SU730847A1 - Method of processing pyrrhotine ores and concentrates - Google Patents

Description

(54) METHOD FOR PROCESSING PYRROTINE ORES AND CONCENTRATES The invention relates to the field of non-ferrous metallurgy, in particular to acto-clave hydrometallurgy, and can be used in the processing of pyrrhotite ores and concentrates. A known method of processing pyrrhotite ores and concentrates, including act-clave leaching at elevated pressures of oxygen-containing oxidizing gas and temperature in a sulfuric acid medium to produce extra-alkaline pulp and recycling part of this pulp, as well as separating the oxide and sulphide phases of the spent pulp of the magnet separation of the pulp and magnet separation of the pulp and magnet separation of the pulp and magnet separation of the pulp and magnet separation of the pulp and magnet separation sulphide phase 1. The disadvantages of this method are the insufficient process intensity and the high rate of formation of wall accretions, which reduces the productivity st autoclave object of the invention - intensification process and speed reduction obrazo7 Vani accretions. The goal is achieved by leaching prior to decomposition of pyrrhotite by 90-100%, and the recycled part of the excreted pulp is 5-20% of the volume of the original pulp. The recycled part of the pulp is subjected to aging for 12-70 hours. The method is carried out as follows: An autoclave is charged with an aqueous pulp of pyrrhotite concentrate with a fraction content of 0.044 m 80-95% at t: W equal to 1-3 with the addition of 520 vol. taken immediately after leaching, an oxygen-containing oxidizing gas, such as air or air / enriched with oxygen under a pressure of 7-15 atm, is supplied to the autoclave. The process temperature is lOO-llO C. The stirring intensity, estimated by the sulfite number Kc, is contained within 1–4 d.c.pte. — Leaching leads to 90–100% decomposition of pyrrhotite, which is ensured by the selection of process parameters: oxygen pressure, temperature, intensity of mixing, leaching time, pH of leached pulp 1.5-2 / 0. The effectiveness of circulating pulp is newed if it is subjected to retention for 12-70 h. Example 1, A 3-liter autoclave is loaded with aqueous nickel pulp containing pyrrhotite concentrate with a fraction of 0.044 mm 90% with 5% of the pulp added the volume of the original pulp, the retention time (aging) of the circulating pulp is 12 hours. The concentrate contains 3.7% nickel, 1.9% copper, 48.0% iron and 29.0% sulfur. Mineralogically, it consists of 60% pyrrhotite and 10.7% Pentlandite, process temperature 108 ± 2 ° C, duration 4 hours. After leaching, serosulfide granules are aggregated at 130 ± 2 ° C for 0.5 hours in an oxygen atmosphere. The resulting pulp is passed through a sieve with a cell O, 1 mm, collected in the plus class serosulfide granules. The granule yield is calculated as the ratio of the weight of the granules to the weight of the initial concentrate. In the pulp after leaching, the fluidity (visually), the moisture content of the precipitates after filtration, and the degree of decomposition of pyrrhotite and pentlandite are determined. The results are shown in Table 1, here are the results of the blank experiment. Table

12

EXAMPLE 2 The process is carried out analogously to Example 1, only the quantity of circulating pulp is

20

12

Example 3, Testing was conducted in a semi-continuous installation in continuous mode. The installation consists of two series-connected autoclaves with a capacity of 1.74 m. The composition of the leachable concentrate .i.-leaching regime is similar to example 1. 10% vt% of leached pulp volume, initial, aging time 20 h, are used as recycling additive.

The control of the formation of solid geyelastic, gypsum and other formations (walls) is carried out by visual inspection of the heat exchangers after stopping the autoclaves.

Inspection of heat exchangers after ten days, continuous operation of the autocla92 at O47.0. Flowing from 40.025.0

84.0 21.0 Poor 55.0 16.0 Pouring

20 vol.% Of the original. The test results and the results of idle experience are shown in table 2.

Table 2

 56.0

38,031,0 21,0 freezing

Bad 55.0 16.0 Pouring

WWII shows the almost complete absence of scans. And in the idle experience, after three days of operation, the nastil thickness is 3 mm, which almost completely blocks the heat exchange, i.e. the installation must be stopped to remove wall accretions.

Example 4. The tests were carried out in the same installation and under the same conditions as in example 3.

In the experiment with the addition of circulating pulp, the amount of oxidized iron in the final sulphide concentrate is 6.8%, and in the blank - 18%, that is, three times and more.

Claims (2)

Iron in sulphide concentrate is an unnecessary impurity, since the main task of this technological scheme is to maximize the output of iron from the original concentrate. This is necessary because With further processing, the loss of non-ferrous metals with ferrous slags increases. The proposed method allows increasing the decomposition depth of sulphides, improving the performance of aytoklavov by reducing the time spent on removing walling, as well as improving the quality of the resulting sulphide concentrate. Claims 1. Method for processing pyrrhotite ores and concentrates vklyuchayupshy avtoKJiaBHoe vyschelatgivanie at elevated pressures and temperatures gazaokislitel oxygenate in sulfuric acid to yield leached slurry and recirculating a portion of the pulp, characterized in that, in order to intensify the process and reducing the formation of accretions speed , leaching is carried out until the decomposition of pyrrhotite is 90-100%, and the recycled part of the exfoliated pulp is 5-20% of the original pulp volume. 2. The method according to claim 1, about tl and h and tola, and so that the recycled part of the pulp is subjected to aging for 12-70 hours. Sources of information taken into account in the examination 1. P.G.Thornhlll Avtoclave treatment of pyrrholite for sulphur recovery. Goarn Canadian MetalT lurgical Qmarterly, 8, 2, 1969, p.219-225. ,