Menetelmä jätelipeän talteenottokattilan lentotuhkan käsittelemiseksi

摘要

The present invention relates to a method for the treatment of fly ash, which occurs in the combustion of spent liquor. The sodium sulphate in the fly ash is reduced to sodium sulphide by mixing the ash with charcoal and carrying out the reduction in a loaded condition. The temperature is preferably between 690 and 740 degrees C. The sodium sulphide obtained in this way is used in the preparation of digestion liquor with a sulphide content. Treating the sodium sulphate ash outside the recovery boiler, improves the boiler economy and reduced corrosion. <IMAGE>