Results of Investigations on the Current State of Japanese Industrial Furnaces - High Temperature Air Combustion: From Energy Conservation to Pollution Reduction - page 369

TABLE A.6
Comparison of Main Statistics on the Number of Industrial Furnaces

Fiscal Year

(a) 1992 (b) 1975 (c) 1995 (c) - (b)

Data source Facilities

emitting soot
as notified
under the law
of preventing
atmosphere
pollution

Investigation by
Agency of Natural
Resources and
Energy

Assumed values based
on this questionnaire
inquiry

Amount increased
during the two
decades (from
1975-95)

Name of facilities
Heating furnace 2,475 4,046 1571

Heat treatment
furnace

8,503 8,078 5,603 15,757 11,611 7,679 6,008

Drying furnace 7,606 5,845 4,590 -1,255

Metals melting
furnace

4,623 4,772 4,326 -446

Ceramics baking
furnace

3,755 5,215 6,512 1,297

Petroleum
heating furnace

1,619 1,764 2,526 762

Others 3,891 7,561 5,542 -2,507

Total of industrial
furnaces

29,997 33,235 39,253 5,979

10% of the electrical furnaces under 200 kVA are included in this inves-
tigation because the capacities of the electrical furnaces in this investiga-
tion are confined to those over 50 kVA. Therefore, the values obtained
during this investigation are similar to results published by the Agency of
Natural Resources and Energy in 1975.
4. The comparison between data (b) and (c), shown in Table A.6 , reveals
that a large number of heating furnaces and heat treatment furnaces have
been manufactured and introduced over the past 20 years. This is also
confirmed by the return of questionnaires from the furnace manufacturers
conducted in this investigation.

The number of industrial furnaces in Japan estimated from the questionnaires
is about 39,300 when the minimum furnace capacities are limited to those over 50
l/h of crude oil equivalent or 50 kVA (or 35,300 when the minimum furnace
capacities are limited to 200 kVA).