U.S. patent application number 15/021215 was filed with the patent office on 2016-08-04 for method and arrangement for treating process gas flowing from a pyrometallurgical furnace into a waste heat boiler.
This patent application is currently assigned to OUTOTEC (FINLAND) OY. The applicant listed for this patent is OUTOTEC (FINLAND) OY. Invention is credited to Tapio AHOKAINEN, Eero HUGG, Mikael JAFS, Elli MIETTINEN, Kari PIENIMAKI.
Application Number | 20160223187 15/021215 |
Document ID | / |
Family ID | 51655768 |
Filed Date | 2016-08-04 |
United States Patent
Application |
20160223187 |
Kind Code |
A1 |
PIENIMAKI; Kari ; et
al. |
August 4, 2016 |
METHOD AND ARRANGEMENT FOR TREATING PROCESS GAS FLOWING FROM A
PYROMETALLURGICAL FURNACE INTO A WASTE HEAT BOILER
Abstract
Provided are a method and an arrangement for treating process
gas flowing from a furnace space of a pyrometallurgical furnace
into a waste heat boiler that is in fluid communication with the
furnace space of the pyrometallurgical furnace at a connecting
aperture. The method comprises providing the region of the
connecting aperture between the furnace space of the
pyrometallurgical furnace and the waste heat boiler with a gas
blowing means for blowing gas into process gas flowing from the
furnace space of the pyrometallurgical furnace into the waste heat
boiler, and blowing gas with the gas blowing means into process gas
flowing from the furnace space of the pyrometallurgical furnace
into the waste heat boiler.
Inventors: |
PIENIMAKI; Kari; (Espoo,
FI) ; AHOKAINEN; Tapio; (Helsinki, FI) ; HUGG;
Eero; (Espoo, FI) ; MIETTINEN; Elli; (Espoo,
FI) ; JAFS; Mikael; (Kirkkonummi, FI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
OUTOTEC (FINLAND) OY |
Espoo |
|
FI |
|
|
Assignee: |
OUTOTEC (FINLAND) OY
Espoo
FI
|
Family ID: |
51655768 |
Appl. No.: |
15/021215 |
Filed: |
September 10, 2014 |
PCT Filed: |
September 10, 2014 |
PCT NO: |
PCT/FI2014/050688 |
371 Date: |
March 10, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F23J 15/00 20130101;
F27D 17/004 20130101; F23L 9/04 20130101; F22B 1/183 20130101; F23J
3/00 20130101; F23J 15/003 20130101 |
International
Class: |
F22B 1/18 20060101
F22B001/18; F23J 15/00 20060101 F23J015/00; F23L 9/04 20060101
F23L009/04 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 18, 2013 |
FI |
20135936 |
Claims
1-18. (canceled)
19. A method for treating process gas flowing from a furnace space
of a pyrometallurgical furnace into a waste heat boiler that is in
fluid communication with the furnace space of the pyrometallurgical
furnace at a connecting aperture, comprising a providing step for
providing the region of the connecting aperture between the furnace
space of the pyrometallurgical furnace and the waste heat boiler
with a gas blowing means for blowing gas into process gas flowing
from the furnace space of the pyrometallurgical furnace into the
waste heat boiler, a blowing step for blowing gas with the gas
blowing means into process gas flowing from the furnace space of
the pyrometallurgical furnace into the waste heat boiler, providing
the gas blowing means in a lower region of the connecting aperture
in the providing step, blowing by means of the gas blowing means
provided in the lower region of the connecting aperture gas into
the process gas from below into process gas flowing from the
furnace space of the pyrometallurgical furnace into the waste heat
boiler in the blowing step, and blowing in the blowing step gas
with the gas blowing means from below into process gas flowing from
the furnace space of the pyrometallurgical furnace into the waste
heat boiler in the connecting aperture between the furnace space of
the pyrometallurgical furnace and the waste heat boiler.
