SE184068C1 - - Google Patents

Description

Inventors: R Nowak and W Schuster Priority requested on 28 September 1960 (Federal Republic of Germany) The present invention relates to a chemical engineering procedure for large-scale industrial extraction of pure iron from iron ores, even minor ones, by means of a halide metallurgical process.

Preheating of iron ores in shaft furnaces or rotary rudder furnaces to pig iron by direct or indirect reduction dr kand.

The shaft furnace processes have the disadvantage that the reduction and the smelting process take place in the same room and that in addition to iron oxide, other oxides are also partially co-reduced and thus a strongly contaminated jam is extracted in the form of tack jam. This, in turn, has the disadvantage that the pig iron must be subjected to lengthy and expensive purification and refining processes during dosing pre-processing into jam or steel, e.g. research according to the Thomas and Bessemer processes.

Yid refreshment is reduced joke only levels' of joke onskyd.rda elements, such as boil manganese, silicon and phosphorus in the steel without also part of the iron is oxidized, which is lost in the form of a fire, thick smoke. This smoke is one of the most unpleasant phenomena in the ironworks, dd. it - apart from the iron losses - increases the purity of the air, and is currently a very acute problem.

The rotary rowing furnaces Oro were only lamped for high percentages, as far as possible pure iron ores for the production of iron fungus, apart from the rann process and other processes, in which only impure pig iron is extracted.

The classic blast furnace, which still masters the largest part of the world's production of tack-jam, requires pressure-, fall- and groove-resistant cabin coke, iron-rich, piece-shaped, jokes smoldering iron ores and emits an enormous amount of blast furnace gas, the utilization of which apart from the purification of the blast furnace gas with related problems, such as the recovery of the blast furnace gas sludge, the wash water circulation in water-poor areas, etc.

Lander, sasom Yugoslavia ocb. India, which has significant deposits of iron ore and lignite but no or only insignificant supply of hard coal, is concerned about importing cabin coke or using legal shaft kiln procedures or trying to experiment with new methods of producing a solid lignite coke.

The United States with its tachonite giant deposits (30-35% Fe) and Brazil with its itabirites must increase the iron content of these ores by expensive enrichment methods. Furthermore, gas reduction fluidized bed processes have already been experimented with. However, the reduction takes a very long time, because the diffusion rates in the small iron particles are small and the processes are therefore uneconomical.

In order to avoid the disadvantages of the procedures described above, new scales have been used. Efforts are made to extract pure iron directly from iron ore while avoiding a contaminated intermediate product such as pig iron. thus emerged the various halide metallurgical processes, which are based on the iron being separated from the ore in the form of a gaseous halogen compound. In most processes the iron is transferred to gaseous ferric chloride (FeCl3) or ferrochloride (FeCl2) and from these chlorides is obtained jam by reaction with oxygen or water vapor. In most cases, it is proposed to use chlorine and chlorine water in a circular process.

The principle of these procedures seems at first sight very simple and economical. The first proposals appeared about 40 years ago. Despite this, iron is not yet recovered in storm quantities according to any halide metallurgical process. The blast furnaces produce depending on size 10-100 tons of pig iron per hour.

The halide metallurgical processes are based on the separation of the iron in the form of FeCl, or FeCl2 and lead to Fe2O, or Fe. These processes can be summarized in four groups: 2— - Ore chlorination with chlorine, Ore chlorination with chlorine cotton, Reducing ore chlorination with carbon and chlorine cotton and Reducing ore chlorination with chlorine and carbon or carbon monoxide.

In most groups according to groups 13 the heat demand for foliage of the strongly endothermic reactions Fe20, (s) 3Cl2 (g) = 2FeCl3 (g) + .2 (g) (1) and Fe2O3 (s) 6HCl (g) = 2FeCl3 (g) 3H 2 O (g) (2) too large and the amnesic conversion to foliage of unfavorable thermodynamic equilibrium too small, whereas the procedures are uneconomical.

More favorable are those based on reducing chlorination with carbon or carbon monoxide and chlorine based processes according to group 4, which are based on exothermic reactions: Fe 2 O 3 (s) 3 C (s) 3 Cl 2 (g) = 2 FeC12 (g) 3 CO (g) / or Fe 2 O 3 (s) 3CO (g) 3Cl 2 (g) = 2FeCl 3 (g) 3C 02 (g) (4) However, these procedures have not been successful. The combination of reduction and chlorination seems so energetic that other metals in the gait are also cloned.

At high temperatures the reaction times are short, but such large amounts of undesired chlorides are formed that a very large amount of chlorine is lost from the circular process. When low temperatures are used, although minor amounts of undesirable chlorides are formed, the required reaction times until complete separation of the iron are too long. Due to the chlorine losses at the higher temperatures and the long reaction times at the lower ones, these processes are also uneconomical.

The object of the present invention is to provide a large-scale industrial and economically favorable process for the direct extraction of pure iron from iron ore, even low-iron ore, on halide metallurgical scale, while avoiding the disadvantages of the known cab processes and the halide metallurgical processes.

