-
ProjectProducts have been widely used in steel, carbon, glass, cement, coking, building materials, non-ferrous and other industries, to meet the requirements of a variety of high-temperature furnace.
-
ProductsThe company's main products are clay bricks, high alumina bricks, dense clay bricks, magnesia carbon bricks, high-strength insulation bricks. Special products include sintered corundum brick, corundum mullite brick, chrome corundum brick, etc., as well as various amorphous refractory materials and various refractory clay.
-
AboutThe company started from refractory raw materials, in line with the business policy of integrity and win-win, customer first, relying on its own funds, rolling development, and has now developed into a modern refractory enterprise integrating scientific research, development, production and service.
-
NewsProducts sell well in 31 domestic provinces and autonomous regions, and exported to Southeast Asia and other countries
-
ContactIn case of product quality problems during the warranty period, we guarantee to deal with them in a timely manner. After the expiration of the warranty, we still provide after-sales service, only charge for materials. We promise to reply within 24 hours after receiving the call and arrive at the scene within 3 days.
- zzstgs@126.com
NEWS CENTER
Lime kiln refractory brick fall-off reason
Release time:
Jan 01,2024
Lime kiln refractory brick (vertical kiln) selection principle is to resist alkali strong, dense strength good refractory brick, refractory brick with strong resistance to shedding. Many lime kiln refractory brick user reaction brick phenomenon occurs frequently.
Lime kiln refractory brick (vertical kiln) selection principle is to resist alkali strong, dense strength good refractory brick, refractory brick with strong resistance to shedding. Many lime kiln refractory brick user reaction brick phenomenon occurs frequently.
Here, I say two aspects. One is the choice of refractory bricks and the other is the masonry of lime kiln stoves. The mortar joint of refractory brick is the weak link after the furnace wall is built. When the furnace is built, the porosity of refractory brick masonry is large, the gap of brick masonry is large, alkali metal oxide, carbon precipitation reaction, etc. create the reaction site. The excessive development of edge airflow during operation will cause the temperature of the working hot surface of the furnace wall to be too high, creating conditions for the temperature effect and causing the brickwork to peel off prematurely.
The series of reactants formed by alkali metal oxides and mullite components in refractory bricks also cause volume expansion. There are two sources of these alkali metal oxides, one from fuel and the other from refractory materials themselves. These alkali metal oxides react with SiO2 in the refractory bricks to form compounds with low melting temperature, forming furnace nodules and causing damage to the furnace lining. Alkali metal oxides react with mullite trialuminosilica (3Al2O3.2SiO2) in refractory bricks to form potassium nepheline (K2O.Al2O3.2SiO2) leucite (K2O.Al2O3.4SiO2), accompanied by a volume expansion of 30% ~ 50%, while the melting temperature of potassium nepheline is about 1100 degrees Celsius, which seriously affects the refractoriness of refractory materials. The consequence is the stripping of the furnace lining. The heating zone is used to make castable to ensure that the temperature is uniform at the lower and upper parts and increase the steam temperature in the furnace tube. Refractory research department research: alkali metal damage is the main reason for the damage of brick lining, which accounts for about 40% of the damage. It is very important to remove iron and alkali from refractory raw materials. Iron removal is relatively simple, but it is difficult to remove alkali impurities K2O/NA2O/R2O. R2O is short for valence oxide. The grasp of this alkali metal oxide impurity depends on the raw material.
02. Thermal Stress Destruction
The temperature of the working face of refractory brick is close to the temperature of the edge gas flow, and the temperature of the working face is close to 1400, while the temperature of refractory brick is low, and the temperature difference between the two is above 400 degrees, so great thermal stress is generated in the brick lining, which is as high as 40MPa, so refractory materials with high thermal conductivity must be selected. The expansion formed by the thermal stress generated by the refractory brick heat moves like cold at high temperature, causing the furnace wall to easily form annular cracks. The requirement of refractory brick lining is that the side is hot and the refractory brick with high thermal conductivity must be selected because of the cold of steel shell and thermal insulation material.
顺通耐材
Address: Pingmo Town, Xinmi City, Henan Province
Telephone:0086371-85811678
E-mail: zzstgs@126.com
Copyright©2024 Zhengzhou Shuntong New Refractory Co., Ltd.