20. The method according to claim 19, further comprising using as
gas at least one of air, nitrogen-enriched air, oxygen-enriched air
and inert gas such as nitrogen or argon in the blowing step.
21. The method according to claim 19, further comprising providing
in the providing step a gas blowing means having an elongate
configuration and provided with several gas discharge openings
along the elongated configuration, and arranging the gas blowing
means to extend in the transverse direction of the flow of process
gas flowing from the furnace space of the pyrometallurgical furnace
into the waste heat boiler in the providing step.
22. The method according to claim 19, wherein the pyrometallurgical
furnace that is used in the method is any one of the following: a
suspension smelting furnace such as a flash smelting furnace or a
flash converting furnace, a top submerged lance furnace, and an
electrical furnace.
23. The method according to claim 19, wherein providing in the
providing step a gas blowing means at least partly in the
connecting aperture between the furnace space of the
pyrometallurgical furnace and the waste heat boiler.
24. The method according to claim 19, wherein blowing in the
blowing step gas with the gas blowing means into the connecting
aperture between the furnace space of the pyrometallurgical furnace
and the waste heat boiler.
25. The method according to claim 19, wherein blowing in the
blowing step gas with the gas blowing means into process gas
flowing from the furnace space of the pyrometallurgical furnace
into the waste heat boiler in the connecting aperture between the
furnace space of the pyrometallurgical furnace and the waste heat
boiler.
26. An arrangement for treating process gas flowing from a furnace
space of a pyrometallurgical furnace into a waste heat boiler that
is in fluid communication with the furnace space of the
pyrometallurgical furnace at a connecting aperture, wherein the
arrangement comprises the pyrometallurgical furnace having the
furnace space, the waste heat boiler, and the connecting aperture
between the pyrometallurgical furnace and the waste heat boiler,
and wherein the region of the connecting aperture between the
furnace space of the pyrometallurgical furnace and the waste heat
boiler is provided with a gas blowing means for blowing gas into
process gas flowing from the furnace space of the pyrometallurgical
furnace into the waste heat boiler, the gas blowing means is
provided in a lower region of the connecting aperture, the gas
blowing means provided in a lower region of the connecting aperture
is configured for blowing gas into the process gas from below into
process gas flowing from the furnace space of the pyrometallurgical
furnace into the waste heat boiler, and the gas blowing means is
configured to blow gas from below into process gas flowing from the
furnace space of the pyrometallurgical furnace into the waste heat
boiler in the connecting aperture between the furnace space of the
pyrometallurgical furnace and the waste heat boiler.
27. The arrangement according to claim 26, wherein the gas blowing
means is configured for blowing at least one of air,
nitrogen-enriched air, oxygen-enriched air and inert gas such as
nitrogen or argon.
28. The arrangement according to claim 26, wherein the gas blowing
means has an elongate configuration and being provided with several
gas discharge openings along the elongated configuration, and the
gas blowing means extends in the transverse direction of the flow
of process gas flowing from the furnace space of the
pyrometallurgical furnace into the waste heat boiler.
29. The arrangement according to claim 26, wherein the
pyrometallurgical furnace is any one of the following: a suspension
smelting furnace such as a flash smelting furnace or a flash
converting furnace, a top submerged lance furnace, and an
electrical furnace.
30. The arrangement according to claim 26, wherein the gas blowing
means is provided at least partly in the connecting aperture
between the furnace space of the pyrometallurgical furnace and the
waste heat boiler.
31. The arrangement according to claim 26, wherein the gas blowing
means is configured to blow gas into the connecting aperture
between the furnace space of the pyrometallurgical furnace and the
waste heat boiler.
32. The arrangement according to claim 26, wherein the gas blowing
means is configured to blow gas into process gas flowing from the
furnace space of the pyrometallurgical furnace into the waste heat
boiler in the connecting aperture between the furnace space of the
pyrometallurgical furnace and the waste heat boiler.
