WO2020052269A1 - Cement clinker preparation method and apparatus - Google Patents

Abstract

A cement clinker preparation method, comprising applying a voltage to a blank to fire the blank to obtain cement clinker under the condition of 900-1200°C, wherein the blank is obtained by pre-firing cement raw meal at 900-1200°C. A cement clinker preparation apparatus, comprising a rotary kiln, wherein the rotary kiln is provided with a feed port and a discharge port; a first electrode collar and a second electrode collar are sequentially provided in the rotary kiln in a direction from the feed port to the discharge port; the first electrode collar and the second electrode collar are provided with notches; the area between the first electrode collar and the second electrode collar is an electric heating area.

Description

Method and device for preparing cement clinker Technical field

The invention belongs to the technical field of cement preparation, and particularly relates to a method for preparing cement clinker.

Background technique

Existing methods for preparing cement clinker include cyclone firing method and boiling firing method. In addition, the United States has conducted research on the production of clinker in a plasma flame kiln. In addition, the use of electromagnetic radiation in the infrared range allows the material to pass through the calcination of the high-temperature electric heating layer; the energy conversion efficiency of the laser heating method can reach 50%, which makes it an extremely effective fast heater heat source. Although various existing methods have the characteristics of rapid (low-temperature or high-temperature) calcination, the efficiency is not high and the environmental protection effect is not ideal.

Summary of the Invention

In view of the defects and deficiencies in the prior art, the present invention provides a method for preparing cement clinker.

The method for preparing cement clinker provided by the present invention includes: applying a voltage on the material embryo to fire the material clinker under the condition of 900-1200 ° C; the material embryo is a cement raw powder under the condition of 900-1200 ° C Calcined.

Further, in the method of the present invention, at a temperature of 900-1200 ° C, a voltage is applied to the raw material to fire the raw material for 15-600 seconds to obtain cement clinker. The raw material is pre-fired cement raw powder at 900-1200 ° C. Obtained in 10-60 minutes; the magnitude of the applied voltage in the axial direction of the blank is 10-200V / mm, and the sintering current in the radial section of the blank is 5-50 mA / mm ² .

At the same time, the invention also provides a device for preparing cement clinker.

The device provided by the present invention includes a rotary kiln. The rotary kiln is provided with a feeding port and a discharging port. The rotary kiln is provided with a first electrode ring and a second electrode in the order of the feeding port to the discharging port. In the electrode ring, a notch is provided on the first electrode ring, a notch is provided on the second electrode ring, and a region between the first electrode ring and the second electrolytic ring is an electric burning zone.

Preferably, the first electrode ring of the present invention is provided with a plurality of notches, and the second electrode ring is provided with a plurality of notches.

In some embodiments, the device of the present invention includes a conductive ring disposed on an outer wall of the rotary kiln, and the conductive ring is electrically connected to the first electrode ring and the second electrode ring.

In some embodiments, the device of the present invention includes a brush disposed outside the rotary kiln, and the brush is electrically connected to the conductive ring.

Further, the outer wall of the rotary kiln of the present invention is provided with a refractory kiln lining.

In some embodiments, the cement raw powder calcined section is between the feed port of the present invention and the first electrode ring.

The advantages of the invention are:

(1) The present invention adopts electric current sintering cement clinker, and the time for clinker formation is greatly shortened. From the traditional furnace temperature of 1400-1500 ° C, sintering for 1 hour, the furnace temperature is reduced to 900-1200 ° C, the sintering time is at least 15 seconds, The rate of formation is more than 100 times, the maximum furnace temperature is reduced by more than 200 degrees, and the quality of the obtained cement clinker is good.

(2) The technology of the present invention has low energy consumption, low power consumption, and environmental friendliness. It can use renewable surplus electrical energy, has good economic benefits, and good ecological and environmental benefits, and is a revolutionary revolutionary technology for green production in the cement industry.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a reference schematic diagram of the device of the present invention;

Fig. 2 is a sectional view taken along the line A-A in Fig. 1.

detailed description

The cement raw powder is a cement raw powder in a traditional cement clinker preparation process. For example, the weight percentage content and ratio of cement raw meal powder in a cement plant are as follows:

Table 1

SiO2	Al2O3	Fe2O3	CaO	MgO	K2O	Na2O	SO3	KH	SM	IM
13.05	3.01	2.25	42.52	2.15	0.57	0.1	0.28	1.01	2.48	1.34

Example 1:

The raw meal powder was calcined at 1100 ° C for 0.5 hours to obtain a blank. An electrode was added to the blank, and then the electric field strength was 100V / mm at 1160 ° C, the current was controlled at 10 mA / mm ² , and it was quickly cooled after being energized for 30 seconds. The cement clinker was obtained at room temperature. The results of XRD semi-quantitative measurement of clinker mineral crystal content are shown in Table 2:

Table 2

C3S%	C2S%	C3A%	C4AF%
31	48	12	9

Example 2:

The raw meal powder is calcined at 1200 ° C for 1 hour to obtain a blank. An electrode is added to the blank, and then the electric field strength is 200V / mm at 1168 ° C, the current is controlled at 20 mA / mm ² , and it is cooled to room temperature after being applied for 300 seconds. The cement clinker was obtained, and the XRD semi-quantitative test results of the mineral crystal content of the clinker are shown in Table 3:

table 3

C3S%	C2S%	C3A%	C4AF%
65	19	10	6

Example 3:

The raw raw meal powder is calcined at 1000 ° C for 40 minutes to obtain a blank. Then, an electrode is added to the blank, and then at 1000 ° C, the electric field strength is 20V / mm, the current is controlled at 5 mA / mm ² , and it is cooled to 600 seconds after being energized. Cement clinker was obtained at room temperature, and the results of XRD semi-quantitative measurement of clinker mineral crystal content are shown in Table 4:

Table 4

C3S%	C2S%	C3A%	C4AF%
70	14	9	7

Example 4:

The raw raw meal powder was calcined at 900 ° C for 1 hour to obtain a blank. An electrode was added to the blank, and the electric field strength was 200V / mm, and the current was controlled at 40mA / mm ² at a furnace temperature of 1000 ° C. After being applied for 100 seconds, Quickly cool to room temperature to obtain cement clinker. XRD semi-quantitative test results of mineral crystal content of clinker are shown in Table 5:

table 5

C3S%	C2S%	C3A%	C4AF%
59	twenty one	11	9

Example 5:

The raw meal powder was calcined at 1100 ° C for 1 hour to obtain a blank. An electrode was added to the blank, and then at a furnace temperature of 1140 ° C, the electric field strength was 90 V / mm, and the current was controlled at 30 mA / mm ^2. After being energized for 120 seconds, After cooling to room temperature, cement clinker is obtained. The XRD semi-quantitative test results of the mineral crystal content of the clinker are shown in Table 6:

Table 6

C3S%	C2S%	C3A%	C4AF%
66	19	9	6

Example 6:

The raw raw meal powder was calcined at 1200 ° C for 1.5 hours to obtain a blank. Then, an electrode was added to the blank, and the electric field strength was 20V / mm at a furnace temperature of 1190 ° C, and the current was controlled at 15 mA / mm ^2. After being applied for 600 seconds, After cooling to room temperature, cement clinker was obtained. The results of semi-quantitative XRD test on the crystal content of clinker minerals are shown in Table 7:

Table 7

C3S%

C2S%

C3A%

C4AF%

60

twenty two

10

8

Example 7:

As shown in FIGS. 1 and 2, the cement clinker preparation device of this embodiment includes a rotary kiln 11. During operation, power is supplied to two electrode rings 2 fixed in the kiln body. The gap 9 on the electrode ring of the material inlet enters the electric burning zone 10 between the two electrode rings. The cement material between the two electrode rings 2 is sintered by the electric current under the action of the electric field. The material is discharged through the notch 9 of the other electrode ring.

In some embodiments, the power supply of the two electrode rings 2 is: a brush 1 is provided outside the rotary kiln 11, the fixed brush 1 is in contact with a rotating conductive ring 4 provided on the outer wall of the rotary kiln, and the conductive ring 4 It is electrically connected to the two electrode coils.

In some preferred embodiments, there may be multiple gaps on the two motor rings. As shown in FIG. 2, four gaps 9 are evenly arranged along the circumferential direction.

In other embodiments, the refractory kiln liner 3 may be provided on the rotary kiln.

In some embodiments, the area between the feed port of the rotary kiln and the first electrode ring 2 (the electrode ring close to the feed port) is a cement raw material calcining section. The process shown in Examples 1-6 can be performed at The one-time feeding and discharging are completed in the device.

The rotary kiln is also provided with conventional driving support components, as shown in Figures 1 and 2, where the reducer 6 drives the large gear 8 to drive the rotary kiln to rotate, and the belt 5 is supported by the supporting roller 7 to support the rotation of the kiln body and the cement material Enter from one end of the rotary kiln and discharge from the other end.

Claims (8)

1. A method for preparing cement clinker, which is characterized in that the method comprises: applying a voltage on the raw material at 900-1200 ° C to fire the raw material to obtain cement clinker; the raw material is a cement raw powder at 900 Obtained at -1200 ℃.
2. The method for preparing cement clinker according to claim 1, characterized in that the cement clinker is obtained after firing a voltage of 15-600 seconds at a temperature of 900-1200 ° C under a voltage applied to the billet; the billet is The cement raw powder is pre-fired at 900-1200 ° C for 10-60 minutes; the applied voltage in the axial direction of the preform is 10-200V / mm, and the sintering current in the radial section of the preform is 5-50mA / mm ² .
3. A cement clinker preparation device is characterized in that the device comprises a rotary kiln, wherein the rotary kiln is provided with a feeding port and a discharging port, and the rotary kiln is provided in order along the direction of the feeding port to the discharging port. A first electrode ring and a second electrode ring, a gap is provided on the first electrode ring, a gap is provided on the second electrode ring, and a region between the first electrode ring and the second electrolytic ring is a burn-in area .
4. The cement clinker preparation device according to claim 3, wherein the first electrode ring is provided with a plurality of notches, and the second electrode ring is provided with a plurality of notches.
5. The cement clinker preparation device according to claim 3, wherein the device comprises a conductive ring, the conductive ring is disposed on the outer wall of the rotary kiln, the conductive ring is connected to the first electrode ring and the second electrode ring Electrical connection.
6. The cement clinker preparation device according to claim 5, wherein the device comprises a brush, the brush is disposed outside the rotary kiln, and the brush is electrically connected to the conductive ring.
7. The cement clinker preparation device according to claim 3, wherein the outer wall of the rotary kiln is provided with a refractory kiln lining.
8. The cement clinker preparation device according to claim 3, wherein the cement raw powder pre-burning section is between the feed port and the first electrode ring.

Images