141 research outputs found

    Hydrothermal carbonization as an alternative sanitation technology: Process optimization and development of low-cost reactor

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    Background: The provision of safe sanitation services is essential for human well-being and environmental integrity, but it is often lacking in less developed communities with insufficient financial and technical resources. Hydrothermal carbonization (HTC) has been suggested as an alternative sanitation technology, producing value-added products from faecal waste. We evaluated the HTC technology for raw human waste treatment in terms of resource recovery. In addition, we constructed and tested a low-cost HTC reactor for its technical feasibility. Methods: Raw human faeces were hydrothermally treated in a mild severity range (≤ 200 °C and ≤ 1 hr). The total energy recovery was analysed from the energy input, higher heating value (HHV) of hydrochar and biomethane potential of process water. The nutrient contents were recovered through struvite precipitation employing process water and acid leachate from hydrochar ash. A bench-scale low-cost reactor (BLR) was developed using widely available materials and tested for human faeces treatment. Results: The hydrochar had HHVs (23.2 - 25.2 MJ/kg) comparable to bituminous coal. The calorific value of hydrochar accounted for more than 90% of the total energy recovery. Around 78% of phosphorus in feedstock was retained in hydrochar ash, while 15% was in process water. 72% of the initial phosphorus can be recovered as struvite when deficient Mg and NH 4 are supplemented. The experiments with BLR showed stable operation for faecal waste treatment with an energy efficiency comparable to a commercial reactor system. Conclusions: This research presents a proof of concept for the hydrothermal treatment of faecal waste as an alternative sanitation technology, by providing a quantitative evaluation of the resource recovery of energy and nutrients. The experiments with the BLR demonstrate the technical feasibility of the low-cost reactor and support its further development on a larger scale to reach practical implementation

    Sewage sludge treatment by hydrothermal carbonization : feasibility study for sustainable nutrient recovery and fuel production

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    Phosphorus recovery from waste biomass is becoming increasingly important, given that phosphorus is an exhaustible non-renewable resource. For the recovery of plant nutrients and production of climate-neutral fuel from wet waste streams, hydrothermal carbonization (HTC) has been suggested as a promising technology. In this study, digested sewage sludge (DSS) was used as waste material for phosphorus and nitrogen recovery. HTC was conducted at 200 °C for 4 h, followed by phosphorus stripping (PS) or leaching (PL) at room temperature. The results showed that for PS and PL around 84% and 71% of phosphorus, as well as 53% and 54% of nitrogen, respectively, could be recovered in the liquid phase (process water and/or extract). Heavy metals were mainly transferred to the hydrochar and only <1 ppm of Cd and 21–43 ppm of Zn were found to be in the liquid phase of the acid treatments. According to the economic feasibility calculation, the HTC-treatment per dry ton DSS with an industrial-scale plant would cost around 608 USD. Between 349–406 kg of sulfuric acid are required per dry ton DSS to achieve a high yield in phosphorus recovery, which causes additional costs of 96–118 USD. Compared to current sewage sludge treatment costs in Switzerland, which range between 669 USD and 1173 USD, HTC can be an economically feasible process for DSS treatment and nutrient recovery

    Weiterentwicklung der hydrothermalen Karbonisierung zur CO2-sparenden und kosteneffizienten Trocknung von Klärschlamm im industriellen Massstab sowie der Rückgewinnung von Phosphor

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    In Switzerland, sewage sludge has to be burned since 2006. So far the necessary drying was done by thermal methods with high inputs of energy. In this project we investigate hydrothermal carbonisation (HTC) as CO2 saving and cost efficient alternative to dry sewage sludge on industrial scale. The focus in this applied research project is on the process water treatment, the mechanical dewatering, the potential use of HTC coal, the recycling of phosphorus and heavy metals and an assessment of environmental effects of HTC compared to current treatments. The potential for biological decomposition was investigated in HTC process water and permeat, which was gained by membrane filtration of HTC process water. A medium to high decomposition rate was shown for organic matter in HTC process water and permeat by aerobic and anaerobic processes in batch experiments. In a continuous aerobic laboratory reactor the HTC process water and permeat showed decomposition rates of 70-75% for chemical oxygen demand (COD) at a specific load of 5-10 kg COD/(m3 reactor volume*d). In the competition for a HTC-stage at the Oftringen waste water treatment plant (WWTP) an increase of dissolved organic carbon (DOC) due to the addition of HTC-permeate is limited to 3 mg/l in the effluent of the WWTP. This value can be reached by an optimised membrane filtration with no further treatment for most cases. Advantages of HTC for the mechanical dewatering were shown with a filter press on industrual scale. HTC coal was successfully burned in mono- and mixed combustion plants on industrial scale, for example at Jura Cement in Wildegg or the sludge combustion plant (SVA) in Winterthur. At SVA additional fossil fuels could be temporarily fully substituted by HTC coal. Additional experiments on industrial scale are planned. No evidence of decreased recycling capability of phosphorus or heavy metals after carbonisation was found. Compared to the currently applied sewage sludge drying process the waste heat could be reduced by up to 62% and the electricity demand by up to 69% with HTC. A detailled life cycle assessment showed little differences of HTC compared to the thermal drying process with waste heat but significant advantages compared to the thermal process of drying with fossil fuels. HTC is most promising concerning minimal environmental effects if optimizing measures are applied such as the reduction of phosphorus and nitrogen in the HTC process water, the recycling of phosphorus and the use of lost heat, renewable energy sources such as sewage gas, wood chips, green electricity on adequate sites and if the produced HTC coal is used as substitute of fossil fuels, for example in cement industry or brown coal power plants. Currently a detailled technical study is prepared by AVA-CO2 and another competitor for the first industrial HTC plant in Switzerland to dry sewage sludge at the WWTP Oftringen

