CN212673858U - Device for preventing flue gas pipeline of ferronickel ore smelting furnace from bonding - Google Patents

Abstract

The utility model discloses a device for preventing flue gas pipeline of a ferronickel ore thermal furnace from bonding, which is provided with a furnace body, wherein a buffering smoke exhaust cavity is embedded in the top part of the furnace body in half, and an oxygen supply pipeline is arranged around the middle part of the furnace body; the outer diameter of the buffer smoke exhaust cavity is gradually increased along the direction far away from the top of the furnace body. The technical scheme of the utility model, through reasonable calculation and design, remove most smoke and dust to the greatest extent, reduce follow-up indirect heating equipment's dust removal burden, reduce indirect heating equipment's an investment.

Description

Device for preventing flue gas pipeline of ferronickel ore smelting furnace from bonding

Technical Field

The utility model belongs to flue gas heat recovery field, concretely relates to prevent hot stove flue gas pipeline of ferronickel from bonding device.

Background

At present, the RKEF (rotary kiln and submerged arc furnace) is a main process for smelting high-grade molten nickel iron, and the semi-closed submerged arc furnace is a core device of the RKEF process (the invention takes the semi-closed submerged arc furnace as a research object). The heat source of the semi-closed ferronickel ore heating furnace mainly comes from electric energy, and part of the heat source comes from sensible heat brought by high-temperature nickel iron ore and chemical heat emitted by excessive coal powder serving as a reducing agent in the furnace. In the smelting process of the semi-closed submerged arc furnace, a large amount of high-temperature dust-containing smoke is generated in the furnace, the smoke contains 40-60% of CO, when the high-temperature smoke rises to a furnace opening part, the smoke is mixed into the high-temperature smoke to generate secondary combustion, the temperature reaches 700-900 ℃ (up to 1200 ℃ when the furnace condition is abnormal), and the smoke and dust are carried. When the smoke at the top of the furnace passes through the smoke pipeline in a negative pressure mode, the smoke burns again due to air leakage, so that a large amount of smoke dust and granules are melted and bonded on the pipe wall, and finally the pipeline is blocked, the whole production line is forced to be stopped, and the smoke needs to be manually cleaned. If high-dust flue gas with unburned CO enters the heat exchange equipment after passing through the heat insulation flue, secondary combustion is bound to occur, and melts are adhered to the outer wall of the heat exchange pipe, so that the heat exchange efficiency is reduced. Therefore, an efficient dust removal facility is arranged near the submerged arc furnace to purify high-temperature flue gas and burn off CO, so that the blockage of a subsequent flue gas pipeline is avoided, and the efficiency of heat exchange equipment is improved.

In the actual production, the following scheme is mainly adopted to slow down or prevent the blockage of the flue gas pipeline of the submerged arc furnace:

scheme 1: a plurality of air leakage ports are arranged along the flue gas pipeline of the submerged arc furnace so as to quickly burn off CO in the flue gas, cut off a heat source for melting smoke dust and avoid pipeline adhesion; the subsequent heat exchange equipment is provided, and anti-adhesion and ash removal measures are considered in the form of the heat exchange equipment; the disadvantage is that a plurality of air leakage openings are arranged on the heat insulation pipeline along the way, and the air quantity mixed into the flue gas cannot be adjusted. If excessive air is mixed, the temperature of the flue gas is too low, and the recovery rate of the waste heat of the flue gas is reduced; the smoke is burnt in the narrow space of the heat insulation pipeline, and the pipeline blockage is caused. The heat exchange equipment arranged behind the scheme still needs to consider measures of dust removal and ash removal, so that the primary investment of the boiler is increased;

scheme 2: a settling chamber is arranged near a fire hole smoke pipe of the submerged arc furnace, the chamber is a large cavity so as to prolong the retention time of smoke, dust naturally settles at a cone end and is periodically discharged through a lower gate valve. The subsequent heat exchange equipment is arranged, and anti-adhesion and ash removal measures are considered in the form of the heat exchange equipment. Scheme 2 is improved compared with 1, sets up the deposit room near hot stove in the ore deposit, collects a large amount of smoke and dust in this room, has reduced follow-up jam source. However, the scheme does not set an air mixing point with adjustable flow, so that the residual CO cannot be completely combusted, and in addition, most chambers are additionally arranged on the site by production units, the design is rough, no calculation basis exists, the dust removal efficiency is low, and the problem of pipeline blockage is not solved. The scheme is provided with heat exchange equipment, and dust removal and ash removal measures still need to be considered, so that the one-time investment of the boiler is increased.

Disclosure of Invention

To the defect among the prior art with not enough, the utility model aims at providing a prevent hot stove flue gas pipeline bonding device of ferronickel ore will be partly airtight hot stove flue gas of ferronickel ore in remaining CO burn out in big cavity to be equipped with flow adjustable air and sneak into the device, avoid sneaking into excess air and reduce the gas temperature, improve waste heat recovery rate.

In order to achieve the purpose, the utility model adopts the technical proposal that:

a device for preventing flue gas pipeline of a ferronickel ore heating furnace from being bonded is provided with a furnace body, a buffering smoke exhaust cavity is embedded in the top half of the furnace body, and an oxygen supply pipeline is communicated and surrounded outside the middle part of the furnace body; the outer diameter of the buffer smoke exhaust cavity is gradually increased along the direction far away from the top of the furnace body.

Optionally, the buffer smoke exhaust cavity is provided with a cavity tube, and a buffer smoke exhaust tube is communicated with the cavity tube; the buffering smoke exhaust pipe is of a pipe body structure with gradually enlarged outer diameter.

Optionally, the height of the buffering smoke exhaust pipe is 1/3-3/4 times of the height of the furnace body.

Optionally, the range of the outer diameter of the buffering smoke exhaust pipe is 1.5-2.5 m.

Optionally, the depth of the buffer smoke exhaust cavity embedded into the furnace body is 1-2 m.

Optionally, an annular gap is formed between the buffer smoke exhaust cavity and the furnace body, and the volume of the annular gap is 80-90 m³。

Optionally, the oxygen supply pipeline comprises an oxygen supply main pipe and a plurality of oxygen supply branch pipes; the oxygen supply branch pipes are communicated along the circumferential direction and are arranged around the outside of the furnace body.

Optionally, the furnace body is sequentially provided with a smoke inlet section, a buffer combustion section and a sedimentation ash discharge section along the axial direction; the buffering smoke discharging cavity is embedded along the smoke inlet section and the buffering combustion section; the oxygen supply pipeline is arranged around the buffer combustion section.

Optionally, the smoke inlet section is of a conical cavity structure, and a smoke inlet pipe is communicated with the smoke inlet section; and a smoke exhaust pipe is communicated with the top of the buffer smoke exhaust cavity, and a CO detector is arranged on the smoke exhaust pipe.

Optionally, the sedimentation ash discharge section is of a conical cavity structure, and an ash discharge valve is arranged at the bottom of the sedimentation ash discharge section; and an access hole is formed in the side wall of the sedimentation ash discharge section.

The technical scheme of the utility model, through reasonable calculation and design, remove most smoke and dust to the greatest extent, reduce follow-up indirect heating equipment's dust removal burden, reduce indirect heating equipment's an investment.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

FIG. 1 is a schematic structural view of the device for preventing the flue gas pipeline of the ferronickel ore hot furnace from bonding;

the reference numerals in the figures denote: 1-buffer smoke exhaust cavity, 11-buffer smoke exhaust pipe, 2-furnace body, 21-smoke inlet section, 22-buffer combustion section, 23-sedimentation ash discharge section, 231-overhaul port, 3-oxygen supply main pipe, 31-oxygen supply branch pipe, 4-smoke inlet pipe, 5-smoke exhaust pipe and 51-CO detector;

a-oxygen supply main pipe valve, b-oxygen supply branch pipe valve and c-ash discharge valve.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

In the present disclosure, the term "axial direction" refers to the axial direction of the intermediate shaft assembly or the two-shaft assembly, and the terms "upper", "lower", "left" and "right" in the present disclosure are based on the orientation in the drawings, and the terms "top", "bottom" and "side" are the upper, the lower and the periphery in the drawings are the "bottom" and the periphery is the "side", and the above description applies to all the contents of the present disclosure unless otherwise specified.

With reference to fig. 1, the device for preventing flue gas pipeline adhesion of a ferronickel ore thermal furnace of the present disclosure is provided with a furnace body 2, a buffering smoke exhaust cavity 1 is embedded in the top half of the furnace body 2, and an oxygen supply pipeline is communicated and surrounded outside the middle part of the furnace body 2; the outer diameter of the buffering smoke exhaust cavity 1 is gradually enlarged along the top far away from the furnace body 2. The device disclosed by the invention can remove most of smoke dust in the flue gas of the semi-closed ferronickel ore heating furnace, and simultaneously burn off residual CO in the flue gas, thereby avoiding the blockage of a flue gas pipeline, saving a dust removal and ash removal facility of subsequent heat exchange equipment and reducing one-time investment; the structure form (inner and outer sleeve type) of the device; the straight section of the outer sleeve is provided with a plurality of layers of compressed air circular pipes, and a plurality of branch pipes are arranged in the circumferential direction and inserted into the straight section to mix air; every layer of ring canal sets up electrical control valve, according to flue gas temperature, CO content dynamic adjustment regulation sneak air volume, sets up sneak air adjustable device, guarantees CO burnout in the flue gas, avoids sneaking into excessive air and reduces the flue gas temperature simultaneously to improve flue gas waste heat recovery rate.

In the embodiment of the disclosure, the buffer smoke exhaust cavity 1 is provided with a cavity tube, and a buffer smoke exhaust tube 11 is communicated with the cavity tube; the buffering smoke exhaust pipe 11 is a pipe body structure with gradually enlarged outer diameter. The structure of the buffering smoke exhaust pipe 11 ensures that the flow velocity of the smoke is gradually increased on the premise of ensuring enough smoke running space.

In the embodiment of the disclosure, the height of the buffering smoke exhaust pipe 11 is 1/3-3/4 times of the height of the furnace body 2, for example, when the height of the conventional furnace body 2 is 4m, the height of the buffering smoke exhaust pipe 11 can be 1.3-3 m. The height setting of buffering exhaust pipe 11 guarantees that the flue gas velocity of flow crescent when can sink the end and subside the smoke and dust, is discharged by the pipe 5 of discharging fume at top, realizes high-efficient rapid processing.

In the embodiment of the disclosure, the outer diameter range of the buffering smoke exhaust pipe 11 is 1.5-2.5 m, preferably 2-2.5 m, and the buffering smoke exhaust pipe is tapered and gradually increased, and preferably, the maximum outer diameter of the buffering smoke exhaust pipe 11 is at least half of the outer diameter of the furnace body 2, so that sufficient operation space is ensured after smoke enters, and smoke is discharged after settlement is realized.

In the embodiment of the disclosure, the depth of the buffer smoke exhaust cavity 1 embedded into the furnace body 2 is 1-2 m, preferably 1.5m, that is, the depth of the buffer smoke exhaust cavity 1 embedded into the furnace body 2 is at least 1/2-3/4 times of the height of the furnace body, so as to ensure that the buffer smoke exhaust cavity 1 and the furnace body 2 form a sufficient annular gap, and simultaneously, the buffer smoke exhaust cavity can have a sufficient height to discharge smoke.

In the embodiment of the disclosure, an annular gap is formed between the buffering smoke exhaust cavity 1 and the furnace body 2, and the volume of the annular gap is 80-90 m³Preferably 85m³The smoke can stay in the device for enough time, and the smoke dust can be settled.

In the embodiment of the present disclosure, the oxygen supply line includes an oxygen supply main pipe 3 and a plurality of oxygen supply branch pipes 31; the oxygen supply branch pipes 31 are circumferentially communicated and enclosed outside the furnace body 2. So that the air is uniformly distributed along the radial direction of the device and the participation of CO in full combustion is ensured.

In the embodiment of the present disclosure, the furnace body 2 is provided with a smoke inlet section 21, a buffer combustion section 22 and a settling ash discharge section 23 in sequence along the axial direction; the buffering smoke discharging cavity 1 is embedded along the smoke inlet section 21 and the buffering combustion section 22; the oxygen supply pipeline is arranged around the buffer combustion section 22. Be provided with the oxygen suppliment on the oxygen suppliment is responsible for 3 and the oxygen suppliment branch pipe 31 and be responsible for valve a and oxygen suppliment branch pipe valve b, the valve can be electric butterfly valve, can adjust the air flow rate that gets into in the buffering burning section 22 at any time through the setting of above-mentioned valve, and then control CO's combustion degree, should guarantee that CO burns out, can not introduce too much low temperature air simultaneously to avoid influencing subsequent flue gas waste heat's recovery, realize the balance between dust removal and the flue gas waste heat recovery relation.

In the embodiment of the present disclosure, the smoke inlet section 21 is a tapered cavity structure, and the smoke inlet pipe 4 is arranged in the smoke inlet section 21 in a communicating manner, preferably in a communicating manner along a lateral direction; and a smoke exhaust pipe 5 is communicated with the top of the buffer smoke exhaust cavity 1, preferably arranged in the lateral direction, and a CO detector 51 is arranged on the smoke exhaust pipe 5 for detecting whether CO is completely combusted so as to adjust the oxygen supply amount.

In the embodiment of the present disclosure, the sedimentation ash discharge section 23 is a conical cavity structure, and an ash discharge valve c is arranged at the bottom of the sedimentation ash discharge section 23; an access hole 231 is arranged on the side wall of the sedimentation ash discharge section 23. In the case of long-term or multiple operation of the device, if the sedimentation ash discharge section 23 is blocked, the cleaning can be manually carried out.

In the production process of the semi-closed ferronickel ore heating furnace, firstly, primary furnace gas is generated in the furnace, the furnace gas still contains a large amount of CO when reaching a furnace mouth part, and because the furnace mouth part is in a semi-open type, a large amount of air meets the furnace gas and then is violently combusted, so that high-temperature dust-containing smoke (the temperature is 700-900 ℃, and the dust content is 35g/NM3) is generated. The high-temperature dusty flue gas enters the anti-bonding device of the present disclosure through the smoke inlet pipe 4. When the flue gas passes through the device at a low speed (2m/s), smoke dust in the flue gas fully settles in the gaps between the inner sleeve and the outer sleeve due to inertia, residual CO is fully combusted (an oxygen supply pipeline is mixed with a proper amount of compressed air), the purified flue gas continuously enters the buffering smoke exhaust cavity 1 and leaves the device, and finally the purified flue gas is sent to subsequent heat exchange equipment through the smoke exhaust pipe 5 to complete the recovery of the flue gas waste heat.

FIG. 1 shows that the anti-sticking device of the present invention is a sleeve type structure, the inner cylinder is in a shape of a "horn" mouth (made of Q235-B), i.e. the buffer smoke exhaust cavity 1, and the inner side and the outer side are both provided with heat insulation spray paint; the outer sleeve is a furnace body 2, which is divided into an upper conical section, a straight section and a lower conical section, namely a smoke inlet section 21, a buffer combustion section 22 and a sedimentation ash discharge section 23 in sequence, wherein the inner side of the outer sleeve is provided with a heat insulation spray coating, and meanwhile, the straight section of the outer sleeve is provided with 2 layers of oxygen supply branch pipes 31 (the number of ring pipes can be increased according to the size of the device, each layer of ring pipe inlet section is provided with an electric butterfly valve for adjusting the mixed air amount), and the circumferential direction of the ring pipe is provided with a plurality of branch pipes which are inserted into the straight section; the lower cone end of the outer cylinder is provided with an ash discharge pipe, the accumulated ash of the cone section is periodically discharged through an ash discharge valve c, and the cone section is provided with an access hole 231. The opening of the oxygen supply branch pipe valve b (electric butterfly valve) on each layer of oxygen supply branch pipe 31 is adjusted according to the temperature and the parameters fed back by the CO detector 51, so as to avoid the excessive air and reduce the smoke temperature while ensuring the CO to be burnt out.

Take a 33MW semi-closed ferronickel ore furnace as an example, produce nickel and paste water 230t/d daily, if once monthly blocks up, once clearance time needs 10h, needs 6 manual works at every turn, a crane machine class, then the pipeline that once clears up needs the expense to be: 1000 (profit per ton ferronickel) 230 (10/24) +6 (labor cost) + 180 (crane platform shift cost) 98913 yuan, and the cleaning cost can be saved by about 120 ten thousand yuan in one year; if the subsequent heat exchange equipment omits a dust removal and ash removal facility and can reduce the weight by 10t, the one-time investment is saved by 20 ten thousand yuan; the device can reduce the washing of the heat exchange equipment by smoke and dust and prolong the service life of the heat exchange equipment.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims (10)

1. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded is characterized by comprising a furnace body (2), wherein a buffering smoke exhaust cavity (1) is embedded in the top half part of the furnace body (2), and an oxygen supply pipeline is communicated and surrounded outside the middle part of the furnace body (2);

the outer diameter of the buffering smoke exhaust cavity (1) is gradually increased along the top far away from the furnace body (2).

2. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded is characterized in that the buffering smoke exhaust cavity (1) is provided with a cavity pipe, and a buffering smoke exhaust pipe (11) is communicated with the cavity pipe;

the buffering smoke exhaust pipe (11) is of a pipe body structure with gradually enlarged outer diameter.

3. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded is characterized in that the height of the buffering smoke exhaust pipe (11) is 1/3-3/4 times of the height of the furnace body (2).

4. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded according to the claim 2, wherein the outer diameter of the buffering smoke exhaust pipe (11) ranges from 1.5m to 2.5 m.

5. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded is characterized in that the depth of the buffer smoke exhaust cavity (1) embedded into the furnace body (2) is 1-2 m.

6. The device for preventing flue gas pipeline adhesion of the ferronickel ore hot furnace according to any one of claims 1 to 4, wherein the buffering smoke discharging cavity (1) and the furnace body (2) form an annular gap, and the volume of the annular gap is 80-90 m³。

7. The device for preventing flue gas pipe sticking of a ferronickel ore hot furnace according to any one of claims 1 to 4, wherein the oxygen supply pipeline comprises an oxygen supply main pipe (3) and a plurality of oxygen supply branch pipes (31);

the oxygen supply branch pipes (31) are communicated along the circumferential direction and are arranged around the outside of the furnace body (2).

8. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded according to any one of claims 1 to 4, characterized in that the furnace body (2) is provided with a flue gas inlet section (21), a buffer combustion section (22) and a sedimentation ash discharge section (23) in sequence along the axial direction;

the buffer smoke exhaust cavity (1) is embedded along the smoke inlet section (21) and the buffer combustion section (22);

the oxygen supply pipeline is arranged around the buffer combustion section (22).

9. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded according to the claim 8, wherein the smoke inlet section (21) is of a conical cavity structure, and a smoke inlet pipe (4) is communicated with the smoke inlet section (21);

and a smoke exhaust pipe (5) is communicated with the top of the buffer smoke exhaust cavity (1), and a CO detector (51) is arranged on the smoke exhaust pipe (5).

10. The device for preventing the flue gas pipeline of the ferronickel ore hot furnace from being bonded according to the claim 8, wherein the sedimentation ash discharge section (23) is of a conical cavity structure, and an ash discharge valve (c) is arranged at the bottom of the sedimentation ash discharge section (23);

an access hole (231) is arranged on the side wall of the sedimentation ash discharge section (23).

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