Abstract

The alkali content of coal has a detrimental effect on the performance of clean coal technologies, such as coal gasification and coal-fired turbines, where it causes fouling of gasifier beds and turbine blades. It is thus necessary to develop methods for alkali control in such combustion systems and have techniques available which are capable of accurately measuring gas-phase alkali concentrations. In particular, the concentrations of the major gas-phase species, NaCI and NaOH, will need to be accurately determined. In this work the concentrations of NaCI and NaOH in coal-derived gases are determined using 193 nm laser photolysis and monitoring of the subsequent atomic Na photofragment fluorescence. The technique is then applied to studies of the removal of alkali species from coal-derived gases using sorbent beds.

© 1996 Optical Society of America