JPS5913004A - Production device for vitreous blast furnace slag - Google Patents

Abstract

PURPOSE:To enable the extremely stable discharge of the blast furnace slag in the plural grooves in the rotating direction on the circumference of a rotary drum without requiring any pressing plate in a titled device which flows said slag into said grooves and cools the slag by opening the bottom of the grooves and injecting fluid thereto. CONSTITUTION:The molten blast furnace slag 11 from a supply mechanism 9 is run into the groove 15 near the peak part of a drum 4 under rotation, and is quickly cooled by contact with a metallic plate 14' to form vitreous blast furnace slag 11'. The groove 15 has an introducing part expanding toward the outside of the drum and a cooling part narrowing toward the inside of the drum in succession to said part, and the width at the top end of the latter is made 3-8mm. and the width at the bottom end 0.3-0.6mm.. Then, even if the bottom of the groove 15 is held open, the slag 11 does not flow downward. The high pressure fluid from a nozzle 16 supported on the inside of the drum 4 is injected to the slag 11' in the groove 15 brought to the lower position by the rotation of the drum 4 through the opened bottom of the groove 15, by which the slag 11' is made into a small lumped shape and is discharged into the water tank on the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved apparatus for producing vitreous blast furnace slag.

Conventionally, as a device for producing glassy blast furnace slag by rapidly cooling and solidifying molten blast furnace slag in a dry process, a length parallel to the rotation direction is used to rapidly cool and solidify the molten blast furnace slag to make glassy blast furnace slag. a rotating drum having a plurality of directional grooves formed on its outer peripheral surface by a metal member; a driving means for rotating the rotating drum; and a highest position of the rotating drum disposed above the rotating drum. A feeding means for pouring molten blast furnace slag □ into the groove in the vicinity thereof, a die cutting means for crystallizing the vitreous blast furnace slag from the groove; There is a known apparatus for producing vitreous blast furnace slag, which has a cooling means for cooling the metal member, and the grooves are gradually narrowed from the outside to the inside of the rotating drum. (Refer to Japanese Patent Publication No. 55-54026).

Conventional production equipment for such vitreous blast furnace slag produces vitreous blast furnace slag that has low porosity, virtually no water content, excellent pulverizability, and is of excellent quality as a raw material for cement and a raw material for calcium silicate fertilizers. Blast furnace slag is obtained.

However, in the above-described conventional apparatus for manufacturing vitreous blast furnace slag, a press plate, for example, is used as the die cutting means. That is, as shown in the cross-sectional view in FIG.
2 is a metal member, 2 is a groove for rapidly cooling and solidifying molten blast furnace slag into glassy blast furnace slag, and a push plate 3 is provided at the bottom of the groove 2, which can be raised and lowered in the depth direction of the groove 2. It is being As shown in FIG. 1, with the push plate 3 lowered, molten blast furnace slag is poured into the groove 2.1. This is rapidly cooled and crushed by the metal member 1 to become vitreous blast furnace slag. Then, by pushing the push plate 3 into the groove 2,
The vitreous blast furnace slag in the groove 2 is discharged outside the groove 2.

Such a push plate 3 is provided independently for each groove 2, and liquid crystal is alternately applied to high-temperature molten blast furnace slag and cooling water. Therefore, under such severe temperature cycles, each push plate 3 must be repeatedly raised and lowered independently within the narrow groove 2, which makes stable operation difficult and difficult to maintain. 1. Selection etc. are troublesome. There was a problem. Therefore, the present inventors conducted research to solve the above problems, and as a result, they obtained the following general knowledge.

(1) The molten blast furnace sly poured into narrow grooves made of metal material comes into contact with the metal material, is rapidly cooled, and solidifies in an extremely short period of time, so the width of the bottom of the grooves should be narrowly spaced. Even if I open the bottom,...
Molten blast furnace slag poured into the groove does not flow out from the bottom of the groove. (2) By injecting high-pressure fluid into the bottom of the open groove, the resulting vitreous blast furnace slag is deposited in the groove under the pressure (energy) of the injected fluid. )6, it is easily expelled to the outside.

Therefore, there is no need for a conventional press plate.

(3) Since a push plate is not required in a groove with an open bottom, the width of the groove (especially in the middle of the lower end) can be made narrower than that of the conventional one, and as a result, the width of the groove is narrower than that of the conventional one. Productivity improves.

