Environmental agricultural protection is a concern due to the increase and poor exploitation of poultry manure. Two processes: (1) Thermal treatment and (2) quick wash were investigated to conserve the organic and mineral nutrients. The thermal treatment consists to minimize the weight and reduce the cost of preservation. The chemical treatment consists of a selective dissolution of phosphorus (P) with the most efficient acid from dried and wet poultry manure. Laboratory-scale trials have confirmed that the drying process is useful for reducing 85% total mass and has a disadvantage such as losing 38% nitrogen to air and 36% orthophosphorus in the liquid fraction which is a responsibility to runoff in water. The comparison between the inorganic acid (sulfuric, perchloric and Hydrochloric acid) and the organic acid (acetic acid) was carried out to dissolve more than 90% of P at pH 4.5 with all acids. The performance of sulfuric acid was confirmed; a small amount was consumed and the acid less expensive than the other acid. The centrifugation technique was tested by the reduction of 44% sulfuric acid with the same P extraction performance. As a result of P fresh manure extraction technique, two by-product are produced as organic fertilizer "solid washed" and inorganic fertilizer "struvite".
S. Abouda, N. Turki, M. Kasmi, I. Trabelsi, M. Ben Amor, A.H. Hamzaoui
Poultry manure, Organic fertilizer, Phosphorus, Acids, Struvite