Description
FIELD OF THE INVENTION
[0001] The invention relates to a method for treating process gas
flowing from a furnace space of a pyrometallurgical furnace into a
waste heat boiler that is in fluid communication with the furnace
space of the pyrometallurgical furnace at a connecting aperture as
defined in the preamble of independent claim 1.
[0002] The invention also relates to an arrangement for treating
process gas flowing from a furnace space of a pyrometallurgical
furnace into a waste heat boiler that is in fluid communication
with the furnace space of the pyrometallurgical furnace at a
connecting aperture as defined in the preamble of independent claim
10.
[0003] By a pyrometallurgical furnace is in this context meant for
example, but not excluding other types of pyrometallurgical
furnaces, a suspension smelting furnace, a top submerged lance
furnace i.e. a TSL furnace, or an electrical furnace.
[0004] In order to recover metals, such as copper, nickel or lead,
from sulfidic raw materials containing said materials, for instance
from ores or concentrates, a suspension smelting method may be
applied, where heat amounts contained in finely divided sulfidic
raw materials are utilized. In such suspension smelting method
sulfidic raw material and oxygen-containing gas, such as air,
oxygen-enriched air or oxygen is fed into a reaction shaft of a
suspension smelting furnace. In addition, for instance flue dust
recovered and recirculated from the process gases of the suspension
smelting furnace, as well as metallurgic slag-forming agent, flux,
is additionally fed into the reaction shaft of the suspension
smelting furnace. In the reaction shaft of the suspension smelting
furnace, the solid and gaseous feed materials react with each
other, so that in the bottom part of the suspension smelting
furnace, i.e. in the settler, there are formed at least two molten
phases, a slag phase and a matte phase containing the metal to be
recovered. The molten phases that are formed in the bottom part of
the suspension smelting furnace are removed from the suspension
smelting furnace at regular intervals. Sulfur dioxide containing
process gases created in the reaction shaft of the suspension
smelting furnace are conducted, via the settler, to an uptake shall
of the suspension smelting furnace, and from the uptake shaft
further to a waste heat boiler connected to the suspension smelting
furnace, in which waste heat boiler the process gases from the
suspension smelting furnace are cooled, and at the same time the
solids, i.e. flue dust, contained in the gas are removed.
[0005] When the suspension smelting furnace process gases are
transferred from the uptake shaft of the suspension smelting
furnace to the waste heat boiler, the flowing direction of the
gases is changed from an essentially vertical direction to an
essentially horizontal direction. Moreover, because the flowing
area of the connecting aperture between the uptake shaft and the
waste heat boiler is made essentially smaller than that of the
uptake shaft in order to reduce the heat losses from the suspension
smelting furnace, contacts of sulfur dioxide bearing process gases
with the walls of the suspension smelting furnace cannot be
avoided. Further, because the temperature of the process gases is
dropped towards the top part of the uptake shaft of the suspension
smelting furnace, molten particles contained in the process gases
start to solidify, and when touching the uptake shaft walls, they
attach to the wall, particularly in the vicinity of the connecting
aperture between the uptake shaft and the waste heat boiler. Thus,
in the vicinity of the connecting aperture, there is accumulated
dust accretions or build-up that obstruct the flowing of the
process gases and must therefore be broken apart. Removal of such
build-up can be hazardous and required a shutdown.
[0006] Publication WO 02/01131 presents an apparatus for
mechanically breaking up and detaching dust accretions created by
process gases and accumulated on the inner walls of a suspension
smelting furnace and/or a waste heat boiler permanently connected
to the suspension smelting furnace. In this known solution, on the
outer surface of the wall of the suspension smelting furnace and/or
the waste heat boiler, in the vicinity of the connecting point of
the suspension smelting furnace and the waste heat boiler, there is
installed at least one striker device, whereby there can be created
a mechanical impact effect and mechanical contact between the
apparatus and at least one of the dust accretions.
