A method for recovering waste heat from molten slag

Abstract

The invention discloses a method for recovering waste heat of melting slag. The method comprises the following steps of injecting high-temperature melting slag into a heat recovery pool, mixing the melting slag with molten metal with low melting point in the heat recovery pool while quickly cooling the melting slag into solid furnace slag, wherein the melting slag and the molten metal with the low melting point are subject to quick heat transfer, besides, the solid furnace slag floats to form a scum layer, and scums are discontinuously or continuously discharged; absorbing the heat of the molten metal with the low melting point by a vaporization cooling device arranged in the heat recovery pool to vaporize liquid in a sealing pipeline of the vaporization cooling device; preserving the formed steam for recycling. According to the method for recovering the waste heat of the melting slag, provided by the invention, the problems of high power consumption, high heat recovery difficulty, low heat recovery efficiency, difficult utilization of the melting slag after heat recovery and the like existing in an air quenching method and a revolving cup method are solved.

Description

technical field [0001] The invention relates to the technical field of waste heat recovery, in particular to a method for recovering waste heat from molten slag. Background technique [0002] Metallurgical molten slag is a by-product of pyrometallurgical production. The temperature is generally between 1200°C and 1600°C. The physical heat contained in the slag is very considerable, and the value of recycling is huge. Taking a blast furnace with an annual output of 100wt as an example, the amount of slag produced per ton of iron is ~300kg, the temperature of blast furnace slag is ~1450°C, and the sensible heat of ton of slag is equivalent to 59kg of standard coal, so the sensible heat contained in the annual output of blast furnace slag is equivalent to 1.77wt of standard coal; When smelting low-grade nickel ore (Ni2%~5%, Fe10%~15%) to produce nickel-iron alloy, the molten slag produced with the production of 1t of nickel-iron alloy at a temperature of 1500℃~1600℃ is as high ...

AI Technical Summary

Problems solved by technology

[0009] The main purpose of the present invention is to provide a method for recovering the waste heat of molten slag, aiming at recovering the waste heat of molten slag, innovatively using liquid low melting point metal as the medium to recover the waste heat of molten slag, fundamentally overcoming the wind quenching method and the rotary cup The power consumption of the method is large, the heat recovery is difficult, and the heat recovery efficiency is low.

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