FI56397C - OIL ANALYZING FOR SUSPENSIONSSMAELTNING AV FINFOERDELADE SULFID- OCH / ELLER OXIDMALMER ELLER -KONCENTRAT - Google Patents

Description

ΠΓ5ϊ ^ η ra1 ANNOUNCEMENT CCOQ7 4s3fjB ™ (11 * UTLÄGGN I NGSSKRIFT ** 'C ^ 45j Patent granted-tty 10 OI 1930 ^ ¾¾ Patent seidelit V * (51) Kv.lk. * / Lnt.ci. * c 22 B 5/00 FINLAND —FINLAND (21) P * t * nttlh »k« mu * - Ptttntan «6knln | 2088/7 ^ (22) Htk« mUptlvi - Ansttknlngtdtg 05.07.7 ^

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(41) Become public - Bllvlt offantllf 06.01.76 FMOTttl- 1 · r.klrtwlh> niOi> (u fm.Mk.lp ™. |. KppLMku ™ p ™ .-

Patent- och registerstyrelsen 'Aniökin utltgd oeh utl. «Krtft * n publtnrad 28.09.79 (32) (33) (31) Requested« t determined * —Baglrd prlorltat (71) Outokumpu Oy, Outokumpu, Suomi-Finland (Fl) (72 ) Olavi August Aaltonen, Pori, Jyrki Tapani Juusela, Pori, Finland-Finland (Fl) (7U) Berggren Oy Ab (5U) Method and apparatus for suspension smelting of finely divided sulphide and / or oxide ores or concentrates - Förfarande och anordning för suspensionssmaltning av finfördel This invention relates to a method and apparatus for suspending finely divided sulphide or oxide and sulphide ores and concentrates.

Suspension smelting of sulphide concentrates, which is based on the Finnish patent 22 69U, has become increasingly used in various parts of the world. It is known to be an economically advantageous and, in addition, environmentally friendly smelting method. This so-called however, nowhere is the autogenous flame smelting process completely autogenous, operating without external fuel, but the flame smelting furnace must use different amounts of fuel, usually oil, in different places. The flame smelting method is well known and described in many articles (e.g. Journal of Metals,

June 1958, Petri Bryk, Jöhn Ryselin, Jorma Honkasalo and Rolf Malmström: "Plash Smelting Copper Concentrates" and "The First International Flash Smelting Congress, Finland, October 23-27, 1972").

C 22 B 15/00 2 56397

Briefly, the method is as follows. The dried fines and the circulating air dust and possibly slag-forming substances and the air and / or oxygen mixture, preheated or cold, are introduced into a vertical flame melting furnace reaction shaft from top to bottom, where the oxidation reactions take place in suspension at high temperature. Under the influence of the heat of reaction and possible additional fuel, most of the reaction products melt (with the exception of some slag components). In the case of copper concentrate, the following total reactions can be considered to take place in the reaction pit:

2 Cu PeS2 Cu2S + 1/2 S2 + 2 PeS

Cu 2 S + 1 1/2 O 2 - * - Cu 2 O + SO 2

PeS2 -> FeS + 1/2 S2 1/2 S2 ♦ O, - S02

PeS + 1 1/2 02 -> FeO + SO2 3 PeO + 1/2 02 - * Fe3Oi |

Other concentrates undergo similar reactions. The suspension falling from the reaction shaft enters the horizontal furnace part of the so-called to a lower furnace, i.e. a settler, with at least two but sometimes three different layers of melt. The bottom can be a metal layer, most usually a blister cup, with either a stone layer on top or a slag layer directly on top. Most often, the bottom is a layer of stone and the top is a layer of slag. Most of the molten or solid particles in the suspension fall directly into the melt below the reaction shaft at approximately the slag settling temperature, with the finest part continuing with the gases to the other end of the furnace. Along the way, the suspension settles into the lower furnace all the time. At its other end, the gases are led directly up to the so-called along the riser, from where on to gas treatment equipment, waste boiler and electrostatic precipitator. Defrosting is usually performed as autogenously as possible, without external fuel. This is treated in the reaction shaft by preheating the air and / or enriching it with oxygen.

