Auswirkung einer Belüftung und Sickerwasserkreislaufführung auf den Austrag von Kohlenstoff und Stickstoff aus Deponien

The incorporation of MBT technologies in municipal solid waste (MSW) management has greatly changed the solid waste and landfill management. MBT not only significantly reduces the quantity of the output materials to be landfilled, but also reduces a considerable proportion of organic compounds and nutrients in the output materials, therefore, leading to a reductions of both gas and leachate emission potentials after the emplacement of such output materials on landfills. The main difference between leachates from MBT and MSW landfills is the low levels of organic carbon and ammonium in the MBT ones. Ammonium is regarded as the most problematic parameter in leachate from MSW landfills because it is normally present at high concentrations and persistent under anaerobic condition. Ammonium level in leachate from MBT landfills is much lower than that in leachate from MSW landfills, but is still relatively high compared to concentrations which are acceptable on the long term. Therefore, the treatment of leachate in the future is no longer or less focus on organic matter which has been dominant so far, rather on taking care of ammonium. A part of the study was about the effect of leachate recirculation on the characteristics of leachate from MBT residue and fresh MSW. The major part of the study focused on the effect of such recirculation combining with aeration on leachate quality of such waste materials. The lab-scale study results clearly showed that recirculation of leachate alone has little effect on the characteristics of leachates from both MBT residue and fresh MSW in the experimental duration. Meanwhile, such combination technique gives a remarkable influence on improving the quality of leachates from both types of investigated materials. Very high nitrogen removal efficiency (up to 99 %) was achieved by applying this combination technique to MBT residues, whereas organic carbon components were slightly affected. At the same time, the combination technique also has strong impacts on reduction of ammonium and organic carbon substances in the leachate from MSW. Though the combination technique results in considerable decreases of ammonium nitrogen in the leachates from both types of materials, the mechanism leading to such decreases is different. As for lab-scale lysimeters containing MBT residues, the study results indicated that nitrogen was lost via nitrification and denitrification processes by aeration. Meanwhile, the reduction of ammonium nitrogen in case of MSW was most likely due to the volatilisation of free ammonia. Despite such different mechanisms, the combination of in-situ aeration and leachate recirculation can be a simple and reliable measure to improve the quality of leachates from both MBT residue and MSW.Die Eingliederung der MBA-Technik in die Behandlung von Siedlungsabfällen hat die Deponiewirtschaft sowie die Behandlung fester Abfälle grundlegend verändert. Die MBA-Technik reduziert nicht nur die Menge an Output-Material, welche abgelagert wird, sie reduziert auch einen beträchtlichen Anteil an organischen Verbindungen und Nährstoffen. Dies bedeute, dass das Output-Material höher stabilisiert ist als das Input-Material. Dies hat als Ergebnis zur Folge, dass die möglichen Gasemissionen und die Sickerwasseremissionen nach der Ablagerung des Output-Materials reduziert werden. Der größte Unterschied zwischen Siedlungsabfalldeponien und Deponien auf denen MBA-Material abgelagert wurde, ist der, dass MBA-Material weniger organischen Kohlenstoff sowie Ammonium enthält. Ammonium wird als der problematischste Parameter im Sickerwasser aus Siedlungsabfalldeponien betrachtet, da er in hohen Konzentrationen und langlebig unter anaeroben Bedingungen auftritt. Die Ammoniumkonzentration im Sickerwasser aus einer MBA-Deponie ist viel geringer als die aus dem Sickerwasser einer Siedlungsabfalldeponie. Jedoch ist sie immer noch sehr hoch im Vergleich zu akzeptierten Konzentrationen in einer Langzeitbetrachtung. Aus diesem Grund ist die Betrachtung von organischen Materialien im Sickerwasser von geringerer Bedeutung. Viel wichtiger ist die Betrachtung des Problems mit Ammonium im Sickerwasser. Ein Teil der Studie war die Untersuchung der Effekte von Sickerwasserrückführung zur Charakterisierung von Sickerwasser aus MBA-Rückstand und frischem Siedlungsabfall. Der Hauptteil der Arbeit beschäftigt sich mit den Effekten einer solchen Rückführung sowie einer Belüftung zur Verbesserung der Sickerwasserqualität von Siedlungsabfällen. Die gewonnen Ergebnisse aus dem Labormaßstab zeigen deutlich, dass eine Rückführung des Sickerwassers alleine wenig Einfluss auf die Charakterisierung des Sickerwassers aus MBA-Rückstand und frischem Siedlungsabfall aufweist. Solch eine Kombinationstechnik hat einen bemerkenswerten Einfluss auf die Verbesserung der Qualität von Sickerwasser aus beiden untersuchten Materialien. Sehr hohe Wirkungsgrade der Stickstoffbeseitigung (bis zu 99,9 %) wurden durch die Anwendung dieser Kombinationstechnik für MBA-Rückstand erreicht. Organische Kohlenstoffverbindungen wurden demgegenüber nur leicht beeinflusst. Gleichzeitig hat diese Kombinationstechnik eine starke Auswirkung auf die Reduzierung von Ammonium und organischen Kohlenstoffverbindungen im Sickerwasser von Siedlungsabfällen. Obwohl die Kombinationstechnik zu einer beträchtlichen Abnahme von Ammoniumstickstoff im Sickerwasser aus beiden Materialien führt, ist der Mechanismus, welcher zu solch einer Abnahme führt ein anderer. Wie der Labormaßstab im Lysimeter mit MBA-Rückstand zeigt, ist die Reduktion durch eine Nitrifikation sowie Denitrifikation und eine Belüftung erfolgt. Dagegen ist die Reduktion von Ammoniumstickstoff bei Siedlungsabfall höchstwahrscheinlich durch der Verflüchtigung von freiem Ammoniak zustande gekommen. Trotz dieser unterschiedlichen Mechanismen, kann die Kombination von in-situ-Belüftung und einer Umwälzung des Sickerwassers eine einfache und zuverlässige Methode darstellen, um die Qualität des Sickerwassers aus MBA-Rückstand und Siedlungsabfall zu verbessern

