Integrated device for sedimentation and dust collection and method for treating rhenium-containing dust with the device

Abstract

The invention relates to the technical field of gas dust removal equipment, in particular to an integrated device for sedimentation and dust collection and a method for treating rhenium-containing smoke with the device. The device is equipped with a sedimentation dust collection system. The sedimentation dust collection system is arranged side by side with a sedimentation area (14) and a drainage dust collection area (16). The drainage dust collection area (16) is provided with a drainage room (24) and a dust collection room (26) ), the dust collection chamber (26) is provided with a ceramic filter element filter tube (262); the drainage chamber (24) communicates with the settling area (14) through the air induction channel (32), and the bottom of the drainage chamber (24) passes through the drainage fan (241 ), the drainage pipe (242) communicates with the upper part of the dust collection hopper (263) at the bottom of the dust collection chamber (26). The dust collection integrated device is used to treat the rhenium-containing fume in the rhenium recovery process. Through the steps of sedimentation, drainage and dust collection, the efficient separation and retention of the dust in the rhenium-containing fume can be realized. It works at a temperature above 400°C. High-efficiency dust removal of rhenium-containing fumes can be realized, and the recovery rate of rhenium in the dust removal process is also guaranteed.

Description

technical field [0001] The invention relates to the technical field of gas dedusting equipment, in particular to an integrated device for sedimentation and dust collection, and a method for using the device to treat rhenium-containing smoke and dust in a rhenium recovery process. Background technique [0002] In the rhenium recovery process, when the rhenium is extracted and recovered from the rhenium-containing ore by using the traditional oxidation roasting method, the rhenium-containing ore is first roasted under aerobic conditions, and the rhenium sulfide (including Re 2 S 7 and ReS 2 ) is oxidized to high-valent rhenium oxide Re 2 o 7 . Re 2 o 7 Its boiling point is 361°C, with low boiling point and strong volatility. It volatilizes into the flue gas at the roasting temperature, and the extraction reaction is (Zhang Qixiu, edited by Zhao Qinsheng, "Tungsten and Molybdenum Metallurgy", September 2005, p. 212): 2Re 2 S 7 +21O 2 =2Re 2 o 7 + 14SO 2 , 4ReS 2 +...

AI Technical Summary

Problems solved by technology

[0004] To collect dust from rhenium-containing dust, Soviet researchers (rare metal metallurgy, written by A. H. Zelekman, translated by Song Chenguang, September 1982, pages 328-329) used dust collection chambers, cyclone dust collectors and electric The dust collection system composed of dust collectors is used to recover the dust. About 95% of the dust is recovered by the cyclone dust collector, and the remaining dust is recovered by the electric dust collector for the second time. The content of rhenium in the dust of the electric dust collector is 0.1-1.5%. In this dust collection system, a cyclone dust collector is installed behind the dust collection room. Since the cyclone dust collector uses centrifugal force to collect dust, it has direct requirements on the airflow velocity at the entrance, which limits the residence time of the dust in the dust collection room. In the case of a huge amount of rhenium-containing dust, the dust collection efficiency of the dust collection system can only reach 50-80%. Moreover, because the pressure drop and temperature drop of the cyclone dust collection are very fast, the dust collection system does not take insulation measures , a part of the rhenium oxide is agglomerated and mixed into the dust, resulting in a decrease in the recovery rate of rhenium;

[0005] Herman Starkey Corporation (Nonferrous Metal Extraction Metallurgy Handbook - Rare High Melting Point Metals (W, Mo, Re, Ti), 1999, pp. 392-394) In the semi-industrial test device for processing molybdenum roasting flue gas to recover rhenium, roasting After the dust is first collected by the gravity dust collection room, it enters the electric dust collection room for secondary dust collection. Two-stage Venturi tubes are used to collect fine particles and absorb rhenium; After sedimentation and dust collection, it directly enters the electric dust collection room. Since the gravity dust collector uses gravity to settle and separate the dust, it has a good interception effect on the dust particles larger than 50 μm, and the dust particles smaller than 50 μm enter the electric dust collection room. The electric dust collection room belongs to the fine dust collection, which mainly solves the small scattered dust, resulting in a very low overall dust collection efficiency, and can only be equipped with two-stage Venturi tubes for wet dust collection to ensure the overall efficiency of dust collection; the wet collection Dust not only produces wet dust that is difficult to dry, but also the rhenium element in it is difficult to recycle, which affects the overall recovery rate of rhenium;

[0006] Hunan Changzhong Machinery Co., Ltd. (201310565217.2) discloses a high-efficiency coal-fired PM2.5 filter and dust removal method, which consists of a three-stage filter system consisting of a gravity dust removal device, a cyclone dust removal device and a porous ceramic dust removal device. The dusty gas first passes through the gravity dust removal device The dust particles larger than 50 μm in the dust-containing gas naturally settle under the action of gravity, and then the coarsely filtered gas passes through the cyclone dust removal device, and the dust particles larger than 5 μm in the dust-containing gas are separated from the air flow under the centrifugal force of the rotating air flow , and finally through the porous ceramic dedusting device, the dust particles larger than 0.2 μm in the dusty gas are separated by the filter membrane of the porous ceramic dedusting device to form clean gas, which is discharged from the chimney through the induced draft fan; but this method is not suitable for the treatment of rhenium-containing soot. Due to the huge amount of rhenium-containing smoke and dust, the flow rate of the smoke flowing out from the outlet of the cyclone dust collector is very fast, which makes the porous ceramic dust collector have a large pressure load and the system is difficult to operate normally.

Images