Compost produced from organic fraction of municipal solid waste, primary stabilized sewage sludge and natural zeolite.

The aim of this work is to present the physicochemical characteristics of the compost produced from dewatered anaerobically stabilized primary sewage sludge (DASPSS), organic fraction of municipal solid waste (OFMSW) and the metal uptaken by zeolite (clinoptilolite). The final results indicated that the composted material produced from clinoptilolite 20% w/w and 80% w/w DASPSS and OFMSW (60% and 40%, respectively) provided better soil conditioning compared to the compost produced from DASPSS. The co-composting products had a higher concentration of total humic and organic matter (O.M.) than the sewage sludge compost. Also, the heavy metals concentration in the final products was in lower concentration than in the sewage sludge compost. The zeolite appeared to uptake a significant (p<0.05) amount of metals. Specifically, the use of 20-25% w/w of clinoptilolite appears to uptake 100% of Cd, 10-15% of Cr, 28-45% of Cu, 41-47% of Fe, Mn 9-24% of Mn, 50-55% of Ni and Pb, and 40-46% of Zn. Although by the application of the composting process, the reduction in dry mass is between 30% and 40% for all samples.