Properties of Neutron Noise Induced by Localized Perturbations in an SFR

Investigation of the properties of neutron noise induced by localized perturbations in a sodium-cooled fast reactor has been performed using a multigroup neutron noise simulator. Three representations of the noise source associated with the perturbations of absorption, fission, and scattering cross sections, respectively, were assumed to be located at the first fuel ring around the central assembly. The energy- and space-dependent noise, that is, the amplitude and the phase, was calculated in a wide range of frequencies, for example, 0.1–100 Hz. The results show that in the important energy range (>1.0 keV) where the noise amplitude is significant the phase is almost constant with energy at the calculated frequencies despite the source types. At low frequencies, the variation of the phase is negligibly small at a large distance from the source. The perturbation in several fast groups has a significant contribution and dominates the amplitude and the phase of the induced noise

License Plate Recognition Based On Multi-Angle View Model

In the realm of research, the detection/recognition of text within images/videos captured by cameras constitutes a highly challenging problem for researchers. Despite certain advancements achieving high accuracy, current methods still require substantial improvements to be applicable in practical scenarios. Diverging from text detection in images/videos, this paper addresses the issue of text detection within license plates by amalgamating multiple frames of distinct perspectives. For each viewpoint, the proposed method extracts descriptive features characterizing the text components of the license plate, specifically corner points and area. Concretely, we present three viewpoints: view-1, view-2, and view-3, to identify the nearest neighboring components facilitating the restoration of text components from the same license plate line based on estimations of similarity levels and distance metrics. Subsequently, we employ the CnOCR method for text recognition within license plates. Experimental results on the self-collected dataset (PTITPlates), comprising pairs of images in various scenarios, and the publicly available Stanford Cars Dataset, demonstrate the superiority of the proposed method over existing approaches

Flexible Pavement Life Cycle Cost Analysis by Using Monte-Carlo Method and the Suggestions for Developing Countries

Flexible road pavement plays an essential role in developing an effective, economic, and safe operation road network of any country. In Vietnam, a developing country, the selection of a suitable flexible pavement structure is always a challenge due to fiscal limitations. The traditional determinant method (TDM) by which pavement structures are selected mainly on the basis of initial construction costs and traffic load has been used for many years in the nation. This paper presents the use of Monte Carlo simulation to analyze the entire flexible pavement life cycle cost. Data including initial and maintenance costs and road user costs were collected from several different types of existing flexible pavement in Nghe An province, Vietnam. Random variations of several main inputs were explored in order to develop density distribution functions. These functions then were used as the bases for Monte Carlo simulation. One million simulation runs were implemented and the Net Present Values (NPVs) among pavement types were compared under the light of risk analysis. Research results showed that TDM method provided bias and uncertain results compared to that of Monte Carlo one. In terms of long- term pavement performance, a low-cost pavement structure should not always be considered as a wise selection. Some other suggestions for a developing country as Vietnam were also included

