Ore mining and steel metallurgy industry

KROOSH multi-frequency screening technology has proven itself in the mining and metallurgical
industry, primarily in such applications as:

Mining and processing of iron ore (both in the classification of crushed ore in wet grinding cycles in
concentrators, and in the final stage of sorting of rich iron ore in mining).
Uranium production
Gold mining (both in sorption tailings and grinding cycles)
Zinc production (obtaining zinc from zinc dust from electric arc furnaces)
Improving the quality of flux limestone in metallurgical production.

KROOSH technology solve the most difficult tasks that are almost impossible to solve with conventional vibrating screeners such as operating products with high moisture and / or sizing materials at the micron level.

Copper-zinc ore

One of the problems that arise in the processing of copper-zinc ores with tailings and various concentrates is that the loss of copper is approximately 10-15%, and loss of zinc is approximately 30-35%.

The main losses of copper and zinc occur in fine grain sizes and intergrowths of valuable minerals with each other and host rocks in large fractions.

Losses occur due to over-grinding of ore and excessive sludge of mineral particles due to the imperfection of classification processes in grinding cycles.

KROOSH technology allows:

improve the efficiency of ore screening;
increase the mass fraction of valuable metals and minerals;
to increase the extraction of fines into the undersize product while excluding the extraction of large size classes.

Gold

In gold mining there are two areas where KROOSH technology allows you to solve complex problems
that conventional screeners can do much worse or not at all:

1. Gold-bearing ore: control screening of the undersize product, due to which the gold production
increases.

2. Sorption tailings: re-cleaning of sorption tailings to recover additional gold.

Uranium

KROOSH screeners are used in challenging applications including wet processes.
For example, in the production of uranium (according to the technology of uranium mining by the in-situ
method), there was a need to filter the slurry (ion-exchange resin in a dilute solution of sulfuric acid)
with the simultaneous removal of small particles and foreign mechanical suspensions (clay and sand
particles) less than 0.3 mm.

The customer has encountered the following problems:

low productivity of a conventional (single-frequency) screener;
unsatisfactory filtration of the solution due to clogging of the mesh;
as a result, the loss of product due to the need to work with a larger aperture.

The conventional vibrating screener was replaced with a multi-frequency KROOSH vibrating screener,
resulting in the following measurements:

1. significantly increased the productivity of the production line,
2. the required quality and stable dehydration of the ion-exchange resin achieved,
3. clogging and sticking of the screen mesh is excluded.

Thus, our equipment allowed us to solve a complex, previously unsolvable problem.

Zinc

One of the difficult tasks that KROOSH screeners solve is working with zinc concentrate.

In particular, such a task is screening the slurry of basic non-ferrous metal sulfates in order to purify zinc sulfate from the gypsum component for efficient operation of the line.

Flux Limestone & Burnt Lime

Ferrous metal industry uses flux limestone and burnt lime, and high quality of smelting requires high quality of these products.

For example, one of the tasks is to improve the quality of raw materials for metallurgical processing by removing a fine fraction of 0-5 mm from the process with high level of product moisture up to 5%.

Sometimes the task is not so difficult in terms of technology, but its solution depends on other limitations. For example, when it’s necessary to place the screener on a small footprint as well as to ensure minimal vibration loads on building structures (for example, in the tower at +40 or +22 m high).

KROOSH equipment also solves this problem due to the high specific productivity on the one hand, and the almost absence of dynamic loads on the structure, on the other hand.

Copper-zinc ore

Purpose:

to separate ore 0-8mm after crushing so that this ore goes to mills for 0.075mm grinding, and as a result to increase efficiency of the whole line.

Application:

mining companies and processing plants of non-ferrous metallurgy.

KROOSH Results:

decreasing ore sizing helped to increased efficiency and quality of the grinding process at 0.075mm.

Reason of installation:

tests for new line

Product:

copper-zinc 0-8mm (moisture 10%) before primary milling.