With conventional sulfide concentrates containing chalcopyrite, pentlandites, pyrites and other iron sulfides, it has been found that oxidation of iron in the reaction shaft does not lead to the formation of the desired FeO, but is up to the degree of Pe 2 O 2.

The higher the aim of stone melting, i.e. the further 3 56397 concentrate in the reaction shaft in question. temperatures are oxidized, the more completely the oxidized iron appears at the bottom of the reaction shaft as a magnetite, Fe 2 O 2. Oxides of other metals may also be formed. In any case, an equivalent amount of ferrous sulfide FeS or other metal sulfides remains unoxidized. The final reactions take place almost exclusively after the particles have fallen into the melt of the lower furnace and the desired rock and / or metal and slag phases are formed. The following reactions are possible:

Ia 3Fe3% s) + FeS (2) 10Fe0 (s) + SO2 (g) ΔΗ ° 1300ο Ξ + 398 kJ

Ib ^ Pe30U (1) + FeS (a) 10 Fe0 (s) + SO2 (g) ΔΗ 1300 ° = 16 kJ

II 2Pe0 (s) + SiO2 (g) 2Fe0 'SiO2 (2) ΔΗ ° 1300 °' + 73.5 ^

III Cu2S (2) + 2Cu20 (2) 6Cu (2) + SC> 2 (g) ΔΗ ° ΐ300 ° '+ 76.2 kJ

IV 3Cu2 ° (2) + FeS (2) 6Cu (2) + Fe0 (s) + SO2 (g)

ΔΗ 1300 ° = - 35 kJ

V Cu2 ° (2) + FeS (2) Fe0 (s) + Cu2S (2) ΔΗ 1300 ° = "115 kJ

la + H ^ Pe3 ^ 4 (s) + Fe ^ (2) + 3 ^ ^ 2 (s) 5 (2FeO * ^ - ^ - ^ 2 ^ (2) + ^ 2 (g)

Λ ° 1300 ° + 766 kJ

Ib + II (i) + FeS ^ 2 ^ + 5SiO2 ^ ^ 5 (2FeO · SiO2 ^ 2 ^ ^ ^ 2 (g)

ΔΗ ° 1300 ° "+ 352 kJ

In normal copper smelting, the most significant in terms of temperature economy is the combination of magnetite reduction and slag formation reactions (Ia + II or Ib + II). Significant amounts of copper oxide Cu 2 O begin to appear at the bottom of the reaction shaft only when aiming for a rock or metallic copper containing more than 75% Cu. Even then, however, the magnetite must be reduced low enough so that the copper losses to the slag are not unreasonably large, so that the reaction I + II is always significant. Other reactions occur to a small extent, but are not very effective in terms of heat economy. In addition to these endothermic reactions, there are also heat losses in the lower furnace.

According to current practice, oil, gas or coal are burned both under the reaction shaft and along the bottom furnace to treat sub-furnace reactions and to compensate for heat losses. Under the reaction shaft where the endothermic reactions take place, the melt mixes well due to the SO 2 gas evolved and the heat transfer is efficient, but elsewhere in the furnace where the slag is almost stationary, the heat transfer is poor. Measurements have shown that the temperature difference in such standing slag is 5-10 ° C / cm. If the lowering temperature of the slag is 1250-1300 ° C, its surface temperature 5 6 3 ϋ 7 can easily be higher than 100 ° C. Heat transfer from the combustion gases through the slag is difficult due to the high surface temperature of the slag and the back radiation. The entire amount of gas has to be heated to a high temperature and the heat losses in the part above the furnace melt become large. Thus, the amount of gas increases and expensive gas treatment equipment, waste heat boiler, electric filter, fans, etc. have to be dimensioned accordingly.

