Method and system for treating solid waste through smelting reduction process

Abstract

The invention provides a method and system for treating solid waste through a smelting reduction process. The method comprises the following steps of mixing and batching iron-containing solid waste to prepare an iron-containing material; preheating and pre-oxidizing the iron-containing material; spraying the preheated and pre-oxidized iron-containing material into an oxidation-reduction furnace by taking compressed air as carrier gas; spraying carbon-containing solid waste into the oxidation-reduction furnace by taking recycled coal gas as carrier gas, and reacting the carbon-containing solid waste with the iron-containing material to generate molten iron, carbon monoxide and furnace slag; and spraying high-temperature oxygen into the oxidation-reduction furnace, carrying out a secondary combustion reaction on the high-temperature oxygen and combustible components in ascending gas flow, and recycling coal gas generated by the secondary combustion reaction and coal gas which does not participate in the secondary combustion reaction. According to the method, traditional fuel, lime, dolomite and other fluxing agents do not need to be added, compressed air and recycled coal gas are adopted as carrier gas to convey materials, high-temperature oxygen is adopted as a combustion improver, and solid waste recycling and large-scale comprehensive utilization are achieved.

Description

technical field [0001] The invention relates to the technical field of industrial waste treatment, in particular to a method and system for treating solid waste by using a smelting reduction process. Background technique [0002] With the development of industrial production, the pressure on the environment and resources is also increasing. The discharge of industrial waste has affected and restricted the high-quality development of the industrial economy. Therefore, it is necessary to improve the comprehensive utilization level of industrial waste and improve the utilization efficiency. Industrial waste can be divided into solid waste, waste gas and wastewater. At present, most solid wastes are treated by passive stacking, which has not been fully utilized comprehensively, occupying a large amount of space, and harmful components will penetrate into the soil, causing serious harm to the soil and soil system. Cause serious dust pollution and heavy metal pollution. [0003]...

AI Technical Summary

Problems solved by technology

First of all, it has a great impact on the production technical indicators of sintered pellets. At the same time, it will lead to the circulation and enrichment of harmful elements in the blast furnace, accelerate the erosion of the lining, shorten the life of the blast furnace, cause waste of recyclable resources, and low resource utilization efficiency

However, the Weiss furnace method and the rotary kiln method are used to treat industrial solid waste, but there are generally problems of high fuel consumption, low recovery rate, high cost, and decentralized utilization.

[0004] The existing solid waste treatment methods require the addition of coal, lime, dolomite and other non-renewable resources, which cannot realize the large-scale comprehensive and coordinated utilization of solid waste; use oxygen-enriched hot air and nitrogen as carrier gas for injection, Cause high fuel consumption, low energy utilization rate, and high production cost; nitrogen oxides and other substances will be produced in the process of solid waste treatment, which is likely to cause secondary pollution problems

In addition, the particle size of solid waste is uneven, and the use of mixed injection will easily affect the stability of the injection system, and it is difficult to recycle ultrafine powder

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