Abstract
The removal efficiencies for chemical oxygen demand (COD), ammoniacal nitrogen (NH3–N), and color, as well as ozone consumption (OC) from the Malaysian semi-aerobic landfill stabilized leachate using ozone reactor, were investigated. Central composite design with response surface methodology was applied to evaluate the interaction and relationship between operating variables (i.e., ozone dosage, COD concentration, and reaction time) and to develop the optimum operating condition. Based on statistical analysis, Quadratic models for the four responses (COD, NH3–N, color, and OC) proved to be significant with very low probability values (<0.0001). The obtained optimum conditions were 70 g/m3 ozone, 250 mg/l COD, and 60 min reaction time. The results obtained by the predicted model were 26.7, 7.1, and 92 % removal for COD, NH3–N, and color, respectively, with 9.42 (kgO3/kg COD) OC. The predicted results fitted well with the results of the laboratory experiment.
Highlights
Sanitary landfill is recognized as the most common and desirable method for eliminating urban solid waste
The results obtained by the predicted model were 26.7, 7.1, and 92 % removal for chemical oxygen demand (COD), NH3–N, and color, respectively, with 9.42 ozone consumption (OC)
The generation of leachate is mainly caused by a release from waste due to successive biological, chemical, and physical processes of waste deposited in a landfill
Summary
Sanitary landfill is recognized as the most common and desirable method for eliminating urban solid waste. It is considered as the most economical and environmentally acceptable method for eliminating and disposing of municipal and industrial solid wastes (Tengrui et al 2007). Sanitary landfill generates a large amount of heavily polluted leachate (Zazouil and Yousefi 2008). Leachate generated from mature landfills (age[10 years) is typically characterized by large amounts of organic contaminants measured as chemical oxygen demand (COD), biochemical oxygen demand (BOD5), ammonia, halogenated hydrocarbons suspended solid, significant concentration of heavy metals, and many other hazardous chemicals identified as potential sources of ground and surface water contamination (Schrab et al 1993; Christensen et al 2001; Renou et al 2008; Aziz et al 2009; Foul et al 2009). Many environmental specialists are determined to find efficient treatments for large quantities of polluted leachate
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
