All-mode Automatic Temperature Control System for Superheated Industrial Steam Boiler during Buffer Consumption of Gaseous Production Waste

Abstract

The matter of the efficiency increase for an industrial steam boiler during the blast furnace gas buffer consumption is considered.. When transferring to the mode with the bigger part of the blast furnace gas (in relation to the natural gas) the superheated steam temperature significantly increases because of high blast furnace gas flows and flame movement. The ordinary range of injection change is not enough for the steam temperature stabilization behind the convective superheater second stage CSS2. There is a well-known solution of this problem for drum steam boiler E220-100 (220 t/h, 10 MPa, 540°C), for the solution a combined system is used, which, in addition to the traditional regulator of the steam temperature behind the CSS2 acting upon the injection, has a steam temperature regulator behind the CSS1 acting upon the flame position by means of turning burner air-control registers. Although the system performance was considered only for one steam flow load (100%). This paper shows dependencies for parameters of the dynamical model of the superheated steam temperature regulating channel on the load in the range of 64-100%. In order to provide the all-mode performance of the system it is offered to make automatic adjustment of the regulators parameters as the function of the steam flow according to the dependencies where the process dynamic changes are taken into consideration.