Devnya Tsiment AD

Barage Complect Ltd. has been operating since 1998. Up to the present moment Barage Complect Ltd. has executed on the grounds of Devnya Tsiment AD works in the field of design, construction and installation on the sites: “Mill for grinding and transportation of coal”, “Trestle to coal mill”, “Silo to coal dust feeding installation to furnaces No. 3 and 4”, “Substation and transformer station to furnaces No. 3 and 4”, “Supporting walls in a common warehouse”, “Supporting walls and hoppers for coal and petrocoke in a coal warehouse”.

“Construction and repair works in an administrative building of Devnya Tsiment AD“, “Pile foundations for silo for transportation of fly ash to furnaces No. 5 and 6”, “Building for air compressors to furnaces No. 5 and 6”, “MSS – control center to furnaces No. 5 and 6”, “Demolition of old coal facility, hoppers and trestle to it”, “Delivery and installation of metal hoppers for coal and petrocoke”, etc.

The chief designer of the project is LOESCHE Latinoamericana S.A. The subcontractors for the construction part are the Spanish companies TECHMINOR and BAKKEN S.A. The project is adapted to the Bulgarian design standards by Balkanstroy AD.

The project includes installation for transportation and storage of the dust, as well as the new combustion installation for furnaces No. 5 and 6.

Construction and installation works on the site include:

The foundation of the mill is designed as a surface footing from a minimum of 600 tons of concrete in order to absorb the vibrations and avoid the unwanted resonance effects.

The basis of the mill is an arch-shaped welded construction with main frame and anchor bolts, machined reducer, three supports with integrated bearing boxes linked through bridging components in order to withstand the secondary forces.

The mill building has an open design. It is built from a steel welded construction, the platforms and the stairs are of fluted sheet iron with a bearing force of 250 kg/m3, side support against the wind attached with clamps and a ladder from level +0.00 m to +33.60 m;

The supporting structure for the coal dust silo with a 500 m3 capacity is located on level +15.15 m. On level +21.90 a steel support structure connects the two coals and coke feeding hoppers with a capacity for 300 tons of unprocessed coal / coke.

The coal transportation trestle is a steel construction with a total length of 150 m on which the coal is transported. The coal is poured into a receiving hopper. The facility has two axes where the transportation is carried out – Conveyer 1 and Conveyer 2. The transition between the two conveyers is done at a transfer tower, which is a metal construction on three levels, coated with LT sheet iron.

Coal dust silo – furnaces No. 3 and 4

The chief designer of the project is Devnyainvest EOOD – HIMPROEKT, Varna. The project includes the redesign of a steel construction for a coal dust silo in accordance with the new requirements and the new technological assignments of the investor CTG Italcementi Group.

The construction and installation works include:

The steel construction is on five floor levels, with technological areas built on them. The entire housing of the construction is clad in LT sheet iron.

The main load bearing construction is composed of frames, clung to three supporting knots.

The internal housing is composed of two frame constructions with reinforcing K-links.The horizontal impulse earthquake forces are absorbed by framework steel constructions and reinforcing links between them.

Each working area is constructed as an installation scheme, composed of main load-bearing and secondary beams. The transition between the separate levels is done through a steel ladder cage, positioned on the outside of the main construction. The ladder cage is connected with the main housing through steel beams at elevation +8.25 m and +16.50 m. Metal pipe rails are constructed in order to guarantee the safety of level +16.50 m of the ladder cage.

The project includes construction of new supporting walls in the Gypsum Warehouse. The new supporting walls separate the existing areas in the Common Warehouse building and new warehouses for gypsum and additional materials are formed. The supporting walls are 9.0 m high with a maximum thickness of the foundation 0.90 m.

There are shafts constructed for receiving bulk material from dumper trucks in the ingoing area. The supporting wall in these areas has a crown height of 11.0 m and the maximum thickness of the foundation is 1.0 m.

The project includes the reconstruction of an existing gypsum hopper and existing hopper for additional materials and the construction of new parts for the hoppers. The reconstruction is done in relation to extensive repairs of mill “Г” from the Cement Workshop with the aim to improve the flow of the gypsum hopper and hopper for additional materials.

The reconstruction of the hoppers is done with partial usage of the constructions already at hand. The cladding of the gypsum hopper is constructed from scratch and is welded to the upper belt of the supporting beams. The walls of the additional materials hopper are partially preserved. In order to achieve better flow at the bottom part of the hoppers, the same have been coated with cold rolled sheet iron.

The project includes the construction of foundations for a load-bearing steel construction for a coal dust silo at furnaces No. 5 and 6 and of foundations for a one-storey, reinforced concrete building for air-compressors. The silo foundation is constructed as a pile foundation. The type of the piles used is driven reinforced concrete with dimensions 30/30 cm, 9 m in length – numbering 32 in total, in groups of 8 under each column.

The air compressor building is single storey. The construction is reinforced concrete, monolithic. The dimensions are 9 x 7 meters. The walls are of brick masonry. The roof slab is reinforced concrete.

The unit is being built within the existing Common Warehouse for Raw Materials. The project includes construction of new supporting walls and concrete hoppers for coal and petrocoke. Two steel hoppers for coal and petrocoke have also been installed which lie on reinforced concrete structures, specifically built for them in advance. The steel hoppers have an asymmetric shape, which shape mirrors the opposing one.

The walls are of smooth sheet iron with a thickness of 8 mm, which rests on horizontal ribs. At the top of the hoppers are shaped beams, which transmit the loads to the four corners of the hoppers through the horizontal belts. The step over the reinforced concrete structure is implemented through six anchor devices, set during the casting of the concrete.

The project includes extension of an existing line conveyer for transportation of coal and coke with a new line conveyor, starting from the new metal and concrete hoppers in the Coal Warehouse. The main changes are related to the construction of a new transition bridge, symmetrical to the first one, on the other side of the sloped section of the transportation line.

The project also entails change in the structure of the existing transfer tower due to replacement of the filter after the transition bridge between the new and the existing section of the line. In terms of structure, the site is divided into three parts: