Title of Invention	UNIT TO PROCESS POWDERED LEAD-AND ZINC-BEARING RAW MATERIALS
Abstract	The unit to process powdered lead- and zinc-bearing raw materials is relative to non-ferrous metallurgy, mainly to facilities to process powdered lead- and zinc-bearing raw material that can contain copper and noble metals. The objective of the invention is simultaneous increase of lead direct recovery into lead bullion and of unit specific capacity. The unit to process powdered lead- and zinc-bearing raw materials includes the vertical smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition wall with water cooled copper elements, separating the smelting chamber from the gas cooler shaft, the electric furnace separated from the smelting chamber by the partition with water cooled copper elements, the jacketed belt, facilities to tap smelting products, the hearth. No more than two tuyeres can be installed at a level of the partition lower edge, separating the gas-cooler shaft from the smelting chamber with a slope to the hearth at an angle to horizontal plane (Fig 1). In case of installation of two tuyeres they are to be arranged one on each opposite side wall of the gas cooler shaft with mirror-like shift relatively to its axial cross-section of the gas cooler shaft, the ratio of which towards inside length of the gas cooler shaft amounts to 0.25-0.30.

Title of Invention

UNIT TO PROCESS POWDERED LEAD-AND ZINC-BEARING RAW MATERIALS

Abstract

The unit to process powdered lead- and zinc-bearing raw materials is relative to non-ferrous metallurgy, mainly to facilities to process powdered lead- and zinc-bearing raw material that can contain copper and noble metals. The objective of the invention is simultaneous increase of lead direct recovery into lead bullion and of unit specific capacity. The unit to process powdered lead- and zinc-bearing raw materials includes the vertical smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition wall with water cooled copper elements, separating the smelting chamber from the gas cooler shaft, the electric furnace separated from the smelting chamber by the partition with water cooled copper elements, the jacketed belt, facilities to tap smelting products, the hearth. No more than two tuyeres can be installed at a level of the partition lower edge, separating the gas-cooler shaft from the smelting chamber with a slope to the hearth at an angle to horizontal plane (Fig 1). In case of installation of two tuyeres they are to be arranged one on each opposite side wall of the gas cooler shaft with mirror-like shift relatively to its axial cross-section of the gas cooler shaft, the ratio of which towards inside length of the gas cooler shaft amounts to 0.25-0.30.

