Method for strengthening performance of complex-phase refractory material by pre-calcining-sintering microwave two-step method

Abstract

The invention discloses a method for strengthening the performance of a complex-phase refractory material by a pre-calcination sintering microwave two-step method. The method comprises the following steps of: step 1, mixing ferronickel slag, magnesite clinker and chromium trioxide, carrying out ball milling to obtain a mixture, adding a magnesium chloride solution into the mixture, carrying out compression molding to obtain green pellets, and drying the green pellets, putting the dried green pellets into a microwave reactor, and pre-calcining the green pellets for 5-40 minutes at the temperature of 1100-1250 DEG C to obtain a pre-calcined blank; and 2, further performing microwave sintering on the pre-calcined blank obtained in the step 1 so as to obtain the complex-phase refractory material, the temperature of the microwave sintering ranging from 1,300 DEG C to 1,350 DEG C, and the temperature time of the microwave sintering is shorter than or equal to 20 min. With the method adopted,the high-performance complex-phase refractory material with the compressive strength of 183.4 to 206.6 MPa, the refractoriness of 1845 to 1873 DEG C, the volume density of 3.16 to 3.61 g / cm <3> and the apparent porosity of 1.2 to 1.7 percent is obtained. The method has the advantages of high resource utilization rate, high product additional value, low production cost, environmental friendliness,simple process and the like.

Description

technical field [0001] The invention belongs to the field of refractory materials, and in particular relates to a method for strengthening the performance of composite refractory materials by a precalcination-sintering microwave two-step method. Background technique [0002] Ferronickel slag is industrial solid waste slag discharged during the smelting process of nickel-iron alloy, and its discharge is affected by factors such as raw material type and treatment process. According to reports, an average of 6-16 tons of ferronickel slag is discharged for every ton of nickel alloy produced. With the rapid development of the stainless steel industry, ferronickel slag has become the fourth largest industrial smelting slag after iron slag, steel slag and red mud. At present, the stockpile of ferronickel slag in China is as high as 200 million tons, and the annual discharge is growing rapidly at 40 million tons. More than 90% of the slag is disposed of in stockpiles and landfills...

AI Technical Summary

Problems solved by technology

However, excessive volume expansion will inevitably occur during the formation of spinel, which will deteriorate the compactness, strength and slag resistance of composite refractories.

In order to avoid low-density refractory materials, the spinel-containing refractory materials produced by the existing technology usually reduce the content of spinel, but the refractory materials prepared by this method have no advantages in refractoriness and thermal shock resistance