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A 500 hours endurance test was performed with a heavy-duty engine (Euro IV); MAN type D 0836 LFL 51 equipped with a PM-Kat®. As fuel 100% biodiesel was used that met the European specification EN 14214. The 500 hours endurance test included both the European stationary and transient cycle (ESC and ETC) as well as longer stationary phases. During the test, regulated emissions (carbon monoxide, nitrogen oxides, hydrocarbons and particulate matter), the particle number distribution and the aldehydes emission were continuously measured. For comparison, tests with fossil diesel fuel were performed before and after the endurance test. During the endurance test, the engine was failure-free for 500 hours with the biogenic fuel. There were almost no differences in specific fuel consumption during the test, but the average exhaust gas temperature increased by about 15°C over the time. Emissions changed only slightly during the test.

Trends towards lower vehicle fuel consumption and smaller environmental impact will increase the share of Diesel hybrids and Diesel Range Extended Vehicles (REV). Because of the Diesel engine presence and the ever tightening soot particle emissions, these vehicles will still require soot particle emissions control systems. Ceramic wall-flow monoliths are currently the key players in the Diesel Particulate Filter (DPF) market, offering certain advantages compared to other DPF technologies such as the metal based DPFs. The latter had, in the past, issues with respect to filtration efficiency, available filtration area and, sometimes, their manufacturing cost, the latter factor making them less attractive for most of the conventional Diesel engine powered vehicles. Nevertheless, metal substrate DPFs may find a better position in vehicles like Diesel hybrids and REVs in which high instant power consumption is readily offered enabling electrical filter regeneration.

For the removal of NOx from the oxygen-rich diesel exhaust in mobile applications the selective catalytic reduction (SCR) is one of the most favored technologies. Well established NH₃-SCR technique uses either V₂O₅/WO₃-TiO₂ or Zeolite-based catalysts, NOx being continuously reduced by NH₃ resulting in the selective formation of nitrogen and water. A major drawback of V₂O₅-based formulations is their lower thermal stability and low temperature activity, in addition, V₂O₅ release poses serious environmental and toxicity problems. In active filter regeneration performed by post-injection of fuel the temperature may increase up to 800°C resulting in drastic loss of activity (due to poor stability of V₂O₅-based formulations) as well as discharge of V₂O₅.

Diesel particle filters (DPF) have become a standard aftertreatment component for all current and future on-road diesel engines used in the US. In Europe the introduction of EUVI is expected to also result in the broad implementation of DPF's. The anticipated general trend in engine technology towards higher engine-out NOx/PM ratios results in a somewhat changing set of boundary conditions for the DPF predominantly enabling passive regeneration of the DPF. This enables the design of a novel filter concept optimized for low pressure drop, low thermal mass for optimized regeneration and fast heat-up of a downstream SCR system, therefore reducing CO₂ implications for the DPF operation. In this paper we will discuss results from a next-generation cordierite DPF designed to address these future needs.

The use of Selective Catalytic Reduction (SCR) is becoming increasingly more popular as a way of reducing NOx emissions from heavy duty vehicles while maintaining competitive operating costs. In order to make efficient use of these systems, it's important to have a complete system approach when it comes to calibration of the engine and aftertreatment system. This paper presents a simplified model of a heavy duty SCR catalyst, primarily intended for use in combination with an engine-out emissions model to perform model based offline optimization of the complete system. The traditional way of modelling catalysts using a dense discretization of the catalyst channels and non-linear differential equation solvers to solve the heat and mass balance equations, requires too much computational power in this application. The presented model is also useful in other applications such as model based control.

Many studies show that under diesel engine operating conditions, SCR reductant sprays will impinge on the wall of exhaust pipes. In order to understand this impinging process of SCR reductant spray, and to analyze what factors affect it, a test bench was set up by means of high speed video camera. At atmospheric pressure, SCR spray was injected on a heated metal wall, the impacts of wall temperature, injection pressure, injection height and angle on developing characteristics of SCR reductant spray after impinging on the heated wall have been researched and analyzed. The results show that the heated wall temperature has a great impact on the spray developing process, when wall temperature is lower than 405K, after water evaporated the crystallized urea will remain on the wall to block exhaust pipes. When wall temperature is higher, the atomization and evaporation of SCR reductant spray will be better, and the hydrolysis process of urea will be faster.

The Acceptability of boiloff hydrogen to an Inert Gas Circulating Hydrogen Diesel System, providing a high thermal efficiency, zero nitrogen oxides and carbon dioxide emissions, is discussed. To simulate a reciprocating engine cycle, a rapid compression-expansion machine is used. The machine brings fundamental data, such as hydrogen jet penetration injected in high pressure chamber and combustion characteristics. The results show an acceptable amount of hydrogen premixed to intake mixture without major negative effects. They suggest that most of boiloff hydrogen, inevitable in the facility where liquid hydrogen is used, could be supplied to the intake mixture as part of the fuel of the hydrogen diesel engine, saving a pumping loss to compress it up to an injection pressure.

The reduction of NOx using NH₃ has been successfully practiced for stationary sources and more recently, for passenger cars and heavy-duty applications in the US and Europe. Due to the up-coming Euro 6 regulations (2014) for passenger cars and light-duty trucks, NH₃-SCR catalyst technologies are extensively studied by OEMs, catalysts manufacturers and raw materials suppliers, all looking for technologies very efficient at low temperatures, thermally stable up to 800°C and with a limited impact of the NO₂/NOx ratio on activity. Among the new emerging SCR catalytic systems, non-zeolitic zirconia-based mixed oxides were introduced recently in SAE 2008 as promising new SCR catalysts. This paper reports the progress made on these materials. "Synthetic Gas Bench Tests" performed on powder catalysts show a significant increase of the NOx conversion, in comparison with that previously reported.

Generally, an Urea-SCR system for diesel engines sets the NOx reduction efficiency to 80-90%. The SCR system is theoretically able to achieve the NOx reduction over 95%, but, due to the combination of design factors, the result is varying. The influence factors are the exhaust gas temperature, SCR control strategy, urea dosing parts, flow uniformity, etc. Some factors depend on the exhaust system package. Thus, a system engineer must consider the relation between variable requirements and variable design factors. The design targets for aftertreatment package in this work are following: Improvement of NOx reduction efficiency Improvement of noise reduction performance To meet Exhaust back-pressure requirement Minimization of package volume Minimization of urea-deposit The aftertreament strategy of the discussed subject are the SCR system for EURO V and the DPF+SCR system for Japan 2009, the developed vehicle are the heavy duty truck and the express bus.

Pollution emissions due to jet aircraft operations at the major commercial airports in the New York Metropolitan Area were estimated. The impact on air pollution of the region was assessed. Pollutants considered in this report were: carbon monoxide, nitrogen oxides, hydrocarbons, aldehydes, and particulates.

Calculations have been made of total pollution emissions at Heathrow Airport, London, from aircraft operations, heating installations, and road traffic. Comparisons were made of concentrations of pollution levels from the airport and from nearby residential areas. Measurements of smoke, sulfur dioxide, oxides of nitrogen, carbon monoxide, total hydrocarbons, and deposited matter were also carried out in different parts of the airport. Results showed that the airport was not contributing unduly to local pollution. At no time did pollution concentrations at the airport even exceed values which have been found in Central London; the highest values obtained came from road traffic in the central area.

Environmental concerns have driven the scientific community in a continuous effort to set standards for emission and noise control in a diversity of industries worldwide. The aviation industry, which currently relies on fossil fuels, is strongly driven by a growing environmental awareness, which makes it one of those that are spending huge efforts to reduce its environmental footprint. Airplanes emit several types of pollutants, mainly Carbon Monoxide (CO), Unburned Hydrocarbon (UHC), Particulate Matter (PM), Nitrogen Oxides (NOx) and Sulfur Oxides (SOx), as well as Greenhouse Gases (GHG) and noise. These emissions, which can impact both the airport surroundings, as well as the high atmosphere layers, might affect the environment, through the modification of atmosphere’s chemical and physical properties, which ultimately might cause global, regional and local effects, as well as noise annoyance to the population near the airports.

For diesel emission control technologies, reduction efficiencies of Particulate Matter (PM) control systems have been traditionally reported based on mass-based criteria. However, particle number-based criteria are now receiving increased attention. In this paper, results of real-time particle size distribution and number based evaluation of the effectiveness of multiple PM control technologies are reported on an HDD engine. An Engine Exhaust Particle Sizer (EEPS) was used for comparative analysis. The technologies that were evaluated included diesel oxidation catalysts (DOC), a DOC with an uncatalyzed wall-flow filter as a continuously regenerating diesel particulate filter (CR-DPF) system, a DOC with a catalytically coated wall-flow filter as a catalyzed CR-DPF (CCR-DPF), and a DOC with a partial filter as a continuously regenerating partial filter (CR-PF).

