RU2228305C2 - Method of production of special kinds of clinkers and accompanying metals out of industrial wastes - Google Patents

Abstract

FIELD: metallurgy and chemical engineering. SUBSTANCE: the invention presents a method of production of special kinds of clinkers and accompanying metals out of industrial wastes. It is dealt with production of refractory metal and non-metallic materials, predominantly special kinds of the clinker having a high level of a melt viscosity and accompanying metals. The method may be used in metallurgy and chemical engineering. Technical result: usage of a flaming molten slag, decreased specific power inputs, utilization of industrial wastes, extraction of metals, substantial increase of quality of a produced product - clinker, considerable intensification of process of necessary minerals formation. The method of production of a special cement clinker and accompanying non-ferrous metals in a reactor with the plasma-arc and induction heating provides for feeding in the chamber of the reactor through its channels of a raw material mixture of chemical industry waste products containing non-ferrous metals, its heating up to temperature of 2100 C and melting-down with formation of the indicated cement clinker and its consequent cooling and selective extraction of non-ferrous metals at their melting-down by settling in the hearth part of the reactor and similar easily sublimated metals being condensed from vapors. The indicated industrial waste products of aluminate and-or silicate type and the indicated mixture additionally contain some chemical compounds of a faction up to 10 mm, providing at their smelting production of the indicated clinker. Heating is conducted within 1-10 minutes, and the chamber is additionally fed with waste products of the metallurgical production in the form of a flaming slag with a temperature of up to 1800 C. In the capacity of the industrial waste products they may use the waste catalysts. In the capacity of the indicated chemical compounds the lime fluxes and-or highly-aluminate materials may be used. Cool-down of the indicated clinker can be carried out by feeding of its melt having temperature of 1800 through a chute of the chamber onto the revolving around their axes in the counter directions in respect to each other and water-cooled from inside cylinders- granulators, allowing to control in time the process of cool-down of the melt of the indicated cement clinker to the given temperature 60 C. At that the rate of revolving and an amount of a cooling agent allow to keep a stable rate of cooling equal to 55 C/minute till the point of crystallization and to conduct the clinker cooling-down within 1-30 minutes, periodically converting its liquid phase into a solid one and vice versa, and forming at that the necessary minerals. EFFECT: the invention allows to use a flaming molten slag, to decrease specific power inputs, to utilize industrial wastes, to extract metals, to increase substantially the clinker quality and intensify the necessary minerals formation process. 4 cl, 3 tbl, 1 dwg

Description

The present invention relates to the production of refractory, metallic and non-metallic materials, mainly special types of clinker, having a high degree of melt viscosity and related metals.

A known method of producing cement clinker, comprising melting the raw mixture using an electric arc, in which the raw mixture is mixed with fractions of 0.05-20 mm with a moisture content of up to 2% at a temperature of 1600-1800 ° C for 0.1-30 minutes in neutral a gas environment or an environment with up to 8% oxygen content (RF patent No. 2040497, C 04 B 7/44 of 07/27/95, bull. No. 21).

The disadvantages of this method are as follows.

When implementing the method between the electrode-anode installed in the arch of the furnace, an electric arc is ignited, which melts the raw material fed into the bath, forming a conductive section in the thickness of the melt. The surface mirror of a fluid melt is limited to a value equal to two electrode diameters, i.e. heating of the material is localized and located in the thickness of the melt layer around a common vertical axis between unlike electrodes.

The productivity with this processing method, which depends, in particular, on the size of the melt pool, is limited, because in the peripheral zone of the bath, the viscous melt solidifies and does not pour out of the furnace. Forcing the arc power while stretching it vertically by moving (raising) the cathode leads to overheating of the walls and the arch of the furnace chamber, which, in turn, leads to fusion of the latter, an increase in heat loss to the environment, overheating and accelerated burnout of the graphite electrode-cathode.

In addition, melt mixing is also localized, which leads to a deterioration in the quality of the finished melt product, such as cement clinker. A temperature limited to 1800 ° C is insufficient to give a fluid state to many types of refractory materials with high melt viscosity, in particular Portland cement clinker with high saturation coefficients, which are decisive in obtaining a high-quality product.

A known method of extracting metals from metal-containing spent catalysts based on aluminum and (or) silicon oxides, including processing them when heated (RF patent No. 2075526 C1, 6 C 22 V 7/00 from 07/31/95, bull. No. 8).

The main disadvantages of this method are the inability to use waste from metallurgical industries both in the form of fiery liquid and in the form of granular slags, high energy consumption, low productivity.

The closest of the analogues is the method according to patent RU No. 2176277 of 11/27/2001

The claimed invention is aimed at solving the problem of the possibility of using metallurgical production wastes as fire-liquid slags, in the form of aluminate and (or) silicate spent catalysts of chemical industries as raw materials, the possibility of obtaining special types of artificial binders with the addition of calcareous fluxes from the above-mentioned technogenic wastes and (or) alumina materials, the possibility of obtaining non-ferrous metals from spent catalysts and industrial waste rows with their selective precipitation in the bottom phase, while expending only 30% of the energy required from an external source 100% of the electrical energy used for production of artificial binder (special cement clinker: high-alumina, aluminate, and Portland monophasic formulations) and associated non-ferrous metals.