This invention has been made based on the above knowledge, and it is possible to form a plurality of grooves with a length parallel to the rotation direction in a metal member for rapidly cooling and solidifying molten blast furnace slag into glassy blast furnace slag. a rotating drum formed on an outer circumferential surface by a rotating drum; a driving means for rotating the rotating drum;
a supply means disposed above the rotating drum for pouring molten blast furnace slag into the groove near the highest position of the rotating drum; and a cooling means for cooling the metal member of the rotary drum, the groove being gradually narrowed from the outside of the rotary drum to the inside of the rotary drum. In the apparatus for producing vitreous blast furnace slag, the bottom of the groove is open to the inside of the rotating drum, and the groove is connected to the rotating drum for introducing molten blast furnace slag. an introduction section that widens toward the outside of the drum; and a cooling section that narrows toward the inside of the rotating drum following the introduction section for rapidly cooling and solidifying molten blast furnace slag into glassy blast furnace slag. The cooling part consists of 3 to 8I1
1++1 upper middle and 0.3-0.6. a lower end, and the die-cutting means injects a fluid toward the bottom of the groove disposed inside the rotating drum to remove the vitreous blast furnace slag in the groove to the outside. It is characterized by comprising a fluid ejection mechanism for discharging water.

The present invention will be described below with reference to embodiments and drawings.

FIG. 2 is a schematic front view showing one embodiment of the apparatus for producing vitreous blast furnace slag according to the present invention. As shown in FIG. A plurality of grooves having a length direction parallel to the direction of rotation are formed by a metal member to rapidly cool and solidify the molten blast furnace slag into glassy blast furnace slag. At both ends in the axial direction, it is connected to two hollow rotating shafts 5 located at the axial center positions by connecting members 6 (part of which is shown in the figure).

7 is a bearing for the hollow rotating shaft 5, and 8 is a supporting member for the bearing 7. By driving the hollow rotating shaft 5 by a drive device (not shown), the rotating drum 4 rotates at a predetermined speed in the direction of the arrow in the figure. .

A molten blast furnace slag supply mechanism 9 is arranged above and close to the rotating drum 4. The supply mechanism 9 has a slag container 10 which receives molten blast furnace slag 11 from a blast furnace (not shown) through a gutter 12 from an opening at its upper end. Slag container 10
Molten blast furnace slag 11 is poured into the groove from the nozzle 10a at the bottom of the rotary drum 4 near the highest position. The slag container 10 is also provided with a slit mechanism 13 for adjusting the amount of slag flowing out from the nozzle 10a. A shielding plate that slides on the fixed plate is provided, and by moving the shielding plate, the slit opening area of the fixed plate is adjusted, and thus the amount of ° slag flowing out from the nozzle 10a is adjusted. Further, at the upper end of the slag container 10, there is located an introduction end of an overflow gutter 10' for guiding the molten blast furnace slag 11 overflowing therefrom to a dry bit or the like (not shown).

The rotating drum 4 is made up of a plurality of arc-shaped metal members 14, and as shown in a cross-sectional view in FIG. It consists of a plate 14'.

The metal plate 14' is made of a metal with high thermal conductivity such as copper. The plurality of metal plates 14 are mutually tightened and fixed by a tightening rod 19 via a spacer 18 at a portion closer to the inside of the rotating drum 4. Thus, the metal members 14 tighten the outer circumference of the rotating drum 4. A plurality of grooves 15 are formed on the surface, the length of which is parallel to the direction of rotation, and which gradually become narrower from the outside to the inside.The bottom of the groove 15 is open.Groove 15 1 includes an introduction portion for introducing molten blast furnace slag, which is composed of two mutually opposing opening surfaces 15a and 15b with a relatively large inclination angle with respect to the vertical line, and two opening surfaces 15a and 15.
The molten blast furnace slag is rapidly cooled and solidified, which is continuous to the introduction section and is composed of two mutually opposing cooling surfaces 15c and 15d that have a small inclination angle with respect to the vertical line.

It consists of a cooling section for converting into glassy blast furnace slag.

Reference numeral 16 denotes a plurality of nozzles for ejecting fluid (e.g., air, water), which are arranged inside the rotating drum 4 and close to its lower part, and correspond to each of the plurality of grooves 15 of the metal member 14. Thus, each nozzle 16 is provided along the axial direction of the rotating drum 4, and is provided in two rows in the rotational direction of the rotating drum 4. The fluid ejected from the nozzle 16 is therefore blown into the groove 15 via the bottom thereof. Note that the nozzle 16 penetrates through the two hollow rotating shafts 5 at the axial center position of the rotating drum 4 and is partially disposed inside the rotating drum 4 between these hollow rotating shafts 50. A fluid supply pipe (not shown) supported and fixed on the outside is supported on the inside of the rotating drum 4, and fluid is supplied from the outside through this fluid supply pipe.