The object of the present invention is to obviate the above-mentioned drawbacks and to provide a method and an apparatus for suspending finely divided sulphide or oxide and sulphide ores and concentrates, the suspension of fines in air and / or oxygen being passed from top to bottom in a reaction zone formed jointly by the suspension and the melt below. to oxidize and partially melt the raw material in the suspension, after which the suspension stream is caused to change its direction perpendicular to the sides so that most of the raw material components in the suspension stream collide with the surface of the accumulated melt , cooling and separating from the residual suspension stream solids which are optionally returned to the reaction zone.

The main features of the invention appear from the appended claim 1.

According to the invention, the disadvantages of the present practice described above can be reduced in two ways. The reaction shaft is shortened or initially made so short that the highest temperature and reaction rate in the reaction shaft and its extension of the lower furnace is reached just before the suspension is separated from the gases into the melt. In this case, savings in investment costs are achieved when the reaction gap can be made much lower than at present. In flame smelters, the height of the reaction shaft and the heavy silo structures built on top of the shaft determine the entire height of the smelter and thus have a significant impact on investment and also operating costs (material transfers up to the silos). Heat losses also decrease as the reaction gap is shortened. This is especially the case in cases where the concentrate has a low calorific value and additional fuel has to be used in the reaction shaft.

An alternative way is to arrange the feed material of the raw material so that the distance of the feed point from the surface of the melt can be adjusted to the desired size without having to change the length of the reaction shaft.

The invention will be described in more detail below with reference to the accompanying drawings, in which Figure 1 is a cross-sectional side view of a test flame melting furnace, Figures 2-4 show oxygen distribution in the reaction shaft, Figure 5 as a function of sulfur pressure.

The amount of heat required for the endothermic reactions of the process is higher the richer the stone is sought. The experiments below should give a picture of this. They have been calculated in a test furnace, Figure 1 (1-2 t concentrate / h) based on the results obtained. There has been no recovery of air dust in the tests, but the amounts of slag and rock have been calculated on the basis of the analyzes received as if there had been a complete recycling of air dust. However, this does not materially affect the outcome of the reviews.

6 56397

Kuparirikasteanalyysi:

Cu 19.0%

Pe 38.5% S 34.5%

Si02 4.0% 3+ ·

Oxygen has been analyzed from the rock and Fe from the slag, from which the Fe 2 O 2 concentrations have been calculated. The amount of stone and iron left in the slag has been calculated from the sulfur and copper. By subtracting the iron present as a magnetite from the total iron of the slag and further the iron in it as a rock, the amount of FeO formed according to reaction I is obtained. The melting heat of magnetite is 138 kJ / mol. All values are calculated per ton of concentrate.

Koe I

Stone 327 kg Slag 683 kg

Cu 55.0% Cu 1.5%

Fe 20.0% Fe 46.8% S 21.9% S 1.6% O 2.1% Fe2 ° k 13.5%

SiO2 31.5%

Amount of magnetite: in the stone 25 kg in slag 92 "117 kg

The slag Fe2 + according to reaction II 253 kg, which according to reaction Ia + II requires heat 345 x lo3 kJ and according to Ib + II 159 x 10 kJ · The "dissolution" of magnetite requires heat 69 x 103 kJ.

Total heat demand 4l4 x lo3 kJ if Fe ^ O ^^ - ^ 9 x 103 kJ if Fe301 ((1) i

Test 2

Stone 240 kg Slag 803 kg

Cu 73.3% Cu 1.8%

Fe 5.4? Pe $ 46.3 S 20.5% S $ 0.4 O 0.45? Fe3 ° 4 20) 5 *

SiO2 31.0%

Amount of magnetite: in stone 4 kg in slag 165 kg 169 kg 2 + 1 5 6 3% 7

The slag-formed Pe according to reaction II is 252 kg, which according to reaction Ia + II requires a heat of 345 x 10 ^ kJ and according to lb + II 159 x 10 ^ kJ. Dissolution of magnetite requires heat of 100 x 10 ^ kJ.

3. 3 Total heat demand 445 x 10 kJ if Fe ^ O ^^ or 159 x 10 kJ if Fe304 (1)>

Actual heat demand is likely to be within the above limits.

The results obtained are by no means absolute. It is not known exactly what reactions and how they actually occur in the reaction gap. However, it is known that the lower the Cu rock, the more it is able to dissolve oxidized iron at a given temperature.

When aiming for a shallow rock, the heat demand approaches a minimum of 159 x 10 ^ kJ. When aiming for a high rock, only part of the oxidized iron can dissolve in the rock droplets, the rest being a solid magnetite. The heat demand then approaches its maximum. The analysis results are obtained from chilled samples. Chilled samples from the suspension falling in the reaction shaft have also been taken from different heights and analyzed, as well as gas analyzes and temperature measurements. From these microscopic samples it has been found that the oxidized iron has been practically a magnetite in the reaction shaft and the slag formation reactions (MeO + SiOg) have not yet begun, but SiO 2 has generally been unreacted. In the test smelters, the concentrate has been 0.1% E 2 O dried and has no granules larger than 2 mm. Figures 2, 3 and 4 show the oxygen distributions in the reaction shaft under different melting conditions. The 0 ^ and SC ^ concentrations are gas chromatographic analyzes and O. (Pe 0) has been calculated as the difference between the solid (molten) bound (- xy) and it is clear from the figures that in this test furnace with a reaction distance of less than 2 m, regardless of the conditions , gas velocity, feed rate, oxygen enrichment, and process air preheating degree, an almost constant level of reaction result is achieved.

Figure 5 shows the corresponding so-called solids calculated from the solid analyzes of the reaction shaft. copper rock concentrations and final concentrations.

From this, it is noted that under the experimental conditions, the reaction shaft reactions resulted in about 40% Cu rock, the final about 60% Cu rock was reached in the lower furnace. It should be noted here that the dots in Figure 5 have been calculated to contain only Cu „S + FeS, .... ... x and no magnetite dissolved at all. In reality, for example, about 40% Cu rock also contains about 5% oxygen, so that in reality the stone contents would be considerably less than 40% Cu. Figure 6 shows the temperatures measured at different heights from the reaction shaft with thermocouples. These measurement results are in good agreement with the analysis results of Figures 2, 3 and 4, confirming the finding that the majority of the reactions in the reaction process have already been completed in a distance of about 2 m. A theoretical analysis of heat transfer and reaction rate in the reaction shaft has led to the conclusion that the reaction rate in the shaft is determined solely by the heating rate of the particle and that in this sub-process the rate difference between particle and gas is of considerable importance. After the ignition of the concentrate, the proportion of reaction temperatures is decisive for the behavior of the whole suspension. Under the reaction shaft conditions, the warming time of the dry concentrate particle to the ignition temperature is of the order of 0.1 s, i.e. the ignition takes place immediately below the vault of the reaction shaft. When the average concentrate particle is taken as 0 = 37 μm, according to the calculation method based on gas diffusion, 67% of its sulfur is burned in -4 to 10 seconds. Endothermic reactions and events such as decomposition of sulfates and carbonates, distillation of pyritic sulfur, evaporation of moisture and micropelletization, etc. slow down both heating and combustion reactions. Poor digestion of the concentrate, go to bed, also results in a considerable average slowing of the reactions. For example, pyrite can then be found at the bottom of the reaction shaft and the concentrate can also form a pile in the bottom furnace. Normally, when there is a dry finely divided concentrate, good decomposition, most of the exothermic reactions occur immediately at the top of the reaction pit and endothermic in the melt below the reaction pit. Samples taken from the slag of the flame melting furnace immediately after the reaction shaft (a) and from the other end of the furnace from the slag drop (b) confirm this notion that most of the sub-furnace reactions have taken place immediately below the reaction shaft and only dust deposition and rock and metal deposition in the sub-furnace part of it.

