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This Master Thesis project is focused on Life Cycle Analysis (LCA) of retrofit solutions for brake emission and the comparison of each solution. Background research was performed to check possible solutions to the Particulate Matter (PM) problem that non-exhaust emissions contribute to. Then four main scenarios were created, based on surface treatment by laser cladding and the addition of a filtration device: the reference brake, laser cladded brake, reference brake with filtration and laser cladded brake with filtration. Each scenario was then analyzed by using a life cycle analysis. The analysis was done with the help of ECO Audit tool which is a part of GrandaEdu pack software. After acquiring the results, a desirability function method was used in order to assess and compare each scenario. The result has shown that some solutions might be feasible, with an overall desirability increase of 55% compared to the original reference brake system. Such solutions include the laser cladded brake with the 1 kg filtration device and the filtration medium change once every two brake pads. Detta examensarbete är fokuserat på streamlined (LCA) av eftermonteringslösningar för bromsutsläpp och jämförelse av varje lösning. Bakgrundsforskning utfördes för att kontrollera möjliga lösningar på partikelproblemet (PM) som icke-avgasutsläpp bidrar till. Därefter skapades fyra huvudscenarier, baserade på ytbehandling med laser behandlig och tillägg av en filtreringsanordning: referensbromsen, laserklädd broms, referensbroms med filtrering och laserklädd broms med filtrering. Varje scenario analyserades sedan med hjälp av en livscykelanalys. Analysen gjordes med hjälp av ECO Audit-verktyget som är en del av GrantaEdu pack mjukvara. Efter att ha inhämtat resultaten användes en sammanvägningsfunktion för att bedöma och jämföra varje scenario. Resultatet har visat att vissa lösningar kan vara genomförbara, med en övergripande ökning på 55 % efter sammanvägningsanalysen jämfört med det ursprungliga referensbromssystemet. Sådana lösningar inkluderar den laserklädda bromsen med 1 kg-filtreringsanordningen och filtermediet byts varannan gång då bromsbelägg byts.

Both the EU and China are evaluating the feasibility of lowering the detection limit of particle number (PN) measurement to 10 nm in future legislations, making it necessary to better understand the sub-23 nm particle emission characteristics from state-of-the-art vehicles. In this study, solid PN emissions with a diameter larger than 10 nm and 23 nm (known as SPN10 and SPN23) were compared over the WLTC, RTS95, and a so-called “worst-case” real driving emission (RDE) cycle (highly dynamic/0 °C) using two certification-level particle number counters (PNCs) employing evaporation tube (ET) and catalytic stripper (CS) as volatile particle remover (VPR). The results show that SPN10 emissions were 31.7%, 27.8%, and 15.2% higher than SPN23 over the WLTC, RTS95, and laboratory RDE cycles. Sub-23 nm particles were almost not identified within the engine cold-start phase and tended to be a hot-running pollutant favored by aggressive driving styles (frequent accelerations and high engine loads), fuel-cut during decelerations, and long idles. Lower testing temperature delayed the light-off of catalyst and, therefore, significantly reduced the formation of sub-23 nm particles within the engine warm-up stage. Lowering the detection limit to 10 nm is deemed to provide more public health protection since it will guide manufacturers to pay more attention to vehicle hot-running emissions.

In this article, in order to optimize diesel aftertreatment system with periodically reciprocating flow (PRF), an experimental study is conducted to investigate its characteristics such as pollution emissions, regeneration of diesel particulate filter (DPF), concentration, and size distribution of particulate matter (PM) escaped as well as temperature distribution under unidirectional flow and PRF operating conditions. The effects of reciprocating flow cycle and exhaust gas flow on the performance of aftertreatment system are investigated in detail. The energy efficiency analysis of the aftertreatment system is also carried out. Experimental results show that (a) as the temperature is lower than the light‐off threshold of combustible gas, the aftertreatment system cannot restrain the formation of second particles under the low‐temperature condition of unidirectional flow; and (b) the aftertreatment system demonstrates excellent performance of trapping particles and filter regeneration as the symmetrical temperature distribution is formed. The PM filter efficiency αPM is 92%, and the specific energy consumption β is 124% for symmetrical temperature distribution; (c) the increase in reciprocating flow cycle could lead to the shifting of the temperature profiles, and this would affect the particle size distribution; (d) a certain increase in exhaust gas flow from engine would have insignificant change for the temperature distribution; and (e) the critical energy efficiency ηc of the system could reach 96.61%.