According to the invention, the ore is chlorinated at high temperatures. The reaction rate Or as a result is very large. Despite the high temperature during chlorination, the formation of undesired chlorides is largely avoided and the chloride loss becomes very low. The hitherto harmful phosphome in iron ore is extracted as a by-product in the form of valuable phosphoric acid. Phosphorus-poor or phosphorus-free ores can be continued with phosphorus-containing substances. The heat released during the process is utilized and utilized. The ore does not have to be in piece form. As a reducing agent, every type of coke, even Oven coke, is lignified from lignite.

As the edge arises in the reducing chlorination of iron ore and ferric chloride also silicon tetrachloride, aluminum chloride, titanium tetrachloride, the chlorides of phosphorus, sulfur etc.

It has now been found that iron oxide (Fe 2 O 3) at temperatures between 800 and 1200 ° C reacts with silicon tetrachloride (SiCl 4), aluminum chloride (AlCl 3), titanium tetrachloride (TiCl 4) and phosphorus pentachloride (PC1) and the had sulfur chlorides (S2Cl2, (PC13) in the presence of chlorine (C12) to form ferric chloride (FeCl3). In addition, the oxides of silicon (SiO2), of aluminum (Al2 O3), of titanium (TiO2) and of sulfur (SO2) and phosphorus oxychloride (POCl3) are formed.

Sales take place only in the absence of reducing domains. The reactions were exothermic, the reaction rates were high and the turnover was practically quantitative.

In order to avoid the chlorine losses resulting from the known processes, chlorine is reacted according to the invention in a reaction chamber (reduction chlorination chamber) with a mixture of crushed milk and a probe-containing carbonaceous reducing agent at a temperature between 800 and 1200 ° C and then the gaseous reaction products together with chlorine in another room (oxidation chlorination room) in contact with maim - but in the absence of a reducing agent - also at a temperature of between 800 and 1200 ° C. and this is charged with maim frau oxidation chlorination tube and carbonaceous reducing agents, while introducing new maim into the oxidation chlorination chamber. The amount of carbon fed into the chlorination chamber corresponds to the stoichiometric iron oxides and any phosphates present in the ore so that they can be reduced and chlorinated to FeCl3 and POCl3. The amount of chlorine introduced into the reduction chlorination chamber corresponds stoichiometrically to the iron content of the water content of the reducing agent and the content of phosphorus in the ore and the reducing agent so that FeCl4 and POCl3 can be formed. Darvid maste man. always take into account the amount of reducing agent entering the reduction chlorination chamber and the ore finger introduced into the oxidation chlorination chamber.

The gaseous reaction product formed in the oxidation chlorination chamber contains practically only ferric chloride, carbon dioxide and hydrochloric acid. Chlorine choice Midas to folide of the moisture content of the reducing agent. In order to obtain as little chlorine water as possible, the reducing agent must be very poor in water. DA e.g. layer temperature coke (Schwelkoks) contains much more moisture than coke plant coke (Kokereikoks) where it is advantageous to heat layer temperature coke to about 1200 ° C, before it is used for the reducing chlorination. The layer temperature coke is degassed and its water content is significantly reduced. The heat of combustion has the effluent gas Or sufficient for the heating, drying and degassing of the layer temperature coke. The degassing of the layer temperature coke can be carried out as a result of combustion of its own volatile constituents. The chloride gas mixture is cooled after cooling the oxidation chlorination chamber to about 320 ° C and freed from entrained dust so that during further cooling it should not be able to enter the separating solid ferric chloride (Fe2C16). From the dust-free gaseous mixture is then separated at a temperature of between 110 and 140 ° C in a "Fe2Cl2" condenser »ferric chloride in solid form.

The pre-cooling of the gaseous reaction product to about 320 ° C after the oxidation of the oxidation chlorination chamber takes place, typically during simultaneous dust separation, e.g. in a cooling cyclone. This removes any present small amounts of heavy liquid chlorides, e.g. MnCl „CoCl 2 and CrCl„ They are re-fed together with the dust from the cooling cyclone and escape maim to the oxidation chlorination chamber. Hdr evaporates the Ater, so aft between the oxidation chlorination chamber and the cooling cyclone an internal circular process arises. However, the formation of larger amounts of volatile chlorides counteracts the partial pressures of these chlorides now present in gaseous mixtures. This prevents the contamination of the ferric chloride by non-ferrous metals.

The hydrochloric acid and carbon dioxide containing the residual gas are washed in an absorption apparatus with water, whereby HCl is absorbed, while CO, leaves the plant.

The hydrochloric acid obtained by dewatering is electrolysed, whereby chlorine is recovered. The TV water was suitably used in a circular process between the electrolysers and the absorber. Yes. The HCl absorption is strongly exothermic and the gas mixture itself enters the absorption apparatus at a temperature of about 130 ° C and must be cooled. Of course, chlorine water can also be converted to chemical chlorine by chemical means.

The solid ferric chloride from the Fa2Cl2 condenser is combusted with oxygen to iron oxide (Fe2O2) and chlorine (C12) at a temperature of 700-800 ° C.