Cu% Pe% S% Pe3 ° i | % Si ° 2% a) 2.6 '43.3 0.5 17.5 31.5 b) 2.4 43.5 0.3 16.5 30.5 c) 18.6 33.0 8, 4 25.7 26.1 c) = corresponding shaft sample before the lower furnace.

When the concentrate has sufficient heat of refraction and the reaction gap is shortened, the temperature of the suspension increases by an amount corresponding to the reduction of heat losses. This is another very significant advantage of the invention. which is used to advantage. This increase in the temperature of the suspension, 9 56397, the change in its enthalpy, is exploited in endothermic reactions in the lower furnace. Thus, the excess heat provided by exothermic oxidation reactions in the reaction shaft is effectively utilized in the endothermic reduction and slag formation reactions of the lower furnace. Efficiency can be understood as meaning that the particles, which must react endothermically with each other in the lower furnace, already contain the required amount of heat, which, as at present, does not have to be given by burning some fuel under or near the reaction shaft.

The invention is described in more detail below by means of examples.

Consider an industrial-scale flame melting furnace with an inner shaft diameter of 4.2 m and a height of 7.5 m. In the lower furnace, the reaction distance to the melt is about 2 m. The measured heat loss of the reaction shaft is 5430 x 103 kJ / h ± 15%.

Feed approx. 30 t / h plus 10% circulating air dust.

Preheating of process air approx. 200 ° C and oxygen enrichment 32% 02.

The reaction gap was autogenous, no additional fuel and the temperature of the suspension falling into the bottom furnace was about 1300 ° C.

Under the reaction shaft, oil was burned at 200 kg / h and elsewhere in the furnace n.

250 kg / h, lower calorific value 13.6 · 103 kJ (removal 1400 ° C). The average settling temperature of the slag was about 128 ° C for oil and about 1180 ° C for the stone. The temperature of the exhaust gases from the lower furnace was about 1400 ° C or more.

Copper concentrate mixture Air dust supply

Analysis: Analysis:

Cu 18.3% Cu 25.10%

Fe 28.5% Fe 24.30% 3 26.7% S 7.30%

Zn 1.9% Zn 5.50%

SiC> 2 16.8% Pb 1.70% change 7.8% SiC> 2 3.70% 100.0% oxygen + other 32.40% 100.0 t 10 56397

Stone 255 kg / t concentrate: Slag 620 kg / t concentrate:

Analysis: Analysis:

Cu 70.0% Cu 1.9%

Fe 8.3% Fe 42.6% s 21.2% S 0.5% O 0.46% Zn 26.9%

Fe ^ Ojj 15.8%

MgO + CaO 1.9% Al 2 O 5 2.0%

Material balance of the reaction shaft per 1 tonne of concentrate:

In:

Concentrate 1000 kg

Air dust 100 "

Oxygen 208 m ^ n 297 "

Nitrogen 442 "553» 1950 kg

Out:

900 kg of molten solid suspension

Air dust oxides 8l "

Nitrogen 442 m ^ n 553 "

Sulfur oxide 144 m ^ n 412 n

Oxygen 3 m ^ n 4 "1950 kg

Example 1

Increasing the temperature of the shaft product replaces the oil used in the lower furnace with 450 kg / h. The useful heat obtained from it is about 210 x 10 ^ kJ / h, tr ^ k, when the exhaust gases of the lower furnace are 1400 C. When the rock fall is taken from one end of the lower furnace and not below the reaction shaft, the temperature of the lower furnace exhaust gases can be allowed to the heat demand is reduced to about 157 x 10 ^ kJ / h, trick.

Change in the heat content of shaft products between 1300-144 ° C.

Melt + solid suspension 0.8 · 10 ^ kJ / ° C, t enriched.

