Chemical Oxygen Demand (COD) Reduction in Domestic Wastewater by Fly Ash and Brick Kiln Ash

Abstract

The potential of fly ash, brick kiln ash and commercial activated carbon is determined for the reduction of chemical oxygen demand (COD) from domestic wastewater. Laboratory experiments are conducted for investigating the effect of treatment time, adsorbent dose, pH of the media, initial COD concentration, agitation speed and particle size of adsorbents on the COD reduction from the domestic wastewater. Starting with an initial COD concentration of 1080 mg/l the maximum COD reduction achieved for fly ash was 87.84%, brick kiln ash was 83.22% and commercial activated carbon was 99.35 %. These values were achieved when the wastewater was treated with activated carbon for 180 min, fly ash 250 min and brick kiln ash 300 min and the adsorbent dose was kept respectively at 40 g/l, 60 g/l and 45 g/l for activated carbon, fly ash and brick kiln ash. Agitation speed was kept constant at 600 rpm and the pH was maintained at 2 for activated carbon and fly ash and 5 for brick kiln ash. The maximum percent reduction is for 0.053 mm for smaller size of the particles. Though the adsorption capacity of the ash for reducing the COD is lower than that of the commercial activated carbon, the low material cost can make it an attractive option for the treatment of domestic wastewater.

Innovative Technology of COD and BOD Reduction from Coffee Processing Wastewater Using Avocado Seed Carbon (ASC)

“…Adsorption-based technique Devi and Dahiya 2006) developed with low-cost carbonaceous materials showed good potential, more so for chemical oxygen demand (COD) removal from domestic wastewater. Such adsorption approach can offer an easy and economic solution to these environmental challenges.…”

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“…It has been reported that removal efficiencies for organic compounds increase with decreasing of the sorbents particle size [3][4][5]. In this experiment (Fig.…”

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