Full Text	Unit to process powdered lead- and zinc-bearing raw materials Technical field The invention is relative to non-ferrous metallurgy, mainly to facilities to process powdered lead- and zinc-bearing raw materials that can contain copper and noble metals. The most important tasks while improving units for processing of lead- and zinc-bearing raw materials that except lead can contain zinc, copper and other valuable elements, are increased recovery of metals into marketable products, the process intensification at expanding the spectrum of raw material processed including lead-bearing materials produced as by-products in other industrial processes the storage of which presents significant ecological hazard. There is an extensive group of lead-bearing materials such as hydrometallurgical processes residues, converting dusts of copper mattes, slurries of neutralization and technological solutions purification that are not processed or processed in insufficient volume in well-known units so they are accumulated in dumps. In addition to lead, all above mentioned materials contain considerable amount of zinc and copper that reduces recovery complexity of non-ferrous metals from natural mineral raw material. Prior art There is known the unit to process powdered lead- and zinc-bearing raw materials, wherein there is a vertical smelting chamber of rectangular cross-section with a burner, gas cooler, vertical cooled partition-wall separating the smelting chamber from the gas cooler, electric furnace separated from the smelting chamber by the vertical cooled partition-wall, jacketed belt, facilities to tap smelting products and the hearth. Thereby the ratio between levels difference of partition lower edges and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.30 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.23. (Slobodkin L.V. New technology at lead plant UKSZK//Non-ferrous metals, 1987, #9, p. 20-22). The disadvantage of this unit is low direct recovery of lead into lead bullion, resulting from high charge dust entrainment from the smelting chamber together with reaction gases at indicated ratios of the unit structural components. Increased content of recycle sulphate dusts in charge (at continuous return of these dusts through the burner to roasting-smelting) leads to the decrease of flame melt temperature and the decrease of speed and degree of lead oxide reduction in the layer of carbon reductant associated with it. The closest technical substance of the invention is the unit for processing of powdered lead- and zinc-bearing raw material wherein there is a vertical smelting chamber of rectangular cross-section with the burner, the gas cooler, the partition-wall separating the smelting chamber from the gas cooler, the electric furnace separated from the smelting chamber by the partition-wall, jacketed belt, facilities to tap smelting products and the hearth. Thereby the ratio between levels difference of partitions lower edges and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.15-0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.25-2.10. (Patent of Kazakhstan Republic #8705, MPK F27B 17/00, C22B 13/02, published 15.04.2005, Bulletin #4). The disadvantage of this unit is simultaneous reduction of the unit specific capacity and direct recovery of lead into lead bullion resulting from slag melt dead zone at outer end wall of the gas cooler shaft opposite the partition, separating it from the smelting chamber. Self-cooling of slag melt in this unit area causes crusts formation and decrease in slag melt circulation intensity between the electric furnace, the smelting chamber and the gas cooler shaft. It reduces heat input from the electric furnace to the layer of carbon reductant and results in the slow-up of flame melt carbothermic reduction process. Engineering problem of the present invention is simultaneous increase of direct lead recovery into lead bullion and improvement of the unit specific capacity at the expense of slowdown of the process of crust formation on the walls of gas cooler shaft bottom area, speed-up of circulation and increase of heat content of slag melt flow, providing additional heat input into the layer of carbon reductant and the corresponding speed-up of flame melt reduction process. This problem can be solved by organization of intensive heat input into the slag melt bath under the gas cooler shaft. Abstract of the disclosure The assigned task is achieved by that in the known unit for processing of powdered lead- and zinc-bearing raw material, wherein there is the vertical smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition-wall with water-cooled copper elements separating the smelting chamber from the gas cooler shaft, the electric furnace separated from the smelting chamber by the partition-wall with water-cooled copper elements, jacketed belt, facilities to tap smelting products and the hearth. Thereby the ratio between levels difference of partitions lower edges and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.15-0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.25- 35 2.10. According to the invention on the gas cooler shaft walls no more than two tuyeres can be installed at a level of the partition lower edge, separating the gas-cooler shaft from the smelting chamber with the a slope to the hearth at an angle to horizontal plane, determined by the following formula (Formula Removed) wherein a - tuyeres slope angle; k - coefficient of tuyeres slope angle, equaled to 1.11 -1.25; AH - difference of partitions lower edges levels; B - inside width of the gas cooler shaft. It is reasonable as per the invention that while installing two tuyeres they are to be arranged one on each opposite side wall of the gas cooler shaft with mirror-like shift relatively to its axial cross-section of the gas cooler shaft, the ratio of which towards inside length of the gas cooler shaft amounts to 0.25-0.30. The installation of tuyeres and their arrangement allow to supply oxygen-containing gas onto the surface of carbon material layer, floating on slag melt bath in the bottom area of the gas cooler shaft, where reaction gases from the smelting chamber are supplied. It gives opportunity to afterburn carbon monoxide, contained in reaction gases of the smelting chamber as a result of reduction reactions of oxide melt in the layer of carbon reductant, floating on slag melt bath under the burner flame of the smelting chamber as well as opportunity of incomplete burning of solid carbon fuel in the flame, introduced into the charge at low calorific capacity of the processed raw material. At insignificant amount of carbon monoxide contained in the smelting chamber reaction gases, oxygen introduced through tuyeres together with oxygen-containing gas, is consumed for burning of solid carbon in the layer of carbon material floating on slag melt bath in the bottom area of the gas cooler shaft. At carbon monoxide burning, contained in the smelting chamber reaction gases or at burning of solid carbon in the layer of carbon material, floating on slag melt bath in the bottom area of the gas cooler shaft, the heat is evolved, the portion of it goes to increase the temperature of slag melt in this dead zone of the unit. The increase of slag melt temperature prevents crusts formation on the bottom part of the gas cooler shaft walls and speeds up circulation of slag melt flow between the electric furnace, the smelting chamber and the gas cooler shaft simultaneously increasing its heat content. It leads towards increase in heat input into the working area of carbon reductant layer under the burner with circulating flow of slag melt and the corresponding speed-up of flame melt reduction. As a result the direct recovery of lead into lead bullion is increased and the possibility of the unit specific capacity improvement is provided. 35 is provided. The increase of direct recovery of lead into lead bullion and simultaneous increase of the unit specific capacity are provided at the expense of the reduction of dust entrainment and correspondingly the reduction of recycle sulphate dusts content in charge, going to the burner due to tuyeres slope to the unit hearth. Injection of oxygen-containing gas through tuyeres with down-directed flow velocity component into the flow of reaction gases, going out from the smelting chamber causes their slowdown at the entrance of the gas cooler shaft and increases the velocity of dust particles precipitation, carried out by reaction gases from the smelting chamber. At installation of tuyeres on gas cooler shaft walls at the level lower than the level of the partition lower edge that separates the gas cooler shaft from the smelting chamber the effect of heat release at the surface of slag melt remains. However, the portion of reaction gases begins to go over the flow of oxygen-containing gas injected through tuyeres. It leads to reduction of reaction gases slowdown effect and the decrease in velocity of dust particles precipitation, carried out by reaction gases from the smelting chamber. Moreover, the approaching of oxygen-containing gas jet from tuyeres to the surface of slag bath will result in increase of already settled dust particles carry-over. As a result, smelting dusts output and their portion in charge will increase and the flame temperature, the rate of oxide melt reduction in the layer of carbon reductant, direct lead recovery into lead bullion and the unit specific capacity will reduce. At installation of tuyeres at the level higher than the level of the partition lower edge the area of heat release moves away from the slag melt surface. Moreover, at insufficient content of carbon monoxide in reaction gases of the smelting chamber the higher level of tuyeres installation leads to reduction of the contact between oxygen-containing gas and the layer of carbon material. It will reduce heat input into slag bath under the gas cooler shaft. As a result, there will be reduced heat content and intensity of slag melt flow circulation between the electric furnace, the smelting chamber and the gas cooler shaft that will lead to slow-up of heat input into the working area of the layer of carbon reductant under the burner. Correspondingly, there will be the decrease in velocity of the flame melt reduction, in direct recovery of lead into lead bullion and in the unit specific capacity. At the setting of tuyeres slope at an angle to horizontal plane with k coefficient, that is less than 1.11, the area of heat release from afterburning of carbon monoxide in reaction gases of the smelting chamber will move away from the slag melt surface. Moreover, oxygen-containing gas injected through tuyeres during some time of the unit operation time after slag tapping won't be in contact with the layer of carbon material in the gas cooler shaft. As a 35 result, total flow of heat into slag bath under gas cooler shaft will be reduced. It will reduce the effect of the process of crusts formation slowdown on the bottom part of the gas cooler shaft walls as well as the intensity of slag melt flow circulation between the electric furnace, the smelting chamber and the gas cooler shaft and its heat content. Thereby, there will be reduced heat input into the layer of carbon reductant under the flame of the burner and simultaneously the rate of flame melt reduction. As a result, direct lead recovery into lead bullion and the unit specific capacity will be reduced. Additional reduction of the direct lead recovery into lead bullion and the unit specific capacity in this case is stipulated by the velocity reduction of dust particles precipitation, carried out by reaction gases from the smelting chamber. Thereby, there will be the increase of smelting dusts output and their portion in charge and the temperature of flame and the rate of