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.
Characterization of the composition and toxicity of particulate matter emissions from advanced heavy-duty natural gas engines