The oxygen is brought to a temperature of 800-950 ° C together with the solid approximately 120 ° C hot ferric chloride. It is evaporated and incinerated at the same time, whereby a combustion temperature of between 700 and 800 ° C settles. However, the ferric chloride can be heated to about 310 ° C, then smashed and then combusted with about 400 ° C hot oxygen. The chlorine is separated from the iron oxide and re-introduced together with the chlorine recovered during the HCl electrolysis into the reduction clearance chamber.

The iron oxide arising during combustion is reduced in a room (reduction room) with reducing gases, e.g. generator gas, water gas or natural gas, to which the water formed by the HCl electrolysis was added, on the edge of salt to pure jam. Delta can be extracted as a powder or melted in connection with the reduction. During the melting, other elements can be alloyed and in this salt any steel can be produced, free from undesirable impurities.

Such as edge contain technical, reducing gases mostly gaseous sulfur compounds.

To avoid contamination of the iron by sulfur, the reducing gases are first brought into contact with iron powder, which removes the sulfur from the gases. Only then were the gases used to reduce the jam oxide. The sulfur-containing iron powder is added to Ores together with the coke to the reduction chlorination chamber, so that no iron loss occurs during the process.

For the chlorination, carbon monoxide can be used instead of a solid carbonaceous reducing agent, which is introduced together with the chlorine into the reduction chlorination chamber.

The most economical is the use of solid, carbon-rich reducing agents, because elemental carbon reduces twice as much iron oxide as the equivalent amount of carbon monoxide. Pure carbon monoxide is Mr expensive for the present andamal. In generator gas, water gas or coking plant gas, the carbon monoxide is admittedly cheaper, but is so strongly emitted by CO, and N, that the reaction rate during maline chlorination is reduced and in addition large amounts of inert gases must be transported as ballast gases. Furthermore, the whale and water vapor of these industrial gases react during the chlorination to chlorine tea, so that a large part of the chlorine used is lost to the chlorination.

Air can be used to burn the ferric chloride in the stable for acid. However, then, together with the chlorine formed during combustion, the nitrogen of the air enters the chlorination chamber, whereby the reaction rate is reduced as a result of the dilution and the total amount of gas is substantially equalized.

Furthermore, it has been found that the gaseous phosphorus chloride (POCl 3) at temperatures of between 110 and 1 ° C with water or water vapor is quantitatively converted to phosphoric acid and hydrochloric acid: POCl 3 H 2 O = H 3 PO 4 3HCl (5) other chlorides including gaseous phosphorus trichloride and small amounts of phosphorus pentachloride. In the oxidation chlorination chamber, these chlorides are converted to gaseous ferric chloride and gaseous phosphorus oxychloride.

In connection with the cooling and dusting of the gaseous reaction mixture after the chlorination and after the separation of solid ferric chloride, according to the invention, the gaseous mixture leaving water or water vapor was added to the frail Fe 2 C 16 condenser. In doing so, the phosphorus oxychloride reacts to phosphoric acid and chlorine. The phosphoric acid is formed in the form of a mist, which is absorbed on the edge in hot phosphoric acid.

From the residual gas, the frail choice of the reducing agent and the chlorine water arising in the H, PO formation are diluted with water or dilute hydrochloric acid.

By the recovery of phosphoric acid in accordance with the invention, the economy of the process is substantially improved. Due to this, it is advantageous that in the extraction of jam from phosphorus-poor or phosphorus-free iron ores, phosphorus-containing substances are mixed, e.g. rafosphate frail Florida or Morocco with about 14.5% phosphorus.

The loss of small amounts of chlorine, which are mechanically and chemically bound in the corridor and removed with it from the reduction chlorination chamber, is inevitable.

According to the invention, the chlorine loss is replaced by the chlorine recovered by alkali chloride electrolysis together with that in the Fe 2 C 16 combustion. and the chlorine obtained in the HCl electrolysis is introduced into the reduction chlorination chamber.

The water formed in the alkali electrolysis is mixed with the Iran HCl electrolysis in it. reducing the gas used to reduce the iron oxide. In addition to chlorine and hydrogen, alkali hydroxide is also formed in the alkali chloride electrolysis. This can either be extracted and distributed as a by-product or used in the process of enriching valuable heavy metals from the gait and thereby regenerating into alkali chloride. This is accomplished by washing the gait with a dilute solution of the alkali hydroxide curing the electrolysis, thereby obtaining an alkaline solution of all the chlorides of the gait. This solution is treated with CO, or with the exhaust gas from the HCl absorption apparatus, which contains considerable amounts of CO, CO, reacts with the chlorides in the alkaline solution, whereby a carbonate sludge precipitates, which contains all the metals present in the gait in the form of volatile chlorides. , e.g. manganese, chromium. After separation of the sludge, the solution contains only alkali chloride, which is etherified to the electrolysis. Any non-ferrous metals can be recovered from the carbonate sludge.

The energy requirement required for electrolytic chlorine recovery can be completely offset by the heat emitted during the process.

