Comprehensive refurbishment of a multichamber shaft kiln

The multichamber shaft kiln at Leube Kalkwerk limeworks in Golling/Austria, is an extremely hard worker: Since its installation in 1989, it has been producing 200 t of burnt lime – that’s eight fully loaded trucks – every day. To keep that possible, extensive preventive and corrective maintenance measures are required every four or five years. This time around, on 27.03.2017, Leube shut down the kiln for a major repair job lasting six weeks. “The agenda included repairing the kiln’s inner lining and overhauling six firing chambers”, explains Michael Langegger, Head of Production and Maintenance. All electric drives and measuring instruments were serviced, as were all mechanical parts subject to wear and tear, including, for example, the conveying system and the exhaust flue.

Approximately 8000 hours of work

The lime plant’s own maintenance team attended to much of the work themselves. They invested 830 hours of work in mechanical repairs and another 470 hours in electric maintenance. Add to that the work performed by outside contractors: it took some 4000 hours just to repair the refractory lining of the multichamber shaft kiln. All in all, the refurbishment lasted from March to May 2017 and cost nearly a million Euros.

The multichamber shaft kiln produces burnt lime by firing 50 to 120 mm lumps of limestone at a temperature of approx. 1200° C. The limestone spends between 36 and 48 hours in the kiln, depending on the desired product quality. The kiln is fuelled with natural gas and pulverized lignite.