Water-vapor gasification separation apparatus and method for waste printed circuit boards

Abstract

The invention provides a water-vapor gasification separation apparatus and a method for waste printed circuit boards. The method comprises the following steps: (1) adding a molten salt into a reaction furnace, pouring waste printed circuit boards into the reaction furnace under a normal pressure in an oxygen-free atmosphere, and controlling the reaction temperature to be 600-700 DEG C, so as to rapidly pyrolyze organics on circuit boards in the molten salt bath and generates products of an organic gas, coke and tar; and (2) performing water gas reaction on coke generated through pyrolysis and water vapor, so as to generate hydrogen and carbon dioxide. Metals in the circuit boards can be effectively separated and recovered after organics in the waste circuit boards are pyrolyzed and gasified. Hydrogen and the organic gas generated in the pyrolysis gasification separation process of the waste circuit boards in the salt bath can be used as fuels, and toxic halides contained in the waste circuit boards are absorbed by the molten salt and is converted into stable inorganic salts.

Description

technical field [0001] The invention relates to the technical field of solid waste resource recovery, in particular to a device and method for steam gasification and separation of waste printed circuit boards. Background technique [0002] For the recycling of e-waste, the most important process is to separate and classify the metals and plastics, and then carry out recycling by category. For large-scale electronic waste, such as refrigerators, TVs, washing machines, etc., it is easier to manually separate the shell for classification and recycling, while for small electronic waste or electronic parts, such as printed circuit boards, MP3, mobile phones, etc. It is difficult to further separate and classify metals and plastics. For small waste such as printed circuit boards, traditional methods for separating metals and plastics include thermal decomposition separation, dissolution separation, and mechanical crushing separation. Among these methods, the thermal decompositio...

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Problems solved by technology

Among these methods, the thermal decomposition separation method is to burn or thermally decompose the plastic in the waste circuit board, because the organic halides such as bromine and chlorine contained in the plastic are catalyzed by metal copper, which can easily lead to a large amount of toxic gas dioxins. The generation of waste water brings great pollution to the air environment; the dissolution separation method uses strong acid to dissolve and extract the useful metals, and the waste liquid generated is expensive to deal with, and improper disposal often causes greater secondary pollution to the environment; the mechanical crushing and separation method requires Crushing the waste printed circuit boards into very small particles can be effectively separated, which requires a lot of power consumption, and it is difficult to completely separate metals from non-metals. In addition, the separated plastics are complex in composition and contain bromine and chlorine. Such as organic halides, it is difficult to directly reuse them as fuels or as chemical raw materials

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