Dry scrubber system with air preheater protection

摘要

An air quality control system (AQCS) useful for treating flue gas, such as flue gas produced by a fossil fuel fired boiler, is described. In addition to flue gas treatment, the AQCS provides for air preheater flue gas outlet flue gas temperature reduction and air preheater corrosion prevention while reducing capital costs, increasing reliability and increasing operating flexibility with regard to fuel selection.

主权项

1. An air quality control system for treating flue gas produced in a combustion process to produce cleaned flue gas comprising:
a combustion boiler equipped with an air preheater arranged for flue gas flow from the boiler through a duct and into the air preheater; ductwork for flue gas of a reduced temperature flow from the air preheater to a dry flue gas desulfurization reactor equipped with a distribution device; a sorbent supply operable to supply a sorbent to the distribution device of the dry flue gas desulfurization reactor; a water supply operable to supply water to the distribution device for mixing with the sorbent therein to produce a moistened sorbent for distribution in the dry flue gas desulfurization reactor; a particulate removal device operable to remove dried sorbent from flue gas following contact of the flue gas in the dry flue gas desulfurization reactor to produce cleaned flue gas; and a duct for transport of dried sorbent from the particulate removal device or optionally transport of moistened sorbent from the distribution device for injection of the sorbent into the duct arranged between the boiler and the air preheater for reaction with flue gas SO3 and acid gases.