Hebei refractory manufacturers today specially for the production of cement kiln needs to provide a piece of information for better service, this article will mainly describe the promotion of customized refractory amorphous refractories in China to promote the application of amorphous refractories need to focus on improving the performance of which aspects of the application of amorphous refractories.
1. Good corrosion resistance and corrosion resistance.
The continuous application of new technology and equipment in cement industry has put forward higher requirements for refractory lining of thermal equipment. In recent years, the new fourth generation grate cooler has been widely used in cement kiln production, the fourth generation grate cooler energy saving, consumption reduction, high cooling efficiency; the movement of the grate bed is much larger than the third generation, in this part of the lining will be high temperature material pulled out many grooves, wear and tear serious. The abrasion of amorphous refractories is serious, which requires that the linings in contact with them have high abrasion resistance.
In the whole cement rotary kiln calcination system, the use of alternative fuels or inferior fuels will have many additional effects on the refractory lining.
Overseas, with the development of cement technology, petroleum coke, plastics, animal waste, sewage sludge, solvents, organic wastes and other secondary fuels or alternative fuels are used, which is indeed a technological progress, but also accompanied by some negative elements, such as chlorine, sulfur, alkali metals, bromine, iodine, etc. into the combustion system. The concentration of volatile components increased, resulting in increased corrosion and high temperature chemical erosion.
Especially, the increasing use of alternative fuels and inferior fuels, the continuous development of refuse incineration kilns, the resistance of unshaped refractory lining of cement rotary kiln system and some thermal equipment to high temperature load and high temperature chemical erosion have become the focus of attention.
Volatile compounds, such as chlorine, sulfur and alkali, react in high-temperature gases in the kiln to form compounds containing sulfates and chlorides. These gaseous or liquid compounds invade the lining structure after heating through working linings, expansion joints or cracks, and usually crystallize between 750 and 1100 degrees Celsius. In different temperature regions of cement kiln system, the wear-resistant layer and insulation layer will be corroded by chloride (KCl, NaCl) and alkali compounds (K2CO3, K2SO4, Na2SO4) in varying degrees, and the metal anchorage parts will be corroded by high temperature gas or sulfate and hydrochloric acid.
For the refractory lining technology of cement production, we must consider not only the corrosion of water or liquid, but also the chemical corrosion of high temperature gas, and the corrosion of sulfur leaching and chloride ions on amorphous refractories. Production practice shows that some sulphur and chlorine deposits have been deposited inside the cement rotary kiln.
2. Good baking performance.
With the wide application of low cement castable, the spalling and bursting of this kind of castable in the process of drying and heating appear simultaneously. During heating and baking, a large amount of steam pressure is generated inside the castable, and spalling and bursting occur when the steam pressure exceeds the tensile strength of the castable. At present, to solve the problem of explosion cracking of castable, one method is to adopt reasonable drying and baking system, the other is to add anti-explosion agent in the castable to increase the permeability of hardened body and reduce the maximum steam pressure inside the castable. Commonly used additives are metal aluminum powder, aluminum lactate and organic fiber.
Practical application shows that the performance and application effect of customized refractories depend largely on their construction and baking effect. Nowadays, the development of safe and efficient baking technology has attracted more and more attention. It seems that the research and development of unshaped refractories with fast curing, rapid baking and even no baking are very important. Very necessary. Especially for the renovation of the old cement plant, there is a new unshaped lining in some renovated equipment in the cement kiln system. When the new and old lining coexist, the steam pressure inside the castable exceeds the tensile strength of the castable due to the inadequate maintenance and baking of the new lining, which leads to frequent burst of the castable lining and affects the production. Proceed normally. Fig. 3 shows the explosion of amorphous refractories which are eager to feed after 10 hours of baking in an old factory.
Finally, Hebei refractory construction factory also said that the construction, maintenance, baking, maintenance of amorphous refractories is difficult, directly affecting the degree of its acceptance by users, so you must pay attention to peers, have time to go to Guoliang special refractory website, pay attention to the latest relevant knowledge of refractory bricks.
What are the properties of custom refractory refractory materials used in cement kilns?