Financial development, income inequality and institutional quality: A multi-dimensional analysis

Ambiguous impacts of financial development on income inequality in the literature imply that the impacts can be affected by other variables and may depend on different dimensions of financial development. This paper studies the effects of financial development with multi-dimensional analysis (financial depth, financial access and financial efficiency) of two main categories (financial institutions and financial markets) and institutional quality on income inequality in 30 Asian countries in the period 2000 – 2019. Results show that the financial institutions development (FI), the financial institutions access (FIA), the financial institutions efficiency (FIE), and the financial markets access (FMA) reduce income inequality; but the overall financial development (OFD), the financial markets development (FM), the financial institutions depth (FID), and the financial markets depths (FMD) increase it. Notably, better institutional quality not only lessens income inequality, but also moderates the effects of financial development on income inequality. Specifically, the improvement of institutional quality strengthens the beneficial effects of FI, FIA, FIE, and FMA on income inequality. Meanwhile, OFD, FM, FID, and FMD initially exacerbate income inequality until respective thresholds of institutional quality, and then beyond those levels of IQ, these indicators of financial development reduce income inequality. Results are robust with various estimators. These findings strongly support the importance of financial development with multi-dimensions and institutional reform in Asian countries as they have both direct and indirect impacts on income inequality through their mutual interactions

Ringhals Diagnostics and Monitoring, Annual Research Report 2015

This report gives an account of the work performed by the Division of Subatomic and Plasma Physics (former Division of Nuclear Engineering), Chalmers, in the frame of a research collaboration with Ringhals, Vattenfall AB, contract No. 630217-031. The contract constitutes a 1-year co-operative research work concerning diagnostics and monitoring of the BWR and PWR units. The work in the contract has been performed between January 1st 2015, and December 31st, 2015. During this period, we have worked with five main items as follows:1. Development of the mode separation model with an extension to describe 3-D core barrel vibrations;2. Analysis of new ex-core measurements, taken in R-4 after power uprate;3. Investigation of the correctness of the hypothesis that the reactivity component extracted from the ex-core detector signals can be due to fuel assembly vibrations with CORE SIM;4. A basic study in neutron noise theory which could provide some indirect support for the determination of the void fraction from neutron noise measurements;5. A preliminary study of the possibility of modelling 3-dimensional fuel assembly vibrations in a realistic PWR system with the CORE SIM simulator.This work was performed at the Nuclear Engineering Group of the Division of Subatomic and Plasma Physics, Chalmers University of Technology by Victor Dykin (project co-ordinator), Cristina Montalvo (visitor from the Technical University of Madrid), Hoai-Nam Tran (research collaborator from Duy Tan University), Imre P\ue1zsit and Henrik Nyl\ue9n, who was also the contact person at Ringhals

Ringhals Diagnostics and Monitoring, Annual Research Report 2016-17

This report gives an account of the work performed by the Division of Subatomic and Plasma Physics (formerly, Division of Nuclear Engineering), Chalmers, in the frame of a research collaboration with Ringhals, Vattenfall AB, contract No. 663628-054. The contract constitutes a 1-year co-operative research work concerning diagnostics and monitoring of the BWR and PWR units. The work in the contract has been performed between July 1st 2016, and December 31st, 2017. During this period, we have worked with six main items as follows:1. Further development and improvement of the coupled coarse-fine mesh CORE SIM-based model;2. Further investigation of the point-kinetic component of the noise induced by fuel assembly vibrations;3. Analysis of new ex-core measurements, taken in R-4 after power increase;4. Further development and test of the mode separation model as applied to 3-D “wobbling” type or “tilting” type core-barrel vibrations;5. A basic study in neutron noise theory which could provide some indirect support for the determination of the void fraction from neutron noise measurements;6. A pilot study of the possibility of using fission chambers for zero power noise experiments.The work was performed at the Nuclear Engineering Group of the Division of Subatomic and Plasma Physics, Chalmers University of Technology by Imre P\ue1zsit (project co-ordinator), CristinaMontalvo (visitor from the Technical University of Madrid), Hoai-Nam Tran (research collaborator from Duy Tan University, Vietnam), Omar Alejandro Olvera Guerrero (visitor, PhD student at UAM/Autonomus Metropolitan University, Mexico City, Mexico) and Henrik Nyl\ue9n, the contact person at Ringhals. The measurements reported in Chapter 6 were designed and executed by our collaborating partners in EPFL/PSI, Mathieu Hursin, Oskari Pakari and Vincent Lamirand