Process for regenerating carbon-containing adsorbents (adsorption agents)

摘要

Brown coal coke used as adsorbent is regenerated in a moving bed by washing (scrubbing) for adsorptive removal of sulphur dioxide and catalytic reduction of nitrogen oxides to nitrogen. The regeneration is carried out by washing sulphuric acid and soluble sulphates out of the brown coal coke with water at atmospheric pressure in a temperature range of 20-95 DEG C. The washing out can also be carried out under increased (superatmospheric) pressure at 5 bar and at an elevated temperature of 150 DEG C. Another method of regeneration comprises first driving out the sulphuric acid with superheated steam and subsequently washing out the soluble sulphates with water in the temperature range of 20-95 DEG C. The treatment of the brown coal coke in a container is carried out continuously or batchwise (discontinuously), with the brown coal coke being treated in countercurrent or cocurrent mode with the steam or water. The untreated waste water (effluent) from the regeneration is used for wetting of ash which is produced in the combustion process from which the flue gas arises. In addition, the waste water obtained can again be supplied to the washer after removal of the sulphuric acid.