INTEGRATED DRYING PROCESS AND DEVICE FOR DRY GRANULATED SLAG AND SLUDGE

Abstract

An integrated drying process and device for dry granulated slag and sludge. The process comprises the following steps: 1) slag ball mixing and soaking: high-temperature slag and steel balls are fully mixed and exchange heat therebetween, the high-temperature slag is cooled because the heat thereof is quickly absorbed by the steel balls and is crushed to form granular slag, and the temperature of the steel balls rises because the steel balls absorb the heat of the high-temperature slag; and 2) sludge drying: the high-temperature steel balls are conveyed to a sludge drying device to be mixed with injected sludge, the sludge is dried, the steel balls are separated from the sludge when the water content of the sludge reaches a set value, and the steel balls and the sludge are separately discharged. In the present invention, high-temperature slag waste heat is used for heating steel balls, and sludge is dried by means of the heated steel balls, thus achieving the cooperative treatment of slag cooling, granulation and sludge drying, solving two difficult problems of slag cooling and sludge drying, and greatly increasing the waste heat recycling rate of high-temperature slag.

Claims

1.-3. (canceled)

4. An apparatus for molten slaq cooling, granulation and sludge drying, comprising: a) A molten slag cooling treatment device having a cylinder structure, comprising: a propulsion mechanism provided on an inner wall thereof, a molten slag feeding hopper provided at an inlet thereof, and a slag discharge mechanism provided at an outlet thereof; wherein the molten slag cooling treatment device is provided with a first driving device configured to drive it to rotate; b) A plurality of steel balls, and a steel ball transporting device coupled to the inlet of the molten slag cooling treatment device; c) A high temperature steel ball chute, one end of which is coupled to the outlet of the molten slag cooling treatment device; and d) A sludge drying device having a cylinder structure, comprising: a propulsion mechanism provided on an inner wall thereof, a sludge transporting device provided at an inlet thereof, and a dry sludge discharge device provided at an outlet thereof, wherein the sludge drying device is provided with a second driving device configured to drive it to rotate; wherein the inlet of the sludge drying device is coupled to the other end of the high temperature steel ball chute.

5. The apparatus of claim 4, wherein the apparatus further comprises a low temperature steel ball chute, one end of which is coupled to the outlet of the sludge drying device, and the other end of which is coupled to a steel ball inlet of the steel ball transporting device.

6. The apparatus of claim 4, wherein the steel ball inlet of the steel ball transporting device is communicated with the outlet of the sludge drying device via the low temperature steel ball chute, and a steel ball outlet of the steel ball transporting device is coupled to the molten slag feeding hopper of the molten slag cooling treatment device, such that the molten slag cooling treatment device, the steel ball transporting device, and the sludge drying device are arranged in an end-to-end triangular configuration.

7. The apparatus of claim 4, wherein the steel ball transporting device is disposed with its outlet end oriented obliquely upward at an inclination angle of 25°-80°.

8. The apparatus of claim 4, wherein the steel ball transporting device has a cylinder structure and comprises a propulsion mechanism provided on an inner wall thereof, wherein the steel ball transporting device is provided with a third driving device configured to drive it to rotate.

9. The apparatus of claim 4, wherein the molten slag cooling treatment device and the sludge drying device are arranged in such a manner that an acute angle is formed therebetween.

10. The apparatus of claim 4, wherein the molten slag cooling treatment device is disposed horizontally, or disposed with its inlet end oriented obliquely downward at an inclination angle of 0°-45°.

11. The apparatus of claim 4, wherein the sludge drying device is disposed horizontally, or disposed with its outlet end oriented obliquely downward at an inclination angle of 0°-15°.

12. The apparatus of claim 4, wherein the slag discharge mechanism and the dry sludge discharge device are provided with a tail gas collection and discharge device.

13. The apparatus of claim 4, wherein the first driving device and the second driving device each comprise a ring gear disposed on the molten slag cooling treatment device or the sludge drying device, and a driving gear meshed with the ring gear, wherein the driving gear is disposed on an output end of a reducer coupled to a motor.

14. The apparatus of claim 8, wherein the third driving device comprises a ring gear disposed on the steel ball transporting device, and a driving gear meshed with the ring gear, wherein the driving gear is disposed on an output end of a reducer coupled to a motor.

15. The apparatus of claim 4, wherein the propulsion mechanism is a spiral shoveling plate.

16. The apparatus of claim 10, wherein the molten slag cooling treatment device is disposed horizontally, or disposed with its inlet end oriented obliquely downward at an inclination angle of 5°-15°.

17. The apparatus of claim 8, wherein the propulsion mechanism is a spiral shoveling plate.

18. A method for molten slag cooling, granulation and sludge drying, comprising steps of: 1) Mixing high temperature molten slag and steel balls at a weight ratio of 1:50-100 in a molten slag cooling treatment device, wherein the high temperature molten slag and steel balls are fully and evenly mixed and heat exchanged by tumbling the high temperature molten slag and steel balls, wherein the steel balls absorb heat from the high temperature molten slag, while the high temperature molten slag is gradually cooled and crushed by the steel balls to form granular slag having a particle diameter of ≤150 mm and a temperature of lower than 400° C.; wherein the steel balls having absorbed heat have a temperature of 200-400° C.; 2) Discharging the granular slag through a slag discharge mechanism, and discharging the steel balls having absorbed heat into a high temperature steel ball chute; 3) Transporting the steel balls having absorbed heat to a sludge drying device through the high temperature steel ball chute to mix with sludge infused into the sludge drying device, wherein the sludge drying device is driven by a driving device to rotate so that the sludge and steel balls in the sludge drying device tumble, and fully and evenly mix and exchange heat, whereby the sludge is dried by the steel balls having absorbed heat; wherein the steel balls and dried sludge are separated when a moisture content of the sludge reaches a set value; wherein the dried sludge is discharged through a dry sludge discharge device, and the cooled steel balls are discharged through an outlet; wherein a mass ratio of the steel balls to the infused sludge is 2-10:1.

19. The method of claim 18, wherein the cooled steel balls are transported and returned to the molten slag cooling treatment device, thereby forming a cyclic treatment process.

20. The method of claim 18, wherein an initial moisture content of the sludge is 30-95%, and a moisture content of the dried sludge is 3-10%.

21. A method for molten slag cooling, granulation and sludge drying is performed with the apparatus of claim 1.

Description

DESCRIPTION OF THE DRAWINGS

[0078] FIG. 1 is a schematic view illustrating the structure of an apparatus for integrated dry granulation of molten slag and drying of sludge according to the present disclosure.

[0079] FIG. 2 is a view in direction A in FIG. 1.

[0080] FIG. 3 is a view in direction B in FIG. 1.

[0081] FIG. 4 is a view in direction C in FIG. 1.

[0082] Reference numbers include: 1, molten slag cooling treatment device; 2, steel ball; 3, steel ball transporting device; 4, high temperature steel ball chute; 5, sludge drying device; 6, low temperature steel ball chute; 7, steel ball chute; 8, tail gas collection and discharge device; 9, supporting device; 11, 31, 51, propulsion mechanism; 12, molten slag feeding hopper; 13, slag discharge mechanism; 14, first driving device; 16, cold slag collection device; 17, cold slag bin; 18, dry sludge collector; 19, dried sludge bin; 52, sludge transporting device; 53, dry sludge discharge device; 54, second driving device; 32, third driving device; 100, high temperature slag; 200, sludge.

DETAILED DESCRIPTION

[0083] Referring to FIGS. 1-4, the apparatus for integrated dry granulation of molten slag and drying of sludge according to the present disclosure comprises: [0084] A molten slag cooling treatment device 1 having a cylinder structure, comprising: a propulsion mechanism 11 provided on an inner wall thereof, a molten slag feeding hopper 12 provided at an inlet thereof, and a slag discharge mechanism 13 provided at an outlet thereof; wherein the molten slag cooling treatment device 1 is provided with a first driving device 14 configured to drive it to rotate; [0085] A plurality of steel balls 2, and a steel ball transporting device 3 coupled to the inlet of the molten slag cooling treatment device 1; [0086] A high temperature steel ball chute 4, one end of which is coupled to the outlet of the molten slag cooling treatment device 1; [0087] A sludge drying device 5 having a cylinder structure, comprising: a propulsion mechanism 51 provided on an inner wall thereof, a sludge transporting device 52 provided at a sludge inlet, and a dry sludge discharge device 53 provided at an outlet, wherein the sludge drying device 5 is coupled to a second driving device 54 configured to drive it to rotate; wherein the inlet of the sludge drying device 5 is coupled to the other end of the high temperature steel ball chute 4.

[0088] Further, a steel ball inlet of the steel ball transporting device 3 is communicated with the outlet of the sludge drying device 5 via a low temperature steel ball chute 6, and a steel ball outlet of the steel ball transporting device 3 is coupled to the molten slag feeding hopper 12 of the molten slag cooling treatment device 1 via a steel ball chute 7, such that the molten slag cooling treatment device 1, the steel ball transporting device 3, and the sludge drying device 5 are arranged in an end-to-end triangular configuration.

[0089] Preferably, the steel ball transporting device 3 is disposed with its outlet end oriented obliquely upward at an inclination angle of 25°-80° relative to a horizontal plane.

[0090] Preferably, the steel ball transporting device 3 has a cylinder structure and comprises a propulsion mechanism 31 provided on an inner wall thereof, wherein the steel ball transporting device 3 is coupled to a third driving device 32 configured to drive it to rotate.

[0091] Preferably, the molten slag cooling treatment device 1 is disposed with its inlet end oriented obliquely downward at an inclination angle of 0°-45°, preferably 5°-15° relative to a horizontal plane.

