CN1098438A

CN1098438A - External heating sponge iron direct reduction furnace

Info

Publication number: CN1098438A
Application number: CN 93115717
Authority: CN
Inventors: 李庆国; 李永祥
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-07-31
Filing date: 1993-07-31
Publication date: 1995-02-08

Abstract

The invention discloses a kind of external heating sponge iron direct reduction furnace.It is to utilize the high Heat Storing Wall of heat transfer efficiency 12 will reduce chamber 4 folders every constructing on furnace foundation 16 with 4 settings of reduction chamber between the combustion chamber 5 and combustion chamber 5.4 internal spaces, reduction chamber of this reduction furnace are higher, can make furnace charge also fully preheating of quilt of adding continuously, heating reach and carry out reduction reaction equably.Because it is simple in structure, less investment, thermo-efficiency height, reliable, thereby is particularly suitable for medium-sized and small enterprises and is used for production high-quality sponge iron.

Description

External heating sponge iron direct reduction furnace

The present invention relates to a kind of iron-smelting device, particularly relate to a kind of utilization direct-reduction process is become sponge iron (direct-reduced iron abbreviates DRI as) by iron ore direct reducing direct reduction unit.

At present, the device with the industrial-scale production sponge iron mainly contains fixed-bed type reduction furnace, fluidized bed type reduction furnace, rotary kiln type reduction furnace and shaft furnace formula direct reduction unit.The fixed-bed type reduction furnace is simple in structure, easy to operate but energy consumption is big, the production cycle is long, yield poorly; Fluidized bed type reduction furnace throughput is big and can be suitable for multiple reductive agent, but complex process, the production cost height; Production lot is big though rotary kiln type reduction furnace and tight stove formula direct reduction unit all have, the advantage of constant product quality but because their cost height, investment is big and not easy to operate and management so that be subjected to many-sided restriction in applying.

The object of the present invention is to provide the sponge iron direct reduction device that a kind of less investment, energy consumption are low, easy to operate and reliable, be convenient to keep in repair.

For achieving the above object, it mainly is the external heating sponge iron direct reduction furnace that is made of furnace shell, combustion chamber, flue, the reduction chamber of erectting installation on the furnace bottom basis that the present invention has adopted a kind of, and the reduction chamber of this reduction furnace is clipped between the combustion chamber and is separated with Heat Storing Wall.

External heating sponge iron direct reduction furnace of the present invention, its Heat Storing Wall are to form with the whole ramming of the high alumina castable that resistance to air loss is good, heat transfer efficiency is high, whole fastness is strong.

Aforesaid external heating sponge iron direct reduction furnace, its reduction chamber inner space height is 17-23 with wide ratio: 1.

External heating sponge iron direct reduction furnace of the present invention can have only reduction two groups of combustion chambers, chamber, also can be built into the structure formation that (Duoing one group than reduction chamber number) combustion chamber is organized in a plurality of reduction chamber more in order to enlarge its throughput.

The present invention has following advantage:

1, because it is simple in structure.Thereby be convenient to construction, management and maintenance and reliable.

But 2 continuous chargings, timing are tapped a blast furnace, the production efficiency height.

3, cost is low, less investment.

4, owing to the structure formation that has adopted furnace body, hot gas flow countercurrent flow in furnace charge and the stove, the thermo-efficiency height, reduction is even, thereby energy consumption is low, constant product quality.

Concrete structure of the present invention is provided by following examples and accompanying drawing thereof.

Fig. 1 is the body of heater Facad structure synoptic diagram of one embodiment of the invention.

Fig. 2 is Fig. 1 " A-A " sectional view.

Fig. 3 is Fig. 2 " B-B " sectional view.

Describe the structure formation and the working condition thereof of the concrete type of furnace that proposes according to the present invention in detail below in conjunction with accompanying drawing.

As Fig. 1 and shown in Figure 3, present embodiment is one and has five groups of combustion chambers 5, the external heating sponge iron direct reduction furnace of four reduction chambers 4, every group of combustion chamber 5 has the burner hearth 8 of a fire-path type as shown in Figure 3, there is a flue 17 5 back, every group of combustion chamber, and combustion chamber 5 and reduction chamber 4 and flue 17, furnace wall 11, insulation of wall floor 10 are all constructed in furnace shell 20 and be located in jointly on the furnace bottom basis 16.

Furnace bottom basis 16 is to irritate prefabricated the forming of stake cast with sand, stone, cement concrete, on furnace bottom basis 16, earlier build into the furnace bottom part by laying bricks or stones with high alumina brick, the furnace bottom part promptly comprises ashpit 19, the burner hearth 8 of 5 bottoms, combustion chamber, the bottom that also comprises reduction 4 bottoms, chamber and flue 17, ashpit 19 and burner hearth 8 " between cast iron stove pillow 14 and cast iron stove strip 13 are installed, be provided with cast iron fire door 15 at the collar extension of body of heater front burner hearth 8; Bottom in reduction chamber 4 is equipped with the iron notch 9 that is welded with steel plate.

After furnace bottom partly is built into can by Fig. 1, shown in Figure 2 with the whole ramming of high alumina castable go out in combustion chamber 5 and the reduction chamber 4, top and flue 17 fronts and left and right sides face wall body, 5 tops, combustion chamber communicate with its flue 17.

Behind above-mentioned casting complete, can carry out building by laying bricks or stones of furnace roof part and furnace wall 11 with refractory fireclay block with reference to Fig. 1 and Fig. 3.Should note when the masonry heater top portion: 5 tops as shown in Figure 3 in the combustion chamber, stay the detection hole 6 that to place the furnace temperature proofing unit, when building reduction front of chamber 4 and back side furnace wall by laying bricks or stones, should reserve can be from stove outside the unlikely again vision slit 3 that the reduction chamber 4 and the external world are communicated of direct viewing reduction situation.

Furnace wall 11 finish building the back also in its appearance with the attached block one deck of diatomite brick thermal insulation layer 10 so that put forward the heat-insulating property of furnace wall 11.

In the present embodiment: furnace shell 20 is to be that 10 millimeters normal carbon steel plate is close to the body of heater welding and is made with thickness; For preventing that the furnace expansion distortion also is provided with reinforcing column 1 and securing gear 7 thereof as shown in Figure 1 and Figure 2 in furnace shell 20 outsides.Reinforcing column 1 is 25 ^#Channel-section steel respectively has four in the body of heater and arranged on left and right sides, in the body of heater front and the back side respectively have ten.Securing gear 7 is that to adopt diameter be that 30 millimeters steel lacing wire and corresponding fastening screw installs.This reduction furnace beam overall C that present embodiment provides is 4000 millimeters, and length overall d is 7000 millimeters, and yearly capacity can reach 3000 tons of high-quality sponge iron, and the construction and installation gross investment only is ten thousand yuans of 50-60.

When this external heating sponge iron direct reduction furnace is used to produce sponge iron, can from fire door 15 in burner hearth 8, drop into the burning and light, can be after temperature is raised to about 1000 ℃ in Heat Storing Wall 12 makes reduction chamber 4 with furnace charge 4 slowly addings continuously suitable for reading from the reduction chamber, the furnace charge of going into stove reduction 4 tops, chamber be subjected to from this indoor ascension and on the hot gas flow preheating, the charge-temperature that falls of healing is higher, " lump ore " in making furnace charge (block virgin iron ore, or the reductive agent that " fine ore pelletizing " is equal in the furnace charge fully carries out reduction reaction and generates sponge iron.The sponge iron that generates continues to fall, and is just regularly emitted from iron notch 9 when arriving reduction 4 bottoms, chamber.5 tops, waste gas auto-combustion chamber that combustion chamber 5 internal combustion produce are descending through flue 17, discharge from the floss hole of bottom of furnace body.

Since among the present invention combustion chamber 5 with reduce between the chamber 4 with accumulation of heat 12 airtight isolation, furnace charge does not directly contact with flame, the impurity that fuel combustion produces can not corrode direct reductive product in the stove, and this just provides reliable assurance for the sponge iron chemical composition stability of producing.

In the present embodiment, " high and wide ratio " of reduction 4 internal spaces, chamber be big (a=6900 millimeter, b=320 millimeter), drops into furnace charge in the stove continuously in dropping process slowly, can guarantee that it is by preheating fully, heating with fully carry out reduction reaction; In addition, in reduction 4 bottoms, chamber because temperature is lower herein, the sponge iron of generation cool off herein liberated heat also ascension immediately arrive reduction 4 tops, chamber again and participate in above-mentioned working process; In addition, waste gas can make when descending its waste heat energy width of cloth penetrate conduction in flue 17 to give the headspace of combustion chamber 5 and reduction chamber 4 and obtain reclaiming and utilizing in the stove.Detection hole 6 by furnace roof can utilize thermo detector to monitor the furnace temperature variation at any time, also can in time observe the reaction condition of furnace charge in stove from the vision slit 3 of reduction chamber 4, so that adjust " duration and degree of heating " in good time, thereby, can fuel saving consumption, can guarantee this stove safe operation again.

The present inventor was that 5440 millimeters, a are 7360 millimeters with a respectively once also, and b is 320 millimeters external heating sponge iron direct reduction furnaces for reduction chamber 4 internal space height and width and carried out production test as embodiment, and its effect is also all very desirable.

Claims

1, a kind of external heating sponge iron direct reduction furnace, it is constituted by go up furnace wall (11), furnace shell (20), combustion chamber (5), flue (17), the reduction chamber (4) of erectting installation in furnace bottom basis (16), and it is characterized in that: reduction chamber (4) is sandwiched between the combustion chamber (5) and is separated with Heat Storing Wall (12).

2, external heating sponge iron direct reduction furnace as claimed in claim 1 is characterized in that: Heat Storing Wall (12) is to form with the whole ramming of high alumina castable.

3, external heating sponge iron direct reduction furnace as claimed in claim 1 is characterized in that: the height of reduction internal space, chamber (4) is 17-23 with wide ratio: 1.