Reference numeral 17 denotes a water tank, and this water tank 17 is arranged below the rotating drum 4, and the lower part (metal member 14) of the rotating drum 4 is submerged therein for cooling.

With such a configuration, the molten blast furnace slag supply mechanism 9
The molten blast furnace slag 11 from above is poured into the groove 15 near the highest position of the rotating rotating drum 4, where it contacts the metal plate 14', thereby being rapidly cooled and solidified to form the vitreous blast furnace slag 11. '. As the rotary drum 4 rotates, the vitreous blast furnace slag 11' in the groove 15, which has reached the lower position of the rotary drum 4, is exposed to the vitreous blast furnace slag 11' through the open bottom of the groove 15 (in this position, the groove The bottom of 15 is groove 15
High-pressure fluid is injected from the nozzle 16 (which is at the top position of
is discharged outside (into the heather tank 17) in the form of small lumps. The metal part, material 14, is cooled by water, the water in the tank 17,
As the rotary drum 4 rotates, it reaches near its highest position, where the molten blast furnace slag 11 is again received into the groove 14, and the slag is rapidly solidified to form glassy blast furnace slag. In addition, since the fluid injected from the nozzle 16 is blown into the groove 15 when the vitreous blast furnace slag is discharged, the inside of the groove 15 is cleaned. Moreover, since fluid is blown into the groove 15 from two nozzles 16 in series in the rotational direction of the rotary drum 4, the discharge of the glassy blast furnace slag and the cleaning of the groove can be performed more reliably. The water in the water tank 17 absorbs the heat of the molten blast furnace slag and cools the metal member 14, which has become hot, so it boils over and the vitreous blast furnace slag in the water tank 17 also cools down. Since it has a high temperature, if this glassy blast furnace slag is removed from the water tank 17 by an appropriate means, the moisture on its surface will immediately evaporate and it will contain almost no moisture (the molten blast furnace slag 11 is a metal By cooling the opposing cooling surfaces 1.5c and 15d that form the cooling portion of the groove 15 of the member 14, it becomes glassy, so its properties are not porous, and therefore the water content is ).

Next, the productivity of vitreous blast furnace slag in the present invention will be explained. FIG. 4 μ is a schematic cross-sectional view of the metal plate 14' and the groove 15 according to the present invention, modified for the sake of explanation. As shown in Figure 4, the width of the bottom of the groove 15 (in the middle of the lower end) is
(-) and pour the molten blast furnace slag into the groove 15 to a height of h (mm), the upper end of the glassy blast furnace slag 11' obtained in the groove 15 becomes b (■). Let the slope of the groove 15 be α and define it as in equation (1), then (1
Two equations hold true. .

α= (b, -a)/2h...
(1).

h = (, b - a), /2α
...(1 vitreous blast furnace slag 11
' cross-sectional area A (,l1l)4, expressed by equation (2). ,.

A=(b+a)Xh/2=(b'-a')/4α・(2
) The cross-sectional shape of the metal plate 14' is such that the width at the pouring height h of the molten blast furnace slag is b' (m ), and the width is 2 h upward from the lower end (bottom) of the groove 15 and the width is downward from the lower end (bottom) of the groove 15. It has a height of h. Therefore, the cross-sectional area B(, d
) is expressed by equation (3).

阜=3. b'h,...
・(3) A can be approximated as in equation (4), so A and B
The ratio of .

is expressed by equation (5).

, A ”' bh・
...(4), A/B = b h/3. b'h = b
/3b'...(5) Now the specific heat is 0.301. 1. Cooling molten blast furnace slag from 1500°C to 600°C (average) at l/Kt·°C and specific gravity 3.0.
On the other hand, if the metal plate 14' is made of copper, its specific heat is 0.09
The temperature of the metal plate 14' cooled in a 100°C water tank was 120°C (average), immediately before discharging the vitreous blast furnace slag.

When the temperature of the metal plate 14' is 250°C (average), (
Equation 6) is established, and when this is rearranged, Equation (6') is obtained. , ・(1500-600)"OXo, 30W/Kg・'QX
3. OX A m'〒(250-120)℃X0.0
9m, l/Kg・'(3X9.0XB-...(6)?
,8A=BsugiwachiA/B=1/7.8
...(6) By substituting equation (69) into equation (5), equation (7) is obtained.

A/B=b/3b'=1/7.8 or b/b'-
1/2.6...(7) Groove 15 formed by metal plate 14'
If the pitch of is W (am), W can be expressed by equation (8).

w=b+b'=b+ 2.6 b=3.6 b
-(8) Now, if the width of the rotating drum 4 is W (g), the number N of grooves 15 on the rotating drum 4 can be expressed by equation (9).

No + 1 = 100OW/w = iooow/
3.6 b - (9) Since NG>1, (9)
The equation can be approximated by equation (10).

NQ = 100OW/3.6b = 278W/b
-(10) Now, the cooling time required for the molten blast furnace slag poured into the groove 15 to reach a certain temperature (here, 600°C) and be discharged is T (see)
If so, the parabolic side generally holds true and is expressed by equation (11).

Gaku = kb ... (1
1) k is a coefficient. In the figure 7-shaped groove 15, b is the thickest part, so T is determined by the cooling rate of part b. In the experiments conducted by the inventors, when b = 6 am, T
= 5 sec, so by substituting this value into equation (l), 9k is found in equation (121).

In addition, when it is 556 mm, a vitrification rate of 98% or more is obtained.

He 1 (X6 k-to/6...(
121 In the present invention, assuming that the molten blast furnace slag is poured into the groove 15 near the highest position of the rotating drum and the vitreous blast furnace slag is discharged near the lowest part of the rotating drum 4, the time required for one rotation of the rotating drum 4 is is 2 T (se
e). Therefore, the rotation speed of the drum is r (rpm)
Then, equation (13) holds true.

r = 60/2T= 3o/T-'? (k'l')-
30X36/(5b') -216/b'
...(131Here, if the diameter of the rotating drum 4 is D (c), the productivity of the device P (t/j''
) is expressed by the formula 04).

P- (slag cross-sectional area of one groove) x (drum circumferential speed) x (number of grooves) x (slag specific gravity) = -X A W, for example D=
By setting 2m1W=2m and further determining the width a of the bottom of the groove 15 and the slope α, the relationship between the productivity P and the upper end of the vitreous blast furnace slag in the groove 15 can be determined.

In the conventional device as described above (see Japanese Patent Application Laid-open No. 55-54026) that uses a push plate at the bottom of the groove, the width of the bottom of the groove needs to be about 2 cm even if it is the smallest, considering the usage condition. It is. - Since there is no press plate in the strength tree invention, the width a of the bottom of the groove 15 can be 2+w or less, for example, 0.3 to 0.6 m.

In the rotating drum 4 with D==2m and W=2m, the groove 15
In order to facilitate the discharge of the vitreous blast furnace slag, the slope of the groove 15 is set to α”-100, and the width a of the bottom of the groove 15 is set to 0.
．． 5+mn and 1.0+nm, the relationship between the upper end of the vitreous blast furnace slag in the groove 15 and the productivity P can be calculated as shown in FIG. For comparison, in a conventional device using a rotating drum with D, W, and α the same as above, and with the width a of the bottom of the groove set to 2 mm and a push plate installed there, The calculation results of the relationship between the upper end of the vitreous blast furnace slag and the productivity P are shown in FIG. As can be seen from FIG. 5, in the groove using the push plate, the maximum productivity P is around b=3.5 mm, which is 2.7 t/m. On the other hand, in a groove without a push plate,
For example, when B=Q and 5wn, P=10.8t/III+ becomes the highest value near b=0.9 mm. However, this value can only be obtained by calculation, and whether or not this state can be realized requires consideration of the rotation speed of the rotary drum 4 as well. The relationship between b and the rotational speed of the rotating drum is (1
3) As shown in the formula, the calculation results are as shown in the table below.

As can be seen from the table, when b = Q and 9 ma, the rotational speed of the rotating drum becomes more than 20 Orpm, and it is impossible to inject slag into the groove. Considering the circumferential speed of the rotating drum, a speed of 1'OOrPm or more causes many problems, and for practical purposes, a speed of 50 rpm or less is preferable. In the case of a groove with a diameter of 0.5 m, the rotation speed of the rotating drum is 34.5 rpm when b = 2.5 tan, and the productivity P at this time is 5.4 t/m. The highest value of 2.
7 It is exactly twice that of t/-. Also b=3.0m
m (a=0.5m+), the drum rotation speed is 24 rpm
However, the productivity at this time was 4.6 t/-, which is approximately 1.7 times the maximum value of 2.7 t/m for the push plate method.

Next, the reason for numerically limiting the width of the bottom of the groove in the present invention will be explained.

A plurality of plates having the cross-sectional shape shown in FIG. 4 were manufactured using copper and steel. By combining these plates, a shown in Fig. 4 is 0.3, 0.5, 0.6, 0.7, 0.8 (m
) Groove 15 was formed so as to fit. Then, the temperature of these metal plates was preheated to about 120°C, and when molten blast furnace slag was poured into this groove 15 so that b = 10 (-), the molten blast furnace slag flowed down from the bottom of the groove 15. The results are shown in Table 1.

