SU1668444A1 - Method for processing of scheelite concentrates - Google Patents

Abstract

The invention relates to the field of metallurgy of rare refractory metals and can be used for processing scheelite concentrates. The purpose of the invention is to simplify the process and reduce the consumption of reagents while maintaining the degree of extraction of tungsten and obtaining a tungsten trioxide-conditioned product. A portion of scheelite concentrate with a tungsten trioxide content of 57.8% was mixed by grinding with quartz sand. The amount of silica sand was taken from the calculation of the binding of scheelite calcium to calcium orthosilicate. The mixture in a thin layer of 2 to 5 mm was poured into a boat, which was loaded into the reactor and heated in a furnace to 1150 ° C when the steam-air mixture with a concentration of water vapor of 25 to 30% was fed into the reactor. The resulting gas phase was captured, condensed at 600 ° C to produce tungsten trioxide. The degree of extraction of tungsten trioxide was 98.8%

the content in the resulting product of tungsten trioxide 99,93%. 1 tab.

Description

The invention relates to the metallurgy of rare refractory metals, in particular to methods for processing scheelite concentrates.

The purpose of the invention is to simplify the process and reduce the consumption of reagents while maintaining the degree of tungsten recovery and obtaining a tungsten trioxide-conditioned product.

The method is carried out as follows.

Scheelite is mixed with SI02 in the calculation of calcium binding to calcium orthosilicate (Ca2S () and then calcined at a temperature of 1100-1350 ° C in a vapor-air mixture stream with conversion of tungsten trioxide to the gas phase with subsequent condensation of tungsten trioxide from the gas phase at 450-700 ° C.

The addition of silica sand is necessary to bind calcium into calcium orthosilicate.

When the vapor-air mixture interacts with the mixture consisting of scheelite concentrate and quartz fishing line, the following main reaction takes place at a temperature of 1100 ° C and higher:

2CaW04 + Si02 + 2nH20 Ca2SiO i +

+ 2W03

pN2OG

Example: A sample of scheelite concentrate (100 g) with a tungsten trioxide content of 57.8% was taken and mixed with quartz sand (based on calcium binding to calcium orthosilicate by co-grinding in an agate mortar). The resulting mixture was covered with a thin layer (2-5 mm) and covered with in the boat, the last was loaded into the reactor,

(L

WITH

Os О 00 4 4 Ј

in the oven. The temperature was raised to 1150 ° С and a vapor – air mixture with a water vapor concentration of 25–30%, preheated to the same temperature, was started to be fed into the reactor. At the exit of the reactor, a tungsten trioxide condensation system was mounted, the temperature in which was maintained at 600 ° C. From the reactor, a vapor-air mixture with tungsten trioxide entered the condensation system, where trioxide precipitated. Then, the vapor – gas mixture with impurities of volatile compounds of arsenic, phosphorus, sulfur, etc. entered into the form of cooled drexels filled with a sparing solution of alkali. The degree of tungsten was judged by the amount of residue by minus losses; determined by analysis of the solution in drexel s. The tungsten trioxide recovery rate was 98.8%. Chemical analysis of the obtained powder showed that the content of tungsten trioxide on it corresponds to 99.93%.

The results of subsequent experiments are given in the table.

Using the method will significantly improve the processing technology.

scheelite concentrates and reduce reagent consumption by eliminating reagent-intensive operations used in a known method for cleaning tungsten solutions and isolating ammonium para-tungstate.

Claims (1)

Invention Formula A method of processing scheelite concentrates, which includes mixing the concentrate with an inorganic reagent to produce a mixture, calcining the mixture in a vapor-air mixture, and then isolating tungsten trioxide, characterized by that. that, in order to simplify the process and reduce the consumption of reagents while maintaining the degree of tungsten recovery and obtaining the tungsten carbon dioxide product, mixing is carried out using quartz sand as the inorganic reagent in stoichiometric amounts necessary to bind the calcium scheelite to calcium ortho silicate , the calcination of the mixture is carried out at 1100-1350 ° C to obtain a gas phase containing tungsten, and the release of tungsten trioxide is carried out by condensing it from the gas phase at 450-700 ° C.