Method for treating hazardous wastes through cooperation of metallurgical furnace

Abstract

The invention discloses a method for treating hazardous wastes through the cooperation of a metallurgical furnace. The method comprises the steps of sintering for agglomerating the hazardous wastes containing heavy metal, or condensing for agglomeratingthe hazardous wastes containing the heavy metal, and smelting the combustible hazardous wastes to form a finished product block so as to obtain analloy crude product containing the heavy metal. According to the method for treating the hazardous wastes through the cooperation of the metallurgical furnace provided by the invention, the hazardouswastes containing the heavy metal are treated through a melting furnace, valuable metal in the hazardous wastes containing the heavy metal is recycled, meanwhile, organic matters inthe combustible hazardous wastes are decomposed by high temperature of the melting furnace, and heat values in the organic matters are utilized, so that inthe smelting process of the hazardous wastes containing the heavy metal, the harmful element of the combustible hazardous wastes, and fly ash used as a first slag former or furnace slags produced by residue incineration is reduced to be below 0.1 percent, the wastes can be directly used as building materials and used for preparing rock wool and the like, and the metal recovery rate reaches to more than 90 percent.

Description

technical field [0001] The invention relates to a treatment and disposal technology for solid waste, especially hazardous waste, that is, a method for co-processing hazardous waste with metallurgical furnaces, which realizes the reduction and recycling of heavy metal-containing hazardous waste and combustible hazardous waste , belonging to the field of environmental technology. Background technique [0002] Statistics show that in 2016, my country's industrial hazardous waste production reached 47.8 million tons, a year-on-year growth rate of 18%. It is estimated that my country will maintain a compound growth rate of 15% in the next five years, which will increase from 42.2 million tons in 2015 to 84.88 million tons in 2020. According to the calculation of the average disposal price of hazardous waste at 2,200 yuan / ton, the market space for hazardous waste treatment in 2017 Exceeding the scale of 100 billion yuan, it will reach an output value of 186.7 billion yuan in 2020,...

AI Technical Summary

Problems solved by technology

[0003] If hazardous waste is not properly disposed of, it will cause great harm: 1) Destroy the ecological environment

Hazardous waste discharged and stored at will will pollute water and soil under the long-term infiltration and diffusion of rainwater and groundwater, and reduce the environmental function level of the area; 2) affect human health

Hazardous wastes cause poisoning through ingestion, inhalation, skin absorption, and eye contact, or cause dangerous events such as combustion and explosion; long-term hazards include long-term poisoning, carcinogenicity, teratogenicity, and mutagenesis caused by repeated exposure; sustainable development

Pollution of air, water, and soil caused by non-treatment or non-standard disposal of hazardous waste will also become a bottleneck restricting economic activities

[0004] At present, the treatment technologies of hazardous waste at home and abroad are mainly incineration and landfill. Recently, there are cement kiln co-processing sludge and fly ash in China. The operation cost is low, but the equipment needs to use cement kiln, and the disposal quantity and area are limited.

Generally speaking, there are some problems in domestic hazardous waste treatment at present: 1) Landfill method: Hazardous waste containing heavy metals is usually treated by this method. However, the leachate containing a variety of harmful substances has great hidden dangers to the surrounding groundwater and is prone to secondary pollution; secondly, the landfill occupies a large amount of land; thirdly, the construction requirements for a safe landfill are very strict. And it is required to maintain and manage at least 20 years after the closure of the site, so the construction and operation costs of the safe landfill are very expensive, and the purpose of capacity reduction and resource utilization cannot be achieved at the same time

2) Incineration method: Combustible solid and liquid hazardous waste is usually treated by incineration method. The incineration of hazardous waste will produce a large amount of acid gas and incompletely burned organic components and slag. If it is directly discharged into the environment, it will inevitably lead to Secondary pollution; the incineration method has high investment and operation management costs. In order to reduce secondary pollution, the incineration process must be equipped with pollution control facilities and complex testing instruments, which further increases the treatment cost.

The depletion furnace is picky about raw materials, and cannot contain chromium, lead, and zinc sludge, which limits the types of hazardous waste it can handle

Shenwu Group adopts the rotary hearth furnace process to recycle red nickel ore waste slag and iron in red mud, and has achieved good economic benefits, but it is almost impossible to recover chromium in waste slag

On the whole, at present, there is no technology with strong applicability and high recovery rate for the treatment of hazardous waste containing heavy metals in China, and there is no method to combine the treatment of hazardous waste containing heavy metals with the treatment of combustible hazardous waste

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