Device and method for decomposing rare earth ore through sulfuric acid low-temperature dynamic roasting

Abstract

The invention discloses a device for decomposing rare earth ore through sulfuric acid low-temperature dynamic roasting, which comprises a sulfuric acid low-temperature dynamic roasting kiln, and a high voltage constant-current tail gas liquefying treatment system which is communicated with the sulfuric acid low-temperature dynamic roasting kiln and purifies flue gas output by the sulfuric acid low-temperature dynamic roasting kiln, wherein the sulfuric acid low-temperature dynamic roasting kiln comprises a raw material storage tank, a sulfuric acid storage tank, a double-screw continuous mixer, a kiln body, a material stirring system arranged at the bottom of the kiln body, and a combustion chamber arranged outside the kiln body; and the high voltage constant-current tail gas liquefying treatment system comprises a cooling tower, a high voltage constant-current tail gas liquefying tower, a high-efficiency cyclone separator, an exhaust fan, and a foam tower. The invention also discloses a method for decomposing rare earth ore through sulfuric acid low-temperature dynamic roasting by the device. The device and the method has wide adaptability for decomposing minerals and ensure that the decomposition rate is over 96 percent; and the device and the method can ensure that the materials are fully decomposed and the final tail gas meets the emission standard.

Description

technical field [0001] The invention belongs to the technical field of rare earth ore roasting and decomposition, and in particular relates to a device and method for sulfuric acid low-temperature dynamic roasting and decomposition of rare earth ore. Background technique [0002] China is a country rich in rare earth resources. Except for the southern ion-type mines that are leached by wet method, almost the remaining major minerals can be processed by sulfuric acid roasting. At present, the method commonly used in the decomposition of rare earth concentrates in China is the rotary kiln invented by Academician Zhang Guocheng. High-temperature sulfuric acid roasting method, this method has made great contributions to the treatment of Baotou rare earth concentrates in my country. However, with the development of the times and technology, the industry generally believes that this method still has the following disadvantages: (1) The problem of sticking to the kiln during the mat...

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Problems solved by technology

However, with the development of the times and technology, the industry generally believes that this method still has the following disadvantages: (1) The problem of sticking to the kiln during the material roasting process can only be solved by excessive sulfuric acid or external force cleaning, and the consumption of sulfuric acid is 1.2 to 1.5 theoretically. (2) In order to achieve the decomposition rate, a high temperature of 800°C to 1000°C must be used, which consumes a lot of energy, generally 300 to 500 kg of standard coal per ton of concentrate, and in some places it reaches more than 600 kg; (3) due to sulfuric acid Large consumption, high temperature, high content of sulfuric acid fumes in the tail gas, high temperature, and difficult treatment. Although some places meet environmental protection requirements, the investment in tail gas treatment equipment is high, and the environmental pollution problem is difficult to solve

The use of rotary kiln sulfuric acid high temperature treatment method has been difficult to meet the current status of energy saving and environmental pollution reduction

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