For this purpose it is converted in the chlorination of the ore, in the combustion of the ferric chloride and in the HCl absorption liberated and in the cooling of the gaseous reaction products after the ore chlorination, of the gait, of the chlorine and of the exhaust gases from the reduction treatment of the iron oxide. was used for the electrolytic chlorine extraction.

In the process according to the invention, ground coke is heated by means of hot nitrogen and. ground ore by hot flue gases and dried, a mixture of maid maim and coke is treated with chlorine and maid maim alone with a chloride gas mixture, nitrogen is heated at the hot gait and oxide dust is reduced by gases to pm. For such processes, the most diverse known devices can be used, such as simple containers, rotary rowing furnaces or fluidized bed towers.

Plants consisting of several containers, which contain solid substances, which are permeated by a gas, Arc before kanda. In this case, according to the cascade principle, the solid substance is transported from the first to the last container and the gas from the last to the first. These procedures are cumbersome and the plants, in comparison with their size, have a relatively small capacity. In addition, before the flow rate, the gases in the containers do not exceed a certain extent, because otherwise solid particles in excessively large amounts are entrained. the life of rotary kilns, in which solids are continuously brought into contact with gases, before the flow rate of the gases is not so great that a lot of dust is entrained. When, for example, at a. chemical process I. ex. the ore reduction, or a physical process, I. ex. drying or heating of a finely ground solid blank, for the treatment of the solid blank a considerable amount of gas is required, almost the rotating tube furnace having a very large internal width for the flow rate of the gas to be sufficiently small.

During the supply of hydrine in endothermic processes or in the recovery of the effluent in exothermic reactions, the hydrothermal vents in the containers drew. The heat losses are therefore large, because the required residence times for the solid substances are long in these devices.

The multi-stage vortex layer processes admittedly allow for excellent heat transfer between gas and solid matter, but the Oxen vortex tower towers (consisting of several whirlpools) must often have a large internal width, so that the gases will only cause the vortex and not be able to feed the solid matter. However, the finest dust particles are always carried by the gas, which can lead to blockage of the flow bottoms.

In the process described in the foregoing procedure, the content of very fine dust in the solid substances must be as small as possible in order for no large losses to occur and for the costly dusting device to be unnecessary.

According to the invention, the aforementioned antiquities and economics of the process are substantially improved, since the gases in cyclone batteries of the edge type are continuously brought into effect and energetically mixed with dust-fine decomposed coke, maim and iron oxide as with the countercurrent principle. The mixtures can be quickly: heated and cooled. The heat transfer between gas and the dust-fine material is excellent and the heat losses dragged a lot 16.ga. The reaction rates Arc are extremely large and, consequently, the reaction times are surprisingly short. With relatively small plants, high production capacity can be achieved.

The principle of the cyclone batteries meant that several cyclones (centrifugal dust separators) were used as reaction chambers and connected to each other in such a way that in the device as a whole according to the countercurrent principle chemical and physical processes Aga space and at the same time in the individual cyclones separation processes.

Cyclone batteries are used in the Mom cement industry to heat the marl dust (marl dust) or the clinker combustion by means of hot exhaust gases. The individual cyclones consist of a ceramic lining with a plate jacket. For calcination of joint soil, cyclone batteries have previously been proposed. Individual cyclones are also used as reaction chambers, as e.g. the known cyclone fires, which internally have a refractory lining, which is surrounded by a mantle consisting of coolers, which are externally heat-insulated and covered with plate.

The cyclone batteries used for the process according to the invention consist of several cyclones, the number of which of course depends on the reaction rate, i.e. on the temperature, the grain size and other factors.

For the reducing and oxidizing chlorination which is exothermic, the cyclones are built double-walled or surrounded by pipes and externally with a heat-insulating layer. Water or steam is passed through the double jackets or pipes, which absorb the heat released from the chemical reactions. For protection against heat and chemical attack by chlorine and chlorides, the inside of the cyclones are provided with heat-resistant, heat-insulating and chemically resistant charges. Of course, the pipelines between the cyclones are protected analogously to heat and chemical attack and are surrounded by double jackets or pipes and heat insulated.

In order to possibly prolong the residence time of the mixtures in the device without substantially increasing the number of cyclones, vortex chambers are embedded in the mixture conducting pipelines between the cyclones, in which - depending on the internal width and length of these chambers - the reaction mixtures remain for a certain time. next cyclone and there are separated.

As already mentioned, the cyclone batteries were also used for the reduction of the iron oxide and for heating the nitrogen with the gait dust. These are heat insulated so that the heat losses will be as small as possible.

The mode of operation of a cyclone battery according to the invention is explained in more detail with reference to the drawing of Fig. 1a. In the left end of the cyclone battery, lead is introduced and in the right end the mixture of dusty coke and maim. In front of each individual cyclone, dust and gas are first mixed with each other and transported into the cyclone, where they are separated from each other and reach the cyclone in the opposite direction. Due to the countercurrent principle and the large, highly active surface of the fine dust, the marked heat transfer between swirling gases and dusty solids on one side and the very good heat transition between these swirling mixtures and the cradles of the cyclones on the other hand and the practically complete the thermal closure outside the device is as well as the thermal efficiency of the process according to the invention.

