Calcium oxide pellets with high thermal shock resistance and preparation method thereof

Abstract

The invention discloses a high-thermal-shock-resistance calcium oxide pellet and a preparation method thereof. The preparation method comprises the following steps: ball-milling carbide slag powder with 91.0-94.0% of Ca(OH)2 until the particle size is 60.0-150.0 mu m; adding 5.0-15.0% of H2O as a binder into the ball-milled powder, and uniformly mixing the obtained product; carrying out compression molding on the uniformly mixed powder at a molding pressure of 100.0-350.0 kgf / cm<2>, and then carrying out pressure maintaining for 0.5-3.0 min; drying the obtained product for 10.0-24.0 h; calcining the dried blank to 450.0-650.0 DEG C under an atmosphere with a CO2 concentration of 10.0-25.0%, and maintaining a constant temperature for 15.0-45.0 min; and calcining the obtained product for 90.0-120.0 min at a temperature of 900.0-1150.0 DEG C, and then carrying out furnace cooling. The strength of the calcium oxide pellet prepared according to the invention is reduced by 6.0-25.0% under the conditions that the difference between the temperature of the calcium oxide pellet and the room temperature is 500.0-1100.0 DEG C and the number of hot and cold cycles is 5.0-10.0. The method disclosed by the invention improves the thermal shock resistance of calcium oxide pellets in two stages of an application process; after being calcining in a rotary kiln, the calcium oxide pellet is subjected to quick cooling impact from 1100-1200 DEG C to 100-200 DEG C; and when being put into a calcium carbide furnace, the calcium oxide pellet is subjected to quick heating impact at a temperature of 1000.0 DEG C. Meanwhile, according to the invention, carbide slag is efficiently dealt, therefore, high environmental and economic benefits are obtained.

Description

technical field [0001] The invention relates to the technical field of resource utilization of bulk industrial solid waste, and relates to the preparation of calcium oxide pellets with high thermal shock resistance by using calcium carbide slag and a preparation method thereof. Background technique [0002] Carbide slag is a kind of Ca(OH) discharged during the production of acetylene from PVC by calcium carbide method. 2 Industrial waste that is the main component and difficult to digest. Ca(OH) 2 The content can reach 80.0-90.0%, which has great potential resource reuse value. It can be separated and removed, reshaped and sintered to produce calcium oxide, which can be recycled and reused as calcium carbide raw material for calcium carbide production. [0003] In the production of calcium carbide, the use of calcium oxide pellets as the raw material for calcium carbide production is more convenient than powdered calcium oxide to discharge the product CO and promote the r...

AI Technical Summary

Problems solved by technology

[0006] The technical problem solved by the invention: overcomes the deficiencies of the prior art, and aims at the technical problem that calcium oxide pellets have poor thermal shock resistance and are prone to bursting and pulverization when subjected to thermal shock in an alternating temperature field, and provide a high thermal shock resistance Calcium oxide pellets and preparation method, the control mechanism of the present invention is to improve the thermal conductivity of calcium oxide pellets by changing the calcined porous calcium oxide pellet structure: pore structure, porosity, and pore distribution, thereby improving the heat resistance of the pellets Vibration

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