[0092] Preferably, the sludge drying device 5 is disposed horizontally, or disposed with its outlet end oriented obliquely downward at an inclination angle of 0°-15° relative to a horizontal plane.

[0093] Preferably, the slag discharge mechanism 13 and the dry sludge discharge device 53 are provided with a tail gas collection and discharge device 8.

[0094] Preferably, the first driving device 14 and the second driving device 54 each comprise a ring gear disposed on the molten slag cooling treatment device or the sludge drying device, and a driving gear meshed with the ring gear, wherein the driving gear is disposed on an output end of a reducer coupled to a motor.

[0095] Preferably, the third driving device 32 comprises a ring gear disposed on the steel ball transporting device, and a driving gear meshed with the ring gear, wherein the driving gear is disposed on an output end of a reducer coupled to a motor.

[0096] Preferably, the propulsion mechanisms 11, 51, 31 each are a spiral shoveling plate.

[0097] Preferably, the molten slag cooling treatment device 1, the sludge drying device 5 and the steel ball transporting device 3 each are provided with supporting devices 9 at both ends.

[0098] Preferably, the slag discharge mechanism 13 is coupled to a cold slag collection device 16, and a cold slag bin 17 is provided below the cold slag collection device 16.

[0099] Preferably, the dry sludge discharge device 53 is coupled to a dry sludge collector 18, and a dried sludge bin 19 is provided below the dry sludge collector 18.

[0100] The integrated process for dry granulation of slag and drying of sludge according to the present disclosure comprises:

[0101] 1) Slag-Ball Mixing and Soaking

[0102] High temperature molten slag 100 and a plurality of steel balls 2 are first sent to a rotating molten slag cooling treatment device 1 through a slag feeding hopper 12 to fulfil slag-ball mixing. The high temperature molten slag 100 is gradually cooled and crushed by the steel balls 2, and transfers its heat to the steel balls 2. The high temperature molten slag 100 is gradually cooled and crushed by the steel balls to form granular slag having a particle diameter of ≤150 mm and a temperature of lower than 400° C. The granular slag is discharged through a slag discharge mechanism 13 at the tail of the molten slag cooling treatment device 1, collected by a cold slag collection device 16, and transferred to a cold slag bin 17 below for subsequent resource treatment and utilization. The high temperature steel balls 2 having absorbed heat continue to advance as the molten slag cooling treatment device 1 rotates, and are discharged to a high temperature steel ball chute 4. The weight ratio of the high temperature molten slag to the steel balls is 1:50-100, and the temperature of the steel balls having absorbed heat is 200-400° C.

[0103] 2) Sludge Drying

[0104] The high temperature steel balls 2 are transported to the sludge drying device 5 through the high temperature steel ball chute 4, and mixed at the inlet with the sludge 200 infused through a sludge transporting device 52. The mass ratio of the steel balls to the infused sludge is 2-10:1. The sludge drying device 5 rotates under the drive of a second driving device 54, so that the sludge 200 and the steel balls 2 in it tumble, and fully and evenly mix and exchange heat. The sludge 200 is dried by the high temperature steel balls 2. When the moisture content of the sludge 200 reaches a set value, the steel balls 2 are separated from the sludge 200. The sludge 200 is discharged through a dry sludge discharge device 53, collected by a dry sludge collector 18, and sent to a dried sludge bin 19 below for subsequent resource treatment and utilization. The cooled steel balls 2 are discharged through the outlet.

[0105] Further, the steel balls 2 discharged from the sludge drying device 5 enter a low temperature steel ball chute 6 along which the steel balls are transported to a steel ball transporting device 3. Under the driving action of gravity and a pushing mechanism 31, the steel balls 2 are discharged from an outlet of the steel ball transporting device 3, and enter the molten slag feeding hopper 12 of the slag cooling treatment device 1, forming a cyclic treatment process.

[0106] The process control parameters in the Examples of the present disclosure are listed in Table 1 in detail.

TABLE-US-00001 TABLE 1 Weight ratio Granular Temperature Weight Initial Moisture of high Molten slag Granular of steel ratio of moisture content temperature slag particle slag balls having steel balls content of of dried molten slag to temperature diameter temperature absorbed heat to infused sludge sludge No. steel balls ° C. mm ° C. ° C. sludge % % Ex. 1 1:50 1500 150 385 365 2:1 30 5.8 Ex. 2 1:60 1500 120 378 350 2:1 48 8.5 Ex. 3 1:70 1450 100 350 335 6:1 45 3.5 Ex. 4 1:75 1450 80 353 337 3:1 75 6.6 Ex. 5 1:80 1500 50 367 343 7:1 75 5.2 Ex. 6 1:85 1450 70 345 321 4:1 82 7.5 Ex. 7 1:90 1400 90 335 306 6:1 82 7.3 Ex. 8  1:100 1350 80 305 268 8:1 95 4.8