Blast furnace self-baking charcoal brick, as the name suggests, is a masonry material used inside blast furnaces. It is a carbonaceous refractory made of high-quality anthracite, coke, graphite, etc. as the main raw materials, through crushing, screening, mixing, molding, roasting and other processes. Blast furnace self-baking charcoal bricks have the characteristics of high temperature resistance, thermal shock resistance, erosion resistance, low porosity, etc., and are widely used in the lining masonry of blast furnaces, which is of great significance for improving the service life of blast furnaces and reducing production costs.
1. The composition of the blast furnace self-baking charcoal brick.
The main raw materials of blast furnace self-baking charcoal bricks are anthracite, coke and graphite. Anthracite is the main component of carbon bricks, with high fixed carbon content and low volatile content, which can provide sufficient carbon sourceCoke is the binder of carbon bricks, which can bond various raw materials together to form a uniform brick body;Graphite is the lubricant of carbon bricks, which can reduce the porosity of carbon bricks and improve the compactness of carbon bricks. In addition, some auxiliary raw materials, such as limestone, ferrosilicon, etc., can also be added as needed to improve the performance of carbon bricks.
Second, the production process of blast furnace self-baking charcoal bricks.
The production process of blast furnace self-baking charcoal bricks mainly includes crushing, screening, mixing, forming, roasting and other links.
Crushing: The raw materials are coarsely crushed and finely crushed to make them reach a certain particle size requirement.
Screening: The crushed raw materials are graded by screening equipment to meet the requirements of different particle sizes.
Mixing: Mix raw materials with different particle sizes in a certain proportion to ensure the stable performance of carbon bricks.
Moulding: The mixed raw materials are molded to make carbon bricks of different shapes and sizes.
Roasting: The formed carbon brick is roasted at high temperature to make it undergo physical and chemical changes to form a carbon brick with certain strength and performance.
3. Performance characteristics of blast furnace self-baking carbon bricks.
High temperature resistance: Blast furnace self-baking charcoal bricks have high melting point and high temperature stability, and can maintain good structural stability and erosion resistance under high temperature conditions.
Thermal shock resistance: The blast furnace self-baking charcoal brick has good thermal shock resistance, which can maintain stability under the condition of temperature fluctuations inside the blast furnace, and reduce the generation and development of cracks.
Anti-erosion: Blast furnace self-baking charcoal bricks have good alkali and oxidation resistance, and can resist the erosion of molten fluids and gases inside the blast furnace.
Low porosity: The blast furnace self-baking charcoal brick has a very low porosity, which can reduce the heat loss and improve the thermal efficiency of the blast furnace.
Fourth, the application of blast furnace self-baking charcoal bricks.
Blast furnace self-baking charcoal bricks are widely used in the lining masonry of blast furnaces, including the bottom of the furnace, the furnace cylinder, the belly of the furnace, the waist and other parts. Due to its excellent performance characteristics, blast furnace self-baking charcoal bricks can effectively improve the service life of blast furnaces, reduce production costs and improve production efficiency. At the same time, blast furnace self-baking charcoal brick also has certain environmental significance, because it can reduce pollution to the environment and reduce energy consumption.
In a word, blast furnace self-baking charcoal brick is an important refractory material, which is of great significance for the masonry of blast furnace. With the development of blast furnace technology and the improvement of environmental protection requirements, the research and application of blast furnace self-baking charcoal bricks will receive wider attention and development.
Self-baking charcoal bricks are products made of high-temperature calcined anthracite as aggregate, calcined anthracite and coke mixed powder as fine powder, medium-temperature coal asphalt as binder, evenly kneaded at a certain temperature, and molded by high-frequency molding vibration, with external dimensions and specific physical and chemical properties. It has the characteristics of high temperature resistance, good thermal conductivity, high temperature strength, strong resistance to iron slag erosion, and low resistance.
Self-baking charcoal bricks have the following characteristics in production and use:
1) The production process is simple, the investment cost is low, and the construction is simple and easy
2) It has a regular shape and can be masonry into the required lining without precision machining
3) Roasting by the heat of the oven and blast furnace production can form a nearly seamless integral furnace lining;
4) During the roasting process (single-sided heating condition), the volatiles of coal tar asphalt move in a reverse direction, generate pyrolytic carbon in the pores of the matrix at the working hot end and fill the pores, so that the brick body "self" dense;
5) It can absorb the temperature stress generated when the furnace lining is heated up, and alleviate the damage of thermal stress to the furnace lining
6) Under the catalytic action of high-temperature slag iron and other media in the furnace, the heterogeneous stone boiling transformation is generated, which improves the thermal conductivity and chemical erosion resistance of the furnace lining, and makes the solidification isotherm of 1150 molten iron migrate to the furnace.
Due to the characteristics of self-baking charcoal bricks and the qualitative change in the furnace, the stability and durability of the furnace lining are finally improved, so that the self-baked carbon bricks can be widely used in small and medium-sized blast furnaces, and good technical and economic results have been obtained. The use of semi-graphite self-baked carbon bricks in large blast furnaces can reduce the molten iron melt index, improve thermal conductivity, improve alkali erosion resistance, enhance oxidation resistance, improve erosion and wear resistance, and reduce residual shrinkage.