SU30155A1 - Device for reducing metal ores - Google Patents

Description

(103)

The temperature maintained in each individual section, as well as the amount of heat supplied to it, can vary widely. However, during the processing of iron ore and with the reduction of Fe2O3 in Fe04, the temperature in the first stage is preferably maintained at up to 500 ° in the presence of reducing agents, which may be carbonaceous or hydrogen-containing gases, rising from two lower positions. To restore ResO4 in FeO in over the CE, it is best to maintain a temperature in the range of 500 to 700 °, using a wide range of gases, rising from pot C, the composition of which must correspond to a predetermined proportion that varies approximately from 30% CO and 70% of CO2, and more CO and 40% of CO2. It is recommended to keep the temperature in the range from 700 to 1100 ° C and the ratio of CO to POP varying from 60% to 95% CO. The amount of heat delivered is distributed when the iron ore is reduced. As follows: about 60% in C? C where the final reduction takes place, about 22% in C # and about 18% in C5. The above data are not necessary when carrying out the present invention, but should facilitate the understanding of the described method.

In order to make possible the complete reduction of metal oxides in the reduction zone, it is desirable to obtain as completely as possible the same temperature throughout the mass of the material being processed, which is in this particular area, in other words, the heat penetration should be the same both in the center of each ore column and at the outer edges of the post.

This task can be solved quite well by using a mine that has a cross section

 The shape of a long and narrow rectangle, especially if a rather large ore and a large reducing material are processed, since in this case small gas bags formed between the ore pieces promote heat transfer through the entire thickness of the material and uniformly heat it. In order to obtain the same result with fine ore, it is proposed to divide each individual shaft, 2, etc., into several parallel mines 7 (Fig. 2). The latter have an approximately rectangular cross-section and are separated from each other by field gas gaps 8, so that the combination of several such small mines forms, as shown in FIG. 2, one common shaft having an elongated and narrow cross section. When dividing each large shaft into a series of small mines, not only does the advantage given to the elongated and thin ore column remain, but, in addition, the flat thin column is broken into several separate columns, allowing heat to pass between the latter, contributing to the heating of the central parts of each continuously moving pillar of ore. Apart from the fact that heat flux penetrates in several places the ore flow, inside each shaft 7 is placed a gas outlet pipe 9, which serves to remove gas from the mine, made of metal, filled with upward gases, resulting in heat transfer to the center of each shaft and heats it from the inside. the contents of the latter.

At each mine, the pipe 9 comes down to the point, which lies just above the last recovery som C (Fig. 1). At some points located at a certain distance from the lower end of each pipe I, there are located inlets / О-for removal of gases from certain points as they form. FIG. 6 shows, on an enlarged scale, a detail as an example of such an intake opening. Due to the presence of several cones having different constant temperatures, and due to the use of diverse oxides and reducing agents in different places of the mines,

continue the pipe P down the recovery zone.

Heat for the recovery process can come from various sources. In the example described, the heat is delivered by the corresponding burners 5 and 4. To heat the recovery zone, there is a range of longitudinal heating chambers 11 separated from each other by horizontal partitions of the heating chambers 11, which at opposite ends are connected to each other by passages 72 (Fig. 3 and 4 ) so that a winding path is formed for the combustion products.

The burners 13 and 14 of each heating system are arranged in turns at two opposite ends, for example, the burner / 5 is placed at one end of the heating chamber 11, and a similar burner 14 is placed at the opposite end of the same chamber 11 located along the other cfopOHy shaft ( Fig. 3 and 4).

Separated by horizontal walls and connected with each other heating chambers 11 are connected at the lower end with zigzag cooling channels 15, and at the upper end with heating chambers 16 for preheating (Figs. 1, 3 and 4). The latter are connected at the top to a corresponding exhausting boar equipped with a passage adjustment device so that the movement of hot gases upwards can be controlled both by the heating chambers 11 of the reducing zone and by the heating chambers / 5 of the heating zone.

