VIABILITY ANALYSIS OF SOLID WASTE COMPOSTING FROM WASTEWATER TREATMENT PLANT IN FOOD INDUSTRY.

Abstract

With the objective to analyze the viability of composting organic waste and the excess sludge from food industry wastewater treatment plant (WTP), was built a pilot composting plant. This was fitted with waste generated in the company in the following composition: 5% by mass (7.5 kg) of refectory remains, 4% (6 kg) of WTP waste from the static screen, 60% (90 kg) of excess sludge from biological treatment also of the WTP, 1% (1.5 kg) of biomass boiler ash, and 30% (45 kg) of pruning and gardening as structuring agent. Over 90 days were monitored temperature, pH and moisture to ensure the correct procedure. After 32 days it was found that the composted material entered in maturation phase. Samples were sent for analysis in external laboratory to evaluate the presence of heavy metals, viable helminth eggs, salmonella, and thermotolerant coliforms resulting in the values within the allowed according to CONAMA resolution 375/2006 (Brazilian Standards). With the collected data it was found a high operational, financial and environmental viability to realize the internal composting process of excess sludge and solid waste, resulting in a soil corrective for the company existing eucalyptus reforestation and ensuring correct allocation of solid waste generated by industry, from the point of generation until its final destination, besides to aggregate value in which until now was assumed as waste.