Phosphorus distribution in untreated and composted solid fractions from slurry separation.

摘要: The distribution of phosphorus (P) (water-soluble inorganic P [P i ], acid-soluble , and residual P) was determined in 40 samples solids from solid—liquid separated slurry. These were collected separation plants using different technologies, separating by simple mechanical means, flocculation as pre-treatment before or anaerobic digestion followed centrifugation. Simple yielded a low solid TP content (8—9 g kg -1 dry matter [DM]) compared with (26 DM) digestion-centrifugation (33.4 DM). Acid-soluble predominated the high P-yielding solids, whereas organic-bound minor component all slurry solids. significantly correlated total (TP) (R 2 = 0.855 R 0.584), but water-soluble uncorrelated 0.077). relative to showed proportion separation, absolute concentrations highest digestion-centrifugation. Three fractions, representing range variability produced techniques, composted for 30 d, after composting. Total mass conserved during composting, decreased most cases. pronounced decrease observed composting flocculation, However, changes short- medium-term bioavailability modest, thus potential benefits regarding storage handling can presumably be realized without seriously compromising fertilization quality.