Origin of the project
In 2011, one of the main builders in Krasnoyarsk (Siberia) contacted BERALMAR’s representatives in Russia. As a builder, and due to its geographical location, its supply of building materials, particularly bricks, was a critical issue. So, considering its own annual consumption of solid bricks, manufacturing them itself was raised, anticipating that the majority of the proposed production (300 tonnes/day) would be for its own use. Their main worry was manufacturing costs and, with energy understood to be the main cost, they proposed the only fuel to be used in the plant to be local coal.
A peculiar fuel
The client had knocked on the right door, because BERALMAR is the sector leader in solid fuel technologies. The problem with local coal is that in Siberia, due to the permafrost (permanent ice in the subsoil), the coal comes out of the mine mixed with ice and it even remains in this state during distribution over a large part of the year. So the coal had to reach the future ceramics plant frozen or not, but in any case with a lot of moisture, of over 40%. To be able to use this coal it was necessary to install a special dryer, from where an interesting closed circuit for handling this fuel began: the wet coal passes through a rotary drum dryer that lowers its moisture level from approximately 40% to less than 10%. At the outlet from the coal dryer, a small portion of the coal is sent to a model CSD combustion chamber, which burns the coal to generate the heat the rotary drum dryer needs for its coal drying process. Meanwhile, the majority of the coal goes to the kiln combustion system, a PROMATIC model, which in turn includes a drying system (from <10% to <2% moisture) for the coal during the milling process.
Avoiding the use of auxiliary fuels
The kiln is therefore equipped with a PROMATIC system and is designed to carry out the firing process without the aid of any additional preheating fuel by extending the preheating zone and providing the kiln ventilation system with extra capacity to transfer the heat from the firing zone to the preheating zone at higher pressure.
On the other hand, a direct kiln car stacking dryer was selected for the brick drying process, with a single tunnel, LEVANTE model. This type of dryer is the most efficient (in spite of its other known advantages) and, combined with hard extrusion with a maximum of 16% moisture in the clay, the proposed dryer was capable of functioning exclusively with the hot air recovered from the kiln, despite the extreme winter temperatures.
This is how the KCM-2 ceramics plant in Krasnoyarsk was conceived and built, with outstanding operating data:
Production: 300 tonnes/day of solid Russian bricks (3.7 kg).
Total production workers: 24.
Total thermal consumption: 330 kcal/kg in firing and drying.
Fuel: 100% coal at 5,000 kcal/kg.