(Pe3 ° 4 (D)

Process gases 1> 0 · 10 ^ kJ / - ”

Flight dust 0.06- 10 ^ kJ / - 11 -

Total 1.9 * 105 kJ / ° C, t enriched.

11 563 * 7

The temperature of the shaft product must be raised by 157 x ίο3 kj / h, trik- = ^ ι, 9 x 103 kJ / ° c, trik <This means that the reaction gap is shortened from the current 7> 5 m to about 1-1.5 m. In this case, the amount of gas leaving the flame furnace also decreases by 3 approx. 5100 m n / h, which is approx. 22%. This released gas volume can be used to increase the capacity according to the following example.

Example 2

Capacity increase approx. 29% · The furnace according to Example I and the same oxygen enrichment 32% 0p are used. the gas volume 5100 nrn / h released from the oil combustion is used in the reaction shaft to oxidize the additional concentrate. This means an increase of about 8.7 tp ^ k / h, i.e. about 29%, and an increase in the temperature of the shaft product of about 30-40 ° C from the value of Example 1. The amount of gas and the gas treatment equipment remain the same.

Example 3

Reducing investment costs. A new plant will be built with the feed and oxygen enrichment values of the old plant. Due to the shortening of the reaction shaft according to the invention, the smelter building will be about 6 m lower and the gas treatment equipment about 27% smaller. This means not only a significant reduction in investment costs but also a reduction in operating costs, as the feed material of the flame furnace does not have to be raised as high as in the old plant and smaller gas treatment equipment of course also means lower operating costs. Also, a short reaction gap requires only a fraction of a refractory lining material compared to a long gap according to current practice.

Example 4

Vigorously increasing the capacity by allowing the temperature of the reaction shaft product to rise above normal. The reaction shaft is shortened from the old one as in Example 1 or a new plant of equivalent height is built. While keeping the amount of gas the same, it is necessary to increase the capacity of the process without increasing the oxygen enrichment. In Example 2, a capacity of 38.7 t / h / h / h was reached with 32% oxygen enrichment. When the oxygen concentration is raised to 50 #, the feed capacity increases to 65 / h, i.e. a good 67%. If the cooling in the reaction shaft and in the front of the lower furnace is not intensified, the temperatures of the shaft product will rise from 12 to 300397 about 300 ~ ^ 00 ° C. In practice, an increase in the temperature of shaft products and sub-furnace melts also increases heat loss. However, in the case of such large temperature rises, special attention must be paid to improving cooling efficiency. This efficient cooling can be carried out in a known manner, e.g. by forced-circulation pressurized water cooling, in which case a large part of the heat losses can be recovered as steam. Apart from the capacity advantage, another considerable advantage of the high reaction temperature of this Example IV is obtained. As the temperature rises, the tendency of iron to oxidize to magnetite decreases sharply. This is evident from Figure 7, which shows equilibrium plots of iron and copper compounds at different temperatures. Values are partially extrapolated from lower temperatures. It is observed that as the temperature rises, the oxygen pressures corresponding to the equilibrium FeO / Fe 2 O 2 also increase. Thus e.g.

temp. 1300 ° C; pn = 10 ~ 7.6 atm u2 1500 ° C; pn = 10 ~ 5.3 atm u2 1700 ° C; pn = 10 “3.2 atm u2

Similarly, raising the temperature promotes the formation of metallic copper according to the equilibrium circuit Cu / C ^ O. Thus, it is possible to more easily make ferrous copper concentrates directly from metallic copper in a flame melting furnace already in the reaction shaft. The crude reaction temperature can still be used for the so-called when thawing mixed concentrates. These mixed concentrates often contain, in addition to the copper concentrate, considerable amounts of e.g. zinc, lead, etc. compounds which could not be separated by conventional e.g. flotation means. They are difficult to use effectively in any current process. However, the high-temperature suspension melting mentioned in this example provides good opportunities to process these so-called concentrate of. It is known that the vapor pressures of these impurity substances such as zinc, lead, arsenic, antimony, bismuth, etc. increase sharply with temperature, so that their enrichment at high temperature from the actual basic concentrate to air dust is possible. These valuable substances, which have occurred as impurities, can thus be processed separately in known ways, and the actual base concentrate, most usually copper concentrate, can be processed into first-class metal.