Embodiment Example I.

Fig. 2 shows a schematic representation of the principle of a plant for carrying out the process set according to the invention. The plant (50 tonnes of pure jam per hour) mainly consists of the following parts: 1 - Separation device for coke 2 - Drying device for the decomposed coke (280 ° C) 3 - Separation device for iron ore 4 - Drying device for the decomposed ore (800 ° C ) - Cyclone for the drying exhaust gases (heat-insulated) 6 - Washing plant for the drying exhaust gases 7 - Reduction chlorination room (800 ° C) 8 - Oxidation chlorination room (800 ° C) 9 - Pipeline for the 800 ° C hot gaseous reaction products after chlorination - Cooling cyclone for the 800 ° C the gaseous reaction products alter the chlorination 11 - Pipeline for the 320 ° C hot gaseous reaction products after the chlorination 12 - Hot gas filter (320 ° C) 13 - Fe2C16 condenser (120 ° C) 14 - HaPOr reactor (140 ° C) - HG1 absorber -16 - HO Electrolyser 17 - Air subdivision device- 18 - Combustion device for Fe2C16 (730 ° C) 19 - Pipeline La. the Fe20 hot 730 ° C - Reduction room (1000 ° C) 21 - Cooling cyclone for cooling the hot C12 and for the Fe2 O2 separation 22 - Fine dust filter for the Fe203-Cl separation (30 ° G) Transport line for the hot aisle (280 ° C) - N2 heater (280 ° G) 26 - Pipeline for cold N, 27 - Cooler for the hot aisle 28 - Pipeline for the 280 ° C hot N2 .29 - NaCl electrolyzer - Pipeline for electrolytically recovered Cl 31 - Gas generator 32 - Pipeline for H2 frail NaCl electrolyser 33 - Pipeline for H2 frau The HCl and NaCl electrolysers 34 - Connection between gas generator and reduction chamber - Kyleyclone for the 1000 ° C hot exhaust gas frau. Fe20, --reductionen 36 - Flow line for the cold exhaust flan Fe20 rreductionen 37TwattenIdggning for the cold exhaust gas from the Fe20 a -reductionen 38 - Narrow furnace (1000 ° C) for the pure iron 3902 -heater (860 ° C) Based on this plant with a production of 50 tons of pure iron per hour as an example is described in the following recovery of 1 ton of jam according to the invention.

- - The composition of the iron ore: Fe 30.0% Al 2 O 3 8.0% Mn 0.2% CaO 4.0% 0.5% MgO 2.0% SiO 2 25.0 °, / ,, H 2 O 10.0% Sasom brown collar temperature coke (Braunkohlenschwelkoks) was used: The composition of the brown collar temperature coke: 16% s1% 1120 20% H2% ash15% 0 + N 1% 285 kg brown collar temperature coke is finely divided in the probe dividing device 1 arida to a grain size of 0.05 mm and dried in the opposite direction through the pipeline 28 coming 280 ° C hot suffocation. 3,333 kg of iron ore is finely atomized in the separating device 3 also down to a grain size of a maximum of 0.05 mm and dried in the drying device 5 by means of an oil burner and heated to 800 ° C. The drying exhaust gases from the drying devices 2 and 4 are released 6, said that the Minna plant is dust-free.

The 280 ° C hot dusty coke from the dryer 2 and the dusty coke-ore mixture Iran. the cyclone 5 enters the reduction chlorination chamber 7. From the cooling cyclone 10 the dust separated therein is introduced together with it. 800 ° C hot dusty ore in the oxidation chlorination chamber S. The dusty ore is transported through the oxidation chlorination chamber 8 to the reduction chlorination chamber 7, where it is mixed with it. dusty coke. Fran. the reduction chlorination chamber 7 removes the iron-free gait and the coke ash through the transport line 21. 690 NM? (= 2,226 kg) chlorine with a temperature of 30 ° C in the reduction chlorination chamber 7 and is heated as a result of contact with the gait in the countercurrent to 800 ° C, whereby the gait is cooled to 280 ° C. is released as a result of exothermic heat reactions, which are recovered by cooling.

The chlorine flows through the reduction chlorination chamber 7 and the oxidation chlorination chamber 8 in a direction opposite to that of the dust. The gaseous reaction products leave the oxidation chlorination chamber 8 through the pipeline 9, are freed of dust in the cooling cyclone 10 and are thereby cooled to 320 ° C and flow through the pipeline 11 to the hot gas filter 12 for fine dusting.

In the Fe2C16 condenser 12, Iran separates the pure gaseous mixture at 120 ° C solid ferric chloride. The remaining gaseous mixture granulates the Iran Fe2C16 condenser 13 into the H3PO cracker 14, into which 294 kg of cold water is injected in mist form. The water evaporates and forms with phosphorus oxychloride 617 kg of 86% phosphoric acid in the form of an areosol, which is absorbed in approximately 86% phosphoric acid. During the formation of the phosphoric acid of the phosphorus oxychloride, the temperature in the H3PO4 reactor rises from 120 to 140 ° C.

The practically only CO, and HCl containing 140 ° C hot gas mixture flows Iran H, the PO reactor 14 into the KCl absorber 15, where chlorine water is absorbed. The absorption takes place with cold about 10% HCl in countercurrent. The heat released during the HCl absorption and the heat given off by the gases are recovered in the HCl absorption apparatus 15 by cooling.

The formed approximately 33% hydrochloric acid is passed to the HCl electrolyzer 15 in the HCl electrolysis, whereby 81 Nm3 (263 kg) of chlorine and 82 Nm3 of irate are recovered. After the electrolysis, the approximately 10% hydrochloric acid Ater für HCl absorption was used in the HCl absorber 15. 1500 Nm3 of air is divided in the air subdivision device 17 1300 Nm3 oxygen and 1200 Nm3 nitrogen. 300 Nm3 of oxygen is heated in the furnace heater 39 by means of an oil burner to 860 ° C.

From the Fe 2 Cl 2 condenser 13, the 120 ° C hot solid ferric chloride is transported (for example by means of a snack) to the combustion device 18, where it collides with the hot oxygen. The ferric chloride is evaporated and incinerated into iron oxide particles, whereby a combustion temperature of 730 ° C is established.

Most of the hot iron oxide (about 90%) is separated in the incinerator 18 Iran Idol% The 7 ° C hot chlorine is cooled in the cooling cyclone 21 to 30 ° C, whereupon it releases some more iron oxide and is finally freed in the fine dust filter 22 from the finer iron oxide residues. The iron oxide from the combustion device 18, the cooling cyclone 21 and the fine dust filter 22 is transported through the pipeline 19 into the reduction chamber 20.

In the combustion device 18, 1425 kg of Fe, O, and 590 Nm3 (= 1903 kg) of chlorine are formed. In NaCl electrolyzer 29, 68 kg of sodium hydroxide, 19 Nm3 (= 60.5 kg) of chlorine and 19 Nm3 of irate are recovered electrolytically from 100 kg of sodium chloride. The chlorine is combined through the pipeline 30 together with the chlorine from the HCl electrolyzer 16 in the pipeline 23 with the chlorine coming from the combustion device 18 and is introduced into the reduction chlorination chamber 7 (opposite to the hot, iron-free gait).

From the air subdivision device 17, 700 Nm3 of nitrogen is passed through line 26 to No. heater 25, where the nitrogen is heated by the hot aisle countercurrent to 280 ° C and the aisle is cooled to 120 ° C. drying of the brown collage temperature coke. 1613 kg of the mixture gait and coke ash come frail Nrupphettaren 25 with a temperature of 120 ° C into the cooler 27, where it is cooled to 20 ° C. The cold powder Wires to the warp heap, but can e.g. used for the production of building materials or for the extraction of precious metals present therein.

In the gas generator 31, 530 kg of brown collage temperature coke, air and water vapor 1800 Nm3 - -7, generator gas is generated and passed at a temperature of 10000 G to the reduction chamber 20. 101 Nm3 pipeline 33 to the generator gas. The reducing gas mixture (1901 Nm3) enters the reduction chamber 20 through line 34, where 1425 kg of iron oxide is reduced to 1 ton of pure jam at 1000 ° C. free.

The iron is extracted as pure iron powder or melted in the smelting furnace 38. The iron powder can be carbonized during the reduction by means of a carbon monoxide or the hydrocarbons, e.g. methane rich gas. A powder of the purest carbon steel is obtained, which is of great importance for the preparation of molds on powder and sinter metallurgical vehicles.

However, even from the pure iron malt, one can produce the habit of arbitrary steel, by adding the required elements, e.g. carbon, silicon, manganese, crown and nickel.

By means of the heat recovered in the various parts of the plant by cooling, the steam is used, which is used for the extraction of electrical energy. The extracted heat quantities of approximately 3,350,000 kilograms of calories give 880 kilowatt hours. This amount of energy is sufficient for the operation of the HCl and NaCl electrolyses. The HCl electrolysis consumes 660 kilowatt hours and the NaCl electrolysis 200 kilowatt hours.

EXAMPLE 2 This example relates to a plant with a reindeer iron production of 50 tonnes per hour and describes a process for the recovery of 1 tonne of pure titanium magnetite iron. In this case, if the flake phosphoric acid is not recovered, the H3PO4 reactor is not required (Fig. 2).