Recently, phenomena as Greenhouse Effects, Global Warming and Environmental Changes are being discussed more and more around the World, forcing the humanity to think and provide means capable to preserve the human life and the animal and vegetal biodiversity. Gases emissions have different sources and the contribution of each economical sector on the total amount of pollutants emitted to the atmosphere varies according to each country and time frame. In industrialized countries, transportation represents around 33% of total CO2 emissions being 12% due to air transportation (4% of total). Although relatively small, this contribution may increase significantly in the near future, if the estimative for air transportation growth is confirmed (3.5% increase per year, between 2000 and 2030).

The TRW Low NOx Burner was conceived and developed utilizing the substantial technical expertise acquired during development and production of combustion systems for rocket engines and auxiliary power units. The Low NOx Burner is based upon hydraulic and injection principles derived from the design of the Lunar Excursion Module lander rocket engine. This engine required high combustion intensities, turndown ratios and manned flight reliability. Using these basic principles, TRW has patented, developed and commercialized power burners which have demonstrated reduced pollutant levels and high thermal efficiencies. Gas, light and heavy oil burners firing over a 2 to 55 MBtu/hr have been developed and field tested. The TRW activity has also been expanded into demonstration programs to demonstrate similar performances and low emission levels in utility type boilers.

Methods for sampling, handling and measuring emissions of particulates, hydrocarbons, carbon monoxide, carbon dioxide, oxides of nitrogen and oxygenated compounds in the exhaust of aircraft turbine engines were evaluated in a cooperative experimental program conducted by industry and government at the Naval Air Propulsion Test Center in September, 1969. Non-dispersive infrared (NDIR) instruments and a Fisher chromatographic partitioner were both well suited for measuring CO and CO2. Some additional development is needed in NDIR instruments and the phenol disulphonic acid (PDS) method for measuring NOx and in the 3-methyl-2-benzothiazolinone hydrazine hydrochloride (MBTH) method for measuring oxygenated compounds.

Mercedes-Benz BlueTEC passenger cars have been on the cutting edge of clean diesel technology since 2006. These BlueTEC vehicles furthermore passed millions of kilometers in the hands of customers. SCR-equipped passenger cars already meet the most stringent exhaust emissions standards in international markets such as the USA, Europe and Japan. Diesel engines with BlueTEC technology also reduce CO₂ emissions and provide the high torque and performance associated with the diesel engine in addition to keeping exhaust emissions at the lowest possible level. Nowadays the requirements for SCR emission concepts are increasing continuously. In fact the emission legislation is getting stricter with the LEVIII emission standards in 2015. Additionally the requirements and effort for on-board diagnosis are increasing year after year. In combination with ambitious CO₂ targets all these issues constitute the further challenges of BlueTEC SCR emission concepts for worldwide markets.

Exhaust gas recirculation (EGR) cooler fouling has become a significant issue for compliance with nitrogen oxides (NOx) emissions standards. In order to better understand fouling mechanisms, eleven field-aged EGR coolers provided by seven different engine manufacturers were characterized using a suite of techniques. Microstructures were characterized using scanning electron microscopy (SEM) and optical microscopy following mounting the samples in epoxy and polishing. Optical microscopy was able to discern the location of hydrocarbons in the polished cross-sections. Chemical compositions were measured using thermal gravimetric analysis (TGA), differential thermal analysis (DTA), gas chromatography-mass spectrometry (GC-MS), x-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD). Mass per unit area along the length of the coolers was also measured.

The diesel engine is the core in the field of engineering machine power plants. While both at home and abroad for the cold start of diesel engine, the transient emission characteristics below 0 °C and above 2000m is almost a blank. Therefore, aimed at high altitude and low-temperature environment emission characteristics of cold start, this article has carried on the systematic analysis and research. In this paper, a simulation test system for the cold start of the diesel engine at low temperature at high altitude is established. The cold start experiments of a heavy diesel engine at different ambient temperatures (10°C, 0°C, -10°C and -20°C) and different altitudes (0m, 3000m, and 4000m) is carried out. In this paper, the gas emission of the diesel engine during the speed-up period of cold start is studied.

Stringent emissions standards (Euro 6 and Tier2Bin5) lead to the use of nitrogen oxides (NOx) aftertreatment. One of the most widespread technical solutions able to meet these legislations is Urea Selective Catalytic Reduction (Urea SCR). A urea aqueous solution is introduced into the exhaust system in order to reduce NOx over SCR catalyst. Before reaching the catalyst, the aqueous solution has to be transformed into ammonia. Current serial applications need long distances (≻ 400 mm) from injection point to SCR catalyst and a mixer apparatus to ensure sufficient mixing between exhaust gas and ammonia. Because of this distance, SCR catalyst is located far from the engine. The light-off of the catalyst is penalized and therefore the efficiency of the SCR system is low. The purpose of this paper is to show a compact mixing device able to ensure mixing in a short distance (~ 75 mm).