Cement Kiln

Introduction

Cement kiln, just as its name implies, it is known for its capability to deal with cement. It is a device for bedding for dry and wet cement clinker production. Cement kiln can also be widely applied in other sectors like metallurgy, chemical engineering, building refractory, environmental protection, etc. Cement kiln is composed of the barrel, supporting device, a support device with baffle wheels, gearing, active kiln head hood, kiln end sealing device, coal jet pipe device and so on.

Cement Kiln Design Principle

Cement Kiln Principles

Cement rotary kiln turns into micro running under high temperature. The maintain of attachment devices and the level of the thermal system is closely related to cement kiln’s safety and efficiency. The key points of caring and maintaining gearing are to checking lubrication, running status, dynamic detection and meshing precision between large and small gears. Installation accuracy of supporting device keep rotary kiln safe and smooth. Then, pay attention to the rational distribution of stay wheels’ bearing weight, layout form of riding wheels, hydraulic gear’s upstream and downriver pressure and time. The quality of stealing device directly affects the rotary kiln’s quality of the thermal system and operating cost. In one word, keeping routine maintenance and data analysis benefits the management of devices.

Cement Kiln Structure

design features of cement kiln
design features of cement kiln
cement kiln plant

Cement kiln is an important device for the dry and wet cement production line. Cement kiln is mainly formed by barrel, gearing, roller support device, stop wheel support device, kiln lining, kiln tail seal, kiln head hood and fuel plant.

Cement Kiln Classification

Classificated By Mode Of Heating

Internal Heating Cement Kiln

Cement kiln’s material of internal heating-type directly contacts with flame and smoke. So, the inside wall of kiln is laid by refractory bricks. Head and tail cover lining is made from wear-resisting, casting material.  There is a flexible seal between the head and tail-cover and kiln, which prevents a kiln from raising dust and leaking.

External Heating Cement Rotary Kiln

Cement kiln’s material of external heating-type doesn’t directly contact with flame and smoke. Heat source exists between heating furnace and kiln,  heating material conducting heat through heat resistant steel cylinder wall. The lining of heating furnace is made from refractory fiber, which helps cement kiln’s energy-saving and cost-reducing.

Classified By Dry Kiln And Wet Kiln

Dry Cement Kiln

Cement kiln puts raw material into kiln tail, raw material turning itself into cement clinker after a series of physical and chemical reaction because of kiln’s tilt placement and its rotary capability. Put cement clinker into the cooling machine after it ejected from kiln head hood. Dry rotary kiln makes the raw material into raw powder, whose water content is less than one percent. The advantage is that it saves more energy than a wet rotary kiln. The disadvantage is that it may happen that ingredient in mixed material is uneven.

Wet Cement Kiln

Cement kiln turning raw into a slurry, whose water content is from 32 percent to 40 percent. The advantage of wet rotary kiln is that the good liquidity of slurry makes better evenness leading to a higher quality of clinker.

Kiln Operation Parameters

Lattice model technical parameters The main reducer main motor supporting number
weight(t)
rotate speed (r/min)yield (t/h)inclination (%) model model power (kw)rotate speed(r/min)
φ1.6 X 360.26-2.630.6-1.53ZL75048.57YCT250-4B221320/132347.5
φ2.5 × 500.62-1.867.5-153.5ZS145-7100YCT355-4A551340/440 3167.5
φ3 × 480.47-1.4015-203.5ZS145-7100YCT355-4B751340/6003237
φ3.2 × 500.398-3.97520-503.5ZL130-1640ZSN4-280-11B1901000 3263
φ4 × 600.396-3.9632-1053.5ZSY630-35.535.5ZSN-355-0923151000 3487.5

Cement Kiln Installation And Maintenance

structure of cement kiln
structure of cement kiln

Cement Kiln Installation And Debugging

  • Be familiar with a blueprint of the cement kiln. Comprehend cement rotary kiln’s concrete parameters, sub-units’ exact location and basic line’s benchmark through the blueprint. Grasp the information about the transport route, working site, tool room, and temporary power supply through the layout chart.
  • Select good cement kiln hoisting equipment and transportation equipment. The device on the cement kiln-production line is generally with large size and heavyweight, so the necessary hoisting equipment and transportation equipment should at least be with a broad-scale. The selection, usage, maintenance of other tools such as steel wire rope, hemp rope and fixture should be in accordance with relevant provision. Fuel, cutter and welding tools also should be prepared to make sure the success of the installation.
  • Require for professional for cement kiln. Cement rotary kiln has a short construction period and more work high above the ground because process equipment is at height. So, the characteristic of the installation of cement kiln is difficult and dangerous. That requires constructors should have fit bodies, the wide-scale of knowledge, skilled technology and the ability to adapt to local conditions.
  • Install a cement kiln. The specific installation steps are as follows:

1) Construction preparation in a cement kiln. To make sure the smooth of installation, the buyer should check the equipment according to a blueprint, revise the sub-quality product, remove sundries then build a hanger and delivery it from storage. The outbound sequence should be anchor bolt, wheelset, kiln hood, cylinder, wheel, retaining wheel, spring plate, large gear, gear cover, gear, reducer, engine, auxiliary drive, smoke chamber,  kiln head hood, kiln tail, sealing device, burner, unloading device and other accessories.

2) Lifting and aligning in a cement kiln. The order of lifting and aligning is steel base first, kiln second.

3) Soldering in a cement kiln. A cement kiln generally uses manual welding and automatic submerged arc welding, followed with a soldering –quality check. Then kiln hood, sealing device, cooling system, and the lubricating system should be installed. Then proceed with the basic secondary grouting. Finally, the no-load debugging and test run should be implemented.

4) Laying masonry refractory in a cement kiln. After the success of the no-load test run, to guarantee the rigidity and intensity of cement rotary kiln, different types of refractory bricks should be laid inside the kiln. So it can keep kiln from burning down by high temperature or wearing and tearing by material flow.

shell of cement kiln
shell of cement kiln
entity of cement kiln
entity of cement kiln
  • Debugging in a cement kiln. After the installation,  check whether the technical indicators are qualified or not. Buyers should inspect the whole cement rotary kiln and its subsidiary facilities before any debugging. Details about debugging are below:

1) Make sure all fasteners are tightened firmly in a cement kiln. Clean up all sundries inside or outside the kiln, above or below the basement, especially those between gears or between wheel band and tugs.

2) Guarantee lubricating cold hydraulic system doesn’t leak in cement kiln meanwhile valves are flexible and reliable. Make sure the oil’s quantity, pressure, temperature, and flow can meet the designed requirements.

3) Check out indicators in cement kiln and the direction of motor rotation.

4) Make sure that in cement kiln gearing doesn’t have abnormal noise and large and small gears have normal meshing.

5) Assure the contact length in cement kiln between wheel band and tugs is no less than 70 percent.

6) Exclude hidden danger in cement kiln about loose components.

Cement Kiln Maintenance

Cement kiln’s maintenance can be divided into overhaul, medium repair, and minor repair according to different workload. The most important repairs are a medium and minor repair. Maintenance should be carried out during the time when kiln lining is replaced, but it should be done quickly(from 8 to 12 hours). Overhaul needs a lot of time to replace all wear and tear parts, so do check and adjust the whole kiln.