Of course, more examples of the advantages and possibilities of using the invention could be made, but these already shed sufficient light on the matter. The advantages and possibilities of the invention are summarized as follows.

-Saves energy because the thermal energy contained in the concentrate is given as efficiently as possible to the process itself.

-Reduces the investment and operating costs of the smelters, as the reaction gap and the entire smelter are made significantly lower compared to the current practice.

-Because no fuel is needed in the sub-furnace, gas volumes and gas treatment equipment are kept to a minimum, which has the effect of reducing both investment and operating costs.

-The capacity of the old plant can be significantly increased because no oil is burned in the sub-furnace.

-Enables even better e.g. direct copper production in the flame furnace also from normal, chalky pyrite copper concentrates.

-Allows better so-called. the use of mixed concentrates for the production of copper, since the components volatile at the high reaction temperature can be separately enriched in air dust.

-When using high temperatures, the increased heat losses necessary for the durability of the equipment can be recovered as steam *

Claims (6)

A method for melting a suspension of finely divided sulfide or oxide and sulfide ores and concentrates, wherein the suspension of finely divided feedstock in air and / or acid is passed in a reaction zone formed jointly by the suspension and the underlying melt to oxidize the feedstock in the suspension from top to bottom. and partial melting, after which the slurry stream is caused to change direction perpendicular to the side so that most of the raw material contained in the slurry stream collides with the accumulated molten surface at the bottom of the slurry reaction zone. reaction zone, characterized in that in order to improve the energy economy and increase the capacity of the slurry smelter, the feed of the raw material and / or without the preheating rate and / or ha depending on the feedstock feed or the addition of fuel in the suspension reaction zone to adjust the temperature of the particles falling from top to bottom so that the heat content of the particles impinging on the melt covers the heat required by endothermic reactions in the melt, including possible heat losses. A method according to claim 1, characterized in that the desired heat content of the particles impinging on the melt is obtained by feeding a suspension containing finely divided raw material to the suspension reaction zone from a point arranged at a height of about 2-6 meters from the surface of the melt. Method according to Claim 1 or 2, characterized in that the desired heat content of the particles impinging on the melt is generated by adjusting the flow rate of the suspension in the suspension reaction zone so that the reaction heat generated during oxidation of the raw material is sufficient to bring the particles to the desired temperature. Process according to Claims 1, 2 or 3, characterized in that the flow rate of the suspension in the suspension reaction zone is adjusted so that the average residence time of the suspension in the suspension reaction zone is about 0.5 to 2 seconds. 56397 15 A slurry melting furnace for applying the method according to claim 1, having a horizontal lower furnace (A) to which the lower ends of the at least one vertical slurry reaction zone (B) and the upstream flow zone (C) are connected, the slurry reaction zone having finely divided oxide sulfide sulfide - and sulphide ore or concentrate to form a suspension with air and / or oxygen and to direct this suspension downwards in the reaction zone (B) perpendicular to the surface of the melt accumulated in the lower furnace (A) to discharge the main part of the suspension into the melt and in the upflow zone (C) from its upper part, in addition to which the lower furnace has devices for removing slag and metal as well as rock from the lower furnace, characterized in that the distance between the feedstock feed point and the melt in the suspension reaction zone (B) is at most equal to the effective diameter of the suspension reaction zone. Suspension melting furnace according to Claim 5, characterized in that the ratio of the distance between the feed point and the melt to the effective diameter of the suspension reaction zone (B) is about 0.7 to 0.9 to 16 56397