oxide melt reduction in the layer of carbon reductant will be reduced. As a result, there will be a simultaneous decrease in the direct lead recovery into lead bullion and the unit specific capacity. At the setting of tuyeres slope to the hearth at an angle to horizontal plane with k coefficient, that is more than 1.25, as well as in the case of tuyeres installation at the level lower than the level of the partition lower edge that separates the gas cooler shaft from the smelting chamber, the part of reaction gases will begin to go over the flow of oxygen-containing gas injected through tuyeres. It leads to reduction of reaction gases slowdown effect and the decrease in velocity of dust particles precipitation, carried out from the smelting chamber. Moreover, the increase of tuyeres slope angle to the surface of slag bath will result in blowing-out of the already settled dust particles and in spattering of fine drops of slag melt into the flow of upward reaction gases. As a result, output of smelting dusts and their portion in charge will increase and the flame temperature and the rate of oxide melt reduction in the layer of carbon reductant will decrease. Therefore, direct lead recovery into lead bullion and the unit specific capacity will decrease too. At installation of two tuyeres, one on each side wall of the gas cooler shaft with mirror-like shift relatively to its axial cross-section, the effect of assigned task achievement is improved. It is determined by the following two factors. Firstly, the installation of two tuyeres axes of which are mirror-like shifted relatively to its axial cross-section of the gas cooler shaft leads to the increase of surface of heat transfer to slag bath from burning of carbon monoxide reaction gases of smelting chamber or from solid carbon burning in the layer of carbon reductant. Correspondingly, at the same thermal effect from reaction gases afterburning or from burning of solid carbon in the layer of carbon reductant on the surface of slag melt, heat gain to slag bath volume under the gas cooler shaft increases. The increase of heat content of slag melt results in speed-up of its circulation and 35 increase of heat gain into the area of reduction reactions flow. The result is additional increase of direct lead recovery into lead bullion and improvement of the unit specific capacity. Secondly, the installation of two tuyeres, one on each side wall of gas cooler shaft with mirror-like shift relatively to its axial cross-section leads to additional effect of the increase of direct lead recovery into lead bullion and the unit specific capacity at the expense of dust entrainment and correspondingly, the increase of recycle sulphate dusts content in charge, entering to the burner. The decrease of dust entrainment in this case is stipulated by the injection of oxygen-containing gas through two tuyeres, installed on opposite side walls of the gas cooler shaft and mirror-like shifted relatively to its axial cross-section, and leads to spinning of the gas cooler shaft upward flow of reaction gases going out from smelting chamber. As a result, there is centrifugal component of particles velocity promoting their complete precipitation on gas cooler shaft walls. The effect of set up task achievement is enhanced at the increase of distance from each tuyere up to the axial cross-section of the gas cooler shaft. It is stipulated by the enlargement of the total heat transfer surface between the area of heat release from reaction gases afterburning or burning of solid carbon and of slag bath. Correspondingly, there is an increase of heat gain into slag bath volume, the increase of its heat content and of slag melt circulation velocity in this area of the unit. It leads to the increase of heat intake to the area of reduction reactions and their speed up. The result of it is increase of direct lead recovery and of specific capacity. Moreover, the increase of the distance between tuyeres axes strengthens the effect of spinning of the gas cooler shaft upward flow of reaction gases that leads to more complete precipitation of dust particles on gas cooler shaft walls. The strongest effect is achieved at tuyeres axes distance from axial cross-section of the gas cooler shaft the ratio of which to its inside length amounts to 0.25-0.30. At this distance there is achieved the maximum contact surface of heat release area and slag melt bath, as far as flows of burning gases from opposite tuyeres stop to shut. Moreover, at this distance there is achieved the noticeable effect of spinning of reaction gases upward flow and the speed up of precipitation of dust particles on gas cooler shaft walls without overheating of jackets by flows of burning gases from afterburning of carbon monoxide (or burning of solid carbon on the surface of carbon material layer). At the distance of tuyeres axes from the gas cooler shaft axial cross-section the ratio of which to its inside length is less than 0.25, the heat exchange surface of hot gases and slag bath and the effect of spinning of upward reaction gases are decreased. As a result, there is a simultaneous decrease of heat flow, transferred to the volume of slag melt bath, and of degree of dust particles precipitation on the gas cooler shaft walls. Correspondingly, there is the 35 decrease of effect of additional slag melt heat content increase of the corresponding speed up of its circulation in slag bath as well as of the effect of reduction of recycle sulphate dusts entrainment from the unit. Thus, the blowing through tuyeres does not result in maximum possible enhancement of the effect of the unit specific capacity increase as well as of the direct lead recovery into lead bullion at the expense of heat input increase into the area of reduction reactions flowing with flame melt and melt flow circulating in slag bath, that would provide the speed up of oxide melt reduction in the layer of carbon reductant. At the distance of tuyeres axes from the gas cooler shaft axial cross-section the ratio of which to the inside length of the gas cooler shaft is more than 0.30, the effect of heat transfer from burning gases into slag melt bath and effect of spinning of upward reaction gases, determining the degree of dusts precipitation on gas cooler shaft walls are not increased. However, high-temperature burning area of carbon monoxide in reaction gases and of solid carbon in carbon layer is approaching to the unit walls noticeably increasing specific heat load on jacketed belt in that local area and increasing thereby the probability of jackets burning-out. The invention is illustrated by drawings. On Figure 1 there is a unit to process powdered lead- and zinc-bearing raw materials, general view; on Figure 2 and Figure 3 -sections AA and BB of the gas cooler shaft, presented on Figure 1 at installing one tuyere; on Figure 4 - section BB of the gas cooler shaft presented on Figure 1 at installing two tuyeres. The unit consists of a vertical smelting chamber 1 of rectangular cross-section, in the roof of which the burner 2 for feeding of charge, oxygen, recycle dusts and solid reductant is installed, partitions 3 with water-cooled copper elements, that installed vertically and dividing the smelting chamber 1 from the gas cooler shaft 4 on side wall of which tuyeres 5, 6 for oxygen-containing gas supply are installed, the electric furnace 7, adjacent to the smelting chamber and separated from it by the vertical partition 8 with water-cooled copper elements, total for the smelting chamber, the electric furnace and the hearth gas cooler shaft 9, the jacketed belt 10 and facilities to tap smelting products 11. The unit operates in the following way. Powdered charge, composed from lead and lead-zinc raw material (lead, lead-zinc, lead-copper, lead-copper-zinc, lead-silver concentrates, lead dusts, lead-bearing residues, lead bullion refining recycles, battery paste and other secondary lead materials), fluxes and, if necessary, solid carbon fuel (coke, petroleum coke, black, brown or charcoal) after drying to moisture content less than 1% is mixed with crushed carbon reductant (coke, petroleum coke, black or charcoal) and transferred to the burner 2 (see Figure 1) through which by the flow of process oxygen (94-99% O2) is blown into the smelting chamber 1 of the unit. In the smelting chamber 1 under the effect of radiation from flame and high temperatures of upward furnace 35 gases (T=1100-1200°C) charge is ignited, oxidized and smelted in suspended state with production of disperse oxide melt. In bottom part of the smelting chamber 1, flame temperature is achieved 1350-1450°C. The degree of charge desulphurization is controlled by the change of ratio of charge and oxygen consumption in the burner 2. Crushed carbon reductant transferred together with charge (that is coke, petroleum coke, black or charcoal) with the grain size from 5-20 mm is heated while it is moving to the flame and then it gets onto the surface of slag bath. The presence in the construction the partition 8, arranged downward from the furnace roof and partly submerged into slag melt allows to divide gas space of the smelting chamber 1 and the electric furnace 7 and to form on the surface of slag bath under the burner flame a porous layer of carbon reductant of required height. It provides reduction of non-ferrous metals losses in slag melt at the expense of reduction atmosphere creation in the electric furnace and speed up of small particles of reduced metals precipitation into bottom metallic phase, resulting from their coagulation and coarsening of carbon reductant layer in porous structure. Disperse oxide melt formed in the process of flash smelting goes onto a porous layer of crushed carbon reductant and leaking through it is undergone selective reduction. Lead oxides are reduced to metallic lead and zinc oxides are remained in slag melt, which together with metallic lead flows under the partition 8 from the smelting chamber 1 into the electric furnace 7 serving for accumulation and settling of smelting products with their separation by specific weight and if necessary - for partial tapping of zinc from slag melt by feeding small-sized carbon reductant on the surface of slag bath of the electric furnace. Copper oxides, similar to lead oxides are reduced in the layer of carbon reductant to metal and transferred to lead bullion, non-ferrous metals sulfides presented in disperse flame melt either divided between metallic or slag phases at charge desulphurization degree more than 90-94% or at less degree of charge desulphurization they form individual matte phase, forming in the process of smelting products settling in the electric furnace. It allows conducting rough decoppering of lead bullion with recovering of copper excess from processed lead- and zinc-bearing raw material to polymetallic matter directly in the unit. Part of heat energy, released from the electric furnace together with circulating flow of slag melt of total slag bath goes to the smelting chamber and partly soaked by the layer of carbon reductant. Together with heat flow, going with flame melt, heat gain from the electric furnace allows compensate heat consumption by endothermal reactions of oxides reduction in porous carbon layer. Slag and lead are tapped through the facilities 11 from the electric furnace 7 and then transferred to processing to produce marketable products. 