Cement rotary kiln special refractory castable

Posted by adela li on November 17th, 2016

Rotary kiln is a special kiln in the dynamic work, mainly used for cement clinker, petroleum coke, magnesium dolomite, limestone, iron oxide magnetite, nickel iron laterite ore and non-ferrous metal sulfide ore calcination and roasting. Due to the special conditions, to a certain extent, the fire resistance

Material lining has a higher demand, the traditional refractory brick in the kiln is a serious challenge. According to the working characteristics of this type of kiln, developed a series of special rotary kiln refractory castable.

Rotary kiln with castable refractory can not be fired in addition to the direct use of common features, in many types of unshaped refractory production process is relatively simple, no special equipment. Many manufacturers of new dry process cement kiln production line ignition feeding production status

But the use of refractory castable are still on the issue, our company conducted a comparative analysis of the use of refractory castable made a summary of the situation.

1, pouring material configuration program
High-temperature low-cement refractory castable for kiln mouth, high-strength low-cement refractory castable for kiln mouth, high-strength low cement refractory castable for kiln tail smoke chamber and precalciner, Aluminum refractory castable, tertiary air duct with high aluminum low water

Mud refractories castable material, coal injection pipe with corundum quality coal injection pipe dedicated castable.

2, pouring material off phenomenon
It can be seen from the above, due to the unreasonable configuration of the reasons for the design, just put into operation in the rotary kiln more than a year to occur on a number of castable peeling accident, stop kiln failure rate. Mainly decomposition furnace and three times the intersection of air duct burned several times, decomposition furnace necking bad

, The three ducts fall off, three bursts in the head of the coal discharge pipe fall, the grate cooler low wall wear, kiln hood three burn through, kiln tail smoke chamber arches beam collapse.

3. Analysis of castable shedding
Changes in the original fuel, especially after the use of anthracite coal ash suddenly a lot of settlement, leading to the kiln tail smoke chamber slope, decomposition crust crust frequently, the need to manually use iron tools to clean up, inevitably cause refractory mechanical damage at the same time, into the kiln Raw material saturation

The corrosion resistance of the castables and the ability to resist oxidation and reduction of the atmosphere were greatly reduced by the infiltration of the liquid phase alkali salt, deterioration of the thermal shock resistance, thermal shock resistance, alkali erosion resistance and reduction atmosphere. Especially in the more frequent use of the kiln to open and stop, greatly reduced life expectancy

Short, with clinker dust erosion, erosion, and the expansion of hot and cold kiln temperature, resulting in kiln hood, tertiary air duct, grate cooler and other pouring material failure occurred.

The traditional cement basic refractories castable, due to the higher amount of cement, can get enough room temperature strength. However, the crystalline transformation of the cement at moderate temperature will lead to a significant decrease in strength, leading to a decrease in the high temperature strength and corrosion resistance of the material.

Quenching and exacerbating the frequent accidents of refractories, a large number of literature that the basic coefficient of thermal expansion, in the process of heating a huge thermal stress, so the temperature is slow drying kiln, the expansion of the kiln system expansion of supplementary refractory play a compensatory role, which Is how to use

Good refractory material is the key. But in actual production is difficult to accept a long time drying kiln, found the problem when they directly Kai high temperature fan for rapid cooling kiln temperature. Repair in order to grab production, but also requires rapid heating, which is damaged for the laying of refractory material

pen.

4, pouring material fall off measures
Different grades of refractory castables are selected for different parts of precalcining kiln system. Decomposing furnace shrinkage is made of anti-crusting refractory castable, kiln hood is used in steel fiber high aluminum refractory castable, grate cooler low wall is easy to wear and wear high strength mullite wear

Castable, corundum castable used in the pulverized coal pipe burst on the easy use of high-strength steel to switch to high-alumina wear-resistant refractory castable, when repaired with high-alumina refractory castable rapid repair.

As the castable used now is not crust, not only reduces the intensity of the inspection work, but also improve the rotary kiln Zhiliao clean-up decomposition crusher crust crushing operation time, greatly enhancing the production efficiency.