Abstract: A sampling system and method for sampling particulate matter from a high-temperature, high-pressure gas stream. A cyclone sampler for use at high temperatures and pressures, and having threadless sacrificial connectors is disclosed. Also disclosed is an improved cascade impactor including jet plates with integral spacers, and alignment features provided for aligning the jet plates with their associated collection substrates. An activated bauxite alkali collector is disclosed, and includes an alumina liner. The sampling system can be operated remotely or locally, and can be permanently installed or configured as a portable system.

Abstract: A method is provided for enhancing the efficiency of fly ash collection in an electrostatic precipitator by lowering the resistivity of the fly ash particles in the flue gas, comprising the steps of introducing an aqueous solution of ammonium sulfate or ammonium bisulfate into a slipstream of hot flue gas or hot combustion air in a chamber external to the main flue gas duct wherein thermal decomposition is effected, removing the NH.sub.3 decomposition product by catalytic oxidation to increase the effectiveness of the SO.sub.3 decomposition product, and then distributing the SO.sub.3 decomposition product into the main flue gas stream exiting from the air preheater at a point upstream from the electrostatic precipitator.