Composition of the ore: TiO 2 16.70% (10.00% Ti) FeO 20.72% (16.10% Fe) Fe 2 O 2 12.74% (8.92% Fe) SiO 2, 23.07 ° A Al, 02 17.80% MnO 3.13% CaO 2.21% MgO 1.04% Alkaloxide 2.19% H 2 O 0.% As a reducing agent coke plant coke was used: Composition of the coke: 81.00% ash 8.00% H 2 O8.00% 0 N1.60% 0.90% 0.50%. 156 kg of coke is finely divided in the decomposition device 1 to a grain size of a maximum of 0.05 mm and dried in the drying device 2 with it through. pipeline 28 in countercurrent coming 520 ° C, hot stuffed. 4000 kg of titanium magnetite is finely divided in the probe dividing device 3 likewise to a grain size of a maximum of 0.05 mm and dried in the drying device 4 by means of an oil burner and heated to 800 ° C. The drying gases & The drying devices 2 and 4 are freed from dust in the heat-insulated cyclone 5 and washed in the washing plant 6, so that the lamina plant is dust-free.

The 520 ° C hot coke dust from the dryer 2 and the coke-ore-dust mixture from the cyclone 5 enter the reduction chlorination chamber 7. From the cooling cyclone 10 the separated dust is introduced together with the 800 ° C hot mill dust into the oxidation chlorination chamber 8. The ore dust is transported to the oxidation chamber the reduction chlorination chamber 7, where it is mixed with the coke dust. From the reduction chlorination chamber 7, the iron-free gait and coke ash are removed through the transport line 24. 610 Nm3 (= 1963 kg) of chlorine with a temperature of 30 ° C is introduced into the reduction chlorination chamber 7 and heated to 800 ° C as a result of the contact with the gait in countercurrent. , the gait being cooled to 520 ° C. In the hot chlorination rooms 7 and 8, heat is recovered as a result of exothermic reactions, which is recovered by cooling.

The chlorine flows through the reduction chlorination chamber 7 and the oxidation chlorination chamber 8 in a direction opposite to that of the dusty material. The gaseous reaction products leave the oxidation chlorination chamber 8 through the pipeline 9, are freed of dust in the cooling cyclone 10 and are thereby cooled to 320 ° C and flow through the pipeline 11 into the hot gas filter 12 for fine dusting.

In the Fe3C16 condenser 13, solid ferric chloride is separated from the purified gaseous mixture at 120 ° C. The remaining gaseous mixture, which contains practically only CO2 and HCl, goes to the HCl absorber Lions apparatus 15, whereby chlorine cotton is absorbed. The absorption takes place in countercurrent with cold about 10% HCl. The heat released during the HCl absorption and the heat given off by the gases are recovered by the HCl absorption apparatus 15 by cooling.

The formed approximately 33% hydrochloric acid is passed from the HCl absorber 15 to the HC electrolyzer 16, whereby 9 Nm3 of chlorine and 9 Nm3 of hydrogen are recovered. After the electrolysis, the approximately 10% hydrochloric acid was again used for HCl absorption in the absorber 15. 1500 Nina air is divided in the air subdivision device 17 into 300 Nm3 oxygen and 1200 Nm3 nitrogen. The 300 Nms of oxygen is heated in the furnace heater 39 by means of an oil burner to 860 ° G.

From the Fe2C16 condenser 13 the solid ferric chloride (120 ° C) is transported (for example by means of a snack) to the combustion device 18, where it collides with the hot oxygen. : The ferric chloride is evaporated and combusted to iron oxide and chlorine, whereby a combustion temperature of 730 ° C is established. Most of the hot iron oxide (about 90%) is separated in the combustor 18 from chlorine. The chlorine is cooled in the cooling cyclone 21 to .30 ° C, whereupon it releases an additional part of iron oxide, and is finally released in the fine dust filter 22 from the finest residues of iron oxide. The iron oxide Iran combustor 18, the cooling cyclone 21 and the fine dust filter 22 are transported through the pipeline 19 to the reduction chamber 20.

In the combustion device 18, 1425 kg of Fe2 O3 and 590 Nm3 (= 1903 kg) of chlorine are formed. In the NaCl electrolyzer 29, 53.3 kg of sodium chloride electrolytically recover 36.5 kg of sodium hydroxide, 11 Nm3 (= 32.3 kg) of chlorine and 11 Nm3 of vale. The chlorine is combined through the tubing 30 together with the chlorine frail HCl electrolyzer 16 in the tubing 23 with the chlorine coming from the Iran combustion device 18 and is introduced into the reduction chlorination chamber 7 (opposite to the hot, iron-free gait).

From the air subdivision device 17, 200 Nm3 of nitrogen is passed through the pipeline 26 into the heater 25, where the nitrogen of the hot gangue is heated in countercurrent to 520 ° C and the gangue is cooled to 474 ° C. drying of the coke. 2684 kg of the mixture of gait and coke ash enter the Nrupphetter 25 with a temperature of 474 ° C into the cooler 27, where it is cooled to 24 ° C. The completely iron-free mixture of gait and coke ash contains 400 kg of titanium (approx. 15%), and was used as a valuable starting material for the recovery of titanium.

In the gas generator 31, 1882 Nm ° of water gas is generated, which at a temperature of 1000 ° C is led to the reduction chamber 20. 20 Nm3 of water from the NaCl electrolyzer 29 was added through the pipeline 32 and the Iran HCl electrolyte 16 through the pipeline 33 to the water gas. The reducing gas mixture (1902 Nm3) enters the reduction chamber 20 through line 34, where 1425 kg of iron oxide is reduced to 1 ton of pure jam at 1000 ° C.

