RU2413011C1 - Plasma-chemical reactor for processing mineral ore - Google Patents

Abstract

FIELD: metallurgy. ^ SUBSTANCE: plasma-chemical reactor for processing mineral ore consists of case, of device for plasma generation, of device for supply of gas and ore,and of device for withdrawal of processed ore and gas. Also, inside the case there is made a vertical partition forming a gap between a lower edge of the partition and a bottom of the reactor case. The device for withdrawal of processed ore is made in a lower part of the reactor, while the device for withdrawal of gas is made as a connecting pipe installed in an upper part of the reactor case formed with the vertical partition and a wall of the reactor case. ^ EFFECT: raised efficiency of process in reactor. ^ 1 dwg

Description

The invention relates to a device for a plasma chemical reactor designed for high-temperature processing of mineral ores before flotation, and can be used in the hardware design of processes of recovery from metal oxides (molybdenum, lead, tin) of pure metals and the release of sulfide minerals from sulfur.

In the patent RU No. 2247154 (IPC ⁷ C21B 13/02, publ. 02.27.2005) a reactor is described equipped with a device for loading material under the action of gravity. At the top of this reactor is a reaction zone in which a reduction reaction takes place. The reactor also comprises means for introducing feed material through the neck of the reactor, means for introducing a gas stream, means for discharging the reduced material from the bottom of the reactor, and means for discharging exhaust gases. The reactor includes an upper zone of heating, pre-reduction and final reduction having a conical downward divergence, and a second, lower carbonization and cooling zone having a conical downward convergence.

The technical result consists in increasing the efficiency of the process carried out in the reactor.

Common with the proposed reactor design is a vessel, means for introducing feed material, means for introducing a gas stream, means for discharging reduced material.

The design of this reactor does not allow for the efficient separation of gas and solid material directly in the reactor vessel.

From the patent RU No. 2138929 (IPC ⁶ H05H 1/24, H05B 7/16, publ. 09/27/1999) a plasma-chemical reactor is known which contains a plasmatron, nozzles for dispersing the solution, a reaction chamber and a nozzle for removing the vapor-gas mixture connected to its lower end. The pipe is placed at an angle of 130-140 ° C to the reaction chamber. The transition from the reaction chamber to the outlet pipe of the dust-gas mixture is made in the form of a knee, and after the knee, a container for collecting substandard powder is installed.

The implementation of this plasma chemical reactor allows you to increase productivity by 10 times, reduce the amount of substandard powder from 25-30 to 0.1-0.3%, increase inter-stop mileage from 0.5-1.0 days to 10 days or more.

In common with the proposed reactor design is a vessel, a plasma generation device (plasma torch), a solution (nozzle) for supplying a solution, a product output device.

The disadvantage is similar to the previous analogue.

The patent SU No. 904223 (IPC ⁶ B01J 1/08, publ. 07.20.1999) also describes a plasma-chemical reactor containing a housing, a cooled reaction chamber installed in the housing, plasmatrons, a gas quenching device placed in the reaction chamber and made in the form of a supersonic nozzle , and plasma nozzles connecting the plasma torches with a gas quenching device.

The supersonic nozzle is made in the form of two hollow disks coaxially mounted with the possibility of mutual displacement opposite each other, the working surfaces of which are made in the form of bodies of revolution with curvilinear generators, and in one of the disks a central hole is made connected to the plasma-leading nozzle. The working surface of the second disk is made of flexible heat-resistant material and a central hole is made in it, connected to the plasma-leading pipe.

The aim of the invention is to intensify the process and increase productivity.

Common features with the proposed reactor design is the presence of a vessel, a plasma generation device.

The disadvantage is similar to the previous analogue.

The closest (prototype) is the plasma chemical reactor described in [A.L. Suris. Plasma-chemical processes and devices. Chemistry Publishing House, 1989, pp. 8-10.].

Known plasma-chemical reactor consists of a cathode, insulator, anode, mixing device, reaction channel, quenching device, heat exchanger, filter. An electric arc is formed between a cathode made of a refractory material and a water-cooled copper anode made in the form of a nozzle. Plasma-forming gas (air, hydrogen) is selected depending on the type of process being carried out (heat treatment of ore before flotation, reduction of metal oxides). Passing through the discharge zone, the gas is heated, ionized, and flows into the reactor in the form of a plasma jet with a mass-average temperature of 2000-10000 K. The jet enters the mixing chamber of the reactor, where raw materials are introduced into it. In the reaction channel there is a chemical interaction of the reactants with the formation of the target products. The walls of the reactor are cooled by water. The quenching device and heat exchanger are designed to cool the reaction products. The filter separates gases from solid particles. A gas and dust mixture flows from the reactor to the heat exchanger at high speed.

The disadvantages of the prototype are increased gaseous erosion of the walls of the tubes of the heat exchanger, resulting in increased operating costs. In addition, this reactor is characterized by an unreasonably long contact time between high-temperature gas and the processed material (up to 5 s), which leads to a decrease in reactor productivity and a deterioration in the quality of processing of raw materials (lead and tin melting).

The objective of the invention is to expand the arsenal of plasma chemical reactors designed for high-temperature processing of mineral ores before flotation.

The technical result of the invention is:

- increasing the productivity of the plasma chemical reactor for ore, while improving the quality of the product;

- reduction of capital and operating costs for cooling products in the heat exchanger;

- reducing the contact time of high temperature gas and the processed material;

- reduction of ore losses with exhaust gases.

The elimination of these drawbacks and the achievement of the claimed technical result from the implementation of a plasma-chemical reactor for processing mineral ores containing a casing, a plasma generation device, a gas and ore supply device, and an output device for processed ore and gas are achieved due to the fact that a vertical partition is made inside the reactor casing with the formation of a gap between the lower edge of the septum and the bottom of the reactor vessel, a device for outputting the processed ore is made in the lower part of the reactor, and a device for Displayed gas formed as a spout mounted on the top of the reactor vessel formed by a vertical partition and the wall of the reactor vessel.

A comparative analysis of the prototype and the claimed invention shows that the common structural features are a housing, a plasma generation device, a gas and ore supply device, a processed ore and gas output device.

A distinctive feature of the claimed invention is that a vertical partition is made inside the reactor vessel with the formation of a gap between the lower edge of the partition and the bottom of the reactor vessel, the device for outputting the processed ore is made in the lower part of the reactor, and the device for gas output is made in the form of a fitting installed in the upper parts of the reactor vessel formed by a vertical partition and the wall of the reactor vessel.

The essence of the proposed reactor is illustrated in the drawing, which schematically shows the reactor, the plasmatron and the tank for wet gas purification.

The reactor contains a housing 1, a cover 2, a pipe 3, a coupling 4, a plasma torch 5, a gas supply device, a loading funnel 6, a protective shield 7, a device for unloading the processed product 8, a device 9 (bubbler) for supplying gas to a tank of water 11, vertical a flat partition 10, a container of water 11, a device 12 (fitting) for removing gas from the reactor.

The inventive plasma chemical reactor is a cylindrical tank (height 1400 mm and a diameter of 400 mm) with a conical bottom. The reactor vessel 1 is made in the form of a steel sheet metal structure lined from the inside, all the components and mechanisms of the reactor are mounted on it. In the upper cover 2 of the housing 1, a pipe 3 is welded with a thread on the end. A coupling 4 is screwed onto the threaded part of the pipe, into which the plasmatron 5 is inserted. By rotating the coupling 4, the intermediate clearance between the plasma flame and the opening of the loading funnel 6, through which ore or concentrate is filled, is adjusted. The walls of the housing are protected by a lining. The shield 7 is designed to protect service personnel from the action of high temperature during the removal of the plasma torch head from the pipe 3. Through the device 8, the processed product is discharged, and gas is removed from the reactor through the device 12 (fitting). The inventive reactor (see drawing) also provides for cooling the walls of the vessel with water.

The proposed plasma-chemical reactor is manufactured at an existing plant and operates as follows.

The ore productivity of this reactor is 53 t / h. Plasma-forming gas (air, hydrogen) is selected depending on the type of process being carried out (heat treatment of ore before flotation, reduction of metal oxides). After supplying electric energy, water, gas and the readiness of the system, ignition of the plasma torch 5 is turned on. The average temperature of the medium in the reactor is 5800-6000 ° С. Clutch 4 using a thread on the pipe 3 regulate the position of the flame in the reaction zone. Thus, the material loaded into the funnel 6 can be fed into various sections of the flame. During the operation of the reactor in the vessel create excess pressure (2.5 · 10 ⁵ PA). In order to prevent ore losses, a water trap with a bubbler 9 is installed.

To reduce turbulence and to separate gas from solid particles due to inertia, a vertical baffle 10, which is a porous metal fabric or porous ceramic, is welded in the reactor vessel 1. Between the lower edge of the partition 10 and the bottom of the housing, a gap is formed, which ensures the passage of gas.

Solid particles settle in the conical bottom of the reactor by changing the direction of gas flow by 180 °. The purified (partially) gas goes around the partition 10 and enters the space between the partition 10 and the wall of the housing, from where it enters the bubbler 9 through the nozzle 12 and then into the water tank 11. Some part of the ore in the form of dust rises up between the gas the wall of the tank and the partition 10, then through the bubbler 9 of the hydraulic lock it enters the tank with water 11, where the particles are deposited and sent to flotation, and the cooled gas is cleaned into a cyclone. This eliminates the loss of ore with escaping dust. Wet method of gas purification from particles, carried out in the tank 11, is more effective than that used in the prototype dry cleaning method.

From tank 11, water with solid particles enters the flotation. Solid particles from the lower conical part of the reactor vessel (see drawing) also go to cooling and then to flotation. The removal of processing products is carried out through the unloading device 8.

Due to the separation of gas and solid particles directly in the reactor vessel, the contact time of the ore particle with the plasma stream in the new reactor compared with the prototype reactor is reduced from 1-5 s to 0.1-0.5 s. The latter allows you to increase the productivity of the reactor in ore by almost 20-30%, and the quality of ore processing is improved.

Prevention of increased wear of the walls of the tubes of the heat exchanger is also achieved by the separation of gas and solid particles directly in the reactor vessel, and not after the heat exchanger, as in the known construction.

Thus, in the proposed plasma chemical reactor creates more favorable conditions for the process than in the reactor of the prototype.

Claims (1)

Plasma-chemical reactor for processing mineral ores, comprising a vessel, a plasma generation device, a gas and ore supply device, a processed ore and gas output device, characterized in that a vertical partition is made inside the reactor vessel to form a gap between the lower edge of the partition and the bottom of the reactor vessel, device for the output of the processed ore is made in the lower part of the reactor, and the device for the output of gas is made in the form of a fitting installed in the upper part of the reactor vessel, formed vertically linen partition and the wall of the reactor vessel.

Images