Patent ID: 8882884

Claim:
In an furnace exhaust system for removing an exhaust from a furnace, the exhaust comprising particulate, the furnace exhaust system comprising a particulate removal system for removing a first amount of the particulate from the exhaust, such that a second amount of the particulate exits the particulate removal system through a duct, the exhaust system further comprising a PAC injection system for injecting PAC into the exhaust downstream of the particulate removal system, a method controlling a PAC-to-particulate ratio in a portion of the exhaust system downstream of the particulate removal system comprising: measuring the second amount of the particulate remaining in the exhaust; and controlling the first amount of the particulate removed by the particulate removal system based in part on the measured second amount of particulate, wherein the step of controlling the first amount of the particulate provides a ratio of PAC-to-particulate in the portion of the exhaust system of about one part PAC to one or more parts particulate.