The emission of particulate matter (PM) from agricultural activities, such as concentrated animal feeding, straw combustion, and mechanized harvest, is a hot issue in the sustainable development of agriculture, which has attracted more and more attention from government departments and researchers. However, the research on the transport of particulate matter in the agri-environment still lacks flexible and efficient measurement methods to obtain real-time and accurate spatial distribution data. The objective of our study is to produce a new intelligent platform for agri-environment atmospheric monitoring with high mobility, temporal and spatial resolution, and remote data transmission function to overcome the shortcomings of traditional atmospheric particulate matter monitoring stations, such as small particle size range, immovability, and high cost. Through the light scattering sensor, microcontroller, and wireless data transmission device assembled on the high-mobility drone, the platform could measure the mass concentration of PM2.5, PM10, and TSP at different spatial points in the agri-environment and transmit the measurement data to the receiving device on the ground through three modes: CLOUD, TCP, and UDP. We also developed monitoring software based on the Android platform, which could complete the connection of device and real-time monitoring of measurement data on the ground. Compared with stationary measurement devices, the biggest advantage of our mobile monitoring system is that it has the ability to measure the concentration of TSP and the vertical distribution of PM, which is very important for the research of agricultural environmental particulate matter emission characteristics. After the sensor and communication performance experiments, the sensors had high consistency in the overall change trend, and the communication accuracy rate was high. We carried out a flight measurement comparison experiment at the Wenhua Road Campus of Henan Agricultural University, and the measurement data were highly consistent with the data from the national monitoring stations. We also conducted an agri-environmental atmospheric measurement experiment in Muzhai Village and obtained the vertical distribution data of PM concentration at the nearby measuring point when the harvester was working. The results showed that after the harvester worked for a period of time, the PM2.5, PM10, and TSP concentrations reached the maximum at the altitude of 20 m at the measurement point, which were 80, 198, and 384 μg/m3, respectively, 2.64~3.10 times the particle concentration in the environment before the harvester began to work. Our new platform had high mobility, sensitive reading, and stable communication during the experiment, and had high application value in agricultural environmental monitoring.

Diese Arbeit untersucht Katalysatorheizstrategien auf die Emissionen während des Heizbetriebs, aber auch bei sich unmittelbar anschließender Lastaufschaltung bei verschiedenen Motortemperaturen. Es wird ein Brennverfahren vorgestellt, das auf die Erwärmung des Brennraums abzielt, ohne das Katalysatorheizen zu vernachlässigen. Die Untersuchungen finden an einem Ottomotor statt. Es wird auf die entstehenden Emissionen eingegangen. Außerdem wird die Flammenausbreitung experimentell bewertet.

Biomass boiler plants of small thermal power (under 35 kW thermal), in particular for domestic heating, have greatly contributed to the rise in particulate emissions. Several technologies, like fabric filters or electrostatic precipitators, can achieve high particulate removal efficiency, over 99%. However, the application of these technologies is limited by excessive prices and operational problems, since the high cost does not allow their use in small size plants. The paper shows a comparative performance analysis of different scrubber systems which have been designed, realized and tested with flue gas produced by biomass combustion in a 25 kW thermal boiler. The experimental campaigns were realized in the laboratory of the Department of Industrial Engineering of the University of Bologna. Experimental results demonstrate the achievements of particulate removal efficiency which is comparable with the efficiency of industrial technologies. Moreover, a preliminary energy balance was carried out to assess the energy cost of the different scrubber systems tested.

In the past several decades, biofuels have emerged as candidates to help mitigate the issues of global warming, fossil fuel depletion and, in some cases, atmospheric pollution. To date, the only biofuels that have achieved any significant penetration in the global transportation sector are ethanol and biodiesel. The global consumption of biodiesel was rapidly increased from 2005. The goal of this study was to examine the chemical composition on particulate pollutant emissions from a diesel engine operating on several different biodiesels. Tests were performed on non-road diesel engine. Experiments were performed on 5 different fuel blends at 2 different engine loading conditions (50% and 75%). 5 different fuel blends were ultra-low sulfur diesel (ULSD, 100%), soy biodiesel (Blend 20% and Blend 100%) and canola biodiesel (Blend 20% and Blend 100%). The chemical properties of particulate pollutants were characterized using an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS). Organic matter and nitrate were generally the most abundant aerosol components and exhibited maximum concentration of 1207 μg/m³ and 30 μg/m³, respectively. On average, the oxidized fragment families (C x H y O₁+, and C x H y O z +) account for ~13% of the three family sum, while ~87% comes from the C x H y + family. The two peaks of C₂H₃O₂ (m/z 59.01) and C₃H 7 O (m/z 59.04) located at approximately m/z 59 could be used to identify atmospheric particulate matter directly to biodiesel exhaust, as distinguished from that created by petroleum diesel in the AMS data.

