Convection section ash monitoring

摘要

Fouling of the convection section of a steam generator by ash or other solid deposit from the product gas stream is monitored using radiation pyrometers which determine the temperature drop across a bank of heat exchanger tubes and calculation therefrom of a fouling factor related to the degree of fouling. Soot blowers are actuated, in manual response or automatic response, to the fouling factor, to effect cleaning of the heat exchanger tubes. Heat flux meters also may be provided to determine variations in the degree of fouling transverse to the flow of the gas stream and the determinations may be used to actuate selective cleaning of parts of the tube bank.