Arrangement for evening out powdery solid matter feed of a concentrate burner of a suspension smelting or suspension converting furnace

A concentrate burner of a suspension smelting or suspension converting furnace includes a reaction gas feed, a powdery solid matter feed and a concentrate distributor. An arrangement for feeding powdery solid matter to the concentrate burner includes a first powdery solid matter discharge pipe for feeding powdery solid matter into the powdery solid matter feed of the concentrate burner. The first powdery solid matter discharge pipe is provided with a first partition, which divides solid matter, for dividing the first powdery solid matter discharge pipe into two essentially similar discharge pipe parts. The powdery solid matter feed of the concentrate burner comprise an annular concentrate discharge channel that surrounds the concentrate distributor of the concentrate burner. Each discharge pipe part of the first powdery solid matter discharge pipe is at least partly divided into two discharge pipe portions by a second partition.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a national stage application filed under 35 USC 371 based on International Application No. PCT/FI2010/051008 filed Dec. 10, 2010, and claims priority under 35 USC 119 of Finnish Patent Application No. FI 20096313 filed Dec. 11, 2009.

Not Applicable.

THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT

Not Applicable.

Not Applicable.

Not Applicable.

BACKGROUND OF THE INVENTION

The object of the invention is an arrangement for feeding powdery solid matter into the concentrate burner of a suspension smelting or suspension converting furnace.

FIELD OF THE INVENTION

The invention relates to the feeding equipment of powdery solid matter of a concentrate burner of a suspension smelting furnace, such as a flash smelting furnace, by means of which the feed of powdery solid matter that is fed into the reaction shaft of the suspension smelting or suspension converting furnace can be evenly distributed already to the concentrate burner.

The feed of powdery solid matter, such as concentrate, slag forming agents and flue dust into the suspension smelting or suspension converting furnace is carried out through the concentrate burner that is placed on top of the reaction shaft of the suspension smelting or suspension converting furnace. Later on in the text, the term concentrate is used exclusively, referring to all of the powdery solid matter that is fed through the concentrate burner of the suspension smelting or suspension converting furnace. It is extremely important for the proper operation of the concentrate burner that the concentrate and process gases are evenly mixed, when discharging from the concentrate burner into the reaction space, i.e., the upper section of the reaction shaft of the suspension smelting or suspension converting furnace. If this is not the case, the result is on the one hand an area of under-reacted concentrate, where there is more concentrate than the targeted process gas/concentrate ratio and, on the other hand an area of over-reacted concentrate, where there is less concentrate than the targeted process gas/concentrate ratio. Poor mixing results in poor slag quality, for example.

Poor distribution of concentrate also has an obvious effect on the temperature profile of the reaction shaft; hot areas are generated in the suspension smelting furnace, where the autogenous lining that is formed by the concentrate, protecting the reaction shaft, is subjected to greater thermal stresses and the result may in the worst case lead to the destruction of the reaction shaft wall. It has also been indicated that dust formation is more marked when the concentrate burner does not function properly due to poor concentrate distribution.

The patent specification WO 00/73519 discloses equipment for evening out the feed of powdery solid matter of the concentrate burner of the suspension smelting or suspension converting furnace.

Not Applicable.

BRIEF SUMMARY OF THE INVENTION

The object of the invention is to further improve the even feed of powdery solid matter.

The object of the invention is achieved by the arrangement for feeding powdery solid matter into a concentrate burner of a suspension smelting or suspension converting furnace.

Preferred embodiments of the arrangement according to the invention are described in the dependent claims.

The invention is based on the fact that the concentrate feed in the discharge pipe of the powdery solid matter is divided into four parts by means of a first partition and two second partitions, so that in the discharge pipe of the powdery solid matter four discharge pipe parts are formed for the concentrate, which preferably but not necessarily extend inside the annular concentrate discharge channel of the feeding means of the powdery solid matter of the concentrate burner. In a preferred embodiment, the first partition of the powdery solid matter discharge pipe is first adapted to divide the concentrate feed into two parts, the second partitions of the powdery solid matter discharge pipe thereafter being adapted so as to divide into two parts, so that the first partition and the second partitions divide the feed into four parts.

