1183077 - An Industrial Waste Material to Beneficial Coagulant: Application of Carbide Slag to Remove Turbidity from Oilfield Produced Water (Student Poster #18)

Carbide slag is a by-product generated from the hydrolysis process during the manufacturing of acetylene in a wet generator. Disposal of carbide slag is a challenging task, as it can easily contaminate groundwater. It is produced in huge volume and mostly disposed of in landfill sites. This study evaluates the potential of carbide slag as coagulant material for treatment of an oil field produced water. The carbide slag sample was obtained from local industrial plant in semi solid state. It was oven dried for 2 hours at 105oC to obtain carbide slag powder (CSP) and elemental characterization was done using energy-dispersive X-ray fluorescence spectrometry (ED-XRF). ED-XRF results stated that CSP is mainly composed of ~95% CaO, 2-3% SiO2 and 2-3% Fe2O3 and other materials in trace amount. Coagulation experiments were conducted in glass reactor with 100 mL capacity. CSP in six different doses (0.1, 0.2, 0.4, 0.6, 0.8, and 1 g/L) were added to 50 mL oil field produced water with initial turbidity of 101 NTU. Rapid mixing was provided for 30 minutes using magnetic stirrer. Five mL of 0.01 M ferric chloride was used as flocculant to enhance the settling of formatted flocs. Supernatant collected after 30 minutes of settling was analysed using turbidity meter. Control experiment was conducted to observe the sole effect of ferric chloride. The results revealed that CSP act as coagulant, turbidity was reduced by 66-84% at various doses. Maximum removal (14 NTU) was observed at 0.2 g/L CSP dose, which is comparable to other conventional coagulants. Thus, carbide slag can be reused as sustainable coagulant aid for treatment of various wastewaters.