By means of the heat recovered in the various parts of the plant by cooling, the steam is used, which is used for the extraction of electrical energy. The recovered amount of heat of about 2,656 -000 kilograms of calories saves 700 kilowatt hours. Of this, 180 kilowatt hours are consumed in the HCl and NaCl electrolysis (70 and 110 kilowatt hours, respectively), so that a total of 520 kilowatt hours is required. available for other purposes.

The method according to the invention means an undeniable progress compared to the current state of the art. Ore with low half-strength, which is not used in blast furnaces due to the danger of constipation, is a great choice for the method according to the invention, in any case each ore is finely divided, and in these ores the probing costs are less than in hard ores. as even the sorting of the ores lapses, the ore price is saved. Poor iron ores with, for example, 30% Fekunnantannagon orientation are directly processed into pure jam. The hitherto unfavorable phosphorus content of jammalm Or according to the invention in favor of the economy of iron extraction. Ferrous titanium ores can za. economically completely freed from jam. Also from other ferrous materials, such as e.g. frail waste in the extraction of non-ferrous metals, jam can be recovered. According to the invention, land which does not ago hard coal titanium lignite can produce pure jam and high-grade steel on a large scale economically. The production costs of the pure iron produced from the process according to the invention or the high-quality steel produced therefrom are significantly lower than those for steel produced according to hitherto known methods.

Claims (9)

Patentanspra.k: Procedure For the recovery of pure jam and / or iron oxide by ore chlorination, the recovery of chlorine by preheating of formed iron chloride and the reduction of jam oxide formed in the combustion to jam, can clarified that in a reduction chlorination chamber chlorine is reacted with a mixture of , and after solid carbonaceous reducing agent at a temperature between 800 and 1200 ° C, that the gaseous reaction products and chlorine Iran reduction chlorination chamber are brought into contact with maim and possibly phosphates in franyaro of a reducing agent in an oxidation chlorination chamber at a temperature between 800 and 1200 ° C, that the free-flowing gait is removed from the reduction chlorination chamber, that the ore from the oxidation chlorination chamber mixed with the son-cured carbonaceous reducing agent is introduced into the reduction chlorination chamber, that the oxidation chlorination chamber be charged with gas, that the oxidation chlorination chamber paralyze gaseous reaction products to At the same time, Iran is entrained with entrained dust, which is returned to the oxidation chlorination chamber, to separate ferric chloride from the dust-free gaseous reaction products at a temperature between 110 and 1 ° C in a Fe3C16 condenser, so that the Fe2C16 condenser-leaving gas mixture is washed. with water, that chlorine is electrolytically recovered from the hydrochloric acid-containing water water, that the ferric chloride is combusted with oxygen at a temperature between 700 and 800 ° C to iron oxide and chlorine, which chlorine is introduced into the reduction chlorination chamber together with the electrolytically recovered chlorine. the iron oxide with reducing gases and the choice released in the electrolytic chlorine extraction is reduced to iron. 2. A process according to claim 1, characterized therefrom, aft in the reduction chlorination chamber in the stable of a solid carbonaceous reducing agent inf ores carbon monoxide. - —9 3. A process according to claims 1 and 2, characterized in that the 110 to 140 ° C hot ferric chloride separated in the Fe2C16 condenser is brought into contact with 800 to 950 ° C hot oxygen and incinerated at 700 to 800 ° C. 4. A process according to claims 1 to 3, characterized in that air is used for the combustion of the ferric chloride instead of oxygen. Process according to claims 1 to 4, characterized in that water or water vapor added to the Fe, C16 condenser laminated gas mixture at a temperature between 110 and 140 ° C, that formed phosphoric acid mist is absorbed in hot phosphoric acid and that from those remaining after the absorption treatment the chlorinated gases are washed with water or dilute hydrochloric acid. Process according to Claims 1 to 5, characterized in that phosphate-containing pads are mixed into the ore before entering the oxidation chlorination chamber. 7. A process according to claims 1 to 6, characterized in that by alkali chloride electrolysis alkali hydroxide, hydrogen and chlorine are recovered, and that this together with the chlorine frail Fe2C18 combustion and the chlorine Iran HCl electrolysis is led into the reduction chlorination chamber. Process according to claims 1 to 7, characterized in that the chlorine released during the chlorination of the grit, during the combustion of the ferric chloride and during the HCl absorption and the cooling of the gaseous reaction products after the ore chlorination, the hot gait, the hot chlorine after the combustion and the hot exhaust gases after the reduction treatment recover the heat converted into electrical energy, which is used for the electrolytic chlorine recovery. 9. A method according to claims 1 to 8, characterized in that for heating and drying of maid coke and maid maim the reducing and oxidizing chlorination, heating of nitrogen with the hot dusty gait and reduction of the dusty iron oxide with reducing gases to jams are used by cyclone i and f Or sig edge kind. Request publications: