SU1223005A1 - Rotor furnace for roasting finely divided material - Google Patents

Description

The invention relates to a kiln device and can be applied in the production of firing fine materials, in particular flotation pyrites (FeS2), in order to obtain calcined gas containing sulfur dioxide (SO2).

The aim of the invention is to increase the intensity of burning of the flotation pyritic pyrite, reduce the remaining sulfur in the calcine and the dust content in the burning gas, reduce the cost of sulfuric anhydride.

FIG. 1 shows a rotary kiln, a section along the vertical axis; in fig. 2 - the upper and lower parts of the furnace on an enlarged scale; in fig. 3 shows section A-A in FIG. one.

The furnace consists of body 1 and liner 2, lined from the inside, flat ring 3, seam clamp 4, protrusion 5 with an edge, shaft 6, two stuffing seals 7, two rings 8, two threaded bushings with a flywheel 9 and two threaded bushings 10, continued which serves as the housing gland. There are two nozzles 11 (one of them is backup) and truncated cones 12 and 13 for loading into the furnace of the flotation sulfur pyrite.

Particles) is reported by a rotating cone 14 angular velocity and, due to it, they are for some time in a rotating, suspended state in the upper volume of the furnace, forming an intensely mixing flow, since in it solid particles and air have a high angular velocity. At sufficiently high rotor speeds, this flow is unconditionally turbulent. The turbulent 10 pulsations arising in this case mix the particles of a solid body in a gaseous medium in a stochoic manner, thus causing mutual diffusion. This is a great stimulus for the combustion reaction, and the I phase — thermal dissociation of nitrite, which occurs with the breaking off of one sulfur atom and burning its vapor with heat absorption, is fast-acting. But the angular velocity imparted to the two-phase flow has a finite effect and burning particles, having lost it, begin to descend along a damped spiral, but in this way they are again driven into rotational motion by a stream of secondary air leaving the nozzles 20 (number of nozzles along the height of the furnace not limited to) and vortex flow

20

with flanges, the cone 13 of ceramic 25 being spliced to the axis of the furnace, acquiring a weighted, refractory. A cone 14 is mounted on the shaft to communicate the rotational movement of the flotation sulfur pyrite. On the ledge, in its slots, are installed the inner 15 and outer 16 fire-resistant pipes. Air is supplied to the furnace to oxidize and self-ignite the flotation sulfur pyrite, and also to cool the rotor, the electromagnetic converter 17, the boundary gas layer and the pyrite calcination particles at the outer surface of the pipe 16 through air pipes 18 and 9, and secondary air is supplied through the nozzles 20. The burning gas is removed through the pipe 21, and the calcine through the outlet 22. The electric current is transmitted to the electromagnetic converter via the cable 23. To reduce the temperature in the furnace The manure 24 (supply of refrigerant thereto is not shown in Fig. 1) and cooling elements 25. The refrigerant is supplied by the feed mechanism 26. The furnace is mounted on the base 27.

The process of firing fine materials, in particular flotation sulfur pyrites, in a furnace is carried out as follows.

After the furnace is heated up to not less than 500 ° C, the shaft 6 is rotated, which does not come in contact with the lining, but only with the packing seals 7, then the flotation sulfur pyrite enters the cone 14 and simultaneously under it, under the cone 14 air is supplied through air pipes 18 and 19 and further along refractory pipes 15 and 16. At the same time, the components of a two-phase flow (air and solid

rotational motion. In this vortex flow, the intensification of the combustion of particles continues with the release of heat, which ends with the completion of the third phase of the combustion reaction in a suspended, rotating

30 states. The calcine flow revolving around pipe 16 eventually begins to settle and in this way is attracted to the bottom of pipe 16 by a changing magnetic field created by an electromagnetic transducer 17 along the poles. When changing the pole of the magnetic field, the candle ends and collapses along the forming asymmetrically conical part of the body furnace, directed to the exit of the furnace through the hole 22.

Roasting gas with a minimum dust content is removed from the furnace through nozzle 21. It is possible to reduce the temperature in the furnace when required by passing the cooled air through the pocket 24 and the refrigerant through the cooling

 5 elements 25. The number of turns of the cooling elements is not limited, they can be completely eliminated, if it is found that to reduce the temperature in the furnace, the passage of air through pipes 15 and 16 is sufficient, the passage of cooled air through the pocket 24 and candle end when leaving the furnace contains little sulfur.

40

50

The temperature in the upper part of the furnace is 600-700 ° C, and in the lower part it is 800-900 ° C. In this 55 CONNECTION, the cone 14, the truncated cone 12 and the nozzles 20 are expediently made of sheet steel that withstands temperatures in the working position of 1100-1-1200 ° C, and the shaft 6 is made of long products (round bars) and the rotating cone 14 angular speed and thanks to it, they are for some time in a rotating, suspended state in the upper volume of the furnace, forming an intensely mixing flow, since in it solid particles and air have a high angular velocity. At sufficiently high rotor speeds, this flow is unconditionally turbulent. The turbulent pulsations arising in this case mix the solid particles in a gaseous medium in a stochoic manner, thus causing mutual diffusion. This is a great stimulus for the combustion reaction, and the I phase — thermal dissociation of nitrite, which occurs with the breaking off of one sulfur atom and burning its vapor with heat absorption, is fast-acting. But the angular velocity imparted to the two-phase flow has a finite effect and burning particles, having lost it, begin to descend along a damped spiral, but in this way they are again driven into rotational motion by a stream of secondary air leaving the nozzles 20 (number of nozzles along the height of the furnace not limited) and swirling flow

5 bolted to the axis of the furnace, acquiring a weighted 5

rotational motion. In this vortex flow, the intensification of the combustion of particles continues with the release of heat, which ends with the completion of the third phase of the combustion reaction in a suspended, rotating

0 state. The calcine flow revolving around pipe 16 eventually begins to settle and in this way is attracted to the bottom of pipe 16 by a changing magnetic field created by an electromagnetic transducer 17 along the poles. When changing the pole of the magnetic field, the candle ends and collapses along the forming asymmetrically conical part of the body furnace, directed to the exit of the furnace through the hole 22.

Roasting gas with a minimum dust content is removed from the furnace through nozzle 21. It is possible to reduce the temperature in the furnace when required by passing the cooled air through the pocket 24 and the refrigerant through the cooling

 5 elements 25. The number of turns of the cooling elements is not limited, they can be completely eliminated, if it is found that to reduce the temperature in the furnace, the passage of air through pipes 15 and 16 is sufficient, the passage of cooled air through the pocket 24 and candle end when leaving the furnace contains little sulfur.

0

50

The temperature in the upper part of the furnace is 600-700 ° C, and in the lower part it is 800-900 ° C. In this CONNECTION, the cone 14, the truncated cone 12 and the nozzles 20 are expediently made of sheet steel, which withstands the temperature in the working position of 1100-1-100 ° C, and the shaft 6 - of rolled sections (rods of circular section), used for the manufacture of gas turbine blades . Their strength remains high up to 800-900 ° C.

The furnace consumes less than 50 W of electric power per rotor t / h on the rotor shaft, allows to intensify the burning process of the flotation pyritic pyrite and reduce the content of sulfur residue in the calcine, as well as reduce the dust content in the output

Z

roasting gas and thereby reducing the consumption of electricity consumed by the electrostatic precipitator during the purification of roasting gas. The furnace has inertia, since the residence time of particles in a suspended, vrash, and a state inside the furnace is relatively long compared with the residence time of particles during linear motion in a known furnace.

6

fig 1

9 I-

FIG. 2

Claims (1)

ROTARY FURNACE FOR FIRING FINE DISPOSAL MATERIAL, containing inside lined cylindrical body, loading device, primary and secondary air supply pipes, flue gas discharge pipe, unloading and cooling device, characterized in that, in order to increase the intensity of firing of flotation sulfur pyrites, reducing the residue in the cinder and the dust content in the calcining gas, reducing the cost of sulfur dioxide, it is equipped with a rotating shaft mounted along the axis of the housing with a fixed on it a cone, a liner placed in the arch of the furnace with a hole for the shaft, and an electromagnetic transducer, while the lower part of the housing is made asymmetrically-conical with a protrusion located along the axis of the furnace, and the protrusion is made with holes for the shaft and for the primary air supply pipes and grooves in which the refractory pipes are installed, in addition, the secondary air supply pipes are installed tangentially, the loading device is made in the form of two concentric truncated cones and at least one pipe on above, and one § the end of each primary air supply pipe is made in the form of an open ring with holes located on the protrusion, the electromagnetic converter is also located on the protrusion, and the cooling device is in the lower part of the furnace body.