35 Sulfur dioxide reaction gases from the smelting chamber 1, formed during charge flash smelting go under the partition 3 arranged downward from the furnace roof that doesn't come to the surface of slag melt and then go for cooling into the gas cooler shaft 4. In the bottom part of the gas cooler shaft 4 reaction gases, containing carbon monoxide, are afterburnt at the expense of oxygen-containing gas supply through tuyeres 5, 6. Part of heat energy, released hereby is absorbed by flow of slag melt circulating in the total unit slag bath and goes to the smelting chamber into the layer of carbon reductant adding the heat flow going with flame melt and slag melt from the electric furnace. It enhances possibility to compensate heat consumption by endothermal reactions of oxides reduction in porous carbon layer. Reaction gases depleted by carbon monoxide go upward to the gas cooler shaft outlet and are cooled at the expense of heat exchange with water-cooled surfaces of shaft walls. After the gas cooler 4 gases are purified in the electrostatic precipitator (it is not shown on drawings) and then go for sulphur utilization with production of marketable products (sulphuric acid, elemental sulphur, sulphuric anhydride or salts). Dust, captured by the electrostatic precipitator, is continuously returned for smelting. The invention is illustrated by the unit operation examples. Example 1 (by prototype). In the pilot unit of KIVCET (the smelting chamber cross-sectional area - 1.4 m2, the smelting chamber height - 3.3 m, the gas cooler shaft cross-sectional area - 1.44 m2, the electric furnace hearth area - 5 m2, generating capacity of the electric furnace transformer - 1200 kW) having difference ratio between partitions lower edges levels and the distance from smelting chamber roof to partition lower edge, separating the electric furnace from the smelting chamber, that equaled 0.28 and ratio between distance from partition lower edge, separating the electric furnace from the smelting chamber up to the hearth and the difference of partitions lower edges levels, equaled 1.25 there was conducted processing of charge, prepared from sulphide lead concentrates, lead dusts, lead-bearing residues of zinc production, battery paste, quartz and lime fluxes of the following composition, %: 34.0 of lead, 9.6 of zinc, 1.1 of copper, 12.3 of iron, 10.2 of sulphur, 8.4 of silicon dioxide, 4.1 of calcium oxide. To compensate low calorific capacity of charge there was introduce into it powdered coal of the composition, %: 42.5 of solid carbon, 28.0 of volatiles and 30.0 of ash, containing, %: 9.0 of iron, 55.8 of silicon dioxide and 4.5 of calcium oxide. As a reductant there was used coke breeze, containing %: 85.5 of carbon, 1.3 of iron, 7.2 of silicon dioxide, 1.3 of calcium oxide. In the course of tests there was processed 50 t of charge. Obtained results of the unit operation are given in Table 1 - Comparison of prototype operation figures and proposed unit with one tuyere. 35 Example 2. Tests were conducted in modernized in accordance with the declared invention (claim 1) pilot unit of KIVCET that had parameters and conditions as in Example 1. Thereby the tuyere was installed on side wall of the gas cooler in flat surface of its axial cross-section at the level of partition lower edge, separating the gas cooler shaft from the smelting chamber, with a slope to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.2. Totally there was processed 48 t of charge. Example 3. Tests were conducted under similar conditions as in Example 2, but tuyere was shifted downward from the partition lower edge level, separating the gas cooler shaft from the smelting chamber at the distance of Ah, ratio of which to difference of partitions lower edges levels AH amounted to 0.2. Example 4. Tests were conducted under similar conditions as in Example 2, but the tuyere was shifted upward from the partition lower edge level, separating the gas cooler shaft from the smelting chamber at the distance of Ah, ratio of which to difference of partitions lower edges levels AH amounted to 0.2 Example 5. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.11. Example 6. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.25. Example 7. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.00. Example 8. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.30. Example 9. Tests were conducted under similar conditions as in Example 2, but the tuyere was installed on end wall of the gas cooler shaft in flat surface of its longitudinal axial section with a slope to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.20. Tests results by Examples 1 -9 are given in Table 1. Example 10. Tests were conducted under similar conditions as in Example 2, but two tuyeres were installed to supply oxygen-containing gas, one each opposite side wall of the gas cooler. Tuyeres were installed in one flat surface of axial cross-section of gas cooler shaft on the level of partition lower edge, separating the gas cooler shaft from the smelting chamber the level of partition lower edge, separating the gas cooler shaft from the smelting chamber with a slope to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.20. Example 11. Tests were conducted under similar conditions as in Example 2, but two tuyeres were installed as in Example 10, the difference was that one of tuyeres was shifted from axial cross-section plane of the gas cooler shaft at the distance of Al, the ratio of which to shaft inside length L amounted to 0.27. Example 12. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length -∆l/L amounted to 0.20. Example 13. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length - ∆l/L amounted to 0.25. Example 14. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length - ∆l/L amounted to 0.27. Example 15. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length - Al/L amounted to 0.30. Example 16. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of gas cooler shaft at the distance, the ratio of which to its inside length - ∆l/L amounted to 0.35. The unit operation figues of Examples 10-16 are given in Table 2 (Comparison of operation figures of proposed unit with one and two tuyeres) in comparison with figures of Example 2 of Table 1. As it is seen from data comparison of Examples 1 and 2-9 in Table 1, proposed unit in comparison with prototype allows increase of lead direct recovery into lead bullion by 3.03-3.06 relative % and increase of the unit specific capacity by 0.4-0.6 relative %. It is shown that the use of the proposed level of tuyeres installation and slope angle range to the hearth provides achievement of higher figures of lead direct recovery into lead bullion and of the unit 35 provides achievement of higher figures of lead direct recovery into lead bullion and of the unit specific capacity (compare Examples 2, 5 and 6 with Examples 3, 4, 7 and 8). It is shown also that choice of the gas cooler shaft wall at installation of one tuyere to supply oxygen-containing gas practically does not influence the unit operation figures (compare Examples 2 and 9). Installation of two tuyeres, one on each opposite side wall of gas cooler shaft does not improve the unit operation figures in comparison with the variant of one tuyere installation in case if each of these tuyeres is situated in one and the same cross-section of the gas cooler shaft (compare Examples 2 and 10 of Table 2). The shift of tuyeres axes that is not mirror-like relative to axial cross-section of the gas > cooler shaft gives improvement of the unit operation figures but does not provide the achievement of maximum possible additional effect in solution of assigned task (compare Examples 2 and 11 with Examples 13-15 in Table 2). Mirror-like tuyeres shift relatively to axial cross-section of the gas cooler shaft with the use of proposed range of distance ratios from tuyeres axes up to axial cross-section of gas cooler shaft to its inside length (0.25-0.30) gives additional increase of lead direct recovery by 0.13 relative % and increase of the unit specific capacity by 0.33 relative % relatively to the variant of one tuyere use (compare Examples 12 and 13-15). The reduction of this ratio of less proposed range of 0.25 reduces lead direct recovery and the unit specific capacity approaching these figures to the variant of the unit operation with one tuyere (compare Examples 12 and 2). The increase of this ratio of more proposed range of 0.30 does not result in further improvement of the unit operation figures (compare Examples 15-16), but noticeably increases possibility of thermal damage of jackets at the expense of high-temperature area of smelting camber reaction gases afterburning approaching to them. Moreover, as is seen from Tables 1 and 2, the present invention allows to reduce specific expenses on electric power by 6.2-6.8 relative % and to increase the unit useful time by 3-5% at the expense of heating-up of slag bath area under the gas cooler shaft, that provides slowdown of the process of crusts formation in this unit area. The unit to process powdered lead- and zinc-bearing raw materials includes the vertical smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition wall with water cooled copper elements separating smelting chamber from the gas cooler shaft, the electric furnace separated from the smelting chamber by the partition with water cooled copper elements, the jacketed belt, facilities to tap smelting products, the hearth, herewith, ratio difference between the partition lower edges levels and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.15-0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.25-2.10 differing by fact that on the gas cooler shaft walls there are no more than two tuyeres installed that are on the level of partition lower edge, separating the electric furnace from the smelting chamber with a slope to the hearth at an angle to horizontal plane, determined by the following formula: a = arctg (k-∆H/B), wherein - ά - tuyeres slope angle; k - coefficient of tuyeres slope angle, equaled to 1.11-1.25; ∆H - difference of partition lower edges levels; B - inside width of gas cooler shaft. Table 1. Comparison of prototype operation figures and proposed unit with one tuyere. (Table Removed) Table 2. Comparison of operation figures of proposed unit with one and two tuyeres (Table Removed) We claim:- 1. The unit to process powdered lead- and zinc-bearing raw materials includes the vertical smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition wall with water cooled copper elements separating smelting chamber from the gas cooler shaft, the electric furnace separated from the smelting chamber by the partition with water cooled copper elements, the jacketed belt, facilities to tap smelting products, the hearth, herewith, ratio difference between the partition lower edges levels and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.15- 0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.25-2.10 differing by fact that on the gas cooler shaft walls there are no more than two tuyeres installed that are on the level of partition lower edge, separating the electric furnace from the smelting chamber with a slope to the hearth at an angle to horizontal plane, determined by the following formula (Formula Removed) wherein - a - tuyeres slope angle; k - coefficient of tuyeres slope angle, equaled to 1.11-1.25; ∆H-difference of partition lower edges levels; B - inside width of gas cooler shaft. 2. The unit to process powdered lead- and zinc-bearing raw materials by claim 1 differs by the fact'that at installation of two tuyeres they are arranged by one on each opposite side wall of the gas cooler shaft with mirror-like shift relative to its axial cross-section. 3. The unit to process powdered lead- and zinc-bearing raw materials by claims 1, 2, differs by fact that at installation of two tuyeres each of them is arranged at the distance from axial cross-section of gas cooler shaft, the ratio of which to inside length of the gas cooler shaft amounts to 0.25-0.30. 4. Unit to process powdered lead- and zinc-bearing raw materials as claimed in any of the above claims substantially as described in the specification and illustrated in the accompanying drawings.

