296
L. Zhang et al.
Smelting process: Limestone and crushed coal are measured by electronic belt
scale based on the proportioning ratio before transferred via the belt conveyer to the
oxygen-enriched air side blown reduction furnace, the slag with higher lead content
flows into the oxygen-enriched side blown reduction furnace, and then, is reduced
and smelted with the blown oxygen-enriched air. The heat required for the reduction
process comes from the combustion heat of the crushed coal. The lead alloy produced
by smelting is precipitated and separated from the slag in the static slag layer below
the tuyere. The slag is discharged from the slag tap into the fuming furnace, and
the lead alloy is discharged from the siphon mouth at the end of the furnace. The
carbon monoxide produced in the furnace is oxidized by the secondary air blown in
hearth the space. The high-temperature fume is cooled in waste heat boiler, purified
and dedusted by the bag filter before sent to desulfurization process. The waste heat
boiler dust and bag filter dust are returned to the smelting process.
Fuming Stage
The main reaction equations of the fuming area are as follows:
2C + O 2 = 2CO
(11)
C + ZnO = Zn (vapour) + CO
(12)
In the upper part of the fuming furnace, the tertiary air is suctioned under negative
pressure; zinc vapor and carbon monoxide are burned together.
2Zn + O 2 = 2ZnO
(13)
2CO + O 2 = 2CO 2
(14)
Smelting process: The pulverized coal is prepared in the pulverized coal preparation area from the raw coal stored in the concentrated bin. The pulverized coal
is transported via the single spiral pump with compressed air as the carrier to the
pulverized coal receiving bin of the fuming furnace workshop. The molten slag from
the reduction furnace flows into the fuming furnace and reacts with the pulverized
coal and air. The produced fume (dust) is recovered through the waste heat boiler
and dedusted by the bag filter, the collected dust is the secondary zinc oxide, and the
off-gas is emitted after desulfurization; the furnace slag is granulated before sent to
the slag dump or for sale.
L. Zhang et al.
Smelting process: Limestone and crushed coal are measured by electronic belt
scale based on the proportioning ratio before transferred via the belt conveyer to the
oxygen-enriched air side blown reduction furnace, the slag with higher lead content
flows into the oxygen-enriched side blown reduction furnace, and then, is reduced
and smelted with the blown oxygen-enriched air. The heat required for the reduction
process comes from the combustion heat of the crushed coal. The lead alloy produced
by smelting is precipitated and separated from the slag in the static slag layer below
the tuyere. The slag is discharged from the slag tap into the fuming furnace, and
the lead alloy is discharged from the siphon mouth at the end of the furnace. The
carbon monoxide produced in the furnace is oxidized by the secondary air blown in
hearth the space. The high-temperature fume is cooled in waste heat boiler, purified
and dedusted by the bag filter before sent to desulfurization process. The waste heat
boiler dust and bag filter dust are returned to the smelting process.
Fuming Stage
The main reaction equations of the fuming area are as follows:
2C + O 2 = 2CO
(11)
C + ZnO = Zn (vapour) + CO
(12)
In the upper part of the fuming furnace, the tertiary air is suctioned under negative
pressure; zinc vapor and carbon monoxide are burned together.
2Zn + O 2 = 2ZnO
(13)
2CO + O 2 = 2CO 2
(14)
Smelting process: The pulverized coal is prepared in the pulverized coal preparation area from the raw coal stored in the concentrated bin. The pulverized coal
is transported via the single spiral pump with compressed air as the carrier to the
pulverized coal receiving bin of the fuming furnace workshop. The molten slag from
the reduction furnace flows into the fuming furnace and reacts with the pulverized
coal and air. The produced fume (dust) is recovered through the waste heat boiler
and dedusted by the bag filter, the collected dust is the secondary zinc oxide, and the
off-gas is emitted after desulfurization; the furnace slag is granulated before sent to
the slag dump or for sale.