Dielectric barrier discharge-based investigation and analysis of wastewater treatment and pollutant removal.

Current research reveals that the oxidation by ozone is considered as an effective solution and offers irrefutable advantages in wastewater treatment. It is also well known that ozone is used to treat different types of water due to its effectiveness in water purification and for its oxidation potential. This process of ozonation is becoming progressively an alternative technology and is inscribed in a sustainable development perspective in Algeria. In this regards, the present paper investigates the wastewater treatment process by ozone produced by dielectric barrier discharge (DBD) under high potential. Three (DBD) ozone generators of cylindrical form have been used, at a laboratory scale, for treating collected samples from the wastewater treatment plant (WWTP) of the city of Sidi-Bel-Abbes located in the west of Algeria. Our experimental results reveal the efficiency of this type of treatment on the basis of the physicochemical analysis (pH, turbidity, chemical oxygen demand, biological oxygen demand, heavy metals) and microbial analysis downstream of the WWTP, which showed a high rate of elimination of all the parameters.

Physicochemical characterization of sewage sludge and green waste for agricultural utilization.

In order to valorize the organic wastes, a mixture composed of 60 kg of thick sewage sludge from a wastewater treatment plant, 30 kg of green wastes (made of 10 kg straw of wheat, 10 kg manure farm wastes, and 10 kg of dead leaves), and 10 kg of wood chips was prepared. The organic wastes were mixed and put into a wooden cubic composter having a volume of 1.5 m3. Physicochemical analyses were made every 30 days for five months. The results of the analyses showed that the obtained compost had good physicochemical quality and can be used as an organic fertilizer. The main characteristics of this compost were distinguished by its pH from 7.4 to 7.8, with a ratio of organic matter of 40-42%. During composting, the humification process led to an increase in humic acids from 29.5 to 39.1 mg g(-1), a decrease in fulvic acids from 32.1 to 10.9 mg g(-1), and a global decomposition of hemicellulose, cellulose, and lignin. The obtained results show that a period of 150 days of composting gave a C/N ratio of 15.4. The total metal content in the final compost was much lower than the standard toxic levels for composts to be used as good soil fertilizers. The germination index for the two plants Cicer arietinum and Hordeum vulgare was 93% after the same period of composting, showing that the final compost was not phytotoxic. The study showed the possibility of valorization of the compost and its possible use in the domain of agriculture.