Investigating the potential of eggshells as an adsorbent in the treatment of textile wastewater :

Abstract

Treatment of wastewater is One of the biggest problems faced by textile Manufacturers. This is due to the fact that the effluent produced is much, high in Colour, BOD, COD. and Turbidity and yet faced with. a problem of high costs incurred in treating the wastewater, the present study therefore examined the use of powdered eggshell in the removal or colour, turbidity, BOD and COD from textile waste water. So far. a number of efficient methods have been reviewed for the treatment of textile waste water such as. chemical precipitation, ion exchange. Reverse osmosis, ultrafiltration, Nano filtration, coagulation, flocculation and so forth. Adsorption process being very simple, economical, effective and. versatile has become the most preferred methods for removal of toxic contaminants from wastewater. The most commonly used adsorbent is activated carbon which is quite expensive and not readily available especially when it comes to treating a large amount of wastewater as per the case of textile industries. Batch adsorption experiments were used to study the removal of different pollutants from textile wastewater. The main parameters that influenced adsorption onto eggshell were contact time and eggshell dosage. The average initial concentrations of the effluent were found to be 130ptco, 169 NTU, l067mgli and 528mg/l for colour, turbidity, COD&: BOD respectively. The contact time ranged from 30 to 180 minutes while the adsorbent dosage ranged from 1 to 6g. For contact-time, adsorption. increased with increase in contact time and the maximum adsorption was obtained at a percentage of 60.5%, 60.1%.63.9% and 70% for turbidity, colour, COD and BOD respectively at 150minutes with 19 constants at. the start. However, the. other masses Were also varied to establish the optimum contact time which was found to be 150 minutes. The research also gave similar results with adsorbent dosage, where adsorption increased with increasing adsorbent mass because of greater surface area provided with maximum value of 76~6%, 81.2%; 86% &86.1 for turbidity, colour. COD& BOD respectively at 5g (optimum dosage). In conclusion, the rapid uptake and high adsorption capacity achieved. when. the experiments were conducted at contact time, eggshell dosage, shows that eggshell is an attractive alternative adsorbent material for the removal of pollutants from textile wastewater, at a relatively cheaper cost than other conventional treatment methods