This goal is achieved by the fact that in the method for producing a special cement clinker and associated non-ferrous metals in a reactor with plasma-arc and induction heating by supplying a raw material mixture containing technogenic waste from chemical plants containing non-ferrous metals to its chamber through its channels, it is heated to a temperature 2100 ° C and melting to obtain the specified cement clinker, followed by cooling, with selective extraction during melting of non-ferrous metals deposited in the hearth ctor, and condensed from vapors of easily sublimated metals, the indicated technogenic wastes are aluminate and / or silicate, and the specified mixture additionally contains chemical compounds of fraction up to 10 mm, which provide the specified clinker when melted, they are heated for 1-10 minutes, and the chamber additionally serves the waste of metallurgical production in the form of fire-liquid slag with a temperature of up to 1800 ° C.

Used man-made catalysts are used as industrial waste.

As these chemical compounds, lime fluxes and / or high aluminate materials are used.

In this method, in the production of special clinkers and non-ferrous metals, a plasma reactor (see drawing) is used, consisting of a metal casing 1, a special high-temperature lining 2, two graphite plasmatrons having a coaxial channel inside, located in the lid of the cathode 3 reactor and anode 4 with shelves and (or) a screw (on the drawing, shelves and auger are not conventionally shown) inside the plasma torch, four batchers 5 with slots 6 for introducing aluminate and (or) silicate spent catalysts 7 chemical plants containing color sintered metals mixed with calcareous fluxes and (or) high aluminate materials; as a result, a skull 8 is formed in the form of conical slopes corresponding to the side channels 9 located tangentially relative to the housing of the chamber 1 for introducing the waste of metallurgical industries in the form of liquid-liquid slag 10, an induction coil 11 for homogenizing the molten material, a copy path 12, two drain slots 13 , 14 for withdrawing clinker melts 15 and metal melts 16 from the reactor hearth from the hearth 17, rotating long cylinders internally cooled from the inside, rotating around their axis from each other (g anulyator) 18 for cooling special cement clinker 19.

The method is as follows.

From pre-crushed raw materials and catalysts containing non-ferrous metals (nickel, cobalt, tungsten, molybdenum, lithium, etc.) in a mixture with lime fluxes and (or) high-aluminate materials, raw mixes were prepared by mixing them (item 7) for addition to fire-liquid slag (item 10) - waste from metallurgical production for special types of cement clinkers.

The chemical compositions of slag - the waste of metallurgical production in the form of liquid-liquid slag, limestone, screenings of ore dressing - iron-containing additives, galvanic sludge, raw mixes and clinkers obtained by this method, are given in Table 1, 2.

Flame-liquid slag (10) - waste from metallurgical industries through the corresponding side channels 9, located tangentially relative to the chamber body, are added to aluminate and (or) silicate technogenic waste from chemical industries, for example spent catalysts (7) containing non-ferrous metals (nickel, cobalt , tungsten, molybdenum, etc.) in a mixture with lime fluxes and (or) high aluminate materials fractions up to 5 mm.

Raw mixtures, for example spent catalysts (7), are introduced into the chamber by side feeders 5 along the channel 6 located in the chamber walls, at an angle of 90 ° on one horizontal plane relative to each other. A raw material charge is fed to the upper part of the chamber above the melt surface to create a skull lining from the material itself at the boundary of the melt mirror, resulting in a skull 8 in the form of conical slopes, thereby eliminating thermochemical corrosion of the lining on the melt mirror. The melt contains in the calculated amount the chemical compounds listed in the above table, which provide artificial binders, for example cement clinker (item 19), when melted. When a certain mass of the melt is collected and the electrodes 3, 4 are heated inside the chamber above 1000 ° С, raw material is supplied through the cavities of the electrodes 3, 4 to the reactor chamber 1. At the same time, in the electrode 3, the raw material is transferred from the shelf to the shelf (not shown conventionally in the drawing of the shelf ), which are heated to a temperature close to the temperature of the electrode. With a relatively slow (compared to a vertical fall) movement of the material and direct contact with the heated surface of the shelves, heat is transferred from the shelves to the material, and the last (preheated), brought to the dissociation temperature of carbonates, enters the melt surface and melts at a higher speed, t .to. in this case, exothermal reactions are already taking place with heat evolution. The same process of heating the raw material occurs in the electrode 4, but in this case, heating occurs when the material moves along a helical surface.

