Design Guidelines for High Performance Industrial Furnaces - High Temperature Air Combustion: From Energy Conservation to Pollution Reduction - page 245

T ABLE 5.1 (CONTINUED)

Overall Configuration of Technical Arrangements of High Performance
Industrial Furnace Development Project

Comb ustion devices Hardware condition:

Regenerative burner Position of air and gas nozzles, air and fuel

piping
Angle of air and gas nozzles
Shape and number of air and gas nozzles
Discharge flow rate of air and gas
Position and pitch of burners, paring,

Center-gun system
outer-gun (accentric gun) system
single-axis type (rotary type)
double-axis type (fixed type)

Gun

gas-circulating face, position, shape, and
structure of partition
Escape balance
Vertical heat balance
Effective gas convection method

honeycomb
ball

regenerative type

Gas duct and smoke stack Improvement in furnace bottom φ and

CG

shielding
In-furnace pressure balance and furnace
pressure control

Duct stack type Escape type

Single stack type Zero-escape type

Software condition:

φ c value distribution

Optimum furnace type (furnace length,
width, and height)
Waste heat recovery condition, heat balance
Gas recirculation conditions, partition, type,
structure, and pairing configuration
Zone devision
Combustion control: heat pattern control,
zone control, and startup control
Furnace pressure control

and calorifi

CG

heat loss through the furnace w all, the heating efficiency of the furnace increases

with the height of the furnace.
In the case of a regenerative burner furnace that features high waste heat recovery,
sufficient heat can be recovered from the exhaust gas even if the in-furnace gas
temperature is increased, where the heating efficiency does not change significantly
with the gas layer thickness. The optimal furnace height can be small. The relation-
ship between the furnace height and unit fuel consumption was determined by heat
transfer analysis using a basic heat transfer model in the same manner as with the
examination of schedule-free heating. The heat loss was set according to the area
ratio based on the data obtained from an actual furnace. Calculations were made for
both the upper region and the lower region in the furnace.

able 5.3 shows the calculation conditions and Figure 5.1 the results of the
calculations. The furnace height is at its optimum level. The optimal height is reduced
by about 1 m for both lower and upper regions of the furnace height side in the case

T