Volatile Organic Compounds in Exhaust Gas from Diesel Engines under Various Operating Conditions

2011 ◽  
Vol 12 (1) ◽  
pp. 30-40 ◽  
Author(s):  
H Ogawa ◽  
T Li
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Diesel Engines ◽  
Operating Conditions ◽  
Exhaust Gas ◽  
Volatile Organic

scholarly journals On the effects of hydrocarbon and sulphur-containing compounds on the CCN activation of combustion particles

2005 ◽  
Vol 5 (3) ◽  
pp. 2599-2642 ◽  
Author(s):  
A. Petzold ◽  
M. Gysel ◽  
X. Vancassel ◽  
R. Hitzenberger ◽  
H. Puxbaum ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Gas Turbine ◽  
Sulphuric Acid ◽  
Organic Compounds ◽  
Operating Conditions ◽  
Water Soluble ◽  
Data Set ◽  
Combustion Particles ◽  
Volatile Organic

Abstract. The European PartEmis project (''Measurement and prediction of emissions of aerosols and gaseous precursors from gas turbine engines'') was focussed on the characterisation and quantification of exhaust emissions from a gas turbine engine. A comprehensive suite of aerosol, gas and chemi-ion measurements were conducted under different combustor operating conditions and fuel sulphur concentrations. Combustion aerosol characterisation included on-line measurements of mass and number concentration, size distribution, mixing state, thermal stability of internally mixed particles, hygroscopicity, cloud condensation nuclei (CCN) activation potential, and off-line analysis of chemical composition. Modelling of CCN activation of combustion particles was conducted using microphysical and chemical properties obtained from the measurements as input data. Based on this unique data set, the role of sulphuric acid coatings on the combustion particles, formed in the cooling exhaust plume through either direct condensation of gaseous sulphuric acid or coagulation with volatile condensation particles nucleating from gaseous sulphuric acid, and the role of the organic fraction for the CCN activation of combustion particles was investigated. It was found that particles containing a large fraction of non-volatile organic compounds grow significantly less at high relative humidity than particles with a lower content of non-volatile OC. Also the effect of the non-volatile OC fraction on the potential CCN activation is significant. While a coating of water-soluble sulphuric acid increases the potential CCN activation, or lowers the activation diameter, respectively, the non-volatile organic compounds, mainly found at lower combustion temperatures, can partially compensate this sulphuric acid-related enhancement of CCN activation of carbonaceous combustion aerosol particles.

scholarly journals Volatile organic compounds (VOCs) control by combining bio-scrubber and ozone pretreatment

2020 ◽  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Removal Efficiency ◽  
Advanced Oxidation Process ◽  
Operating Conditions ◽  
Gaseous Emissions ◽  
Model Substance ◽  
Volatile Organic ◽  
Ozone Pretreatment ◽  
Culture Growth

<p>Volatile Organic Compounds (VOCs) are toxic for the environment and human health and their tendency to readily volatilize in the atmosphere can lead to problems connected to odours annoyance. Conventional VOCs gaseous emissions treatments entail the application of chemical-physical processes, only promoting the transfer of the contaminants from gas to liquid and/or solid phases. Advanced Oxidation Process (AOPs) and biological processes, conversely, support the oxidation of the organic pollutants, promoting their conversion into harmless and odourless compounds. The integration of booth processes is suggested to increase treatability of VOC. The research presents the application of an innovative treatment system composed by an AOPs pretreatment coupled with a bio-scrubbing unit for the abatement of VOCs, with the aim to increase the removal efficiency. The evaluation of the performance of the proposed system is discussed with reference to the analysis carried out using toluene as model substance. Different operating conditions have been analyzed and investigated to optimize the removal efficiency. The results show that the ozonation applied as pretreatment to the biological process may promote an increase of the pollutant biodegradability along with synergic effects due to the absorption of the ozone derived compounds into the culture growth, resulting in a significant enhancement of removal performances respect to the conventional biotechnologies. A toluene removal efficiency up to 95% were obtained under the investigated conditions.</p>

scholarly journals Simulation of ozonolysis of volatile organic compounds: Effect on flue gas composition

2021 ◽  
Vol 1195 (1) ◽  
pp. 012012
Author(s):  
M Lim ◽  
A R Lea-Langton
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Flue Gas ◽  
Combustion Efficiency ◽  
Operating Conditions ◽  
Gas Composition ◽  
Thermal Output ◽  
Excess Air ◽  
Volatile Organic ◽  
Low Temperature Plasmas

Abstract This study shows that the reaction of ozone with various volatile organic compounds (VOC) yields different flue gas composition in terms of the carbon dioxide, oxygen and moisture contents. Steam production and thermal output requirements from a combustion system (i.e., a boiler) may dictate the range of operating conditions, such as the air to fuel mass flow rates. To improve the combustion efficiency in these operating conditions, low temperature plasmas have been used to ionize air and generate ozone as an oxidant for ozonolysis with the VOC. Therefore, this study simulates the reaction mechanism of the ozonolysis of VOC and the effect on the flue gas composition, which affects the combustion efficiency. Simulation results show that residual oxygen in the flue gas reduces, reducing the excess air. Thus, the corresponding efficiency loss through dry flue gas would be reduced. Literature data shows that emissions of alkanes, alkynes and alkenes per unit mass of solid fuel is evident for both coal and biomass, and thus ozonolysis of these VOC would reduce the excess air, improving the combustion efficiency.

scholarly journals Online measurements of the emissions of intermediate-volatility and semi-volatile organic compounds from aircraft

2013 ◽  
Vol 13 (3) ◽  
pp. 8065-8100
Author(s):  
E. S. Cross ◽  
J. F. Hunter ◽  
A. J. Carrasquillo ◽  
J. P. Franklin ◽  
S. C. Herndon ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Volatile Organic Compounds ◽  
Gas Phase ◽  
Organic Compounds ◽  
Operating Conditions ◽  
Organic Vapors ◽  
Pyrolysis Products ◽  
Volatile Organic ◽  
Online Measurements ◽  
Unburned Fuel

Abstract. A detailed understanding of the climate and air quality impacts of aviation requires detailed measurements of the emissions of intermediate-volatility and semi-volatile organic compounds (I/SVOCs) from aircraft. Currently both the amount and chemical composition of aircraft I/SVOC emissions remain poorly characterized. Here we characterize I/SVOC emissions from aircraft, using a novel instrument for the online, quantitative measurement of the mass loading and composition of low-volatility organic vapors. Emissions from the NASA DC8 aircraft were sampled on the ground, 143 m downwind of the engines and characterized as a function of engine power from ground idle (~4% maximum rated thrust) through 85% power. Results show that I/SVOC emissions are highest during engine-idle operating conditions, with decreasing but non-zero I/SVOC emissions at higher engine powers. Comparison of I/SVOC emissions with total hydrocarbon (THC) measurements, VOC measurements, and an established emissions profile indicates that I/SVOCs comprise 10–20% of the total organic gas phase emissions at idle, and an increasing fraction of the total gas phase organic emissions at higher powers. Positive matrix factorization of online mass spectra is used to identify three distinct types of I/SVOC emissions: aliphatic, aromatic and oxygenated. The volatility and chemical composition of the emissions suggest that unburned fuel is the dominant source of I/SVOCs at idle, while pyrolysis products make up an increasing fraction of the I/SVOCs at higher powers. Oxygenated I/SVOC emissions were detected at lower engine powers (≤30%) and may be linked to cracked, partially oxidized or unburned fuel components.

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