Mariam Kasmi

Eco-friendly process combining physical–chemical and biological technics for the fermented dairy products waste pretreatment and reuse

Residual fermented dairy products resulting from process defects or from expired shelf life products are considered as waste. Thus, dairies wastewater treatment plants (WWTP) suffer high input effluents polluting load. In this study, fermented residuals separation from the plant wastewater is proposed. In the aim to meet the municipal WWTP input limits, a pretreatment combining physical-chemical and biological processes was investigated to reduce residual fermented dairy products polluting effect. Yoghurt (Y) and fermented milk products (RL) were considered. Raw samples chemical oxygen demand (COD) values were assessed at 152 and 246 g.L-1 for Y and RL products, respectively. Following the thermal coagulation, maximum removal rates were recorded at 80 °C. Resulting whey stabilization contributed to the removal rates enhance to reach 72% and 87% for Y and RL samples; respectively. Residual whey sugar content was fermented using Candida strains. Bacterial growth and strains degrading potential were discussed. C. krusei strain achieved the most important removal rates of 78% and 85% with Y and RL medium, respectively. Global COD removal rates exceeded 93%.

Organic Compounds and Heavy Metals Simultaneous Removal from a Tunisian Landfill Leachate Using Dairy Rejects

Landfilling is one of the most widely used processes for the disposal of municipal solid waste (MSW). It is designed to dispose high quantities of waste at economical costs. Landfill management may pose serious environmental impacts through the discharge of highly polluted wastewater also known as leachate. The treatment of landfill leachates (LFL) is very complicated, expensive and requires various combined process applications due to their high COD and nitrogen levels.