Composting of effluent from a new two-phases centrifuge olive mill. Microbial characterization of the compost

A study to evaluate the quality of cured compost obtained by a mixture of crude olive husks, oil mill wastewaters and fresh olive tree leaves inoculated with cow manure, after 6 months of composting, has been conducted. Biological activities (ATP, DHA, DNA contents and enzymatic activities), several microbiological groups (including pathogenic bacteria, E.coli and Salmonellae), microflora composition were determined. Phytotoxicity tests were also carried out. The composting process brought about the total disappearance of phytotoxicity encountered in raw materials. The development of enzymatic activities was positive and no pathogen was found. The compost can therefore be satisfactorily used as amendment for agricultural crops.