[0007] Publication U.S. Pat. No. 6,228,144 presents a method for
operating waste heat boiler in flash-smelting furnace. In a copper
flash-smelting works, forced oxidation of dust is prevented,
adhesion of dust to a boiler water tube is reduced, and on-line
ratio and productivity index is improved. The temperature at the
WHB radiation section outlet is greatly reduced and the atmosphere
within the WHB radiation section is controlled by blowing the mixed
gas of nitrogen gas and air from the feed aperture established in
the wall into the boiler radiation section of the waste heat boiler
of the flash-smelting furnace in a copper flash-smelting works.
Objective of the Invention
[0008] The object of the invention is to provide a method and an
arrangement for treating process gas flowing from a furnace space
of a pyrometallurgical furnace into a waste heat boiler that is in
fluid communication with the furnace space of a pyrometallurgical
furnace at an opening with the aim to prevent or at least to
minimized the formation of build-up in the connecting aperture
between the furnace space of the pyrometallurgical furnace and the
waste heat boiler.
Short Description of the Invention
[0009] The method of the invention is characterized by the
definitions of independent claim 1.
[0010] Preferred embodiments of the method are defined in the
dependent claims 2 to 9.
[0011] The arrangement of the invention is correspondingly
characterized by the definitions of independent claim 10.
[0012] Preferred embodiments of the arrangement are defined in the
dependent claims 11 to 18.
[0013] The invention is based on providing the region of the
connecting aperture between the furnace space of the
pyrometallurgical furnace and the waste heat boiler with a gas
blowing means for blowing gas into process gas flowing from the
furnace space of the pyrometallurgical furnace into the waste heat
boiler and on blowing gas with the gas blowing means into process
gas flowing from the furnace space of the pyrometallurgical furnace
into the waste heat boiler.
[0014] The invention provides for several advantages. Especially in
suspension smelting furnaces the formation of build-up in the
connecting aperture between the uptake shaft of a suspension
smelting furnace and the waste heat boiler is prevented or at least
reduced, because the gas cools down or extinguish the burning dust
particles in the process gases quickly before they hit the surfaces
of the connecting aperture and begin to form build-up. For example
uneven burning of concentrate, feed disturbances or changes in
physical or chemical properties of the feed in a suspension
smelting process can lead to delayed burning of concentrate all the
way through the waste heat boiler.
[0015] Especially in suspension smelting furnaces the gas can also
be used for flushing the lower part of the connecting aperture
between the uptake shaft of a suspension smelting furnace and the
waste heat boiler and keep it cleaner from build-up and thereby
improve the installation of a damper for temporary closing the
connecting aperture between the uptake shaft of a suspension
smelting furnace and the waste heat boiler.
[0016] Especially in suspension smelting furnaces the flue dust in
process gas coming from the uptake shaft of the suspension smelting
furnace off-gas must be sulfatized in order to achieve good flowing
ability of the dust. The gas that is fed in the region of the
connection aperture can also be used for sulfatizing particles in
the process gas by mixing sulfatizing gas with the process gas.
With the arrangement it is possible to eliminate or to reduce the
amount of sulfation air nozzles in the waste heat boiler. Oxidic or
sulfidic dust reacts together SO.sub.3 and/or with SO.sub.2 and
oxygen from the sulfatation gas and forms metal sulfates.
LIST OF FIGURES
[0017] In the following the invention will described in more detail
by referring to the figures of which
[0018] FIG. 1 is a schematical side-view illustration of an
installation comprising a suspension smelting furnace and a waste
heat boiler that is connected to an uptake shaft of the suspension
smelting furnace at an opening between the uptake shaft of the
suspension smelting furnace and the waste heat boiler and where the
region of the opening is provided with a gas blowing means,
[0019] FIG. 2 shows a gas blowing means according to an
embodiment,
[0020] FIG. 3 is a schematical side-view illustration of an
installation comprising a top submerged lance furnace and a waste
heat boiler that is connected to the top submerged lance furnace at
an opening between the top submerged lance furnace and the waste
heat boiler and where the region of the opening is provided with a
gas blowing means, and
[0021] FIG. 4 is a schematical side-view illustration of an
installation comprising an electrical furnace and a waste heat
boiler that is connected to the electrical furnace at an opening
between the electrical furnace and the waste heat boiler and where
the region of the opening is provided with a gas blowing means.
DETAILED DESCRIPTION OF THE INVENTION
[0022] The invention relates to a method and to an arrangement for
treating process gas flowing from a furnace space of a
pyrometallurgical furnace 1 into a waste heat boiler that is in
fluid communication with the furnace space (not marked with a
reference numeral) of the pyrometallurgical furnace 1 at a
connecting aperture.
[0023] The pyrometallurgical furnace 1 that is used in the method
or in the arrangement can for example be any one of the following:
a suspension smelting furnace 1a such as a flash smelting furnace
or a flash converting furnace, a top submerged lance furnace 1b,
and an electrical furnace 1c.
[0024] FIG. 1 shows an example of an installation comprising a
pyrometallurgical furnace 1 in the form of a suspension smelting
furnace 1a and a waste heat boiler 2. The suspension smelting
furnace 1a comprises a reaction shaft 3 defining a reaction shaft
space, a lower furnace 4 defining a lower furnace space, and an
uptake shaft 5 defining an uptake shaft space. In FIG. 1 the
furnace space of the pyrometallurgical furnace 1 is formed by the
uptake shaft space of the uptake shaft 5 of the suspension smelting
furnace 1a. The uptake shaft 5 of the suspension smelting furnace
1a is in fluid connection with the waste heat boiler 2 via a
connecting aperture 6 so that process gas 8 that is produced in the
suspension smelting process in the suspension smelting furnace 1a
can flow from the uptake shaft 5 of the suspension smelting furnace
1a into the waste heat boiler 2. Because the basic function
principle of such suspension smelting furnace 1a is known in the
art for example from publication WO 2007/113375, neither the
function principle of such suspension smelting furnace 1a nor the
suspension smelting process will be described in greater detail
here.
[0025] FIG. 3 shows an example of an installation comprising a
pyrometallurgical furnace 1 in the form of a top submerged lance
furnace 1b and a waste heat boiler 2. In FIG. 5, the furnace space
of the pyrometallurgical furnace 1 is formed by the furnace space
(not marked with a reference numeral) of the top submerged lance
furnace 1b. The furnace space of the top submerged lance furnace 1b
is in fluid connection with the waste heat boiler 2 via a
connecting aperture 6 so that process gas 8 that is produced in the
smelting process in the top submerged lance furnace 1b can flow
from the furnace space of the top submerged lance furnace 1b into
the waste heat boiler 2.
[0026] FIG. 4 shows an example of an installation comprising a
pyrometallurgical furnace 1 in the form of an electrical furnace 1c
and a waste heat boiler 2. In FIG. 6 the furnace space of the
electrical furnace 1c is in fluid connection with the waste heat
boiler 2 via a connecting aperture 6 so that process gas 8 that is
produced in the smelting process in the electrical furnace 1c can
flow from the furnace space of the electrical furnace 1c into the
waste heat boiler 2.
[0027] First the method and some preferred embodiment and variants
thereof will be described in greater detail.
[0028] The method comprises a providing step for providing the
region of the connecting aperture 6, preferably the connecting
aperture 6, between the furnace space of the pyrometallurgical
furnace 1 and the waste heat boiler 2 with a gas blowing means 7
for blowing gas into process gas 8 flowing from the furnace space
of the pyrometallurgical furnace 1 into the waste heat boiler
2.
[0029] The method comprises a blowing step for blowing gas with the
gas blowing means 7 into process gas 8 flowing from the furnace
space of the pyrometallurgical furnace 1 into the waste heat boiler
2.
[0030] The method comprises preferably, but not necessarily, using
as gas in the blowing step at least one of the following: air,
nitrogen-enriched air, oxygen-enriched air and inert gas such as
nitrogen or argon.
