scholarly journals Reduction of Toxic Air Contaminants (TACs) and particulate matter emissions from heavy-duty natural gas engines

2006 ◽  
Author(s):  
Hemanth K. Kappanna
Author(s):  
Hemanth Kappanna ◽  
Marc C. Besch ◽  
Daniel K. Carder ◽  
Mridul Gautam ◽  
Adewale Oshinuga ◽  
...  

Increasing urban pollution levels have led to the imposition of evermore stringent emissions regulations on heavy-duty engines used in transit buses. This has made compressed natural gas (CNG) a promising fuel for reducing emissions, particularly particulate matter (PM) from heavy-duty transit buses. Indeed, research studies performed at West Virginia University (WVU) and elsewhere have shown that pre-2010 compliant natural gas engines emit an order of magnitude lower PM emissions, on a mass basis, when compared to diesel engines without any exhaust aftertreatment devices. However, on a number basis, particle emissions in the nanoparticulate range were an order of magnitude higher for natural gas fueled buses than their diesel counterparts. There exists a significant number of pre-2007 CNG powered buses in transit agencies in the US and elsewhere in the world. Therefore, an exhaust aftertreatment device was designed and developed by WVU, in association with Lubrizol, to retrofit urban transit buses powered by MY2000 Cummins Westport C8.3G+ heavy-duty CNG engines, and effectively reduce Toxic Air Contaminants (TAC) and PM (mass and number count) exhaust emissions. The speciation results showed that the new exhaust aftertreatment device reduced emissions of metallic elements such as iron, zinc, nonmetallic minerals such as calcium, phosphorus and sulfur derived from lube oil additives to non-detectable levels, which otherwise could contribute to an increase in number count of nanoparticles. The carbonyl compounds were reduced effectively by the oxidation catalyst to levels below what were found in the dilution air. Also, hydrocarbons identified as TAC’s by California Air Resource Board (CARB) [1] were reduced to non-detectable levels. This ultimately reduced the number of nanoparticles to levels equal to that found in the dilution air.


1994 ◽  
Author(s):  
C. J. J. Den Ouden ◽  
R. H. Clark ◽  
L. T. Cowley ◽  
R. J. Stradling ◽  
W. W. Lange ◽  
...  

Author(s):  
Matthieu Vierling ◽  
Michel Moliere ◽  
Paul Glaser ◽  
Richard Denolle ◽  
Sathya Nayani ◽  
...  

Abstract Gas turbines are often the master pieces of the utilities that power Oil and Gas (O&G) installations as they most often operate in off-grid mode and must reliably deliver the electric power and the steam streams required by all the Exploration/Production (EP) or refining processes. In addition to reliability, fuel flexibility is an important score card of gas turbines since they must permanently accommodate the type of fuel which is available on the particular O&G site. For instance, during the operation of an associated gas field, crude oil comes out from the well heads as the gas reserves are declining or depleted. The utility gas turbine must then be capable to successively burn natural gas and crude oil and often to co-fire both fuels. An important feature of crude oils is that their combustion tends to emit significantly more particulate matter (PM) than do distillate oil and natural gas as they contain some heavier hydrocarbon ends. Taking account of the fact that some alternative liquid fuels emit more particulates matter (PM) than distillate oils, GE has investigated a class of soot suppressant additives that have been previously tested on light distillate oil (No 2 DO). As a continuation of this development, these products have been field-tested at an important refining site where several Frame 6B gas turbines have been converted from natural gas to crude oil with some units running in cofiring mode. This field test showed that proper injections of these fuel additives, at quite moderate concentration levels, enable a substantial abatement of the PM emissions and reduction of flue gas opacity. This paper outlines the main outcomes of this field campaign and consolidates the overall results obtained with this smoke suppression technology.


1996 ◽  
Author(s):  
P. Corbo ◽  
M. Gambino ◽  
S. Iannaccone

Sign in / Sign up

Export Citation Format

Share Document