Full Text

Unit to process powdered lead- and zinc-bearing raw materials
Technical field
The invention is relative to non-ferrous metallurgy, mainly to facilities to process powdered lead- and zinc-bearing raw materials that can contain copper and noble metals.
The most important tasks while improving units for processing of lead- and zinc-bearing raw materials that except lead can contain zinc, copper and other valuable elements, are increased recovery of metals into marketable products, the process intensification at expanding the spectrum of raw material processed including lead-bearing materials produced as by-products in other industrial processes the storage of which presents significant ecological hazard.
There is an extensive group of lead-bearing materials such as hydrometallurgical processes residues, converting dusts of copper mattes, slurries of neutralization and technological solutions purification that are not processed or processed in insufficient volume in well-known units so they are accumulated in dumps. In addition to lead, all above mentioned materials contain considerable amount of zinc and copper that reduces recovery complexity of non-ferrous metals from natural mineral raw material.
Prior art
There is known the unit to process powdered lead- and zinc-bearing raw materials, wherein there is a vertical smelting chamber of rectangular cross-section with a burner, gas cooler, vertical cooled partition-wall separating the smelting chamber from the gas cooler, electric furnace separated from the smelting chamber by the vertical cooled partition-wall, jacketed belt, facilities to tap smelting products and the hearth. Thereby the ratio between levels difference of partition lower edges and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.30 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.23. (Slobodkin L.V. New technology at lead plant UKSZK//Non-ferrous metals, 1987, #9, p. 20-22).
The disadvantage of this unit is low direct recovery of lead into lead bullion, resulting from high charge dust entrainment from the smelting chamber together with reaction gases at indicated ratios of the unit structural components. Increased content of recycle sulphate dusts in charge (at continuous return of these dusts through the burner to roasting-smelting) leads to the decrease of flame melt temperature and the decrease of speed and degree of lead oxide reduction in the layer of carbon reductant associated with it.
The closest technical substance of the invention is the unit for processing of powdered

lead- and zinc-bearing raw material wherein there is a vertical smelting chamber of rectangular cross-section with the burner, the gas cooler, the partition-wall separating the smelting chamber from the gas cooler, the electric furnace separated from the smelting chamber by the partition-wall, jacketed belt, facilities to tap smelting products and the hearth. Thereby the ratio between levels difference of partitions lower edges and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.15-0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.25-2.10. (Patent of Kazakhstan Republic #8705, MPK F27B 17/00, C22B 13/02, published 15.04.2005, Bulletin #4).
The disadvantage of this unit is simultaneous reduction of the unit specific capacity and direct recovery of lead into lead bullion resulting from slag melt dead zone at outer end wall of the gas cooler shaft opposite the partition, separating it from the smelting chamber. Self-cooling of slag melt in this unit area causes crusts formation and decrease in slag melt circulation intensity between the electric furnace, the smelting chamber and the gas cooler shaft. It reduces heat input from the electric furnace to the layer of carbon reductant and results in the slow-up of flame melt carbothermic reduction process.
Engineering problem of the present invention is simultaneous increase of direct lead recovery into lead bullion and improvement of the unit specific capacity at the expense of slowdown of the process of crust formation on the walls of gas cooler shaft bottom area, speed-up of circulation and increase of heat content of slag melt flow, providing additional heat input into the layer of carbon reductant and the corresponding speed-up of flame melt reduction process. This problem can be solved by organization of intensive heat input into the slag melt bath under the gas cooler shaft.
Abstract of the disclosure
The assigned task is achieved by that in the known unit for processing of powdered lead- and zinc-bearing raw material, wherein there is the vertical smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition-wall with water-cooled copper elements separating the smelting chamber from the gas cooler shaft, the electric furnace separated from the smelting chamber by the partition-wall with water-cooled copper elements, jacketed belt, facilities to tap smelting products and the hearth. Thereby the ratio between levels difference of partitions lower edges and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.15-0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.25-

35 2.10. According to the invention on the gas cooler shaft walls no more than two tuyeres can be installed at a level of the partition lower edge, separating the gas-cooler shaft from the smelting chamber with the a slope to the hearth at an angle to horizontal plane, determined by the following formula
(Formula Removed)
wherein a - tuyeres slope angle;
k - coefficient of tuyeres slope angle, equaled to 1.11 -1.25; AH - difference of partitions lower edges levels; B - inside width of the gas cooler shaft.
It is reasonable as per the invention that while installing two tuyeres they are to be arranged one on each opposite side wall of the gas cooler shaft with mirror-like shift relatively to its axial cross-section of the gas cooler shaft, the ratio of which towards inside length of the gas cooler shaft amounts to 0.25-0.30.
The installation of tuyeres and their arrangement allow to supply oxygen-containing gas onto the surface of carbon material layer, floating on slag melt bath in the bottom area of the gas cooler shaft, where reaction gases from the smelting chamber are supplied. It gives opportunity to afterburn carbon monoxide, contained in reaction gases of the smelting chamber as a result of reduction reactions of oxide melt in the layer of carbon reductant, floating on slag melt bath under the burner flame of the smelting chamber as well as opportunity of incomplete burning of solid carbon fuel in the flame, introduced into the charge at low calorific capacity of the processed raw material. At insignificant amount of carbon monoxide contained in the smelting chamber reaction gases, oxygen introduced through tuyeres together with oxygen-containing gas, is consumed for burning of solid carbon in the layer of carbon material floating on slag melt bath in the bottom area of the gas cooler shaft.
At carbon monoxide burning, contained in the smelting chamber reaction gases or at burning of solid carbon in the layer of carbon material, floating on slag melt bath in the bottom area of the gas cooler shaft, the heat is evolved, the portion of it goes to increase the temperature of slag melt in this dead zone of the unit. The increase of slag melt temperature prevents crusts formation on the bottom part of the gas cooler shaft walls and speeds up circulation of slag melt flow between the electric furnace, the smelting chamber and the gas cooler shaft simultaneously increasing its heat content. It leads towards increase in heat input into the working area of carbon reductant layer under the burner with circulating flow of slag melt and the corresponding speed-up of flame melt reduction. As a result the direct recovery of lead into lead bullion is increased and the possibility of the unit specific capacity improvement is provided.

35 is provided.
The increase of direct recovery of lead into lead bullion and simultaneous increase of the unit specific capacity are provided at the expense of the reduction of dust entrainment and correspondingly the reduction of recycle sulphate dusts content in charge, going to the burner due to tuyeres slope to the unit hearth. Injection of oxygen-containing gas through tuyeres with down-directed flow velocity component into the flow of reaction gases, going out from the smelting chamber causes their slowdown at the entrance of the gas cooler shaft and increases the velocity of dust particles precipitation, carried out by reaction gases from the smelting chamber.
At installation of tuyeres on gas cooler shaft walls at the level lower than the level of the partition lower edge that separates the gas cooler shaft from the smelting chamber the effect of heat release at the surface of slag melt remains. However, the portion of reaction gases begins to go over the flow of oxygen-containing gas injected through tuyeres. It leads to reduction of reaction gases slowdown effect and the decrease in velocity of dust particles precipitation, carried out by reaction gases from the smelting chamber. Moreover, the approaching of oxygen-containing gas jet from tuyeres to the surface of slag bath will result in increase of already settled dust particles carry-over. As a result, smelting dusts output and their portion in charge will increase and the flame temperature, the rate of oxide melt reduction in the layer of carbon reductant, direct lead recovery into lead bullion and the unit specific capacity will reduce.
At installation of tuyeres at the level higher than the level of the partition lower edge the area of heat release moves away from the slag melt surface. Moreover, at insufficient content of carbon monoxide in reaction gases of the smelting chamber the higher level of tuyeres installation leads to reduction of the contact between oxygen-containing gas and the layer of carbon material. It will reduce heat input into slag bath under the gas cooler shaft. As a result, there will be reduced heat content and intensity of slag melt flow circulation between the electric furnace, the smelting chamber and the gas cooler shaft that will lead to slow-up of heat input into the working area of the layer of carbon reductant under the burner. Correspondingly, there will be the decrease in velocity of the flame melt reduction, in direct recovery of lead into lead bullion and in the unit specific capacity.
At the setting of tuyeres slope at an angle to horizontal plane with k coefficient, that is less than 1.11, the area of heat release from afterburning of carbon monoxide in reaction gases of the smelting chamber will move away from the slag melt surface. Moreover, oxygen-containing gas injected through tuyeres during some time of the unit operation time after slag tapping won't be in contact with the layer of carbon material in the gas cooler shaft. As a

35 result, total flow of heat into slag bath under gas cooler shaft will be reduced. It will reduce the effect of the process of crusts formation slowdown on the bottom part of the gas cooler shaft walls as well as the intensity of slag melt flow circulation between the electric furnace, the smelting chamber and the gas cooler shaft and its heat content. Thereby, there will be reduced heat input into the layer of carbon reductant under the flame of the burner and simultaneously the rate of flame melt reduction. As a result, direct lead recovery into lead bullion and the unit specific capacity will be reduced. Additional reduction of the direct lead recovery into lead bullion and the unit specific capacity in this case is stipulated by the velocity reduction of dust particles precipitation, carried out by reaction gases from the smelting chamber. Thereby, there will be the increase of smelting dusts output and their portion in charge and the temperature of flame and the rate of oxide melt reduction in the layer of carbon reductant will be reduced. As a result, there will be a simultaneous decrease in the direct lead recovery into lead bullion and the unit specific capacity.
At the setting of tuyeres slope to the hearth at an angle to horizontal plane with k coefficient, that is more than 1.25, as well as in the case of tuyeres installation at the level lower than the level of the partition lower edge that separates the gas cooler shaft from the smelting chamber, the part of reaction gases will begin to go over the flow of oxygen-containing gas injected through tuyeres. It leads to reduction of reaction gases slowdown effect and the decrease in velocity of dust particles precipitation, carried out from the smelting chamber. Moreover, the increase of tuyeres slope angle to the surface of slag bath will result in blowing-out of the already settled dust particles and in spattering of fine drops of slag melt into the flow of upward reaction gases. As a result, output of smelting dusts and their portion in charge will increase and the flame temperature and the rate of oxide melt reduction in the layer of carbon reductant will decrease. Therefore, direct lead recovery into lead bullion and the unit specific capacity will decrease too.
At installation of two tuyeres, one on each side wall of the gas cooler shaft with mirror-like shift relatively to its axial cross-section, the effect of assigned task achievement is improved. It is determined by the following two factors.
Firstly, the installation of two tuyeres axes of which are mirror-like shifted relatively to its axial cross-section of the gas cooler shaft leads to the increase of surface of heat transfer to slag bath from burning of carbon monoxide reaction gases of smelting chamber or from solid carbon burning in the layer of carbon reductant. Correspondingly, at the same thermal effect from reaction gases afterburning or from burning of solid carbon in the layer of carbon reductant on the surface of slag melt, heat gain to slag bath volume under the gas cooler shaft increases. The increase of heat content of slag melt results in speed-up of its circulation and

35 increase of heat gain into the area of reduction reactions flow. The result is additional increase of direct lead recovery into lead bullion and improvement of the unit specific capacity.
Secondly, the installation of two tuyeres, one on each side wall of gas cooler shaft with mirror-like shift relatively to its axial cross-section leads to additional effect of the increase of direct lead recovery into lead bullion and the unit specific capacity at the expense of dust entrainment and correspondingly, the increase of recycle sulphate dusts content in charge, entering to the burner. The decrease of dust entrainment in this case is stipulated by the injection of oxygen-containing gas through two tuyeres, installed on opposite side walls of the gas cooler shaft and mirror-like shifted relatively to its axial cross-section, and leads to spinning of the gas cooler shaft upward flow of reaction gases going out from smelting chamber. As a result, there is centrifugal component of particles velocity promoting their complete precipitation on gas cooler shaft walls.
The effect of set up task achievement is enhanced at the increase of distance from each tuyere up to the axial cross-section of the gas cooler shaft. It is stipulated by the enlargement of the total heat transfer surface between the area of heat release from reaction gases afterburning or burning of solid carbon and of slag bath. Correspondingly, there is an increase of heat gain into slag bath volume, the increase of its heat content and of slag melt circulation velocity in this area of the unit. It leads to the increase of heat intake to the area of reduction reactions and their speed up. The result of it is increase of direct lead recovery and of specific capacity. Moreover, the increase of the distance between tuyeres axes strengthens the effect of spinning of the gas cooler shaft upward flow of reaction gases that leads to more complete precipitation of dust particles on gas cooler shaft walls.
The strongest effect is achieved at tuyeres axes distance from axial cross-section of the gas cooler shaft the ratio of which to its inside length amounts to 0.25-0.30. At this distance there is achieved the maximum contact surface of heat release area and slag melt bath, as far as flows of burning gases from opposite tuyeres stop to shut. Moreover, at this distance there is achieved the noticeable effect of spinning of reaction gases upward flow and the speed up of precipitation of dust particles on gas cooler shaft walls without overheating of jackets by flows of burning gases from afterburning of carbon monoxide (or burning of solid carbon on the surface of carbon material layer).
At the distance of tuyeres axes from the gas cooler shaft axial cross-section the ratio of which to its inside length is less than 0.25, the heat exchange surface of hot gases and slag bath and the effect of spinning of upward reaction gases are decreased. As a result, there is a simultaneous decrease of heat flow, transferred to the volume of slag melt bath, and of degree of dust particles precipitation on the gas cooler shaft walls. Correspondingly, there is the

35 decrease of effect of additional slag melt heat content increase of the corresponding speed up of its circulation in slag bath as well as of the effect of reduction of recycle sulphate dusts entrainment from the unit. Thus, the blowing through tuyeres does not result in maximum possible enhancement of the effect of the unit specific capacity increase as well as of the direct lead recovery into lead bullion at the expense of heat input increase into the area of reduction reactions flowing with flame melt and melt flow circulating in slag bath, that would provide the speed up of oxide melt reduction in the layer of carbon reductant.
At the distance of tuyeres axes from the gas cooler shaft axial cross-section the ratio of which to the inside length of the gas cooler shaft is more than 0.30, the effect of heat transfer from burning gases into slag melt bath and effect of spinning of upward reaction gases, determining the degree of dusts precipitation on gas cooler shaft walls are not increased. However, high-temperature burning area of carbon monoxide in reaction gases and of solid carbon in carbon layer is approaching to the unit walls noticeably increasing specific heat load on jacketed belt in that local area and increasing thereby the probability of jackets burning-out.
The invention is illustrated by drawings. On Figure 1 there is a unit to process powdered lead- and zinc-bearing raw materials, general view; on Figure 2 and Figure 3 -sections AA and BB of the gas cooler shaft, presented on Figure 1 at installing one tuyere; on Figure 4 - section BB of the gas cooler shaft presented on Figure 1 at installing two tuyeres.
The unit consists of a vertical smelting chamber 1 of rectangular cross-section, in the roof of which the burner 2 for feeding of charge, oxygen, recycle dusts and solid reductant is installed, partitions 3 with water-cooled copper elements, that installed vertically and dividing the smelting chamber 1 from the gas cooler shaft 4 on side wall of which tuyeres 5, 6 for oxygen-containing gas supply are installed, the electric furnace 7, adjacent to the smelting chamber and separated from it by the vertical partition 8 with water-cooled copper elements, total for the smelting chamber, the electric furnace and the hearth gas cooler shaft 9, the jacketed belt 10 and facilities to tap smelting products 11.
The unit operates in the following way.
Powdered charge, composed from lead and lead-zinc raw material (lead, lead-zinc, lead-copper, lead-copper-zinc, lead-silver concentrates, lead dusts, lead-bearing residues, lead bullion refining recycles, battery paste and other secondary lead materials), fluxes and, if necessary, solid carbon fuel (coke, petroleum coke, black, brown or charcoal) after drying to moisture content less than 1% is mixed with crushed carbon reductant (coke, petroleum coke, black or charcoal) and transferred to the burner 2 (see Figure 1) through which by the flow of process oxygen (94-99% O2) is blown into the smelting chamber 1 of the unit. In the smelting chamber 1 under the effect of radiation from flame and high temperatures of upward furnace