In a preferred embodiment, the first partition and the second partitions of the powdery solid matter discharge pipe extend inside the annular concentrate discharge channel of the concentrate burner up to the concentrate distributor in the middle of the annular concentrate discharge channel.

In a preferred embodiment, the annular concentrate discharge channel of the concentrate burner is provided with blades, which at least partially divide the annular concentrate discharge channel into sectors. In this preferred embodiment, the first partition of the powdery solid matter discharge pipe extends inside the annular concentrate discharge channel of the powdery solid matter feeding means up to the blade that divides the annular concentrate discharge channel into sectors, so that the blade and the first partition form an integral structure. In this preferred embodiment, each second partition of the powdery solid matter discharge pipe extends inside the annular concentrate discharge channel of the powdery solid matter feeding means up to the blade that divides the annular concentrate discharge channel into sectors, so that the blade and the second partition form an integral structure.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1shows an example of a suspension smelting or suspension converting furnace1, into which powdery solid matter (not shown in the figures), such as concentrate, slag forming agent and/or flue dust are fed through a concentrate burner2.

InFIG. 1, powdery solid matter is transferred to the upper section of the annular concentrate discharge channel4of the powdery solid matter feeding means3of the concentrate burner by means of the first powdery solid matter discharge pipe8, so that a powdery solid matter falls down as a continuous flow through the above-mentioned annular concentrate discharge channel4to the upper section of the reaction shaft5of the suspension smelting or suspension converting furnace1. InFIG. 1, reaction gas (not shown in the figures) is conveyed through reaction gas feeding means6from around an annular gas discharge channel9to the upper section of the reaction shaft5in the direction of the reaction shaft5.

FIG. 2shows in detail an apparatus for distributing powdery solid matter to the concentrate burner2, where the feed of both powdery solid matter and reaction gas are carried out from one direction. Powdery solid matter is conveyed by means of the first powdery solid matter discharge pipe8, preferably by an air slide conveyor, to the annular concentrate discharge channel4of the powdery solid matter feeding means3. In the middle of the annular concentrate discharge channel4, a concentrate distributor7is situated, the lower part of which being provided with holes (not marked with a reference number), through which dispersion gas that is fed horizontally (not shown) distributes concentrate flow outwards. The reaction gas feeding means6that are included in the concentrate burner2are connected to the annular gas discharge channel9, which surrounds the annular concentrate discharge channel4and from which reaction gas is discharged to the upper section of the reaction shaft5. The concentrate burner2thus comprises in its entirety the reaction gas feeding means6, the powdery solid matter feeding means3and the concentrate distributor7that is situated in the middle.

FIG. 5shows another apparatus for distributing powdery solid matter to the concentrate burner2, where, deviating fromFIG. 2, the feeds of both powdery solid matter and reaction gas are carried out from two directions: by means of two reaction gas feeding means6and the first powdery solid matter discharge pipe8and the second powdery solid matter discharge pipe19.

The object of the invention is, first, an arrangement for feeding powdery solid matter into the concentrate burner2of the suspension smelting or suspension converting furnace1, which burner can be used in the type of solution ofFIG. 1,2or5, for example.

The arrangement comprises the first powdery solid matter discharge pipe8.

Alternatively, the arrangement can have both the first powdery solid matter discharge pipe8and the second powdery solid matter discharge pipe19.

The concentrate burner comprises reaction gas feeding means6, powdery solid matter feeding means3and the concentrate distributor7.

The first powdery solid matter discharge pipe8and the possible second powdery solid matter discharge pipe19are provided with a first partition10, which divides the powdery solid matter feed for dividing the first powdery solid matter discharge pipe8and the possible second powdery solid matter discharge pipe19into two essentially similar discharge pipe parts11.

The powdery solid matter feeding means3of the concentrate burner2comprise an annular concentrate discharge channel4that surrounds the concentrate distributor7of the concentrate burner2.

The first partition10of the first powdery solid matter discharge pipe8and the possible second powdery solid matter discharge pipe19extends preferably, but not necessarily, inside the annular concentrate discharge channel4of the powdery solid matter feeding means3, as shown inFIGS. 4 and 7.