Additional heat comes from the fire-liquid slag having a temperature of up to 1800 ° C. Schematically, the drawing shows the supply of metallurgical waste in the form of fire-liquid slag having a temperature of up to 1800 ° C, sharply reducing energy costs and increasing the productivity of the melting chamber and the quality of cement clinkers, and also shows the cooling of the melt of a special cement clinker with a temperature of up to 1800 ° C by feeding through the estrus 13 to long cylinders (granulator) 18, which are internally cooled from the inside, rotating on their axis in opposite directions from each other, 18. The channel is designated by 14, through which the molten metal is discharged. The deposition of metal is due to the fact that the latter has a 2 times higher density than molten clinker, the chemical composition of which is shown in table 1.

The melting process is carried out as follows (see drawing): the ends of the electrodes inside the chamber are brought down and lowered to the lower part of the chamber 1. When the raw material level is raised to the ends of the electrodes 3, 4, the latter is supplied with voltage, for example, direct current from the converter.

The ends of the electrodes are reduced to contact. When the electrodes are diluted, an electric arc discharge (arc) is formed, which is a low-temperature plasma. In this case, plasma-forming gas, for example nitrogen or carbon dioxide, is supplied to the electrodes. The material in the chamber is heated to its melting point. When firing clinker, the melt temperature reaches 2000-2100 ° C. When the melt rises above the coil 11, a voltage is applied to the latter, which causes the melt to rotate. Due to the copy path 12, the oscillatory motion of the coil 11 occurs. During the oscillatory movements of the coil 11, the magnetic field generated inside the conductive melt, which is actively mixed in the vertical plane and additionally heated, changes its position. As a result of mixing the melt, its homogenization occurs, which actively contributes to improving the quality and productivity of the main products, for example, cement clinker (19).

When melting the mixture to obtain a cement clinker, which contains a small amount of rare metals, some of them whose melting point is slightly higher than the clinker melt (except for tungsten and molybdenum) are deposited in the hearth 17 and periodically (as they accumulate) are released into the molds. The deposition of metals (16) is due to the fact that their density is at least two times higher than the clinker melt (15).

Vapors of easily sublimated non-ferrous metals (for example, lithium) together with carbon dioxide released as a result of decarbonization of the carbonate components of the clinker charge are evacuated by vacuum to special separation and conditioning devices, where metal vapors condense, passing into the metal or its compounds, and carbon dioxide It can be used to produce dry ice, or it is introduced into the reactor through special electrodes using a special supercharger. Light metals or their compounds are transferred for further processing to obtain a conditioned product. Clinker melt 15 is periodically or continuously (with a coordinated input of raw materials into chamber 1) poured onto long cylinders (granulator) 18, which are cooled from the inside, rotating around their axis in opposite directions from each other, allowing to control the process of cooling the melt of a special cement clinker 15 to a predetermined time temperature - 60 ° С.

We conducted physical and mechanical tests of cement clinker, the properties are shown in table 3. The cooled clinker is passed to the grinders to obtain cement.

Thus, the proposed method allows the use of fire-liquid slag and save specific energy consumption, utilize industrial waste (fire-liquid slag, spent catalysts, galvanic sludge), extract metals, significantly improve the quality of the resulting product, such as clinker, significantly intensify the process of formation of the necessary minerals .

If necessary, correcting iron-containing additives such as galvanic sludge, pyrite cinders, etc. can be added to the raw material mixture.

Depending on the composition of technogenic wastes and the composition of additionally introduced chemical compounds, various cement clinkers, such as high alumina, alumina, Portland and monophasic compositions, as well as related non-ferrous metals, can be obtained by this method.

Claims (4)

1. A method of producing a special cement clinker and associated non-ferrous metals in a reactor with plasma-arc and induction heating by feeding a raw material mixture containing technogenic waste from chemical plants containing non-ferrous metals to the reactor chamber through its channels by heating it to a temperature of 2100 ° C, and melting to obtain the specified cement clinker, followed by cooling, with selective extraction during melting of non-ferrous metals deposited in the hearth of the reactor and condensed from the vapor characterized by the fact that the specified technogenic waste is aluminate and / or silicate, and the specified mixture additionally contains chemical compounds of a fraction of up to 10 mm, which ensure the specified clinker during melting, they are heated for 1-10 minutes, and additionally serves metallurgical waste in the form of liquid-liquid slag with a temperature of up to 1800 ° C. 2. The method according to claim 1, characterized in that the spent catalysts are used as industrial waste. 3. The method according to claim 1 or 2, characterized in that as these chemical compounds use calcareous fluxes and / or high aluminate materials. 4. The method according to any one of claims 1 to 3, characterized in that the said clinker is cooled by supplying its melt with a temperature of 1800 ° C through the chute to the granulator cylinders that are water-cooled from the inside and rotate around their axis from each other, allowing control in time the process of cooling the melt of the specified cement clinker to a predetermined temperature of 60 ° C, while the rotation speed and the amount of cooling agent allows you to set the cooling rate equal to 55 ° C / min to the degree of crist llizatsii and to cool the clinker for 1-30 min, gradually turning its liquid phase into a solid, thereby forming the necessary minerals.