Sago industries effluent containing large amounts of organic content produced excess sludge which is a serious problem in wastewater treatment. In this study ozonation has been employed for the reduction of excess sludge production in activated sludge process. Central composite design is used to study the effect of ozone treatment for the reduction of excess sludge production in sago effluent a...

The control of sludge bulking by ozonation was studied on four parallel pilot-scale (110 l/d) biological nutrient removal systems. Bulking was caused by filamentous organisms which typically occur in nutrient removal systems, i.e. Type 0092, Type 0041 and Microthrix parvicella. Continuous dosing of ozone, at 1; 2 and 4 g O3 /kg mixed liquor suspended solids (MLSS).d resulted in a diluted sludge...

Genotoxicity in wastewater and reclaimed water now is gaining increased attention because of genotoxins' potential damage to the ecosystem and human health. The effect of ozonation on genotoxicity in reclaimed water was investigated. It was found that ozonation decreased the genotoxicy dramatically in three tertiary treatment plants. In the further batch ozonation experiment in laboratory, seco...

The degradation of pesticide Carbendazim was investigated by combination of TiO2-based photocatalysis and ozonation. A batch annular photoreactor has been used for carrying out the combined process and the influence of TiO2 concentration, ozone dose and pH were investigated. The results showed that the removal rate increased with increase in ozone dosage upto 0.48 g/h and decreased above 1g/L o...

Application of ozonation in water treatment involves complex oxidation pathways that could lead to the formation of various by-products, some of which may be harmful to living organisms. In this work, ozonation by-products of ofloxacin (OFX), a frequently detected pharmaceutical pollutant in the environment, were identified and their ecotoxicity was estimated using the Ecological Structure Acti...

Biodegradability enhancement and detoxification of cork boiling wastewater (CBW) are required for the successful implementation of biological treatment options. We studied the possibility of achieving these goals through ozonation pre-treatment by experimenting on the effect of ozone dose and pH. The CBW used had a pH of 5.81, a chemical oxygen demand (COD) of 1,865 mg L(-1), a biochemical oxyg...

This paper compares experimental results on methylene blue (MB) removal systems based on ozone oxidation, zeolite adsorption, and simultaneous adsorption-oxidation using ozone in the presence of natural zeolite. The effect of pH (2-8), and the presence of radical scavengers (sodium acetate) on process rates and removal efficiencies are assessed at laboratory scale. The experimental system consi...

ozonation was carried out for decolorization and coD removal of raw and anaerobically treated uAsb (upflow anaerobic sludge blanket) combined industrial (mainly textile) effluent in a lab-scale bubble column reactor. ozonation of anaerobic bioprocess effluent at a dose of 300 mg/h for 10 min resulted in 81% color and 75% coD removal (100 mgo3/80 mg coD) while for raw wastewater 25 min ozonation...

ABSTRACT: In this project, a nano catalyst (TiO2) and ozone combined with each other and they were used for the removal of 4-nitrophenol (4NP) in industerial wastewater. The effect of some operational parameters such as initial pH (3-9), the concentration of pollutant (20-80 mg/L), and amount of TiO2 were investigated. In O3/TiO2 process, the anion radical  formed before the production of hydro...