JPS5832307B2 - Top-shaped lime kiln - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention is based on the patent application filed in 1983-1983, which is an earlier invention of the present applicant.
No. 751 (filed on April 11, 1978).

) concerning a top-shaped lime furnace that was further improved.

The present applicant filed a patent application for the first time in Japanese Patent Application No. 5219262 (Japanese Unexamined Patent Publication No. 53-104596) for his original invention, a lime furnace with a top-shaped exterior.
After that, Japanese Patent Application No. 52-69635 (Japanese Patent Application No. 54-429
No. 9) and Japanese Patent Application No. 126485 (1983)
6 (No. 1296) and one after another, improvements were made one after another, but the lime furnace of the above-mentioned patent application No. 54-43751 was completed as a small auxiliary one with a quicklime capacity of 30 tons to 50 tons. It has come into widespread industrial implementation.

In other words, by simply installing this furnace in a large-scale quicklime manufacturing factory that is already in operation, it is possible to make use of the waste fine particles under the sieve of coarsely crushed ore, which cannot be used in the various existing lime furnaces. Currently, we have a proven track record of quicklimeization with excellent thermal efficiency.

The gist of this prior invention is as stated in the preamble of the claims of the present patent application.

The latest improvements include further increasing the thermal efficiency of lime firing to comply with national energy conservation policies, and moving away from the use of a small furnace as an auxiliary firing furnace, resulting in a quicklime account of 100 tf.
, 1 to 3 ootf7, and the gist of the improvement is as described in the characterizing part of the appendix of the claims.

Regarding the drawings, the detailed structure and operation and effects of the new top-type lime kiln including the present improvement will be explained below with reference to FIGS. 3 and 4, partially overlapping the explanation in the prior invention.

By the way, Figure 1 (explanatory cross-sectional elevation) and Figure 2 (
The plan view) is of the prior invention, but FIG. 2 is also common to the present invention.

Reference numerals 1 to 66 are common to both the previous and subsequent inventions, and parts γ0 to r9 belong to the present improvement.

In FIG. 3 and FIG. 2, a circular rail 2 is laid on the middle stage 1a of the pedestal 1 fixedly installed on the ground. 4 is placed thereon and driven by a motor 5. Under the action of a gear 60 fixed to the lower surface of the hearth, the hearth gradually and substantially continuously rotates about its longitudinal core.

The rotation speed is preferably 1 to 2 revolutions per hour.

There is a lower ore drop 2 in the center of the hearth 4, and this ore drop is the first
It is not a normal circle as shown in FIG. 31, but an ellipse, a triangular shape, or an eccentric circle as shown in A, B, and C of FIG. 4 (enlarged view).

(X indicates the axis of rotation, respectively.) A short cylindrical wall γ1 having a diameter larger than that of the ore drop opening 12 is attached to the lower bottom surface of the hearth, and a cylindrical tank γa for aging the fired product having the same diameter is attached to the bottom surface of the hearth through a gap rO.
is connected to.

This gap rO is kept airtight by a gas leak prevention device t6.

A cylindrical tank for ripening the fired product γa connected to the short cylindrical wall r1 on the lower bottom surface of the hearth via a gap rO, and a cooling conical tank yb for cooling the fired product by secondary air, which is integrally connected to the lower bottom of the tank γa. is on a circular rail r4 laid on the lower pedestal r3 by an annular horizontal support plate r9 that supports this integrated body so that the entire body gradually rotates in a horizontal direction opposite to the hearth 4 around the core. The vehicle is placed on the vehicle via wheels r5.

γr is a motor for rotating the above-mentioned integral body, and r8 is the same gear.

Preferably, this rotational speed is approximately twice the hearth 40 rotational speed.

The aging cylindrical tank γa and the cooling conical tank rb include a cylindrical gas passage 38 fixed inside by a support 39, as in the prior invention shown in FIG. Air injection nozzle pipe 40 for circulating hot gas into the tank
At the bottom of the cooling conical tank γb, there are a receiving plate 32 for supporting the continuously falling calcined lime and a scraper 33 for scraping off the calcined quicklime into the quicklime lamp chamber 34.

The quicklime lamp chamber 34 is isolated from the rotation of the cooling conical tank rb by a mechanical rotary seal 35, and the burned quicklime is continuously taken out from the lime furnace by a rotary feeder 36 installed at the bottom of the lamp chamber 34, and conveyed by a belt conveyor 9. It will be carried out.

At the top of the quicklime lamp chamber 34 there is a secondary air intake 31 for fuel combustion.

That is, air is sucked from the secondary air intake 31 by the negative pressure in the furnace chamber caused by the exhaust fan 23, which will be described later, and is cooled by passing through the layer of fired material, and the warmed air rises. The incomplete combustion flame 16 enters the furnace chamber and is injected into the furnace chamber by a burner 14, which will be described later.
It becomes the secondary air for complete combustion.

The warm temperature of the product quicklime to be carried out is 50 to 70°C.

The baffle crown 41 for gas dispersion on the cylindrical gas passage 38 seen in FIG. 1 is not provided in the improved furnace of the present invention for reasons described later.

The structure of the lid and its function are exactly the same as in the prior invention shown in FIGS. 1 and 2.

To repeat this, an upper lid 10 that covers the upper part of the rimmed dish-shaped hearth is suspended from the pedestal 1 by several suspension hooks 11 with turnbuckles, coaxially and horizontally with the hearth. ing.

The distance between the hearth 4 and the upper lid 10 can be freely adjusted by adjusting this turnbuckle.

An annular chamber 12 having a considerable height is located around the upper lid 100.
is provided between the annular chamber 12 and the peripheral wall of the hearth 4 by a gas leak prevention device (for example, a water seal, a sand seal, or an elastic seal) installed on the supporting stage 1b of the pedestal. While preventing the furnace gas from leaking to the outside, the hearth 4 can be rotated without being hindered by the upper cover fixed to the pedestal.

A fuel combustion chamber 15 having a downwardly directed burner 14 attached thereto is connected to the furnace chamber in an open manner at the upper side of the central portion of the upper lid 10 .

1t is the primary air and fuel conduit.

At several locations in the lower part of the annular chamber 12, push rods 52 for pushing the rough stones 20 continuously dropped from the raw material tank 18 from the upper surface of the hearth 4 into the cylindrical tank RA for firing and aging are mounted on the support 1d. The extruder 51 is fixed to the pedestal 1, and is reciprocated in a piston-like manner via a bearing body 50.

Annular chamber 1
An annular partition plate 61 hanging from the ceiling is suspended and fixed inside the chamber 2 to divide the chamber into an annular outer chamber 62 and an inner chamber 63.

Gas flow holes 64 are provided at several locations above the partition plate 61 to allow gas in the inner chamber 63 to flow to the outer chamber 62, and an insertion valve end portion is provided to arbitrarily adjust the opening/closing degree of the flow holes. A regulating valve 65 with a handle for letting in and out is inserted and installed through the side wall of the annular outer chamber.

The waste gas generated in the furnace chamber penetrates the raw material layer on the hearth and exchanges heat with it, is led out of the furnace from several places in the annular outer chamber 62, and collects in the gas reservoir chamber 21 ( The gas temperature is approximately 2000℃.

) This can be exchanged with other substances to utilize its thermal energy, or as shown in the figure, a cyclone type dust remover 22 can be used.
, through the exhaust fan 23 and the chimney 24, and are dissipated into the atmosphere.

Most of the encyclopedic limestone grains 20 in the raw stone storage tank 18 supported by the upper stage 1c of the mount pass through a plurality of main chutes 19 into an annular inner chamber 63, and the remainder pass through a plurality of auxiliary chutes 66. It is continuously thrown into the annular outer chamber 62.

The raw stones put into the inner chamber accumulate on the hearth and flow down toward the reactor core due to the slow rotation of the hearth 4, and a part of them rises from the lower end of the annular partition plate 61 into the annular outer chamber 62. .

However, if this rise is not sufficient, an auxiliary chute 66 assists in charging the raw material into the annular outer chamber 62.

The structural differences between the inventive furnace shown in FIG. 3 and the prior invention inventive furnace shown in FIG. In contrast, in Fig. 3, the ore drop opening r2 has an elliptical or triangular shape coaxial with the furnace axis, or an eccentric circle.

(If) In FIG. 1, the combination of the aging cylindrical tank γa and the cooling conical tank rb is integrated with the rotary hearth 4;
In FIG. 3, the combined body is separated from the cylindrical part r1 at a position rO below the rotary hearth 4, and slowly rotates in the opposite direction to the rotary hearth 4 via a gas leak prevention device r6. What I did.

and (III) point 03 is that the baffle crown 41 provided above the cylindrical gas passage 38 in FIG. 1 is not installed in FIG. 3.

In the furnace of the prior invention shown in FIG. 1, the smoked ore grains falling from the ore drop opening 31 are deposited forming ridge lines on the surface around the cylindrical gas passage 38 as shown in the figure.

Therefore, the circulation of hot gas (at a temperature of 900 to 1300°C) between the cylindrical gas passage and the deposited layer due to the action of the air inlet nozzle pipe is difficult because the layer on the ridge is thicker than the layers on both walls. The disadvantage is that the resistance is large and the entire deposited layer is difficult to ripen uniformly.

In addition, if the inner diameter of the aging cylindrical tank is unnecessarily increased, the thickness of this ridgeline layer will become even thicker, increasing the tendency for non-uniform aging. is the limit.

In this blasting furnace, due to the synergistic effect of the separation and reverse rotation of the hearth and aging cylindrical tank and the irregularly shaped ore drop opening, the upper layer inside the aging cylindrical tank is substantially flattened as shown in Fig. 3. It becomes a horizontal plane.

Therefore, the quicklime is aged homogeneously, and the maturation rate increases and a homogeneous product is obtained.

In addition, even if the diameter of the aging cylindrical tank is increased, the upper surface of the quicklime layer in the tank does not lack a horizontal surface, so the furnace body can be made as large as desired, and the quicklime account ranges from 1ooot to 30mm.
0t independent reactor design is possible.

While the thermal efficiency of the furnace of the prior application was about 80 liters, the thermal efficiency of the furnace of the present invention reaches 85 yen, which greatly contributes to energy saving.

By the way, the thermal efficiency of a conventional rotary kiln type lime furnace is about 60 kiln, and the thermal efficiency of a shaft kiln type lime kiln is about 70 kiln.

In addition, while the outer diameter of the hearth of the first application furnace with a 50 ton account is approximately 8 meters, that of the inventive furnace with a 300 ton account is approximately 1.
It is 1 rice.

The grain size of the raw stone used is 5 to 40 mm, which is the same as in the case of the prior furnace.

The reason why the baffle crown for gas distribution above the ripening cylindrical tank 38 in the prior application furnace was abolished in the present furnace is because it would have rather hindered the fall of Warabi-burned lime grains from the irregularly shaped ore drop opening r2, and This is because it has been found that there is no problem with gas distribution even without it.

It is also a good idea to make the structure as simple as possible when manufacturing the furnace.

[Brief explanation of the drawing]

FIG. 1 is an explanatory longitudinal elevational view of a top-shaped lime kiln according to the invention of the prior application. FIG. 2 is an explanatory plan view of FIG. 1 and FIG. 3 below. FIG. 3 is a longitudinal elevational view of the top-shaped lime kiln of the present invention. FIGS. 4A, B, and C are enlarged plan views of the mine entrance in FIG. 3, respectively. 1... Frame, 2... Circular rail, 3.
...Wheels, 4...Rotating hearth, Ia...
...Aging cylindrical tank, rb...Cooling conical tank, 10
...Top lid, 13...Gas leak prevention device, 14...Burner 15...Fuel combustion chamber, 18...Rough stone storage tank, 19 ...Main throw field chute, 21...Gas reservoir chamber, 34...
...Quicklime lamp room, 3γ...Secondary air intake,
38... Cylindrical gas passage, 40... Air injection nozzle pipe, 41... Obstruction crown, 51...
...Extruder, 52...Pushing rod, 61...
・Annular partition plate, 62... Annular outer chamber, 63...
...Annular inner chamber, 64...Gas circulation hole, 65.
...Adjustment valve, 66...Auxiliary source chute, rO...Gap, rl...Short cylindrical wall,
rl...Ore drop opening, r4...Circular rail, r5...Wheels, rl...Gas leak prevention device, r9...Yen Annular horizontal support plate.

Claims (1)

[Scope of Claims] 1. The main body of the furnace is (I) an opening at the lower center of a dish-shaped hearth 4 with an edge height for ripening the fired material that has fallen from the falling ore opening 31 of the hearth. A cylindrical aging tank γa with an inner diameter larger than the diameter of the cylindrical aging tank γa, followed by a conical cooling tank r for continuously taking out fired products for cooling the fired products with secondary air.
a rotary hearth section placed via wheels 3 on a circular rail 2 laid on a pedestal 1a so that the entire hearth part gradually rotates horizontally around the core; II) A downward-facing tray-shaped upper lid 10 with a ring-shaped periphery covers the upper surface of the rotary hearth 4, and a downward-facing burner 14 is installed at the upper center of the upper lid 10.
The upper lid 10 in the part (n) has an inner circumferential portion with an appropriate height between the upper lid 10 and the dish-shaped hearth 4. The rotary hearth 4 is suspended and fixed to the pedestal 1 so as to form a gap chamber.
The lower end of the periphery of the upper lid 100, which is in contact with the upper end of the periphery of 0, is kept airtight via a gas leak prevention device 13, and the lower end of the outer peripheral wall of the upper lid 10 is equipped with
A circular partition plate 61 that does not reach the position of the push rods is suspended from the ceiling of the upper lid 100, and has a plurality of holes through which the mechanical reciprocating push rods 52 are inserted. The annular portion is fixed to form an annular outer chamber 62 and an annular inner chamber 63.
The main raw material chute 19 is inserted into the annular inner chamber, the auxiliary raw material chute 66 is inserted extending from the raw material tank 18 into the annular outer chamber, and the annular inner chamber is installed at several places above the annular partition plate 61. 6
3 into the annular outer chamber 62 via a regulating valve 65, and from the annular outer chamber 62 to the gas reservoir chamber 21. The waste gas is dissipated into the atmosphere through the cyclone dust remover 22, exhaust fan 23 and chimney 24, while (I
) In the cylindrical aging tank γa, a cylindrical gas passage 38 for circulating hot gas in the quicklime aging layer is fixed to the tank by a support 39, and a secondary gas passage 38 is fixed to the tank by a support 39. In a top-shaped lime kiln comprising an air intake port 3γ, a secondary air injection nozzle pipe 40, and means for continuously taking out burned quicklime, the cylindrical aging tank Ta is cut horizontally at the position of the gap rO. The upper cylinder r1 is separated from the lower cylindrical aging tank γa and the conical cooling tank γb integrally connected thereto, and this upper and lower separation gap rO is kept airtight via a gas leak prevention device r5, and the rotary hearth 4 The shape of the ore drop opening t2 is oval, triangular, or eccentric circular, and the annular horizontal support plate t9 that supports the separated and connected aging tank ra and cooling tank rb is a circular rail laid on the lower stage r3. Wheel γ5 on r4
An improved top-type lime kiln characterized in that it has similar means for gradually rotating it coaxially and oppositely to the rotary hearth 4. 2. The number of revolutions of the hearth part is 1 to 2 revolutions per hour, and the number of revolutions of the aging tank and the cooling tank connected thereto in the opposite direction is approximately twice the number of revolutions of the hearth part, according to claim 1. A top-shaped lime kiln.