Detrimental effects of olive mill wastewater on the composting process of agricultural wastes.
In order to study the suitability of composting olive mill wastewater (OMW-L) by repeated applications, OMW-L was added to one mixture of lawn trimmings and olive husks as bulking agents. The composting process of this mixture was compared with another pile having 35% of olive mill wastewater sludge (OMW-S) obtained from evaporation ponds and a third, as a control, without olive mill wastewater. The repeated applications of OMW-L resulted in a sharp decrease in respiration measurements after the first 20 days of composting and showed a re-increase after 40 days following the substituting of OMW-L by water. The OMW-L addition increased the rate of water-soluble phenols in the compost and caused the appearance of a phenol fraction of high molecular-mass (510 kDa) at the end of composting. OMW-L addition also caused a clear decrease in both thermophilic bacteria and thermophilic eumycete counts. A longer persistence of phytotoxicity was observed in comparison with the other piles. However, the OMW-S produced a compost with a high degree of maturity.
Abid
Nozha
N
Laboratoire des Bioprocédés, Centre de Biotechnologie de Sfax, Sfax, Tunisia.
Sayadi
Sami
S
D001419:Bacteria / Q000187:drug effects / Q000378:metabolism*; D002849:Chromatography, Gas; D004553:Electric Conductivity; D018525:Germination / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D031220:Lepidium sativum / Q000187:drug effects / Q000254:growth & development; D031658:Olea / Q000737:chemistry* / Q000633:toxicity; D010636:Phenols / Q000032:analysis; D006109:Poaceae / Q000737:chemistry; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology; D013234:Stem Cells; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D010636:Phenols; D012987:Soil; D014874:Water Pollutants, Chemical