Karel Van Acker

Cost-efficient emission abatement of energy and transportation technologies: Mitigation costs and policy impacts for Belgium

In the light of global warming, this paper develops a framework to compare energy and transportation technologies in terms of cost-efficient GHG emission reduction. We conduct a simultaneous assessment of economic and environmental performances through life cycle costing and life cycle assessment. To calculate the GHG mitigation cost, we create reference systems within the base scenario. Further, we extend the concept of the mitigation cost, allowing (i) comparision of technologies given a limited investment resource, and (ii) evaluation of the direct impact of policy measures by means of the subsidized mitigation cost. The framework is illustrated with a case of solar photovoltaics (PV), grid powered battery electric vehicles (BEVs), and solar powered BEVs for a Belgian small and medium sized enterprise. The study’s conclusions are that the mitigation cost of solar PV is high, even though this is a mature technology. The emerging mass produced BEVs on the other hand are found to have a large potential for cost-efficient GHG mitigation as indicated by their low cost of mitigation. Finally, based on the subsidized mitigation cost, we conclude that the current financial stimuli for all three investigated technologies are excessive when compared to the CO2 market value under the EU Emission Trading Scheme.

Environmental and economic performance of plasma gasification in Enhanced Landfill Mining

This paper describes an environmental and economic assessment of plasma gasification, one of the viable candidates for the valorisation of refuse derived fuel from Enhanced Landfill Mining. The study is based on life cycle assessment and life cycle costing. Plasma gasification is benchmarked against conventional incineration, and the study indicates that the process could have significant impact on climate change, human toxicity, particulate matter formation, metal depletion and fossil depletion. Flue gas emission, oxygen usage and disposal of residues (plasmastone) are the major environmental burdens, while electricity production and metal recovery represent the major benefits. Reductions in burdens and improvements in benefits are found when the plasmastone is valorised in building materials instead of landfilling. The study indicates that the overall environmental performance of plasma gasification is better than incineration. The study confirms a trade-off between the environmental and economic performance of the discussed scenarios. Net electrical efficiency and investment cost of the plasma gasification process and the selling price of the products are the major economic drivers.

Downcycling versus recycling of construction and demolition waste: Combining LCA and LCC to support sustainable policy making

Urgent solutions are needed in Europe to deal with construction and demolition waste (CDW). EU policy has contributed to significantly reducing the amount of CDW going to landfill, but most of the effort has been put in downcycling practices. Therefore, further policies are needed to stimulate high-quality recycling of CDW. The present paper presents a combined life cycle assessment (LCA) and life cycle costing (LCC) methodologies to analyse the environmental and the economic drivers in four alternative CDW end-of-life scenarios in the region of Flanders, in Belgium. The four analysed alternatives are (i) landfilling, (ii) downcycling, (iii) advanced recycling and (iv) recycling after selective demolition. LCA results show that landiflling is the scenario having the highest environmental impacts in terms of person equivalent (PE), followed by downcycling and recycling (-36%) and recycling after selective demolition (-59%). The decrease in environmental impacts is mostly due to the avoided landfilling of CDW and the recovery of materials from selective demolition. LCC results indicate that landfilling is the scenario bearing the highest total economic costs. This is due to the high landfill tax in Flanders. The recycling after selective demolition bears the second highest cost. The increase of high-quality CDW recycling can significantly reduce the overall environmental impact of the system. Implementing a high landfill tax, increasing the gate fee to the recycling plant, and boosting the sales price of recycled aggregates are the most effective drivers to facilitate a transition towards a more sustainable CDW management system. The paper demonstrates that the combined LCA and LCC results can highlight the environmental and economic drivers in CDW management. The results of the combined analysis can help policymakers to promote the aspects contributing to sustainability and to limit the ones creating a barrier.

EU-Average Impacts of Wheat Production: A Meta-Analysis of Life Cycle Assessments

Wheat is an important commodity in Europe. With a production of 133 million tonnes per year and annual import and export accounting for 6.3 and 5.3 billion US

Construction Materials from Stainless Steel Slags: Technical Aspects, Environmental Benefits, and Economic Opportunities

, respectively, wheat is the most important cereal in Europe. Wheat cultivation further feeds into a wide variety of products ranging from bread, over imitation meat, to biofuels and bio‐based materials. Therefore, it is desirable to have a synthetic life cycle assessment (LCA) of the impacts of an average kilogram (kg) of wheat produced in Europe. This article aims to provide such a synthesis using two strategies. In the first strategy, we give an overview of published LCA impacts of wheat production. A second strategy is a meta‐analysis in which a re‐evaluation is made of 20 available life cycle inventories representing cases in 11 different European countries. Based on the production shares of these countries in the total European production, weighted average impacts are calculated. These weighted averages of the re‐evaluated inventories show that an average kg of wheat grain produced in Europe demands 3.25 megajoules of nonrenewable, fossil energy, emits 0.61 to 0.65 kg carbon dioxide equivalents, triggers terrestrial acidification of 4.94 to 6.51 grams (g) sulphur dioxide equivalents, freshwater eutrophication of 0.08 to 0.09 g phosphorous equivalents, marine eutrophication of 4.97 to 7.60 g nitrogen equivalents, and occupies 1.63 square meter years of agricultural land. The re‐evaluation of studies results in similar impacts as the mere reviewing of energy demands and global warming potentials. Given the many applications of wheat, the presented meta‐analysis is interesting to evaluate the average and range of environmental performance of wheat production in Europe, but is also useful as an input in assessing impacts of wheat‐based products.

Evolution of Residual Micro Phase and Orientation Dependent Stresses during Cold Wire Drawing

State‐of‐the‐art technologies that implement the industrial ecology concept only make it to the market if environmental gains and economic benefits are significant. Therefore, the article investigates, in an interdisciplinary way, two innovative technologies that valorize stainless steel (SS) slags as block masonry (bricks): carbonation and thermo‐alkali‐activation. The technical, environmental, and economic features of three SS bricks - solid bricks, perforated bricks, and lightweight aerated blocks - are compared to commercially available construction materials. Although the produced bricks meet industrial standards, technical challenges, such as optimization of alkali addition and use of metal molds, should be dealt with before upscaling to industrial production. A cradle‐to‐gate life cycle assessment that aggregates the results of the various impact categories shows that the environmental impact of solid and perforated SS bricks is lower than the impact of conventional clay‐baked bricks owing to the avoidance of additives for slag stabilization and energy consumption for sintering clay. The impact of aerated SS bricks was found to be similar to the commercially available aerated blocks. More specifically, the carbon dioxide uptake from carbonation reduces the overall environmental impact, whereas use of alkalis increases the impact. A strengths weaknesses opportunity threats analysis highlights the economic advantages of SS bricks originating from lower energy requirements, reduced dependence on primary resources, and improved metal recovery from slag. However, in order to apply the innovative technologies at industrial scale, challenges related to processing conditions, feedstock variability, and potential competition from existing brick suppliers have to be overcome.

Gas-solid reaction kinetics of ZnFe2O4 formation from 907 to 1100 °C

The residual grain and phase microstress evolutions in the ferrite matrix of pearlitic wires after several steps of cold wire drawing have been studied. Energy dispersive synchrotron diffraction revealed a significant divergence in the grain microstress evolution among differently oriented ferrite grains in the high deformation regime beyond accumulated true strain level εt ≥ 2.3.The possible physical reason for the observed divergence is discussed in terms of distinct microstructure development in this stage of the cold wire drawing.

Environmental Assessment of Printed Circuit Boards from Biobased Materials

The reaction kinetics of Zn vapor with Fe3O4 (magnetite) were studied from 907 to 1100 °C using a new experimental setup that only allows contact between the reactants through a gas-solid reaction. Hematite was used to create the reaction pellets. Because of the reducing atmosphere in the setup, a magnetite layer is formed on the outside of the pellet, which in turn reacts with the Zn vapor. After reaction, Zn concentration profiles were measured in the reacted magnetite layer using field-emission gun electron probe microanalysis. The reaction was confirmed to be diffusion-controlled. The effect of both volume and grain-boundary diffusion was observed in each experiment. The temperature dependence of both the volume and grain-boundary diffusion coefficients was obtained along with the activation energies of the diffusion coefficients. This study provides crucial information for the development of technologies that are dependent on the reaction. One example is the in-process separation technology for the separation of Zn vapor from electric arc furnace off-gas.

Laser dispersing of ceramic powders into Al-alloys

This paper performs a cradle-to-gate LCA (Life Cycle Assessment) to compare the environmental impact between conventional PCB substrate (epoxy resins reinforced with glass fiber) and biobased PCB substrate, in case epoxidized linseed oil and flax fiber. The study reveals that the overall weighted environmental scores of substrate from biobased materials are significantly lower than the traditional materials, especially in impact categories of climate change, human toxicity and fossil resources depletion. Since previous results showed satisfactory technical properties of the biobased materials as PCB substrate, they offer promising perspectives for final replacement of the conventional materials.

Life cycle assessment to evaluate the environmental performance of new construction material from stainless steel slag

The general objective of the work was formation of highly wear resistant metal matrix composite (MMC) surface layers on aluminium based Al 6061 alloy by means of laser dispersing. The surface of the substrate is locally melted by the high power diode laser beam and simultaneously powder particles are injected into molten material. The optimal process parameter window for the laser dispersing of SiC in Al 6061 has been found. The measured values of the wear rates of the sample with dispersed SiC particles are about seven times lower than that of the reference Al-substrates. Results show that laser dispersing is highly promising technology to improve the surface, mainly wear properties of light metals. However the possibilities of industrial application are still limited due to considerable laser beam power and preheating temperature applied as well low productivity because of low scanning speed, and therefore further investigations are required.