Due to the location of the individual throats 75 and 14 on both sides of the rebuilding shaft (fig. 2), the temperature can be adjusted to some extent for each given heating pattern. For example, the temperature at the end of the chamber at the entrance of one burner may be approximately 1300 °, and at the opposite end of the same chamber drop to 1100 °. The burner installed on the opposite side of the shaft will of course be adjusted so that it will give the opposite result, so that in general, the temperature throughout the mine will be approximately

constant However, in order to obtain with equal confidence the temperature equalization across the entire width of the shaft within one horizontal strip, it is proposed to use a series of horizontal chambers of buffer chambers 77 placed between each heating chamber {Chamber 77 and shafts 7 (Fig. 1 and 2).

The buffer chambers 77 are interconnected by transverse passages 8 (Fig. 2), as a result of which a uniform temperature is maintained around all the mines 7, which can be adjusted, if desired, for a given horizontal plane or joint. Thus, in order to maintain a constant temperature in the mines at level C, there are burners 13 and 14 installed on opposite bars of the burner shaft 13, 14 inserted into the ends of the chambers 77 and creating a known temperature inside these chambers, which is equalized and evenly distributed across the width of the shafts Saa C using intermediate buffer chambers 77 (Fig. 1).

Each buffer chamber 77 can be separated from the heating chamber 77 adjacent to it, but it is better to arrange a small number of holes at one end of the partition separating the adjacent chambers 77 and 77. The porosity or thickness of the holes gradually increases towards the end of the partition. In addition, the same result can be obtained by reducing the thickness of the partition at the other end of the chamber, which is removed from the burner, so that as the distance from the burner 75 and the temperature of the flame washing the partition diminishes, the thickness of the partition decreases, making the transfer easier. heat through teregorodku and thus maintaining a uniform temperature in the buffer chamber. The walls of the mines 7 themselves may be slightly porous, and the walls 18 may tightly separate the combustion chambers. In which walls to make holes - in partitions, 7 or in walls 7 - depends on what kind of reducing agent is used - solid or gaseous, since in the first case the products of combustion can pass into the buffer chamber / 7, and in the second case the gases will pass from the mines into the buffer chambers, or vice versa, in which case reducing gases can be introduced through the buffer chambers.

Thus, instead of separating the material moving inside the shaft from the flame by the partition 18 alone, buffer chambers / 7 are used, located around and between the individual shafts 7, which together form one common restoring shaft, having a long and cross-sectional shape. narrow rectangle. This method makes it possible to obtain a relatively high reducing temperature in the center of the ore column, without having to maintain too high a temperature around the outer surface of the column. In other words, in the case of the reduction of iron ores, it is possible to maintain a constant temperature of 1050 ° in the buffer chambers / 7 surrounding the reducing at C, while the center of each ore column will hold a temperature of approximately 950 ° and at the same time, the reaction from endothermic reduction of FeO to Fe will occur. With this method of device, all tendency from the side of reduced iron to adhere to the walls of the shaft, as would be the case at temperatures above 1050 °, disappears, and thus free and continuous lowering of the ore column in each mine is ensured.

A somewhat modified device is characterized in that the individual shafts are composed of several pieces or pipes 20 connected to each other by corresponding butt joints 21. In this case, the buffer chambers 17 are arranged in the same way as in FIG. 1, wherein the walls of the tubular links 2 are partitions separating the buffer chambers 17 from the moving ore column (Figs. 7 and 8) ..

There are also fairly wide aisles 22 between the buffer chambers 17, so that, if desired, the buffer chambers separated from each other by horizontal partitions can be made mutually interconnected.

The pipes 20 may be made of metal or of a ceramic material. When attached to the buffer chambers in which the temperature is maintained within the above limits, the walls of the shafts can be metal throughout the entire height of each small shaft.

