| 摘要 |
<p>1. Improved process for obtaining a compost from organic waste products, in which the waste products are subjected to an aerobic fermentation after having, where appropriate, modified the composition by prior additions of carbon-containing, nitrogen-containing and/or phosphorus-containing materials, the said process being characterised in that it comprises the following steps ; a) Preparation of the waste products to be treated, involving : (I) an adjustment of the C/N ratio to between 20 and 30, (II) an adjustment of the pH to between 6.8 and 7.5, preferably between 7 and 7.5, (III) a homogenisation of the mass of waste products resulting in a homogeneous mass which easily allows air to pass and (IV) an adjustment of the moisture content to between 45 and 55% by weight, preferably between 50 and 55%, b) fermentation of the said mass under static aerobic conditions, in a zone where the mass of waste products is at rest and where its moisture content is maintained at between 45 and 55% by weight, advantageously between 50 and 55% by weight, with alternate circulation of air forced upward through the mass and downward through it, so as to maintain, within the mass, conditions suitable for ensuring the mesophilic growth of the bacteria, implying fermentation temperatures of 50 to 60 degrees C, preferably between 50 and 55 degrees C, c) supplementary fermentation, of shortened duration, while continuing the alternate circulation of air, but maintaining, within the mass, conditions suitable for ensuring the thermophilic growth of bacteria and the hygienisation of the waste products being treated, which implies temperatures above 70 degrees C, the duration of steps b) and c) above being such that virtually all the oxygen demands of the microorganisms present in the mass are satisfied, and d) maturing of the mass of residues, the mass being left at rest under static conditions, without air circulation.</p> |
