95 research outputs found

    Benefits of ecological engineering practices

    Get PDF
    With the intention to further promote the field of ecological engineering and the solutions it provides, a workshop on “Benefits of Ecological Engineering Practices” was held 3 December 2009. It was conducted by the International Ecological Engineering Society in Paris at the conference “Ecological Engineering: from Concepts to Application” organized by the Ecological Engineering Applications Group GAIE. This paper presents the results of the workshop related to three key questions: (1) what are the benefits of ecological engineering practices to human and ecosystem well-being, (2) which concepts are used or useful to identify, reference, and measure the benefits of ecological engineering practices, and (3) how and to whom shall benefits of ecological engineering practices be promoted. While benefits of ecological engineering practices are diverse, general conclusions can be derived to facilitate communication. Identifying benefits requires valuation frameworks reaching beyond the scope of ecology and engineering. A distinction between human and ecosystem well-being in this regard may not be easy or useful, but instead humans embedded in ecosystems should be addressed as a whole. The concepts of resource efficiency, ecosystem services, ecosystem health, and multifunctional land use could serve as suitable references to frame ecological engineering benefits, as well as referring to international political goals such as biodiversity protection, climate change mitigation and poverty reduction. Sector and application specific criteria of good practice could be worked out. Regional, area specific reference systems for sustainable development could provide comparative advantages for ecologically engineered solutions. Besides people with high decision making power and people with high motivation for change are good target groups to be addressed

    Energy dissipation via acoustic emission in ductile crack initiation

    Get PDF
    The final publication is available at Springer via http://dx.doi.org/10.1007/s10704-016-0096-8.This article presents a modeling approach to estimate the energy release due to ductile crack initiation in conjunction to the energy dissipation associated with the formation and propagation of transient stress waves typically referred to as acoustic emission. To achieve this goal, a ductile fracture problem is investigated computationally using the finite element method based on a compact tension geometry under Mode I loading conditions. To quantify the energy dissipation associated with acoustic emission, a crack increment is produced given a pre-determined notch size in a 3D cohesive-based extended finite element model. The computational modeling methodology consists of defining a damage initiation state from static simulations and linking such state to a dynamic formulation used to evaluate wave propagation and related energy redistribution effects. The model relies on a custom traction separation law constructed using full field deformation measurements obtained experimentally using the digital image correlation method. The amount of energy release due to the investigated first crack increment is evaluated through three different approaches both for verification purposes and to produce an estimate of the portion of the energy that radiates away from the crack source in the form of transient waves. The results presented herein propose an upper bound for the energy dissipation associated to acoustic emission, which could assist the interpretation and implementation of relevant nondestructive evaluation methods and the further enrichment of the understanding of effects associated with fracture

    Application of Ligninolytic Enzymes in the Production of Biofuels from Cotton Wastes

    Get PDF
    The application of ligninolytic fungi and enzymes is an option to overcome the issues related with the production of biofuels using cotton wastes. In this dissertation, the ligninolytic fungus and enzymes were evaluated as pretreatment for the biochemical conversion of Cotton Gin Trash (CGT) in ethanol and as a treatment for the transformation of cotton wastes biochar in other substances. In biochemical conversion, seven combinations of three pretreatments (ultrasonication, liquid hot water and ligninolytic enzymes) were evaluated on CGT. The best results were achieved by the sequential combination of ultrasonication, hot water, and ligninolytic enzymes with an improvement of 10% in ethanol yield. To improve these results, alkaline-ultrasonication was evaluated. Additionally, Fourier Transform Infrared (FT-IR) and principal component analysis (PCA) were employed as fast methodology to identify structural differences in the biomass. The combination of ultrasonication-alkali hydrolysis, hot liquid water, and ligninolytic enzymes using 15% of NaOH improved 35% ethanol yield compared with the original treatment. Additionally, FT-IR and PCA identified modifications in the biomass structure after different types of pretreatments and conditions. In thermal conversion, this study evaluated the biodepolymerization of cotton wastes biochar using chemical and biological treatments. The chemical depolymerization evaluated three chemical agents (KMnO4, H2SO4, and NaOH), with three concentrations and two environmental conditions. The sulfuric acid treatments performed the largest transformations of the biochar solid phase; whereas, the KMnO4 treatments achieved the largest depolymerizations. The compounds released into the liquid phase were correlated with fulvic and humic acids and silicon compounds. The biological depolymerization utilized four ligninolytic fungi Phanerochaete chrysosporium, Ceriporiopsis subvermispora, Postia placenta, and Bjerkandera adusta. The greatest depolymerization was obtained by C. subvermispora. The depolymerization kinetics of C. subvermispora evidenced the production of laccase and manganese peroxidase and a correlation between depolymerization and production of ligninolytic enzymes. The modifications obtained in the liquid and solid phases showed the production of humic and fulvic acids from the cultures with C. subvermispora. The results of this research are the initial steps for the development of new processes using the ligninolytic fungus and their enzymes for the production of biofuels from cotton wastes

    Bodemleven, organische stof en eco-engineering

    No full text

    A sustainable built environment: A new text book based on ecosystem theory

    No full text
    With half of the world population living in urban areas and with the building sector as the largest industrial sector in the US and Europe, the built environment makes a significant contribution to sustainability problems, in terms of energy use, material extraction, waste production and land conversion. In a search for a common theoretical basis as foundation for the chosen multi-perspective approach, ecosystem theory appeared to be a powerful framework. A transdisciplinary team of teachers and researchers from different faculties and institutes of the Delft University of Technology joint their efforts to write a text book for master students from different disciplines. The book gives insights in important sustainability effects of the built environment and of leading methods and tools to assess and address these problems at various spatial scales: ranging from the building level to the urban plan. It also deals with the specific institutional context of the built environment and its influence on the innovation and implementation of sustainable technologies. The paper goes f into the basis for this book, which is the ecosystem theory and how it was applied on 13 fields relevant to the subject: ecosystems, urban ecology, water flows, materials, energy, air quality, livability, urban transport, urban forms, strategies and tools for sustainability, integrated solutions, governance and transition management.Technology, Policy and Managemen
    • …
    corecore