The new device is molded to a relatively high height. The preheating zone is designated 23, the recovery zone is 2- / and the cooling zone is -25. It is important not only to precisely control the temperature in each of the mines, but it is equally important to deliver enough heat to the required space. Thank you to increasing the surface of the mine in the heating zone and in the recovery zone and, moreover, due to the access of heat to the buffer chambers in An unlimited amount can, of course, be supplied, if desired, with a greater amount of heat and thus increase the speed of recovery and, consequently, the flow rate of caterial through each shaft (Fig. 9). ° In order to accomplish the aforementioned substantial acceleration of the process of restoring and material passing through, the shaft shown in FIG. 9 is composed of interconnected units or units, similar to the units shown in FIG. 7 and 8, and located along the length of the shaft like the device shown in FIG. The buffer chambers 17 are located on both sides of each row of pipes 20, and the heating chambers (combustion chambers) 11 are located along each buffer chamber, as in the device shown in FIG. 1, 2 and 7.

Burners inserted into the combustion chambers in each horizontal direction are located at opposite ends, for example, as shown in FIG. 2, of course, each set of burners belonging to any combustion chamber can be controlled independently, in order to accurately determine the temperature at various points along the height of the reducing zone, as well as to regulate the amount of heat to: this or that item.

By subdividing each common column of moving ore into several parallel pillars, attacks, and by arranging a buffer (equalizing temperature) chamber around the internal shafts, a large increase in surface area in the recovery zone and a smaller division of the ore layers in this zone are obtained, and as a result a greater amount of heat in order to carry out an endothermic reaction in the recovery zone, and to obtain a significant increase in the rate of movement of the material through the mines, and By increasing the height of the mines and using buffer chambers, it is possible to increase the reaction rate and the rate of advancement of the ore almost unlimitedly.

Such accelerated movement, of course, requires a significant increase in the amount of heat delivered, and accordingly, the need for more intensive heat absorption in the cooling zone appears. To this end, the inventor uses pre-cooling 26 (Fig. 9), where the coolant is predominantly liquid or liquid vapors and where the temperature of the reduced ore rapidly decreases from about 950 to 220 ° C, and second from 27 (Fig. 9), where the coolant is preferably cold air, which can be used for admission to the buffer chambers after it absorbs the heat of the descending ore and cools the latter from about 230 to 55 °.

The upper hole of the shaft (Fig. 9) should be left open, since due to the use of relatively small ore and fine reducing material, a rather hermetic plugging of the hole is obtained. The lower part of the shaft is provided with a sliding latch 28, which allows intermittently to discharge the restored; {ore) ore not allowing air to flow into the shaft. In the shaft (Fig. 9), the central gas vent is not shown, since it is self-evident that such a tube is not absolutely necessary in practice for the operation of the shaft. The shown central tube 9 (Fig. 2 and 5) may.

Of course, if desired, be used to introduce a gaseous reducing agent instead of draining through it the resulting

gases.

A buffer gas chamber / 7 is equally useful for both small and large installations, and is also suitable for ores of any grade and size; In all cases, the chamber / 7 functions in the same way, but the ability of the buffer chamber to supply an unlimited amount of heat at a predetermined temperature is especially useful when large furnaces are operated. The transmission rate of ore can increase almost infinitely, since no matter how many units of heat are needed to speed up the process, it is always possible to bring in the right amount of heat without resorting to an excessive increase in the temperature of the walls of the mine.

In addition, in connection with the described heat transfer method, the walls of the ore containing mines or the shafts that guide it can have almost any desired design, namely the ore can be surrounded by ceramic walls (Fig. 1), metal walls or pipes (Fig. 8) or may even be placed in metal boxes passed through a buffer-gas chamber 77 or chamber.

The subject of the patent.

Claims (2)

1. A device for the recovery of metal ores, consisting of a series of vertical shafts heated by heating chambers, characterized in that to balance the heat transferred to the shafts by the heating chambers, serve as buffer chambers 77 filled with a fixed gas located between the rows of shafts and heating chambers / 7 and interconnected passages. 2. The form of the apparatus according to claim 1, characterized in using in each shaft a pipe 9 (FIGS. 1, 2, 5 and 6) with intake openings 10 serving to remove the gas developing in the mine and at the same time for heating the inside mine. fig I Fig 6 to the patent of in-tsa V. G. Smith No. 30155 -and  - - /, fig 2 one , / I | -..- i  / 7 / 7 Well from f gz . d1 fig4 SSSSLSSx / f fig 5 fig 8 ; j .but t I Fig 9 .7, .. U u j