José Potting

Environmental Comparison of Biobased Chemicals from Glutamic Acid with Their Petrochemical Equivalents

Glutamic acid is an important constituent of waste streams from biofuels production. It is an interesting starting material for the synthesis of biobased chemicals, thereby decreasing the dependency on fossil fuels. The objective of this paper was to compare the environmental impact of four biobased chemicals from glutamic acid with their petrochemical equivalents, that is, N-methylpyrrolidone (NMP), N-vinylpyrrolidone (NVP), acrylonitrile (ACN), and succinonitrile (SCN). A consequential life cycle assessment was performed, wherein glutamic acid was obtained from sugar beet vinasse. The removed glutamic acid was substituted with cane molasses and ureum. The comparison between the four biobased and petrochemical products showed that for NMP and NVP the biobased version had less impact on the environment, while for ACN and SCN the petrochemical version had less impact on the environment. For the latter two an optimized scenario was computed, which showed that the process for SCN can be improved to a level at which it can compete with the petrochemical process. For biobased ACN large improvements are required to make it competitive with its petrochemical equivalent. The results of this LCA and the research preceding it also show that glutamic acid can be a building block for a variety of molecules that are currently produced from petrochemical resources. Currently, most methods to produce biobased products are biotechnological processes based on sugar, but this paper demonstrates that the use of amino acids from low-value byproducts can certainly be a method as well.

Environmental life cycle assessment of Ethiopian rose cultivation

A life cycle assessment (LCA) was conducted for Ethiopian rose cultivation. The LCA covered the cradle-to-gate production of all inputs to Ethiopian rose cultivation up to, and including transport to the Ethiopian airport. Primary data were collected about materials and resources used as inputs to, and about the product outputs from 21 farms in 4 geographical regions (i.e. Holleta, Sebeta, Debre Ziet, and Ziway). The primary data were imported in, and analyzed with the SimaPro7.3 software. Data for the production of used inputs were taken from the EcoInvent®2.0 database. Emissions from input use on the farms were quantified based on estimates and emission factors from various studies and guidelines. The resulting life cycle inventory (LCI) table was next evaluated with the CML 2 baseline 2000 V2/world, 1990/characterization method to quantify the contribution of the rose cultivation chain to 10 environmental impact categories. The set of collected primary data was comprehensive and of high quality. The data point to an intensive use of fertilizers, pesticides, and greenhouse plastic. Production and use of these inputs also represent the major contributors in all environmental impact categories. The largest contribution comes from the production of the used fertilizers, specifically nitrogen-based fertilizers. The use of calcium nitrate dominates Abiotic Depletion (AD), Global Warming (GW), Human Toxicity (HT) and Marine Aquatic Ecotoxicity (MAET). It also makes a large contribution to Ozone Depletion (OD), Acidification (AD) and Fresh water Aquatic Ecotoxicity (FAET). Acidification (AC) and Eutrophication (EU) are dominated by the emission of fertilizers. The emissions from the use of pesticides, especially insecticides dominate Terrestrial Ecotoxicity (TE) and make a considerable contribution to Freshwater Aquatic Ecotoxicity (FAET) and Photochemical Oxidation (PhO). There is no visible contribution from the use of pesticides to the other toxicity categories. Production and use of greenhouse plastic are another important contributors, and just a bit less than the contribution of calcium nitrate to Abiotic Depletion (AD). The results of this study clearly indicate nutrient management and emissions from pesticide use, especially insecticides, as a focus point for environmental optimization of the rose cultivation sector in Ethiopia.

Comparison of different methods to include recycling in LCAs of aluminium cans and disposable polystyrene cups

Many methods have been reported and used to include recycling in life cycle assessments (LCAs). This paper evaluates six widely used methods: three substitution methods (i.e. substitution based on equal quality, a correction factor, and alternative material), allocation based on the number of recycling loops, the recycled-content method, and the equal-share method. These six methods were first compared, with an assumed hypothetical 100% recycling rate, for an aluminium can and a disposable polystyrene (PS) cup. The substitution and recycled-content method were next applied with actual rates for recycling, incineration and landfilling for both product systems in selected countries. The six methods differ in their approaches to credit recycling. The three substitution methods stimulate the recyclability of the product and assign credits for the obtained recycled material. The choice to either apply a correction factor, or to account for alternative substituted material has a considerable influence on the LCA results, and is debatable. Nevertheless, we prefer incorporating quality reduction of the recycled material by either a correction factor or an alternative substituted material over simply ignoring quality loss. The allocation-on-number-of-recycling-loops method focusses on the life expectancy of material itself, rather than on a specific separate product. The recycled-content method stimulates the use of recycled material, i.e. credits the use of recycled material in products and ignores the recyclability of the products. The equal-share method is a compromise between the substitution methods and the recycled-content method. The results for the aluminium can follow the underlying philosophies of the methods. The results for the PS cup are additionally influenced by the correction factor or credits for the alternative material accounting for the drop in PS quality, the waste treatment management (recycling rate, incineration rate, landfilling rate), and the source of avoided electricity in case of waste incineration. The results for the PS cup, which are less dominated by production of virgin material than aluminium can, furthermore depend on the environmental impact categories. This stresses the importance to consider other impact categories besides the most commonly used global warming impact. The multitude of available methods complicates the choice of an appropriate method for the LCA practitioner. New guidelines keep appearing and industries also suggest their own preferred method. Unambiguous ISO guidelines, particularly related to sensitivity analysis, would be a great step forward in making more robust LCAs.

Facility arrangements and the environmental performance of disposable and reusable cups

PurposeThis paper integrates two complementary life cycle assessment (LCA) studies with the aim to advice facility managers on the sustainable use of cups, either disposable or reusable. Study 1 compares three disposable cups, i.e., made from fossil-based polystyrene (PS), biobased and compostable plastic (polylactic acid; PLA) and paper lined with PLA (biopaper). Study 2 compares the disposable PS cup with reusable cups that are handwashed or dishwashed.MethodsExisting LCA studies show inconsistent and sometimes conflicting results, due to differences in used data and modeling choices. The comparison of disposable cups, study 1, deliberately applied multiple inventory data sets for relevant life cycle processes and multiple crediting principles for recycling. Included waste treatment options in study 1 were incineration, recycling, composting, and anaerobic digestion (last two not for the disposable PS cup). The PS cup is next compared with handwashed and dishwashed reusable cups (study 2). LCAs for the reusable cups use single data sets, and explore the influence of an increasing number of reuses. Cup LCA results were only compared within, and not across impact categories. All data relate to cups used with hot beverage vending machines in Dutch office settings.Results and discussionImpact results for each disposable cup show large and overlapping spreads. This prevents identifying a preferable disposable cup material, though still allows cautious preferences about waste treatment processes. Composting biocups is less good than other waste treatment processes. Average impact results for anaerobic digestion perform in almost all impact categories better than incineration for the PLA cup. Average impact results for recycling perform slightly better than incinerating for both biocups, but not for the PS cup. This comparison is affected, however, by the relatively large credits for avoided Dutch electricity production. Impact results for reusable cups do not perform better than disposable cups if both are used once. Impact results for the reusable cups contain large uncertainty due to widely varying user behavior.ConclusionsOverall results do not allow any preference for one of the disposable cups or for disposable versus reusable cups. All cups can be used for more than one consumption. This gives a considerable environmental gain for the second and third hot beverage consumption with all cups. Facility managers can encourage a second or third serving with the same cup by financial incentives, only putting on dishwashers around noon and after working time, and/or consumer awareness activities.

Advancing energy efficient early-stage vehicle design through inclusion of end-of-life phase in the life cycle energy optimisation methodology

Environmentally-friendly energy-efficient vehicles are an important contributor to meet future global transportation needs. To minimise the environmental impact of a vehicle throughout its entire life cycle, the life cycle energy optimisation (LCEO) methodology has been proposed. Using the proxy of life cycle energy, this methodology balances the energy consumption of vehicle production, operation and end-of-life scenarios. The overall aim is to design a vehicle where life cycle energy is at a minimum. While previous work only included vehicle production and operation, this paper aims at advancing the LCEO methodology by including an end-of-life phase. A simplified design study was conducted to illustrate how vehicle design changes when end-of-life treatment is included. Landfilling, incineration and recycling have been compared as end-of-life treatments, although the focus was put on recycling. The results reveal that the optimal design not only changes with the inclusion of an end-of-life phase but it changes with specific end-of-life treatment.