International audience; The growing concern about air quality and the impact exhaust particles can have on the environment has resulted in the increased use of alternative fuels. A sampling campaign from a conventional heavy diesel engine operated in typical transient cycle or steady-state condition, and running on diesel, 30% biodiesel in diesel, and 100% biodiesel was carried out. The particulate composition was characterized using Fourier Transform Infrared (FTIR) spectroscopy, Two-step Laser Mass Spectrometry (L2MS), Secondary Ion Mass Spectrometry (SIMS), thermo-optical analysis, and capillary electrophoresis. Elemental carbon is demonstrated to decrease from diesel to 100% biodiesel, in agreement with the evolution of aromatic bands and the MS abundance of Cn– fragments, while organic carbon exhibits a constant level irrespective of the working regime. Aliphatic, aromatic, carboxyl, carbonyl, hydroxyl functionalities, and nitro compounds are found to depend on the engine-working regime. Mass spectra are mainly characterized by alkyl fragments (CnH2n+1+), associated to normal and branched alkanes, PAHs and their alkylated derivatives. The addition of biodiesel to diesel changes the particulate composition towards more oxygenated constituents, such as carbonyl groups attributed to methyl ester CH3O+ fragments of unburned biodiesel. Fuel-specific fragments have been identified, such as C3H7O+ for diesel, and C2H3O2+ and CH3O– for biodiesel. Nitrogenized compounds are revealed by -NO2 functionalities and N-containing fragments. Principal Component Analysis (PCA) was successfully applied to discriminate the engine operating conditions, with a higher variance given by the fuel, thus allowing to better evaluate the environmental impacts of alternative energy source emissions.

PPTの低推進効率の要因の1つと考えられているLate Time Vaporizationを軽減する手段として、2段放電動作を提案し、その初期実験を行った。その結果、(1)適正な2段放電動作の確認、(2)2段放電法を用いることによる、推進剤消費の増加を伴わないインパルスビットの向上、が確認された。(2)の結果は、有効排気速度の上昇を表しており、2段放電動作の有効性を示すものであると考えられる。一方、問題点として、(a)他機関のPPTと比較して推力が小さい、(b)放電間隔τの選択範囲が不十分、(c)放電チャネル内の現象が未解明、などの点も挙げられたため、現在、背圧環境の改善、回路の低インダクタンス・低抵抗化、および放電間鷹設定回路の改良などを行っている段階である。今後は、改善された実験環境の下で、放電チャネル内の現象評価、および推進機形状も含めた最適化検討を行っていく予定である。また、これまでに著者らによりその有効性が示されている固体推進薬の適用についても、今後検討していきたい。, 資料番号: AA0033392056

Particulate emissions from diesel engines have been a key issue for diesel engine developers in recent decades. Their work has succeeded in reducing the exhaust particles from the combustion of fuel, which has led to increasing interest in the contribution of particulates from lubrication oil. When discussing oil-related particulate emissions, hydrocarbon particles are customarily referred to. This thesis uses a broader definition, in which oil-related particulate emissions are modelled not only by the hydrocarbons, but also include the ash, carbons, and sulphate oil particulate emissions. The model developed in the project uses input data as oil consumption and oil ash content combined with tuning parameters, such as the oil ash transfer rate (ash emissions divided by oil consumption and oil ash content). Controlled engine tests have been performed to verify assumptions and fill knowledge gaps. The model can be applied to a variety of diesel engines, although the tuning factors might have to be reset. For example, introducing diesel particulate filters would dramatically reduce the oil ash emissions, since oil ash would accumulate in the filter. Oil consumption has played a central role in the present research. The modelling results indicate that special attention should be paid to oil consumption under running conditions with a low in-cylinder temperature, since the oil survival rate is high there. Under low-load and motoring conditions, hydrocarbons proved to be the main contributor to oil-related particulate emissions. At high engine load, oil ash emissions were the largest contributor to oil-related particulate emissions. QC 20101103

The authors present results of a monitoring campaign that was carried out in an iron-making plant, located in the proximity of an urban area; such plant was subjected to a relevant environmental requalification project. The monitoring was aimed at evaluating the impact of requalification actions tracing the evolution of some environmental indicators that were measured before and after such actions.

A new phenomenological model is introduced by applying established conceptual models for direct injection combustion to develop a mathematical description of events. The model has the capability to predict particulate mass output, as well as a particulate mass history over a single combustion event. The model was developed in a Matlab-Simulink environment to promote modularity. Results of particulate mass output from single cylinder laboratory engine, and six-cylinder vehicular engine were used to determine the validity of the predictions made. Although predicted values do not perfectly match measured values, there is certainly reasonable agreement.

Laser beam cutting of fibre-reinforced plastics leads to high emissions of smoke and dust. This may cause a health risk for machinery operators due to high inhalable dust concentrations. Also, the emissions of various gaseous compounds, i.e. benzene, represent a problem. A detailed characterization of the emissions of a variety of fibre-reinforced plastics is presented. The risk potential may be minimized by suitable disposal systems.

One of peculiarities of diesel engine is soot formation contributing particulate emission. Engine manufacturers and researchers are trying to reduce this emission to the lowest possible level. Important tool in engine development are the numerical simulations. Modeling of soot formation is still on approximate level when compared with modeling of other engine related processes and there are possibilities for further development of these models. In this paper an application of soot formation model by Fusco et al. is presented. Original model is changed by addition of convective contribution in species mass conservation equation. The convection contribution was checked on realistic 3D space domain with additional analysis of temperature and local concentrations of fuel and oxygen influence on soot formation during fuel spray combustion in direct injection diesel engine.