Each discharge pipe part11of the first powdery solid matter discharge pipe8and the possible second powdery solid matter discharge pipe19is at least partially divided into two discharge pipe portions15by a second partition13, so that four discharge pipe portions12are formed in the first powdery solid matter discharge pipe8and the possible second powdery solid matter discharge pipe19.

The second partitions13of the first powdery solid matter discharge pipe8and the possible second powdery solid matter discharge pipe19extend preferably, but not necessarily, inside the annular concentrate discharge channel4of the powdery solid matter feeding means3, as shown inFIGS. 4 and 7.

InFIGS. 4 and 7, the first partition10extends inside the annular concentrate discharge channel4of the powdery solid matter feeding means3up to the concentrate distributor7or to the close proximity of the concentrate distributor7or nearly into contact with the concentrate distributor7.

InFIGS. 4 and 7, the second partition13extends inside the annular concentrate discharge channel4of the powdery solid matter feeding means3up to the concentrate distributor7or to the close proximity of the concentrate distributor7or nearly into contact with the concentrate distributor7.

InFIGS. 4,7and8, the annular concentrate discharge channel4of the powdery solid matter feeding means3is provided with blades14, which divide the powdery solid matter feed and which at least partially divide the annular concentrate discharge channel4into sectors15. InFIG. 4, each discharge pipe portion12of the first powdery solid matter discharge pipe8ends in a respective sector18of the annular concentrate discharge channel4. InFIGS. 7 and 8, each discharge pipe portion12of the first powdery solid matter discharge pipe8and each discharge pipe portion12of the second first powdery solid matter discharge pipe19ends in a respective sector15of the annular concentrate discharge channel4.

The first partition10of the first powdery solid matter discharge pipe8and the first partition10of the possible second powdery solid matter discharge pipe19extend preferably, but not necessarily, inside the annular concentrate discharge channel4of the powdery solid matter feeding means3up to the blade14that divides the annular concentrate discharge channel4into sectors15, so that the blade14and the first partition10form an integral structure.

Each second partition13of the first powdery solid matter discharge pipe8and each second partition13of the possible second powdery solid matter discharge pipe19extend preferably, but not necessarily, inside the annular concentrate discharge channel4of the powdery solid matter feeding means3up to the blade that divides the annular concentrate discharge channel4into sectors15, so that the blade14and at least one second partition13form an integral structure.

InFIG. 4, the first partition10of the first powdery solid matter discharge pipe8extends throughout the length of the first powdery solid matter discharge pipe8and the second partitions13of the first powdery solid matter discharge pipe8extend over a portion of the first powdery solid matter discharge pipe8only, in other words, not throughout the length of the first powdery solid matter discharge pipe8.

InFIGS. 7 and 8, the first partition10of the first powdery solid matter discharge pipe8extends throughout the length of the first powdery solid matter discharge pipe8and the first partition10of the second powdery solid matter discharge pipe17extends throughout the length of the second powdery solid matter discharge pipe19, but the second partitions13of the first powdery solid matter discharge pipe8and the second powdery solid matter discharge pipe17only extend over a portion of the first powdery solid matter discharge pipe8and only over a portion of the second powdery solid matter discharge pipe19, respectively, in other words, not over the entire length of the first powdery solid matter discharge pipe8or the second powdery solid matter discharge pipe17. For example, in the arrangement ofFIG. 4, the first partition13of the first powdery solid matter discharge opening8is first adapted to divide the powdery solid matter feed into two parts, which the second partitions13of the first powdery solid matter discharge pipe8are thereafter adapted to divide into two parts, so that the first partition10and the second partitions13divide the powdery solid matter feed into four parts.

At least one discharge pipe portion12can be provided with a temperature sensor16for sensing a clogging in the discharge pipe portion12on the basis of the temperature of the discharge pipe portion12. Sensing the clogging by the temperature sensor16may, for example, be based on the fact that the temperature of the clogged discharge pipe portion12decreases, because the temperature of the concentrate in it decreases.

