Home >> Business >> Projects
Active Lime Rotary Kiln Projects

2016-03-09_134942

    Kiln

Active lime rotary kiln is composed of cylinder, gears, support device, kiln liner and kiln tail sealing equipment, hood of kiln head and alkene material device etc..Active Lime rotary kiln as a heating device is a high-quality steel processed, is supported on the support device by tyer, and there is hydraulic pressure catch wheel on the first or some gear in order to control the turning of cylinder.Gearing gyrate according to process-required rotating speed by ring gear in the middle of cylinder.
Because of the need of installation or maintenance, the bigger Active lime rotary kiln has auxiliary gears, which makes cylinder gyrate more slowly. To prevent cold air come in and dust overflow, the reliable kiln tail and hed sealing equipment are installed on feed and discharge end. The most common are Cement clinker Rotary kiln, etc., more models to choose.

Feature of active lime rotary kiln:
1. Cylinder tyer bolster: lower bolster has three types: fixed, zoom and floating. The structure has simple replacement that is convenient and won't hurt cylinder.
2. Gears:single or double. Control the rotating speed by blucher, DE machine and frequency variable motor. Reliable energy-saving, and efficient.
3. Sealing equipment:there are many kinds for choice according to kiln models .
4. Spring edge sealing, graphite block sealing and combination for above. The feather is adaptive for cylinder rotating and swing. And sealing effect is very good.
5. Support device:advanced shaft structure, automatic temperature measuring device and electrical heating.

Rotary kiln design should meet the following requirements:
1, The specification of the rotary kiln should meet the demand of burning system output and it should be determined comprehensively combining the raw materials or fuel condition and the configuration situation of the preheater, decomposition furnace and the cooling machine.
2, The proportion of preheater kiln and pre-decomposing furnace(L/D) had better to be 11-16.
3, The slope of preheater and decomposition furnace should be 3.5%-3.5%; In the terms of rotation speed, the decomposition furnace should be 3.0-3.5 r/min and the preheater should be 2.0-2.5 r/min. The speed changing range should be1:10.
4, The cooling of rotary kiln burned into cylinder should adopt forced air cooling.
5, The main motor of rotary kiln should adopt stepless variable speed motor and should be installed auxiliary transmission and emergency power supply.

Working principle of active lime rotary kiln:
The limestone is 1150 degrees Celsius in the preheater kiln gas heated to 900 degrees Celsius, about 30% decomposition,and then the hydraulic push the push rod into rotary kiln. The limestone in rotary kiln roasts decomposition theory for CaO and CO2. Decomposition generates into the cooler lime and will be cooled in the cold air cooling to 100 degree Celsius eduction. The heat to 600 degrees Celsius heat of air into the kiln and the mixed fuel gas. The cold wind confirmed by waste gas again into the bag filter induced fan, then the drained to the chimney. Discharge of the cooler the lime vibrating feeder, chain conveyor and fight a pattern lift machine and belt into the lime library. According to the needs of user to determine whether screening process classification.

    Preheater without pushing rod

201510271411148564
Main parameter


Capacity
(t/d)

150

200

250

300

350

400

500

600

800

Kiln
(ӡm)

2.540

2.842

3.046

3.346

3.554

3.656

3.858

4.060

4.364

Cooler

2.83.6

2.84.0

3.0
4.0

3.2
4.0

3.4
4.4

3.8
4.4

4.2
4.4

4.4
4.4

4.6
4.5

Heat consumption
(kj/kgCaO)

5300/
5000

5300/
5000

5300/
5000

5300/
5000

5225

5225

5100

5100

4810

Sintered temperature()

1350/
1250

1350/
1250

1350/
1250

1350/
1250

1300

1300

1300

1300

1300

Technical Comparison


No.

Part Name

Vertical preheater with pushing rod

Vertical preheater without pushing rod

1

The technology resource

Europe the end of 1970’s

Patent in 2005

2

Discharge method

So many preheating room, hydraulic pushing rod, discharging periodically and intermittently, inside the bridge always under high temperature and pressure environment, easy for damage. The hydraulic pushing rod block the material easily, and bad seal.

Through heat-resistant feeder, the materials discharging continuously, so the exhaust gas resistant is small, no the trouble of bridge, no block, no leakage.

3

The outside dimension

Large

Small

4

Efficient preheating height

Approx. 3000mm, the material column height cannot be adjusted.

Similar with the preheating zone of vertical lime kiln, can reach more than 6000mm, and the material column height can be adjusted according to lime size, the temperature of the top exhaust gas, and system resistant.

5

The Efficient preheating storage capacity

43m3

117m3

6

The preheating time in preheater

130-150 mins

280-320 mins, totally preheater

7

The temperature of exhaust gas at the top of preheater after heat exchanging

380, low heat efficiency

180-220, high heat efficiency

8

The connection section between kiln and preheater

The efficient section of transfer channel is 2.01m2, due to small section, so resistant is large.

The efficient section is 4.52m2, so resistant is small.

9

Mechanical structure

Complex, including so many hydraulic and high temperature parts, easy for damage, and difficult for maintenance

Easy, no hydraulic part, long working life, easy for maintenance.

10

Refractories

Large quantity, many types, difficult for construction and maintenance, easy for damage

Easy structure, small quantity, little type, low cost, long operation time

11

CO2 concentration of tail gas

low

High, helpful to recycle CO, for example light calcium carbonate

12

Investment cost

High

Lower 30% than pushing rod preheater

13

Exhaust gas dedusting equipment

Due to high temperature (380), Before dedusting, cooler or mixed cooled air device shall be necessary to reduce the temperature of exhaust gas. After add mixed cooled air, the requirement of dedustor will be increased, and investment cost is also increased.

No need cooler, no need mixed cooling air, dedustor with lower than 30% capacity can be adopted.

14

Fan

Normally heat resistant fan shall be adopted, large capacity fan shall be adopted after adding mixed cooling air, and high voltage, power and load.

Normal middle voltage fan can be adopted, no need mixed cooling air, matched fan capacity can be lower 30%.

15

Market using time

20 years

8 years