Valorization of olive mill wastewaters by composting process in the germination of soybean

摘要

Growing quantities of vegetable water are dumped into nature every year without any control. By their chemical composition, they have a very high polluting power. In the context of research on treatment and recovery processes, we are interested in therecovery of these effluents by the humidification of composts in a context of soil improvement, but also by the treatment of electrocoagulation and their recovery in germination of Glycine soybeans max. Physico-chemical analysis of raw margin revealed that it was characterized by an acidic pH, black colour, and contained a high organic and mineral load that was not biodegradable. After treatment, these characteristics experienced very remarkable reductions in phenolic compounds (15.27), chemical oxygen demand (COD) of 98, biochemical oxygen demand during five days (BOD5) (86.5), conductivity (82), salinity (82.77) their pH increased until neutrality (7.62), and that the colour had been considerably reduced in intensity as a result of a reductionin their polluting load. The effects on the germination of soybean were favourable for all the dilutions used. During the maturation of composts precisely in the mesophilic phase, we observed degradations and transformations of organic matter and also significant transformation of the total mass of initial organic carbon. At the end of the maturation obtained after four months, the high germination indices obtained testify to good stability of the composts and a decrease in its phytotoxicity.