Gold (adsorption tailings)

Purpose:

additional gold extraction from absorption tailings including from the fines coming from another vibratory screener. This is the task which is not possible for standard vibratory screeners. The task was to reclean 0.04mm carbon slime from adsorption tailings.

Application:

gold extraction plants.

KROOSH Results:

gold content in the good product reached 68 gram per metric ton what was not the case before.

Reason of installation:

the customer couldn’t receive on-spec good product with the conventional screeners.

Product:

gold-containing coal of size 0.1-0.4mm.

Uranium (by in-situ recovery method)

Purpose:

to improve the quality of the product by filtering the pulp (ion-exchange resin in a dilute solution of sulfuric acid) with the simultaneous removal of small particles and foreign mechanical suspensions (clay and sand particles) less than 0.3 mm in size (the technology of uranium mining by the in-situ recovery method).

Application:

uranium industry plants

KROOSH Results:

the productivity of the technological line has been significantly increased, the required quality and stable dehydration of the ion-exchange.

Reason of installation:

the customer couldn’t receive on-spec good product with the conventional screeners.

Product:

dewatered ion exchange resin of +0.3 mm particle size

Burnt lime (iron industry)

Purpose:

burnt lime screening with cut 10 мм and temperature up to 80°С.

Application:

raw material preparation in iron industry.

KROOSH Results:

the screener was installed on a very small footprint and this allowed to perform on-spec screening at high floor of metal tower +22.0 m.

Reason of installation:

not enough room to install a conventional vibrating screener as well as demand to low dynamic loads of the screener.

Product:

burnt lime 10-50 mm in feed.

Process wastes: e.g. Zinc concentrate

Purpose:

screening pulp of basic sulfates of non- ferrous metals in order to purify zinc sulfate from the gypsum component with a fineness of +0.04 mm.

Application:

mining and processing plants of non- ferrous metallurgy.

KROOSH Results:

the zinc content in the concentrate after removing the gypsum component from the original product reaches 45-47% against 25% in the original product, with the almost absence of gypsum in the zinc concentrate.

Reason of installation:

the customer couldn’t receive on-spec good product with the conventional screeners.

Product:

processed waste from electric steelmaking: separation of gypsum from zinc concentrate 0-0.04mm

Copper tailings

Purpose:

to remove ultrafine ores with low grades of metals, to return copper ore fine fractions from long-term accumulated tailings to industrial processing.

Application:

technogenic deposits (copper ore tailings).

KROOSH Results:

for the first time ever the customer could increase efficiency as follows - copper ore fine fractions from long-term accumulated tailings were successfully returned to industrial processing.

Reason of installation:

the customer couldn’t receive on-spec good product with the conventional screeners.

Product:

copper ore tailings - fine fractions <1 mm (0.3mm, 0.6mm…) with high copper content. The project was implemented together with company MetalQuim (Chile) for one of the famous copper producers in Chile.

Gold (gold concentrate)

Purpose:

to increase yield of gold production with the more efficient screening.

Application:

gold extracting factory.

KROOSH Results:

Highly efficient return to the cycle of ultrafine grinding of the fraction +0.045 mm with the content of undiscovered gold in the ore in the amount of 85-170 g/t, which previously went into irretrievable losses during further enrichment.

Reason of installation:

the customer couldn’t receive on-spec good product with the conventional screeners.

Product:

gold concentrate, size 0-0.045 мм.

Burnt lime (iron industry)

Purpose:

burnt lime screening with cut 10 мм and temperature up to 80°С.

Application:

raw material preparation in iron industry.

KROOSH Results:

the screener was installed on a very small footprint and this allowed to perform on-spec screening at high floor of metal tower +22.0 m.

Reason of installation:

not enough room to install a conventional vibrating screener as well as demand to low dynamic loads of the screener.

Product:

burnt lime 10-50 mm in feed.