Blast furnace heavy slag heat-preservation ceramsite and preparation method thereof

The invention discloses a blast furnace heavy slag heat-preservation ceramsite and a preparation method thereof, wherein the ceramsite comprises the following raw materials in part by weight: 55-75 parts of blast furnace heavy slag tailings, 15-25 parts of admixture, 1-25 parts of binder, 1-2 parts of expanding agent and 8-15 parts of water; the admixture is selected from steel slag powder, water granulated slag powder and manganese slag powder. The preparation method comprises the following steps: mixing blast furnace heavy slag tailings, admixture, binder and expanding agent uniformly, and grinding to obtain mixed powders; adding water to the mixed powders; stirring to obtain a mixture; pelletizing to obtain spherical granular raw materials, adding the obtained spherical granular raw materials to a drying system and then to a rotary kiln, roasting at a high temperature for 20-45 minutes, and cooling to obtain the blast furnace heavy slag heat-preservation ceramsite. According to the invention, a large amount of blast furnace heavy slag is taken as a part of raw materials for synthesizing the ceramsite, so that the blast furnace heavy slag is recycled, the production cost of ceramsite for building blocks, and meanwhile, the blast furnace heavy slag is utilized as resources.