Biogas : opportunities to improve safety and safety regulation

The production of biogas is positioned as energy which can not only generate a source of renewable energy but also which recycles waste. In the context of sustainable development, the place of biogas is therefore essential. Several questions about safety issues, the harmonization of the regulations and the need to develop standards are discussed in this paper, based on the results of a workshop on biogas safety and regulation organized in November 2010 and the activities of the European Working Group on Biogas Safety and Regulation created after the workshop. The risks corresponding to the biogas production and use have been framed using iNTeg-Risk method and tools. Several defi cits for risk management have been identifi ed and a strategy to improve risk management proposed by the working group is presented at the end of the paper

In situ sensors for measurements in the global trosposphere

Current techniques available for the in situ measurement of ambient trace gas species, particulate composition, and particulate size distribution are reviewed. The operational specifications of the various techniques are described. Most of the techniques described are those that have been used in airborne applications or show promise of being adaptable to airborne applications. Some of the instruments described are specialty items that are not commercially-available. In situ measurement techniques for several meteorological parameters important in the study of the distribution and transport of ambient air pollutants are discussed. Some remote measurement techniques for meteorological parameters are also discussed. State-of-the-art measurement capabilities are compared with a list of capabilities and specifications desired by NASA for ambient measurements in the global troposphere

Instrumentation and control of anaerobic digestion processes: a review and some research challenges

The final publication is available at Springer via http://dx.doi.org/10.1007/s11157-015-9382-6[EN] To enhance energy production from methane or resource recovery from digestate, anaerobic digestion processes require advanced instrumentation and control tools. Over the years, research on these topics has evolved and followed the main fields of application of anaerobic digestion processes: from municipal sewage sludge to liquid mainly industrial then municipal organic fraction of solid waste and agricultural residues. Time constants of the processes have also changed with respect to the treated waste from minutes or hours to weeks or months. Since fast closed loop control is needed for short time constant processes, human operator is now included in the loop when taking decisions to optimize anaerobic digestion plants dealing with complex solid waste over a long retention time. Control objectives have also moved from the regulation of key variables measured online to the prediction of overall process perfor- mance based on global off-line measurements to optimize the feeding of the processes. Additionally, the need for more accurate prediction of methane production and organic matter biodegradation has impacted the complexity of instrumentation and should include a more detailed characterization of the waste (e.g., biochemical fractions like proteins, lipids and carbohydrates)andtheirbioaccessibility andbiodegradability characteristics. However, even if in the literature several methodologies have been developed to determine biodegradability based on organic matter characterization, only a few papers deal with bioaccessibility assessment. In this review, we emphasize the high potential of some promising techniques, such as spectral analysis, and we discuss issues that could appear in the near future concerning control of AD processes.The authors acknowledge the financial support of INRA (the French National Institute for Agricultural Research), the French National Research Agency (ANR) for the "Phycover" project (project ANR-14-CE04-0011) and ADEME for Inter-laboratory assay financial support.Jimenez, J.; Latrille, E.; Harmand, J.; Robles Martínez, Á.; Ferrer Polo, J.; Gaida, D.; Wolf, C.... (2015). Instrumentation and control of anaerobic digestion processes: a review and some research challenges. Reviews in Environmental Science and Biotechnology. 14(4):615-648. doi:10.1007/s11157-015-9382-6S615648144Aceves-Lara CA, Latrille E, Steyer JP (2010) Optimal control of hydrogen production in a continuous anaerobic fermentation bioreactor. 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Artificial olfaction system for on-site odour measurement

Odour impacts and concerns are an impediment to the growth of the Australian chicken meat industry. To manage these, the industry has to be able to demonstrate the efficacy of its odour reduction strategies scientifically and defensibly; however, it currently lacks reliable, cost effective and objective tools to do so. This report describes the development of an artificial olfaction system (AOS) to measure meat chicken farm odour. This report describes the market research undertaken to determine the demand for such a tool, the development and evaluation of three AOS prototypes, data analysis and odour prediction modelling, and the development of two complementary odour measurement tools, namely, a volatile organic compound (VOC) pre-concentrator and a field olfactometer. This report is aimed at investors in poultry odour research and those charged with, or interested in, assessment of odour on chicken farms, including farm managers, integrators, their consultants, regulators and researchers. The findings will influence the focus of future environmental odour measurement research

A model-based control concept for a demand-driven biogas production

With the expansion of highly fluctuating renewable energies (like wind power and photovoltaics) in the last few years, the intelligent integration of these new energy sources into the German energy system is becoming one of the central challenges. Biogas plants can play a key role in this transition. The present thesis investigates the possibilities, underlying mechanisms and dependencies establishing a flexible biogas production by means of demand-driven feeding. Furthermore, a robust control concept for demand-driven operation has to be developed and demonstrated in full-scale.Mit dem Ausbau von fluktuierenden erneuerbaren Energien (Windkraft, Photovoltaik) und dem voraussichtlichen Weiterschreiten dieser Entwicklung wird die intelligente Integration dieser Energiequellen in das Energiesystem zur zentralen Herausforderung. Biogasanlagen besitzen dabei eine Schlüsselrolle. Die vorliegende Dissertation untersucht die Möglichkeiten, zugrundeliegende Mechanismen und Abhängigkeiten zur Etablierung einer flexiblen Biogasproduktion durch bedarfsgesteuerte Fütterung. Es ist ein robustes Regelungskonzept entwickelt und im großtechnischen Maßstab demonstriert worden

Improving Low-Cost Measurement Techniques to Investigate the Connections Between Fossil Fuels and Air Quality: from Oil and Gas Production to Home Heating

Natural gas, as an energy resource can exert both positive and negative influences on air quality where people live, work, and go to school. Air quality in basins where oil and gas are produced from geologic formations can be potentially degraded by industry activities, but using natural gas in place of solid fuels like wood and coal for home heating and in other applications can potentially result in improved air quality. Low- cost gas sensors have emerged recently with great potential to help inform air quality on the scales that people live in ways that traditional instrumentation is not well suited, though the usefulness of these tools is complicated by cross sensitivity to environmental variables like temperature and humidity, as well as potentially confounding gas species. The ability of low-cost gas sensors to yield meaningful information about air quality, with relevance to human and environmental health, is therefore contingent on progress in terms of sensor signal quantification methods, best practices for experimental design and deployment, along with data quality assessment and interpretation.In this dissertation, such methods are developed and applied, employing low-cost gas sensors to characterize air quality in both indoor and ambient environments, in the context of natural gas production and end use as a home heating fuel. Carbon monoxide (CO) measurements are used to characterize how home heating fuels can differentially influence air quality in homes on the Navajo Nation. CO levels in homes are quantified with uncertainty estimation and are employed to estimate air exchange rates in homes and CO emission rates. Methods to measure air quality in oil and gas production basins using arrays of low-cost gas sensors are also developed and analyzed. Field normalization sensor signal quantification methods employing both artificial neural networks and multiple linear regressions are compared. The sensitivity and robustness of each quantification method is explored for each gas species. To further understand how distributed grids of sensor measurements can inform spatial and temporal patterns of air quality in oil and gas production basins, the performance of these sensor quantification methods are assessed when extended to new sampling locations