Suchergebnisse

The aim of the present work is to evaluate how the vegetable oil refining sludge produced by the agro-food industry could be composted using carbonatation lime and green waste as bulking agents. To achieve this goal, three windrows were prepared with different mixtures: windrow 1 contained oil sludge and green waste (20:10 on a wet mass basis) while windrow 2 contained oil sludge, green waste and carbonatation lime (20:10:10, on a wet mass basis). The composition of windrow 3 was: oil sludge, green waste and carbonatation lime (20:10:20, on a wet mass basis). The results showed that the use of carbonatation lime for composting vegetable oil refining sludge was able to regulate the high acidity of the sludge and thus to obtain an optimal pH value for the launching and maintenance of the composting process. The addition of carbonatation lime also gave better reduction of microbial activity without any negative effect on composting. The compost prepared with oil refining sludge (49% fresh mass), carbonatation lime (27%) and green waste (24%) exhibited the best quality with C/N ratio and pH values within the norm NFU44-051. These promising results could be a sustainable solution for the valorization of both oil refining sludge and sugar carbonatation lime.

Poultry manure is known as source of bacterial pathogens which decrease its direct application as fertilizer on agricultural land. The co-composting with carbonation lime of sugar factory was tested to valorize poultry manure. The evolution of physicochemical and microbiological parameters describing the composting of a mixture of poultry manure, municipal organic wastes and carbonation lime was monitored. The influence of carbonation lime addition on composting of poultry manure was determined. Three different mixtures were composted. The results showed the same evolution of the temperature and organic matter loss for all tests. The final products have C/N ratios (10.6–10.9) and pH values (7.3–7.8) within the standard. In addition, the monitoring of the microbial population (total coliforms, fecal coliforms and fecal streptococci) during the composting process showed that the produced composts are mature and hygienic. Based on the finding obtained, the addition of carbonation lime to poultry manure further improves its composting.