When the molten blast furnace slag flows down from the bottom of the groove 15 and solidifies,
It is difficult to discharge this from the groove 15 by fluid jetting. Such molten blast furnace slug does not flow down from the groove.

×Nislag flowed down from the ditch.

It is believed that the phenomenon of flowing down of molten blast furnace slag is determined by the solidification and surface tension of molten blast furnace slag, so in the present invention, a is preferably 0.6 or less.

Next, an experiment was conducted in which the glassy blast furnace slag obtained by rapidly cooling and solidifying the molten blast furnace slag in the groove 15 described above was discharged from the groove 15. Air and water were used as fluids in the drain at the pressures shown in Table 2.

The results are shown in Table 2.

In this way, the vitreous blast furnace slag in the groove 15 is removed from the second
Mark O on the table: The discharge was completed.

Moreover, after the slag was discharged, the groove 15 was cleaned with air or water, so that no fine slag fragments remained. In addition, if a is less than 0.3■,
It is not possible to blow enough shore force fluid into the groove 15 to reliably discharge the vitreous blast furnace slag. Therefore, in the present invention, a: '0.3 to 0
．． 6■ is preferable.

On the other hand, as shown in FIG. 3, the upper end of the cooling portion of the groove 15 preferably has a thickness of 3 to 8 cm. If it is less than 3 m, the molten blast furnace slag cannot be sufficiently poured into the groove 15,
On the other hand, if the amount exceeds 8, glassy blast furnace slag with a high vitrification rate cannot be obtained. In addition, if the upper end of the cooling part is set to 6 or less, a positive blast furnace waste lag having an extremely high vitrification rate can be obtained.
・As shown in FIG. 6, near the highest position of the rotary drum 4, contact the bottom of the groove 15 formed by the metal member 14 on the inner side, and place the open bottom at the highest position of the rotary drum 4. An arcuate plate 20 (supported by a suitable support means (not shown), fixed to the fluid supply pipe in the rotating drum 4 described above) is required to temporarily block it while it is in the vicinity. It may be provided depending on the situation.

As explained above, in this invention, the bottom of the groove is opened and the fluid is injected there, so that the glassy blast furnace slag obtained inside can be discharged to the outside in an extremely reliable and stable manner. . Furthermore, since no push plate or the like is required, the equipment can be of a simple structure.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a groove portion in a conventional apparatus for producing vitreous blast furnace slag, FIG. 2 is a schematic configuration diagram showing one embodiment of an apparatus for producing vitreous blast furnace slag according to the present invention, and FIG. FIG. 4 is a cross-sectional view showing a modified example of the groove in the apparatus, FIG. 5 is a diagram showing the relationship between the production efficiency of glassy blast furnace slag and the groove size, and FIG. It is a schematic diagram showing a part of other one aspect of quality blast furnace slag. 15...Groove 16...Nozzle applicant
Representative of Nippon Kokan Co., Ltd. Keizuo Shioya (2 others) -23= Ne! Decoy 2232-, Figure 6・? ! O

Claims (2)

[Claims] (1) A rotating drum in which a plurality of grooves with a length direction parallel to the rotation direction are formed on the outer peripheral surface of a metal member for rapidly cooling and solidifying molten blast furnace slag to form glassy blast furnace slag; a drive means for rotating the rotary drum; a supply means disposed above the rotary drum for pouring molten blast furnace slag into the groove near the highest position of the rotary drum; and a cooling means for cooling the metal member of the rotating drum. Toward 1. In an apparatus for producing vitreous blast furnace slag, the bottom of which is gradually becoming narrower, the groove is open at its bottom to the inside of the rotating drum, and the groove is a chamber for introducing molten blast furnace slag. an inlet section that widens toward the outside of the rotating drum; and a cooling section that narrows toward the inside of the rotary drum following the inlet section for rapidly cooling and solidifying the molten blast furnace slag into glassy blast furnace slag. The cooling part consists of a 3-8 m upper end and a 0.3-0.611 m upper end.
II++ in the lower end, said die-cutting means being disposed inside said rotating drum;
An apparatus for producing vitreous blast furnace slag, comprising a fluid injection mechanism for injecting fluid toward the bottom of the groove to discharge the vitreous blast furnace slag in the groove to the outside. (2) The apparatus for producing vitreous blast furnace slag according to claim 11, wherein the cooling portion has an upper end of 3 to 6.