Employer: Ellatzite-Med AD
Designer: Geoproject EOOD
Contractors: Geotechmin OOD and Geostroy AD
Project implementation period: 2006 – 2008 

The implementation of the project “New Primary Crushing Unit KET-3” has optimised ore mining processes in Ellatzite mine by considerably shortening transport distances.

KET-3 was built in the inner contour of the mine at an elevation of 1,060 m under conditions of uninterrupted ore mining operations. It consists of a main building, a trestle, a transfer house and a rubber belt conveyor installed in a tunnel which was constructed together with KET-3.

The main building of KET-3 has a monolithic frame structure with multiple openings and storeys, supported by wall-washers, beams and columns to absorb horizontal forces and vertical impacts. The inter-storey height varies from 4 m to 12 m. The building has a total built-up area of 820 m2 and is 45 m high. It is equipped with two crushers “Allis” and “Krupp”, a 100-ton lifting capacity crane, a ventilation system, a power substation, a passenger lift, service and utility rooms.

The trestle has a reinforced concrete structure with an inclined slab which connects the main building with the transfer house. Two ore-conveying belts running from the crushers are installed inside the trestle. The transfer house is used to transfer ore from the trestle conveyor onto the tunnel conveyor. It is a reinforced concrete building made of solid beams with dimensions L 12 m, W 1 m, H 2.5 m. Its built-up area is 300 m2.

Geostroy AD provided special heavy lifting equipment for the construction of KET-3, including two tower-cranes Potain IGO 32 and МС 85В.

A transport tunnel was built in Ellatzite mining complex to convey the extracted ore between primary crushing units KET-2 and KET-3. The facility has a total length of 730 m and an effective cross section of 10.6 m2. A rubber-belt conveyor was installed inside the tunnel to facilitate ore transportation.

180 m of the tunnel were driven through compound technogenic embankment by applying the Symmetrix Method. This method was applied to 30 drillholes with 89 mm diameter on the circumference of the adit. The drillholes were injected with cement mortar for strengthening the massif.