At least one discharge pipe portion12can be provided with additional gas feeding means (not shown). For example, additional gas feeding means can be used for feeding pressurized gas, such as pressurized air into the discharge pipe portion12, for example, for removing the observed clogging or, e.g., for feeding air into the discharge pipe portion12for creating a suspension of air and powdery solid matter.

At least one discharge pipe portion12comprises preferably, but not necessarily, an essentially vertical collision plate17next to the annular concentrate discharge channel4of the powdery solid matter feeding means3, which essentially vertical collision plate17the powdery solid matter is adapted to collide with and which is thus adapted to reduce the speed of the powdery solid matter. The arrangement comprises preferably, but not necessarily, at least one vertical collision plate17, which at least partly consists of blade14dividing the annular concentrate discharge channel4into sectors15. The arrangement comprises preferably, but not necessarily, at least one vertical collision plate17, the lower edge of which is designed18so as to distribute powdery solid matter evenly in the annular concentrate discharge channel4.

The arrangement may comprise at least one discharge pipe portion12that is provided with a vertical collision plate17having an upper plate section20for reducing the velocity of powdery solid matter, wherein the upper plate section20is perpendicular to the discharge pipe portion12, and having a lower plate section21for evenly distributing powdery solid matter in the annular concentrate discharge channel4, wherein the lower plate section21is turned about a vertical line in relation to the upper plate section20so that the lower plate section21lies within a plane parallel with a plane tangential to the pipe22of the concentrate distributor7that is arranged inside the annular concentrate discharge channel4.

The arrangement may comprise at least one discharge pipe portion12that is provided with a vertical collision plate17having an upper plate section20that is perpendicular to the discharge pipe portion12and having a lower plate section21that is turned about a vertical line in relation to the upper plate section20so that the lower plate section21is tangential to the pipe22of the concentrate distributor7that is arranged inside the annular concentrate discharge channel4. InFIG. 9the two pipe portions12in the middle are provided with a vertical collision plate17of this kind.

The arrangement may comprise at least one discharge pipe portion12that is provided with a vertical collision plate17having an upper plate section20that is perpendicular to the discharge pipe portion12and having a lower plate section23that is turned and curved about a vertical line in relation to the upper plate section20so that the lower plate section21is co-centric with the pipe23surrounding the annular concentrate discharge channel4. InFIG. 9the two outermost pipe portions12are provided with a vertical collision plate17of this kind.

FIGS. 5-8show an arrangement which in addition to the first powdery solid matter discharge pipe8comprises a second powdery solid matter discharge pipe19for feeding powdery solid matter into the powdery solid matter feeding means3of the concentrate burner2. As shown inFIGS. 7 and 8, the second powdery solid matter discharge pipe19is also provided with a first partition10for dividing the second powdery solid matter discharge pipe into two essentially similar discharge pipe parts11. The first partition10of the second powdery solid matter discharge pipe19can extend in a similar manner inside the annular concentrate discharge channel4of the powdery solid matter feeding means3, and each discharge pipe part11of the second powdery solid matter discharge pipe19is at least partly divided into two discharge pipe portions12by a second partition13, and the second partitions13can extend inside the annular concentrate discharge channel4of the powdery solid matter feeding means3.

FIGS. 5 and 6show an arrangement where the first powdery solid matter discharge pipe8and the second powdery solid matter discharge pipe19are connected at an essentially same height to the powdery solid matter feeding means3of the concentrate burner2. However, it is also possible that the first powdery solid matter discharge pipe8and the second powdery solid matter discharge pipe19are connected at different heights to the powdery solid matter feeding means3of the concentrate burner2.

FIG. 7shows an arrangement where the first powdery solid matter discharge pipe8and the second powdery solid matter discharge pipe19are connected diametrally to the powdery solid matter feeding means3.

FIG. 8shows an arrangement where the first powdery solid matter discharge pipe8is adapted at an angle with respect to the second powdery solid matter discharge pipe19.

It is obvious to those skilled in the art that with technology improving, the basic idea of the invention can be implemented in various ways. Thus, the invention and its embodiments are not limited to the examples described above but they may vary within the claims.

SEQUENCE LISTING

Not Applicable.