Suspension smelting furnace and a concentrate burner

The invention relates to a suspension smelting furnace comprising a reaction shaft (1), an uptake shaft (2), and a lower furnace (3), as well as a concentrate burner (4) for feeding reaction gas and fine solids into the reaction shaft (1) of the suspension smelting furnace. The concentrate burner (4) comprises a fine solids discharge channel (5) that is radially limited by the wall (6) of the solids discharge channel, a fine solids dispersion device (7) in the fine solids discharge channel (5), an annular reaction gas channel (8) that surrounds the fine solids discharge channel (5) and is radially limited by the wall (9) of the annular reaction gas channel (8), and a cooling block (10) that surrounds the annular reaction gas channel (8). The cooling block (10) is a component that is manufactured by a continuous casting method. The cooling block (10) is attached to the arch (11) of the reaction shaft (1) and the wall (9) of the annular reaction gas channel (8), so that the discharge orifice (12) of the annular reaction gas channel (8) is formed between a structure (13), which is jointly formed by the cooling block (10) and the wall (9) of the annular reaction gas channel (8), and the wall (6) of the solids discharge channel. The invention also relates to a concentrate burner (4) for feeding reaction gas and fine solids into the reaction shaft (1) of a suspension smelting furnace.

CROSS-REFERENCE TO RELATED APPLICATION

This is a national stage application filed under 35 USC 371 based on International Application No. PCT/FI2011/050614 filed Jun. 28, 2011, and claims priority under 35 USC 119 of Finnish Patent Application No. 20105741 filed Jun. 29, 2010.

BACKGROUND OF THE INVENTION

The invention relates to a suspension smelting furnace comprising a reaction shaft, an uptake shaft, and a lower furnace, as well as a concentrate burner for feeding reaction gas and fine-grained solids into the reaction shaft of the suspension smelting furnace.

The invention also relates to a concentrate burner for feeding reaction gas and fine-grained solids into the reaction shaft of a suspension smelting furnace.

Publication WO 98/14741 discloses a method for adjusting the flow velocity of reaction gas and the dispersion air of powdery solids, when feeding reaction gas and fine-grained solids into the reaction shaft of a suspension smelting furnace for creating a controlled and adjustable suspension. Reaction gas is fed into the furnace around a fine-grained solids flow, the solids being distributed with an orientation toward the reaction gas by means of dispersion air. The flow velocity and discharge direction of the reaction gas to the reaction shaft are smoothly adjusted by means of a specially shaped adjusting member which moves vertically in the reaction gas channel and by means of a specially shaped cooling block, which surrounds the reaction gas channel and which is located on the arch of the reaction shaft. The velocity of reaction gas is adjusted to a suitable level, irrespective of the gas quantity, in the discharge orifice located on the lower edge of the reaction shaft arch, from where the gas is discharged into the reaction shaft, forming a suspension with the powdery material therein, and the amount of the dispersion air which is used to disperse the material is adjusted according to the supply of the powdery material. The publication also discloses a multi-adjustable burner.

One problem with this known solution is the high price of the cooling block. It is usually manufactured from copper by sand casting. Sand casting, as a method, often leads to problems in quality, and a large amount of copper is consumed in making the cooling block.

SHORT DESCRIPTION OF THE INVENTION

The object of the invention is to solve the problems which are mentioned above.

The object of the invention is achieved by a suspension smelting furnace.

The suspension smelting furnace comprises a reaction shaft, an uptake shaft, and a lower furnace, as well as a concentrate burner for feeding reaction gas and fine solids into the reaction shaft of the suspension smelting furnace. The concentrate burner of the suspension smelting furnace comprises a fine solids discharge channel that is radially limited by the wall of the fine solids discharge channel, a fine solids dispersion device in the fine solids discharge channel, and an annular reaction gas channel that surrounds the fine solids discharge channel and that is radially limited by the wall of the annular reaction gas channel. The concentrate burner of the suspension smelting furnace further comprises a cooling block that surrounds the annular reaction gas channel.

In the suspension smelting furnace according to the invention, the cooling block is a component that is manufactured using a continuous casting method and that is attached to the arch of the reaction shaft and to the wall of the annular reaction gas channel, so that the discharge orifice of the annular reaction gas channel is formed between a structure, which is jointly formed by the cooling block and the wall of the annular reaction gas channel, and the wall of the fine solids discharge channel.

The invention also relates to a concentrate burner.

The concentrate burner comprises a fine solids discharge channel that is radially limited by the wall of the fine solids discharge channel, a fine solids dispersion device in the fine solids discharge channel, and an annular reaction gas channel that surrounds the fine solid matter discharge channel and that is radially limited by the wall of the annular reaction gas channel. The concentrate burner further comprises a cooling block that surrounds the annular reaction gas channel.

The cooling block in the concentrate burner according to the invention, is a component that is manufactured using a continuous casting method and that is attached with respect to the wall of the annular reaction gas channel, so that the discharge orifice of the reaction gas channel is formed between the structure, which is jointly formed by the cooling block and the wall of the annular reaction gas channel, and the wall of the fine solids discharge channel.

Preferred embodiments of the invention are disclosed in the dependent claims.

An advantage of the continuously-cast cooling block, when compared for example, with the solution of the publication WO 98/14741, is that a great deal less raw material, such as copper, is consumed in the manufacture and that the manufacturing process is also considerably easier. The continuously-cast cooling block provides improved protection against corrosions, which cause leaks, than a sand-cast cooling block.

The simple structure of the cooling block makes it considerably easier to install accessories and measuring devices that measure the process close to the concentrate burner. In a preferred embodiment, openings are formed in the cooling block for the feed-through of an outgrowth removal arrangement, such as the feed-through of outgrowth removal arrangement pistons.

In one solution according to the invention, the cooling block comprises drilled channels with the purpose of circulating cooling fluid in the cooling block.

DETAILED DESCRIPTION OF THE INVENTION

The invention relates to the suspension smelting furnace and the concentrate burner.

First, the suspension smelting furnace and some of its preferred embodiments and variations are described in more detail.

FIG. 1shows a suspension smelting furnace which comprises a reaction shaft1, an uptake shaft2, and a lower furnace3, as well as a concentrate burner4for feeding reaction gas (not shown in the figures) and fine solids (not shown) into the reaction shaft1. The operation of such a suspension smelting furnace is described in the Finnish patent FI22694, for example.

The concentrate burner4comprises a fine solids discharge channel5, which is radially, that is outwardly limited by the wall6of the fine solids discharge channel5.

The concentrate burner4comprises a fine solids dispersion device7in the fine solids discharge channel5.

The concentrate burner4comprises an annular reaction gas channel8, which surrounds the fine solids discharge channel5and which is radially limited by the wall9of the annular reaction gas channel8.

The concentrate burner4comprises a cooling block10that surrounds the annular reaction gas channel8.

The operation of such a concentrate burner4is described in the publication WO 98/14741, for example.

The cooling block10is a component that is manufactured using a continuous casting method.

The cooling block10is attached to the arch11of the reaction shaft1and to the wall9of the annular reaction gas channel8, so that the discharge orifice12of the annular reaction gas channel8is formed between a structure13, which is jointly formed by the cooling block10and the wall9of the annular reaction gas channel8, and the wall6of the fine solids discharge channel5.

The wall6of the fine solids discharge channel5preferably, but not necessarily, comprises a first curved portion14on the side of the annular reaction gas channel8, which is adapted so as to work in cooperation with the second curved portion15of the structure13on the side of the annular reaction gas channel8, which structure13is jointly formed by the cooling block10and the wall9of the annular reaction gas channel8, so that the flow cross-sectional area of the annular reaction gas channel8decreases in the flow direction of the reaction gas between the first curved portion14and the second curved portion15.

The wall6of the fine solids discharge channel and the structure13that is jointly formed by the cooling block10and the wall9of the reaction gas channel are preferably, but not necessarily, vertically movable with respect to each other, so that the size of the flow cross-sectional area of the discharge orifice12of the annular reaction gas channel8changes. For example, it is possible to vertically move the wall6of the fine solids discharge channel, so that the size of the flow cross-sectional area of the discharge orifice12of the reaction gas channel changes.

The annular reaction gas channel8can be provided with adjustable or fixed swirl vanes (not shown in the figures).

The cooling block10preferably, but not necessarily comprises channels17, such as drilled channels for the purpose of circulating cooling fluid (not shown) in the cooling block10.

The cooling block10is preferably, but not necessarily, provided with openings16for the feed-through of an outgrowth removal system (not shown).

The cooling block10is preferably, but not necessarily, at least partly manufactured of copper or a copper alloy.

The invention also relates to a concentrate burner4for feeding reaction gas and fine solids into the reaction shaft1of the suspension smelting furnace.

The concentrate burner4comprises a fine solids discharge channel5, which is radially, that is outwardly limited by the wall6of the fine solids discharge channel5.

The concentrate burner4comprises a fine solids dispersion device7in the fine solids discharge channel5.

The concentrate burner4comprises an annular reaction gas channel8, which surrounds the fine solids discharge channel5and which is radially, that is outwardly, limited by the wall9of the annular reaction gas channel8.

The concentrate burner4comprises a cooling block10that surrounds the annular reaction gas channel8.

The operation of such a concentrate burner4is described in the publication WO 98/14741, for example.

In the concentrate burner4, the cooling block10is a component that is manufactured by the continuous casting method.

The cooling block10is attached to the wall9of the annular reaction gas channel8, so that the discharge orifice12of the annular reaction gas channel8is formed between the structure13, which is jointly formed by the cooling block10and the wall9of the annular reaction gas channel8, and the wall6of the fine solids discharge channel5.

The wall6of the fine solids discharge channel5preferably, but not necessarily, comprises a first curved portion14on the side of the annular reaction gas channel8, which is adapted so as to work in cooperation with the second curved portion15of the structure13on the side of the annular reaction gas channel8, which structure13is jointly formed by the cooling block10and the wall9of the annular reaction gas channel8, so that the flow cross-sectional area of the annular reaction gas channel8decreases in the flow direction of the reaction gas between the first curved portion14and the second curved portion15.

The wall6of the fine solids discharge channel5and the structure13that is jointly formed by the cooling block10and the wall9of the annular reaction gas channel8are preferably, but not necessarily, vertically movable with respect to each other, so that the size of the flow cross-sectional area of the annular reaction gas channel8discharge orifice12changes. For example, it is possible that the wall6of the fine solids discharge channel5is vertically movable, so that the size of the flow cross-sectional area of the discharge orifice12of the annular reaction gas channel8changes.

The annular reaction gas channel8can be provided with adjustable or fixed swirl vanes (not shown in the figures).

The cooling block10preferably, but not necessarily, comprises channels17, such as drilled channels for the purpose of circulating cooling fluid (not shown) in the cooling block10.

The cooling block10is preferably, but not necessarily, provided with openings16for the feed-through the outgrowth removal system (not shown).

The cooling block10is preferably, but not necessarily, at least partly manufactured of copper or a copper alloy.

It is obvious to those skilled in the art that with the 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.