Editorial

In our second issue for 2011, we will be publishing a total of 10 papers that reflect on a wide spectrum of sustainability issues. We start with a paper by Catarino et al. which proposes the concept of sustainable value based on a combination of the applications of cleaner production and value analysis. This is followed by a paper by Overcash and Twomey which presents an assessment of corporate sustainability programmes and identifies a model for long-term decision-making. We continue with a paper by Langella and Zanoni which has a supply chain theme. The authors propose a heuristic that obtains a Pareto-efficient frontier to enable managers of a distribution firm, with a network incorporating limited recovery, to identify the best solution to balance cost and environmental impact. The fourth paper, a case study by Gnoni et al., combines the themes of supply chain and alternative energy sources. It looks specifically at the green supply chain for the supply of biomass as an alternative energy source to assess the overall sustainability of an energy-generating facility.

The next two papers continue the alternative energy theme by addressing the use of bio-fuel as an alternative to diesel. That by Jindal evaluates the effect of injection timing on the combustion, performance and emissions of a small diesel engine running on pure bio-diesel produced from Karanj vegetable oil. In the paper by Banapurmath et al., it is the performance of engines fuelled with Honge and Jatropha oil methyl esters blended with ethanol that is the focus.

We next present two papers with a built-environment theme. The first, by Namagga and Atadero, evaluates the use of spray dryer ash as a replacement for Portland cement and the authors report promising results with between 25 and 35% replacement levels. On a somewhat different subject, Mallick et al. evaluate the potential for harvesting energy from asphalt pavements using piping networks with particular emphasis on cost effectiveness and payback period.

The final two papers are concerned with the efficiency of processes designed to remove emissions. That by Bandyopadhyay considers the redesign of a simple tapered bubble scrubber to remove fly-ash particulate, claiming to achieve almost 100% efficiency. In the paper by Al Momani et al., the effect that ozone has in a chemical sludge disintegration process was evaluated. The authors concluded that the settling ability of the sludge was faster at very low specific ozone doses and that sequential processing improved sludge settling tendency.