ENVIRONMENTAL ASPECTS OF CARBONATION LIME DISPOSAL

British Sugar factories temporarily store the carbonatation lime produ ced in the course of sugar manufacturing in lagoons before selling it to farmers during the summer. This procedure frequently causes odour e missions owing to the completely anaerobic degradation. The factors in volved, pH, temperature, and organic substance were investigated in th e laboratory and under operating conditions. Sulfides, indoles and thi oles were identified as the principal odour substances. Odours develop ed when the pH-value fell very rapidly to less than 9 and at a volatil e aliphatic acid content of about 20 g/kg. As high a pH value as possi ble in the first carbonatation is desirable. Temperatures of under 20- degrees-C in the carbonatation lime reduce odour development. To exclu de odour development, the organic substance content must amount to les s than 0.1% of the sugar in the lime. A controlled, odour-free storage of the lime is so far not possible. Experimental additions of lime mi lk and biocides in part yielded promising results.