[0031] The providing step of the method comprises preferably, but
not necessarily, providing a gas blowing means 7 in a lower region
of the connecting aperture 6, and the blowing step of the method
comprises preferably, but not necessarily, blowing gas into the
process gas 8 from below into process gas 8 flowing from the
furnace space of the pyrometallurgical furnace 1 into the waste
heat boiler 2.
[0032] The providing step of the method comprises preferably, but
not necessarily, providing a gas blowing means 7 in at least one
side region of the connecting aperture 6, and the blowing step of
the method comprises preferably, but not necessarily, blowing gas
into the process gas 8 from the side into process gas 8 flowing
from the furnace space of the pyrometallurgical furnace 1 into the
waste heat boiler 2.
[0033] The providing step of the method comprises preferably, but
not necessarily, providing a gas blowing means 7 in an upper region
of the connecting aperture 6, and the blowing step of the method
comprises preferably, but not necessarily, blowing gas into the
process gas 8 from above into process gas 8 flowing from the
furnace space of the pyrometallurgical furnace 1 into the waste
heat boiler 2.
[0034] The providing step of the method comprises preferably, but
not necessarily, providing a gas blowing means 7 having an elongate
configuration and provided with several gas discharge openings 9
along the elongated configuration, and arranging the gas blowing
means 7 to extend in the transverse direction of the flow of
process gas 8 flowing from the furnace space of the
pyrometallurgical furnace 1 into the waste heat boiler 2. The gas
blowing means 7 can for example be provided with a plurality of gas
discharge openings 9.
[0035] In case the pyrometallurgical furnace 1 in the method is a
suspension smelting furnace 1a, the method may include adjusting
the amount of gas that is blown into process gas 8 flowing from the
uptake shaft 5 of a suspension smelting furnace 1a into the waste
heat boiler 2 based on a calculated sulfatization need of the
process gas 8.
[0036] In case the pyrometallurgical furnace 1 in the method is a
suspension smelting furnace 1a, the method may include adjusting
the amount of gas that is blown into process gas 8 flowing from the
uptake shaft 5 of a suspension smelting furnace 1a into the waste
heat boiler 2 based on measured residual oxygen content in the
process gas 8.
[0037] The providing step of the method comprises preferably, but
not necessarily, providing a gas blowing means 7 at least partly in
the connecting aperture 6 between the furnace space of the
pyrometallurgical furnace 1; 1a; 1b; 1c and the waste heat boiler
2.
[0038] The blowing step of the method comprises preferably, but not
necessarily, blowing in the blowing step gas with the gas blowing
means 7 into the connecting aperture 6 between the furnace space of
the pyrometallurgical furnace 1; 1a; 1b; 1c and the waste heat
boiler 2.
[0039] The blowing step of the method comprises preferably, but not
necessarily, blowing blowing step gas with the gas blowing means 7
into process gas 8 flowing from the furnace space of the
pyrometallurgical furnace 1; 1a; 1b; 1c into the waste heat boiler
2 in the connecting aperture 6 between the furnace space of the
pyrometallurgical furnace 1; 1a; 1b; 1c and the waste heat boiler
2.
[0040] The blowing step of the method comprises preferably, but not
necessarily, blowing blowing step gas with the gas blowing means 7
from below into process gas 8 flowing from the furnace space of the
pyrometallurgical furnace 1; 1a; 1b; 1c into the waste heat boiler
2 in the connecting aperture 6 between the furnace space of the
pyrometallurgical furnace 1; 1a; 1b; 1c and the waste heat boiler
2.
[0041] Next the arrangement some preferred embodiments and variants
of the arrangement will be described in greater detail.
[0042] In the arrangement the region of the connecting aperture 6
between the furnace space of the pyrometallurgical furnace 1 and
the waste heat boiler 2 is provided with a gas blowing means 7 for
blowing gas into process gas 8 flowing from the furnace space of
the pyrometallurgical furnace 1 into the waste heat boiler 2.
[0043] The gas blowing means 7 are preferably, but not necessarily,
configured for blowing at least one of air, nitrogen-enriched air,
oxygen-enriched air and inert gas such as nitrogen or argon.
[0044] Gas blowing means 7 are preferably, but not necessarily,
provided in a lower region of the connecting aperture 6, and gas
blowing means 7 provided in the lower region of the connecting
aperture 6 are preferably, but not necessarily, configured for
blowing gas into the process gas 8 from below into process gas 8
flowing from the furnace space of the pyrometallurgical furnace 1
into the waste heat boiler 2.
[0045] Gas blowing means 7 are preferably, but not necessarily,
provided in at least one side region of the connecting aperture 6,
and gas blowing means 7 provided in a side region of the connecting
aperture 6 are preferably, but not necessarily, configured for
blowing gas into the process gas 8 from a side into process gas 8
flowing from the furnace space of the pyrometallurgical furnace 1
into the waste heat boiler 2.
[0046] Gas blowing means 7 are preferably, but not necessarily,
provided in an upper region of the connecting aperture 6, and gas
blowing means 7 provided in the upper region of the connecting
aperture 6 are preferably, but not necessarily, configured for
blowing gas into the process gas 8 from above into process gas 8
flowing from furnace space of the pyrometallurgical furnace 1 into
the waste heat boiler 2.
[0047] The gas blowing means 7 may, as shown in FIGS. 2 to 4, have
an elongate configuration and be provided with several gas
discharge openings along the elongated configuration, and the gas
blowing means 7 may extend in the transverse direction of the flow
of process gas 8 flowing from the furnace space of the
pyrometallurgical furnace 1 into the waste heat boiler 2. The gas
blowing means 7 can for example be provided with a plurality of gas
discharge openings.
[0048] In case the pyrometallurgical furnace 1 in the arrangement
is a suspension smelting furnace 1a, the arrangement may be
configured to adjust the amount of gas that is blown into process
gas 8 flowing from the furnace space of the pyrometallurgical
furnace 1 into the waste heat boiler 2 based on the calculated
sulfurization need.
[0049] In case the pyrometallurgical furnace 1 in the arrangement
is a suspension smelting furnace 1a, the arrangement may be
configured to adjust the amount of gas that is blown into process
gas 8 flowing from the furnace space of the pyrometallurgical
furnace 1 into the waste heat boiler 2 based on a measured residual
oxygen content in the process gas 8.
[0050] The gas blowing means 7 are preferably, but not necessarily,
provided at least partly in the connecting aperture 6 between the
furnace space of the pyrometallurgical furnace 1; 1a; 1b; 1c and
the waste heat boiler 2.
[0051] The gas blowing means 7 are preferably, but not necessarily,
configured to blow gas into the connecting aperture 6 between the
furnace space of the pyrometallurgical furnace 1; 1a; 1b; 1c and
the waste heat boiler 2.
[0052] The gas blowing means 7 are preferably, but not necessarily,
configured to blow gas into process gas 8 flowing from the furnace
space of the pyrometallurgical furnace 1; 1a; 1b; 1c into the waste
heat boiler 2 in the connecting aperture 6 between the furnace
space of the pyrometallurgical furnace 1; 1a; 1b; 1c and the waste
heat boiler 2.
[0053] The gas blowing means 7 are preferably, but not necessarily,
configured to blow gas from below into process gas 8 flowing from
the furnace space of the pyrometallurgical furnace 1; 1a; 1b; 1c
into the waste heat boiler 2 in the connecting aperture 6 between
the furnace space of the pyrometallurgical furnace 1; 1a; 1b; 1c
and the waste heat boiler 2.
[0054] It is apparent to a person skilled in the art that as
technology advanced, the basic idea of the invention can be
implemented in various ways. The invention and its embodiments are
therefore not restricted to the above examples, but they may vary
within the scope of the claims.
* * * * *