Drying of sewage sludge eliminates mercury emission when the sludge is used in cement kilns as fuel. Removal of mercury from the anaerobically digested sludge is possible in the temperature range from 200 to 290 °C. Experiments showed that mercury concentrations in 4-mm-layer samples decrease from 2 mg.kg^-1 to below 0,5 mg.kg^-1 in 30 min. At temperatures below 150 °C, mercury concentrations in the studied samples did not appreciably change.