35 gases (T=1100-1200°C) charge is ignited, oxidized and smelted in suspended state with production of disperse oxide melt. In bottom part of the smelting chamber 1, flame temperature is achieved 1350-1450°C. The degree of charge desulphurization is controlled by the change of ratio of charge and oxygen consumption in the burner 2.
Crushed carbon reductant transferred together with charge (that is coke, petroleum coke, black or charcoal) with the grain size from 5-20 mm is heated while it is moving to the flame and then it gets onto the surface of slag bath. The presence in the construction the partition 8, arranged downward from the furnace roof and partly submerged into slag melt allows to divide gas space of the smelting chamber 1 and the electric furnace 7 and to form on the surface of slag bath under the burner flame a porous layer of carbon reductant of required height. It provides reduction of non-ferrous metals losses in slag melt at the expense of reduction atmosphere creation in the electric furnace and speed up of small particles of reduced metals precipitation into bottom metallic phase, resulting from their coagulation and coarsening of carbon reductant layer in porous structure.
Disperse oxide melt formed in the process of flash smelting goes onto a porous layer of crushed carbon reductant and leaking through it is undergone selective reduction. Lead oxides are reduced to metallic lead and zinc oxides are remained in slag melt, which together with metallic lead flows under the partition 8 from the smelting chamber 1 into the electric furnace 7 serving for accumulation and settling of smelting products with their separation by specific weight and if necessary - for partial tapping of zinc from slag melt by feeding small-sized carbon reductant on the surface of slag bath of the electric furnace. Copper oxides, similar to lead oxides are reduced in the layer of carbon reductant to metal and transferred to lead bullion, non-ferrous metals sulfides presented in disperse flame melt either divided between metallic or slag phases at charge desulphurization degree more than 90-94% or at less degree of charge desulphurization they form individual matte phase, forming in the process of smelting products settling in the electric furnace. It allows conducting rough decoppering of lead bullion with recovering of copper excess from processed lead- and zinc-bearing raw material to polymetallic matter directly in the unit.
Part of heat energy, released from the electric furnace together with circulating flow of slag melt of total slag bath goes to the smelting chamber and partly soaked by the layer of carbon reductant. Together with heat flow, going with flame melt, heat gain from the electric furnace allows compensate heat consumption by endothermal reactions of oxides reduction in porous carbon layer.
Slag and lead are tapped through the facilities 11 from the electric furnace 7 and then transferred to processing to produce marketable products.

35 Sulfur dioxide reaction gases from the smelting chamber 1, formed during charge flash
smelting go under the partition 3 arranged downward from the furnace roof that doesn't come to the surface of slag melt and then go for cooling into the gas cooler shaft 4.
In the bottom part of the gas cooler shaft 4 reaction gases, containing carbon monoxide, are afterburnt at the expense of oxygen-containing gas supply through tuyeres 5, 6. Part of heat energy, released hereby is absorbed by flow of slag melt circulating in the total unit slag bath and goes to the smelting chamber into the layer of carbon reductant adding the heat flow going with flame melt and slag melt from the electric furnace. It enhances possibility to compensate heat consumption by endothermal reactions of oxides reduction in porous carbon layer. Reaction gases depleted by carbon monoxide go upward to the gas cooler shaft outlet and are cooled at the expense of heat exchange with water-cooled surfaces of shaft walls.
After the gas cooler 4 gases are purified in the electrostatic precipitator (it is not shown on drawings) and then go for sulphur utilization with production of marketable products (sulphuric acid, elemental sulphur, sulphuric anhydride or salts). Dust, captured by the electrostatic precipitator, is continuously returned for smelting.
The invention is illustrated by the unit operation examples.
Example 1 (by prototype). In the pilot unit of KIVCET (the smelting chamber cross-sectional area - 1.4 m2, the smelting chamber height - 3.3 m, the gas cooler shaft cross-sectional area - 1.44 m2, the electric furnace hearth area - 5 m2, generating capacity of the electric furnace transformer - 1200 kW) having difference ratio between partitions lower edges levels and the distance from smelting chamber roof to partition lower edge, separating the electric furnace from the smelting chamber, that equaled 0.28 and ratio between distance from partition lower edge, separating the electric furnace from the smelting chamber up to the hearth and the difference of partitions lower edges levels, equaled 1.25 there was conducted processing of charge, prepared from sulphide lead concentrates, lead dusts, lead-bearing residues of zinc production, battery paste, quartz and lime fluxes of the following composition, %: 34.0 of lead, 9.6 of zinc, 1.1 of copper, 12.3 of iron, 10.2 of sulphur, 8.4 of silicon dioxide,
4.1 of calcium oxide. To compensate low calorific capacity of charge there was introduce into
it powdered coal of the composition, %: 42.5 of solid carbon, 28.0 of volatiles and 30.0 of ash,
containing, %: 9.0 of iron, 55.8 of silicon dioxide and 4.5 of calcium oxide.
As a reductant there was used coke breeze, containing %: 85.5 of carbon, 1.3 of iron,
7.2 of silicon dioxide, 1.3 of calcium oxide. In the course of tests there was processed 50 t of
charge. Obtained results of the unit operation are given in Table 1 - Comparison of prototype
operation figures and proposed unit with one tuyere.

35 Example 2. Tests were conducted in modernized in accordance with the declared
invention (claim 1) pilot unit of KIVCET that had parameters and conditions as in Example 1. Thereby the tuyere was installed on side wall of the gas cooler in flat surface of its axial cross-section at the level of partition lower edge, separating the gas cooler shaft from the smelting chamber, with a slope to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.2. Totally there was processed 48 t of charge.
Example 3. Tests were conducted under similar conditions as in Example 2, but tuyere was shifted downward from the partition lower edge level, separating the gas cooler shaft from the smelting chamber at the distance of Ah, ratio of which to difference of partitions lower edges levels AH amounted to 0.2.
Example 4. Tests were conducted under similar conditions as in Example 2, but the tuyere was shifted upward from the partition lower edge level, separating the gas cooler shaft from the smelting chamber at the distance of Ah, ratio of which to difference of partitions lower edges levels AH amounted to 0.2
Example 5. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.11.
Example 6. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.25.
Example 7. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.00.
Example 8. Tests were conducted under similar conditions as in Example 2, but the tuyere was inclined to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.30.
Example 9. Tests were conducted under similar conditions as in Example 2, but the tuyere was installed on end wall of the gas cooler shaft in flat surface of its longitudinal axial section with a slope to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.20.
Tests results by Examples 1 -9 are given in Table 1.
Example 10. Tests were conducted under similar conditions as in Example 2, but two tuyeres were installed to supply oxygen-containing gas, one each opposite side wall of the gas cooler. Tuyeres were installed in one flat surface of axial cross-section of gas cooler shaft on the level of partition lower edge, separating the gas cooler shaft from the smelting chamber

the level of partition lower edge, separating the gas cooler shaft from the smelting chamber with a slope to the hearth at an angle to horizontal plane, determined by k coefficient, equaled 1.20.
Example 11. Tests were conducted under similar conditions as in Example 2, but two tuyeres were installed as in Example 10, the difference was that one of tuyeres was shifted from axial cross-section plane of the gas cooler shaft at the distance of Al, the ratio of which to shaft inside length L amounted to 0.27.
Example 12. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length -∆l/L amounted to 0.20.
Example 13. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length - ∆l/L amounted to 0.25.
Example 14. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length - ∆l/L amounted to 0.27.
Example 15. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of the gas cooler shaft at the distance, the ratio of which to its inside length - Al/L amounted to 0.30.
Example 16. Tests were conducted under similar conditions as in Example 2, two tuyeres were installed as in Example 10, the difference was that each of two opposite tuyeres was shifted from axial cross-section of gas cooler shaft at the distance, the ratio of which to its inside length - ∆l/L amounted to 0.35.
The unit operation figues of Examples 10-16 are given in Table 2 (Comparison of operation figures of proposed unit with one and two tuyeres) in comparison with figures of Example 2 of Table 1.
As it is seen from data comparison of Examples 1 and 2-9 in Table 1, proposed unit in comparison with prototype allows increase of lead direct recovery into lead bullion by 3.03-3.06 relative % and increase of the unit specific capacity by 0.4-0.6 relative %. It is shown that the use of the proposed level of tuyeres installation and slope angle range to the hearth provides achievement of higher figures of lead direct recovery into lead bullion and of the unit