    PGRMC1: a new biomarker for the estrogen receptor in breast cancer

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    Estrogen receptor (ER) status is a critical biomarker in breast cancer, in large part because the ER is the target of tamoxifen and similar drugs. In the previous issue of Breast Cancer Research, Neubauer and colleagues used a proteomic approach to identify proteins that are differentially regulated by ER in breast tumors. The authors showed that ER-negative tumors have elevated levels of PGRMC1 (progesterone receptor membrane component-1), a hormone receptor component and binding partner for P450 proteins. In contrast, PGRMC1 was phosphorylated in ER-positive tumors. The staining patterns of ER and PGRMC1 were mutually exclusive in breast tumor sections, and PGRMC1 staining was sharply increased in hypoxic areas of the tumor. The results suggest that PGRMC1 is a candidate biomarker for ER status and hypoxia in breast cancer

    Why Do the Boreal Forest Ecosystems of Northwestern Europe Differ from Those of Western North America?

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    The boreal forest is one of the largest terrestrial biomes on Earth. Conifers normally dominate the tree layer across the biome, but other aspects of ecosystem structure and dynamics vary geographically. The cause of the conspicuous differences in the understory vegetation and the herbivore–predator cycles between northwestern Europe and western North America presents an enigma. Ericaceous dwarf shrubs and 3– to 4-year vole–mustelid cycles characterize the European boreal forests, whereas tall deciduous shrubs and 10-year snowshoe hare–lynx cycles characterize the North American ones. We discuss plausible explanations for this difference and conclude that it is bottom-up: Winter climate is the key determinant of the dominant understory vegetation that then determines the herbivore–predator food-web interactions. The crucial unknown for the twenty-first century is how climate change and increasing instability will affect these forests, both with respect to the dynamics of individual plant and animal species and to their community interactions

    GWAS Meta-Analysis of Suicide Attempt: Identification of 12 Genome-Wide Significant Loci and Implication of Genetic Risks for Specific Health Factors

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    Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors

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    Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe

    Digitalisierung beruflicher Lern- und Arbeitsprozesse. Impulse aus der Bauwirtschaft und anderen gewerblich-technischen Sektoren

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    Der Sammelband stellt aktuelle Ansätze zum digital unterstützten beruflichen Lernen dar. Die Beiträge geben Einblicke in die dynamische Entwicklung der Schnittstellen von Erwerbsarbeit und beruflicher Aus-, Fort- und Weiterbildung im Kontext der Digitalisierung Arbeits- und Lernmitteln. Der Band schließt damit an die 2019 ebenfalls im Universitätsverlag der Technischen Universität Berlin erschienene Publikation „Berufsbildung am Bau digital“ (hrsg. von Bernd Mahrin und Johannes Meyser) an. Das erste Kapitel erörtert grundsätzliche didaktische Fragen zu digital unterstütztem Lernen und Arbeiten einschließlich der Rahmenbedingungen. Im zweiten Kapitel schließen sich Beiträge zur Kapazitätsentwicklung, zu Standards und zu digitalen Werkzeugen an. Das dritte Kapitel widmet sich konkreten Einzellösungen mit starkem Praxisbezug und hohem Transferpotenzial zum digitalisierten Arbeiten und Lernen im Bausektor und im Metallbereich. Das abschließende vierte Kapitel präsentiert übergreifend nutzbare und frei zugängliche Online-Angebote wie einen Medienpool für Bildungszwecke, eine Lernmedien-Datenbank und ein hybrides Lernsystem mit virtuellem 3D-Gebäudemodell. Das Buch ist entstanden im Rahmen des durch das Bundesministerium für Bildung und Forschung und den Europäischen Sozialfonds geförderten Projektes DigiBAU – Digitales Bauberufliches Lernen und Arbeiten. (DIPF/Orig.)The anthology presents current approaches to digitally supported professional learning. The articles provide insights into the dynamic development of the interfaces between gainful employment and vocational training and further education in the context of digitization of work and learning aids. The volume is thus connected to the publication “Berufsbildung am Bau digital” (edited by Bernd Mahrin and Johannes Meyser), which was published in 2019 by the University Press of the Technische Universität Berlin. The first chapter discusses fundamental didactic questions about digitally supported learning and working, including the framework conditions. The second chapter picks contributions on capacity development, standards, and digital tools out as central themes. The third chapter is dedicated to concrete specific solutions with strong practical relevance and high transfer potential for digitized work and learning in the construction sector and in the metal sector. The final fourth chapter presents comprehensive and freely accessible online offers such as a media pool for educational purposes, a learning media database and a hybrid learning system with a virtual 3D building model. The book was created as part of the DigiBAU project - digital vocational learning and working in the field of construction - funded by the German Federal Ministry of Education and Research and the European Social Fund. (DIPF/Orig.
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