A Catalyst Surface Control Automation System for Emission Reduction During Cold Start

Author(s):  
Anastasios N. Karkanis ◽  
Pantelis N. Botsaris ◽  
Panagiotis D. Sparis

This paper presents and discusses experimental data obtained during test simulating the test cycle ECE-15 for a relatively simple method for the reduction of pollutant emissions during a cold start. During a cold start the volume of the exhaust gases is considerably smaller than the ones under full load. Therefore, only a small portion of the catalyst active surface is used to process the gases at the cold start phase. After the light-off at the initial surface the exhaust gases pass from the total catalytic surface which is already pre-heated from the first phase. The experimental results presented here indicate that there is a reduction of the pollutant emissions during the cold start of an engine. The developed system uses the 20% of the catalyst active surface during start-up and the rest of the catalyst surface after this phase, controlled by a proper automation system. At the cold start phase the system focusing the gas flow towards the center core of the monolith, so there is a quicker warm-up of the catalyst and a faster initiation of catalysis in this area. So when the remaining ceramic body of the catalytic converter is used, it is already warmed and the catalysis starts almost immediately.

2012 ◽  
Vol 13 (5) ◽  
pp. 497-513 ◽  
Author(s):  
Martin Weilenmann ◽  
Dimitrios N Tsinoglou

Various models for simulating catalytic converters are given in the literature. They deal with a wide range of different aspects. In addition to the type of catalytic converter (three-way catalytic converter, diesel oxidation catalytic converter, etc.), the aspect of complexity versus accuracy and speed can be tackled using different approaches. Moreover, the desired use has an influence on the model structure: optimization of catalyst design or prediction of emissions from real-world traffic situations or optimization of air–fuel ratio control? The model described here has been developed to predict emissions in arbitrary real-world driving patterns, both for hot driving as well as for cold-start situations. As these tests mainly last over 30 minutes (real time), the calculation effort should be small. The model should be easy to parameterize, as it should be applicable to vehicles from traffic. A model with a reduced set of chemical reactions has been developed with a particular focus on the thermal balance for cold-start cycles. Its outputs are the pollutant emissions at the tailpipe if the emissions, exhaust mass flow and temperature from the engine are given. It is applied to three-way catalytic converters. It models the chemical phenomena almost entirely based on oxygen storage and release reactions, which dominate highly transient situations. The model has been validated against a large database of measured driving cycles, carried out using different types of cars. It presents an acceptable degree of correlation between simulated and experimental results.


Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1862
Author(s):  
Tammo Zobel ◽  
Christian Schürch ◽  
Konstantinos Boulouchos ◽  
Christopher Onder

Decentralized power generation by combined heat and power plants becomes increasingly popular as a measure to advance the energy transition. In this context, a substantial advantage of small combined heat and power plants is based on the relatively low pollutant emissions. However, a large proportion of the pollutant emissions is produced during a cold-start. This fact is not reflected in governmental and institutional emission guidelines, as these strongly focus on the emission levels under steady-state conditions. This study analyzes the spark advance, the reference air/fuel ratio and an electrically heated catalyst in terms of their potential to reduce the cold-start emissions of a micro combined heat and power plant which uses a natural gas fueled reciprocating internal combustion engine as prime mover and a three-way catalytic converter as aftertreatment system. Based on these measures, control approaches were developed that account for the specific operating conditions of the class of small combined heat and power plants, e.g., full-load operation and flexible, demand-driven runtimes. The experimental data demonstrates that even solutions with marginal adaptation/integration effort can reduce cold-start emissions to a great extent.


Author(s):  
M. Assad ◽  
V. V. Grushevski ◽  
O. G. Penyazkov ◽  
I. N. Tarasenko

The concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in the gasoline combustion products emitted into the atmosphere by internal combustion engines (ICE) has been measured using the gas chromatography method. The concentrations of PAHs in the exhaust gases sampled behind a catalytic converter has been determined when the ICE operates in five modes: idle mode, high speed mode, load mode, ICE cold start mode (engine warm-up) and transient mode. Using 92 RON, 95 RON and 98 RON gasoline the effect of the octane number of gasoline on the PAHs content in the exhaust gases has been revealed. The concentration of the most carcinogenic component (benzo(α)pyrene) in the exhaust gases behind a catalytic converter significantly exceeds a reference value of benzo(α)pyrene in the atmospheric air established by the WHO and the EU for ICE in the load mode.


2021 ◽  
Vol 11 (13) ◽  
pp. 6123
Author(s):  
Katarzyna Bebkiewicz ◽  
Zdzisław Chłopek ◽  
Hubert Sar ◽  
Krystian Szczepański ◽  
Magdalena Zimakowska-Laskowska

The aim of this study is to investigate the environmental hazards posed by solid particles resulting from road transport. To achieve this, a methodology used to inventory pollutant emissions was used in accordance with the recommendations of the EMEP/EEA (European Monitoring and Evaluation Programme/European Economic Area). This paper classifies particulates derived from road transport with reference to their properties and sources of origin. The legal status of environmental protection against particulate matter is presented. The emissions of particulate matter with different properties from different road transport sources is examined based on the results of Poland’s inventory of pollutant emissions in the year 2018. This study was performed using areas with characteristic traffic conditions: inside and outside cities, as well as on highways and expressways. The effects of vehicles were classified according to Euro emissions standards into the categories relating to the emissions of different particulate matter types. The results obtained showed that technological progress in the automobile sector has largely contributed to a reduction in particulate matter emissions associated with engine exhaust gases, and that this has had slight effect on particulate matter emissions associated with the tribological processes of vehicles. The conclusion formed is that it is advisable to undertake work towards the control and reduction of road transport particulate matter emissions associated with the sources other than engine exhaust gases.


2021 ◽  
pp. 146808742110395
Author(s):  
José Galindo ◽  
Vicente Dolz ◽  
Javier Monsalve-Serrano ◽  
Miguel Angel Bernal Maldonado ◽  
Laurent Odillard

The aftertreatment systems used in internal combustion engines need high temperatures for reaching its maximum efficiency. By this reason, during the engine cold start period or engine restart operation, excessive pollutant emissions levels are emitted to the atmosphere. This paper evaluates the impact of using a new cylinder deactivation strategy on a Euro 6 turbocharged diesel engine running under cold conditions (−7°C) with the aim of improving the engine warm-up process. This strategy is evaluated in two parts. First, an experimental study is performed at 20°C to analyze the effect of the cylinder deactivation strategy at steady-state and during an engine cold start at 1500 rpm and constant load. In particular, the pumping losses, pollutant emissions levels and engine thermal efficiency are analyzed. In the second part, the engine behavior is analyzed at steady-state and transient conditions under very low ambient temperatures (−7°C). In these conditions, the results show an increase of the exhaust temperatures of around 100°C, which allows to reduce the diesel oxidation catalyst light-off by 250 s besides of reducing the engine warm-up process in approximately 120 s. This allows to reduce the CO and HC emissions by 70% and 50%, respectively, at the end of the test.


Author(s):  
Vít Marek ◽  
Lukáš Tunka ◽  
Adam Polcar ◽  
Dušan Slimařík

This paper deals with reduction of NOx-emission of a diesel engine with multiple injection pump by SCR catalytic converter. Main aim of the measurement was the detection of SCR catalyst converter efficiency. Tests were realized at the Research and Development workplace of Zetor Tractor a.s. Used engine was equipped with a multiple injection pump with electromagnetic regulator of a fuel charge. During the experiment selective catalytic reduction and diesel particulate filter were used as an after treatment of harmful pollutants reduction. Testing cycle of the eight-point test was chosen and Non-Road Steady Cycle (NRSC) was maintained according to 97/68/EC directive. Results confirmed the dependencies between temperatures of SCR catalyst and exhaust gases and the volume of exhaust gases on efficiency of SCR catalyst. During the operation load of the engine, selective catalytic reduction reached efficiency over 90 %. Used after treatment system is suitable for reduction of harmful pollutants according to the Tier 4f norm.


2021 ◽  
pp. 1-11
Author(s):  
Dominik Appel ◽  
Fabian P. Hagen ◽  
Uwe Wagner ◽  
Thomas Koch ◽  
Henning Bockhorn ◽  
...  

Abstract To comply with future emission regulations for internal combustion engines, system-related cold-start conditions in short-distance traffic constitute a particular challenge. Under these conditions, pollutant emissions are seriously increased due to internal engine effects and unfavorable operating conditions of the exhaust aftertreatment systems. As a secondary effect, the composition of the exhaust gases has a considerable influence on the deposition of aerosols via different deposition mechanisms and on fouling processes of exhaust gas-carrying components. Also, the performance of exhaust gas aftertreatment systems may be affected disadvantageously. In this study, the exhaust gas and deposit composition of a turbocharged three-cylinder gasoline engine is examined in-situ upstream of the catalytic converter at ambient and engine starting temperatures of -22 °C to 23 °C using a Fourier-transform infrared spectrometer and a particle spectrometer. For the cold start investigation, a modern gasoline engine with series engine periphery is used. In particular, the investigation of the behavior of deposits in the exhaust system of gasoline engines during cold start under dynamic driving conditions represents an extraordinary challenge due to an average lower soot concentration in the exhaust gas compared to diesel engines and so far, has not been examined in this form. A novel sampling method allows ex-situ analysis of formed deposits during a single driving cycle. Both, particle number concentration and the deposition rate are higher in the testing procedure of Real Driving Emissions (RDE) than in the inner-city part of the Worldwide harmonized Light vehicles Test Cycle (WLTC). In addition, reduced ambient temperatures increase the amount of deposits, which consist predominantly of soot and to a minor fraction of volatile compounds. Although the primary particle size distributions of the deposited soot particles do not change when boundary conditions change, the degree of graphitization within the particles increases with increasing exhaust gas temperature.


2019 ◽  
pp. 146808741985314
Author(s):  
Marcelo Real ◽  
Raffael Hedinger ◽  
Benjamín Pla ◽  
Christopher Onder

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