35 provides achievement of higher figures of lead direct recovery into lead bullion and of the unit specific capacity (compare Examples 2, 5 and 6 with Examples 3, 4, 7 and 8).
It is shown also that choice of the gas cooler shaft wall at installation of one tuyere to supply oxygen-containing gas practically does not influence the unit operation figures (compare Examples 2 and 9).
Installation of two tuyeres, one on each opposite side wall of gas cooler shaft does not improve the unit operation figures in comparison with the variant of one tuyere installation in case if each of these tuyeres is situated in one and the same cross-section of the gas cooler shaft (compare Examples 2 and 10 of Table 2).
The shift of tuyeres axes that is not mirror-like relative to axial cross-section of the gas > cooler shaft gives improvement of the unit operation figures but does not provide the achievement of maximum possible additional effect in solution of assigned task (compare Examples 2 and 11 with Examples 13-15 in Table 2). Mirror-like tuyeres shift relatively to axial cross-section of the gas cooler shaft with the use of proposed range of distance ratios from tuyeres axes up to axial cross-section of gas cooler shaft to its inside length (0.25-0.30) gives additional increase of lead direct recovery by 0.13 relative % and increase of the unit specific capacity by 0.33 relative % relatively to the variant of one tuyere use (compare Examples 12 and 13-15). The reduction of this ratio of less proposed range of 0.25 reduces lead direct recovery and the unit specific capacity approaching these figures to the variant of the unit operation with one tuyere (compare Examples 12 and 2). The increase of this ratio of more proposed range of 0.30 does not result in further improvement of the unit operation figures (compare Examples 15-16), but noticeably increases possibility of thermal damage of jackets at the expense of high-temperature area of smelting camber reaction gases afterburning approaching to them.
Moreover, as is seen from Tables 1 and 2, the present invention allows to reduce specific expenses on electric power by 6.2-6.8 relative % and to increase the unit useful time by 3-5% at the expense of heating-up of slag bath area under the gas cooler shaft, that provides slowdown of the process of crusts formation in this unit area.
The unit to process powdered lead- and zinc-bearing raw materials includes the vertical smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition wall with water cooled copper elements separating smelting chamber from the gas cooler shaft, the electric furnace separated from the smelting chamber by the partition with water cooled copper elements, the jacketed belt, facilities to tap smelting products, the hearth, herewith, ratio difference between the partition lower edges levels and the distance from the smelting chamber roof to the partition lower edge, separating the electric furnace from the smelting chamber amounts to

0.15-0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the difference of lower edges levels of partitions amounts to 1.25-2.10 differing by fact that on the gas cooler shaft walls there are no more than two tuyeres installed that are on the level of partition lower edge, separating the electric furnace from the smelting chamber with a slope to the hearth at an angle to horizontal plane, determined by the following formula: a = arctg (k-∆H/B), wherein - ά - tuyeres slope angle; k - coefficient of tuyeres slope angle, equaled to 1.11-1.25; ∆H - difference of partition lower edges levels; B - inside width of gas cooler shaft.
Table 1. Comparison of prototype operation figures and proposed unit with one tuyere.
(Table Removed)

Table 2. Comparison of operation figures of proposed unit with one and two tuyeres

(Table Removed)

We claim:-
1. The unit to process powdered lead- and zinc-bearing raw materials includes the vertical
smelting chamber of rectangular cross-section with the burner, the gas cooler shaft, the partition wall
with water cooled copper elements separating smelting chamber from the gas cooler shaft, the
electric furnace separated from the smelting chamber by the partition with water cooled copper
elements, the jacketed belt, facilities to tap smelting products, the hearth, herewith, ratio difference
between the partition lower edges levels and the distance from the smelting chamber roof to the
partition lower edge, separating the electric furnace from the smelting chamber amounts to 0.15-
0.29 and the ratio between the distance from the lower edge of this partition to the hearth and the
difference of lower edges levels of partitions amounts to 1.25-2.10 differing by fact that on the
gas cooler shaft walls there are no more than two tuyeres installed that are on the level of partition
lower edge, separating the electric furnace from the smelting chamber with a slope to the hearth
at an angle to horizontal plane, determined by the following formula
(Formula Removed)
wherein - a - tuyeres slope angle;
k - coefficient of tuyeres slope angle, equaled to 1.11-1.25; ∆H-difference of partition lower edges levels; B - inside width of gas cooler shaft.
2. The unit to process powdered lead- and zinc-bearing raw materials by claim 1 differs by
the fact'that at installation of two tuyeres they are arranged by one on each opposite side wall of
the gas cooler shaft with mirror-like shift relative to its axial cross-section.
3. The unit to process powdered lead- and zinc-bearing raw materials by claims 1, 2,
differs by fact that at installation of two tuyeres each of them is arranged at the distance from
axial cross-section of gas cooler shaft, the ratio of which to inside length of the gas cooler shaft
amounts to 0.25-0.30.
4. Unit to process powdered lead- and zinc-bearing raw materials as claimed in any of
the above claims substantially as described in the specification and illustrated in the
accompanying drawings.

Documents:

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Patent Number

269391

Indian Patent Application Number

5775/DELNP/2007

PG Journal Number

44/2015

Publication Date

30-Oct-2015

Grant Date

19-Oct-2015

Date of Filing

25-Jul-2007

Name of Patentee

SA "VNIITSVETMET"

Applicant Address

1,PROMYSHLENNAYA ST., UST-KAMENOGORSK, 070002 KAZAKHSTAN REPUBLIC

Inventors:

#	Inventor's Name	Inventor's Address
1	SHUMSKIY VIKTOR ALEXANDROVICH	SOLNECHNAYA ST. 6/1,APT. 24, UST-KAMENOGORSK,070015,KAZAKHSTAN
2	USHAKOV NIKOLAY NIKOLAYEVICH	VIROSHILOV ST. 167, APT. 7, UST-KAMENOGORSK, 070018, KAZAKHSTAN
3	STARTSEV IGOR VLADIMIROVICH	USHANOV ST. 72, APT. 53, UST-KAMENOGORSK, 070019, KAZAKHSTAN
4	POLYAKOV IVAN PETROVICH	LENIN AVE. 58/1, APT. 12 UST. KAMENOGORSK, 070018, KAZAKHSTAN
5	RAGULIN BORIS ALEXANDROVICH	POBEDY AVE. 11, APT. 46, UST-KAMENOGORSK, 070004, KAZAKHSTAN
6	CHALENKO VALENTINA VASILYEVNA	UTEPOV ST. 7, APT.25 UST- KAMENOGORSK, 070016, KAZAKHSTAN

PCT International Classification Number

C22B7/00

PCT International Application Number

PCT/KZ2006/000015

PCT International Filing date

2006-11-28

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	2006/0853.1	2006-07-24	Kazakhstan