Design Guidelines for High Performance Industrial Furnaces - High Temperature Air Combustion: From Energy Conservation to Pollution Reduction - page 264

Combustion air

Exhaust gas 1

Thermal storage media

Steel
discharging
side

Steel
charging side

1 Non-combustion zone 2 Preheating zone 3 Heating zone 4 Soaking zone

Skids

Exhaust gas 2

FIGURE 5.27 Continuous reheating furnace for semifinished steel with regenerative heat
exchangers.

B B B B B B B

B B B B B B B

B B B B B B B

B B B B B B B

(C) Air/gas flow system

(A) Air/gas flow system

1400 1400

1200 1200

1000 1000

800 800

600 600

Upper furnace temperature
Top surface
Center
Backside surface

Upper furnace temperature
Top surface
Center
Backside surface

400 400

200 200

0 0

0 10 20 30 0 10 20 30 40

Furnace length, m Furnace length, m

(B) Distribution of temperature of steel (D) Distribution of temperature of steel

FIGURE 5.28 Distributions of temperature of steel in a conventional furnace (C, D) and a
high performance furnace (A, B) with air/gas flow systems.

For the basic functions of the simulator, it was also decided that the simulator
would be a process simulator for studying such characteristics of a reheating furnace
as fuel consumption and required furnace length. It was then necessary to obtain
the temperature of steel in the furnace and to observe the effects of varying other
parameters. For calculation method and input data, the simulator is a simplified
model and basic data are input to carry out the calculations. The furnace size, zone
length, furnace height, and furnace width serve as one factor. The simulator calcu-
lates the heat balance ( Figure 5.29 ) and the following are input as operational
conditions required for the calculation: