Mineral wool is a man-made fiber produced by using metallurgical slag as the main raw material. The production process includes: adjusting the composition of the molten hot slag liquid to meet the corresponding requirements, and then throwing the hot slag liquid through a centrifuge at a high speed to throw out the fibers, and the fibers are Collect, sort and solidify to obtain mineral wool board, felt and other products.
Hot slag liquid is usually obtained by melting cold metallurgical slag, coke and other auxiliary materials in a cupola. Considering the effective utilization of energy and resources in a circular economy, more and more people have thought of using the hot slag liquid formed by the metallurgical process to directly make cotton. In this way, two resources of by-product slag and thermal energy can be utilized at the same time. In the direct cotton production line using smelting hot slag liquid, the most critical equipment is the hot slag liquid holding furnace.
The role of the hot slag liquid holding furnace in the process of cotton production: ① normal fiber production. The temperature of the hot slag liquid of metallurgical by-products entering the holding furnace is generally lower than the value required for fiber production due to reasons such as release and transportation; ② Adjust the composition. According to different product requirements, such as the different acidity coefficients of granular cotton for external wall thermal insulation board and ceiling, it is necessary to adjust the slag composition. Completing the above two tasks requires thermal energy to heat up and keep warm.
Insufficiency of the current hot slag holding furnace lining
At present, the direct use of metallurgical hot slag liquid to directly make cotton has not been used for a long time in China. Many enterprises are in the early stage of industrialization, and few of them have realized industrialization. In practice, the operation effect of the hot slag liquid holding furnace is not ideal, mainly because the lining consumption is fast and the furnace age is short. As many as 10d, as few as 6~7d, which affects the efficiency and benefit of the entire cotton production line.
The working process of the hot slag holding furnace is as follows: every fixed time period, such as 2~4h, flows into the hot slag liquid from the slag inlet, and at the same time, the slag outlet continuously flows out in a certain amount. The slag liquid level in the holding furnace decreases continuously with the outflow time, and when it falls to a certain position, new slag liquid is replenished.
In short, in the production process, the inflow of slag liquid is intermittent, and the outflow of slag liquid is continuous. The technological process causes damage to the lining of the holding furnace: ①Mechanical damage: the frequent replenishment of new slag liquid causes strong scouring of the furnace lining; ② Thermal damage: When the new slag liquid is filled up, the furnace lining temperature rises, and when the slag liquid is emptied, the furnace lining The temperature decreases, thermal expansion and contraction cause thermal shock and damage to the furnace lining; ③Chemical etching: on the one hand, the hot molten slag reacts with the furnace lining more or less; Materials such as carbon bricks undergo a strong oxidation reaction and are lost.