessment (LCA) methodology from cradle-to-grave. The assessment also includes comparison of 2 different nano TiO2 production technologies, one by continuous hydrothermal synthesis and the other by a sulfate process. Results of the study showed a relatively large contribution of photocatalytic coatings to reducing the effects of selected indices in comparison with an air purifier, regardless of which nano TiO2 production method is used. Although the impacts of the sulfate process are significantly lower compared to those of hydrothermal synthesis when viewed in terms of production alone, taken in the context of the entire product life cycle, the net difference becomes less significant. The study has been elaborated within the Sustainable Hydrothermal Manufacturing of Nanomaterials (SHYMAN) project, which aims to develop competitive and sustainable continuous nanoparticle (NP) production technology based on supercritical hydrothermal synthesis. Integr Environ Assess Manag 2016;12:478-485. © 2016 SETAC.