Problems in the reuse of waste refractory in China

       1.Lack of awareness

       At present, in some enterprises, simple workshop-type production is used, and the products are relatively simple. The wholesale of magnesium carbon bricks has affected the development of enterprises. All companies only pay attention to the purchase of raw materials, but they do not pay attention to discarded waste refractory materials, and there are still some misunderstandings. For example, the use of waste materials will have an impact on the quality of the product. Further awareness-raising is needed.

       2. Lack of related research technology

       In the current development of our country, the use of waste refractory started relatively late. Although some companies such as Panzhihua Iron and Steel and Baosteel have made some progress in the related utilization in recent years, the depth and breadth of research still exists. There are some shortcomings, and the overall utilization rate is relatively low. For example, the products are simply made into skateboards, magnesium bricks, aluminum-magnesium-carbon bricks, etc., but the quality control of the manufacturing process still needs to be further improved.

       3.Lack of reasonable classification

       In some enterprises, a site is built specifically for waste refractory materials, and various materials are stacked together. However, due to the different degrees of burns and different properties of some production, this will affect the later processing efficiency, and also Will make the utilization of waste refractory material can not meet high requirements.

       Recycling methods of waste refractories

       1.Direct use method

       Among disused refractory materials, they are directly used without being processed after dismantling. This method is called direct utilization method. For the layers and some less important locations, even after the liquid metal container is used, the damage caused is relatively Small, and even some refractory materials have no obvious changes. Therefore, these materials can be directly used in places where the safety requirements are relatively low or not the main location. With this method, there are relatively few varieties of refractory materials that can be implemented, but they can achieve the purpose of making the best use of them and minimize the occurrence of waste problems.

       2, primary use

       After a simple selection and crushing process, the waste refractory is made into different granules for use. This method is called the primary use method, which greatly reduces the quality of the product, and also solves environmental protection problems. The emergence of environmental pollution problems.

       3.Intermediate usage

       Based on the primary use method, the physical and chemical processing is further used to treat the waste refractory material, so that the level of the refractory material and the original material is closer. For example, after disposing of an abandoned skateboard and using it as a raw material for a skateboard, the skateboard produced is the same as the new one.

       4.Advanced usage

       Based on the principle of the synthesis of new materials, after pulverization processing, the following advanced methods of use can be used: 01 After adding some materials to it, use the high-temperature physical and chemical principles to synthesize new materials; 02 using this as raw materials Extraction of pure substances, such as metal chromium obtained by purification and reaction in high-chromium bricks, may have a very great value; 03 will process them into micro-powder or nano-powder. In current use, the first two methods are more common.

       Classification and utilization of waste refractories

       1, waste magnesium carbon brick

       After the waste magnesia carbon brick is recovered, it can be directly used and added to the magnesia carbon brick mixture used on the free surface of the ladle slag line, the proportion is 30% to 50%. All properties of the waste magnesium carbon bricks recovered before and after utilization are greater than the standard indicators. Therefore, recycling of magnesia-carbon bricks is completely feasible.

       2, waste aluminum magnesium carbon brick

       In the process of producing aluminum-magnesium-carbon bricks of the same material, waste aluminum-magnesium-carbon bricks can be appropriately added, and the aluminum-magnesium-carbon bricks can be broken into fine powder, which can produce refractory of the same material. Mud, which can be used in the masonry of aluminum-magnesium-carbon bricks.

       3, waste aluminum silicon carbide brick

       After the waste aluminum silicon carbide bricks are broken, the same material is used to produce refractory mud, which is used to build aluminum silicon carbide bricks. Part of the broken particles can be used to produce aluminum silicon carbide amorphous refractory materials, such as slag trench ramming material, slag trench pouring material and slag iron trench cover used in the front of the blast furnace.

       4, waste silicon brick, magnesia-chrome brick

       After crushing the ditch trench castable and the waste magnesium brick, an appropriate amount is added to the raw material of the magnesium-chrome brick and the raw material of the magnesium brick, and the raw material of the magnesium slag weir can also be added appropriately. Production of refractory mud.

       5. Waste high alumina brick

       The waste high-alumina bricks can be processed into fine powders to produce refractory mud. For granular materials, they can be produced in various plastics with different temperatures, such as those used in ladle caps. The castables are plastics that need to be applied in various repairs.

       Classification and Utilization of Waste Refractories

       In terms of material blending methods, waste refractory materials have been gradually applied in various materials, and all of them have been used in some types of waste refractory materials. In addition, the application of recycled dense refractory aggregates has also made relatively great progress. In particular, the use of chemical reagents to separate recycled aggregates has greatly increased the scope of application of waste refractory materials. At present, there are two main ways to comprehensively utilize waste refractory materials: machine downgrade use, repair use, and simple specification granular material utilization. Through research and analysis on the homogenization technology, separation technology and purification technology, some or all of the recycled materials can be replaced by genuine particles, thereby increasing the comprehensive utilization rate and increasing the added value of the product. At the same time, in-depth research on the recycling of high-end waste refractory materials should be carried out, so that the application range of waste refractory materials is more extensive.