Comparison of Different Parameters of Four Selected Industrial Effluents in Chittagong Metropolitan, Bangladesh

A study was executed at Nasirabad Industrial Area, Chittagong to compare important parameters of industrial effluents viz. physical, chemical and heavy metals from four types of industries such as steel, textile, chemical and garments. For sample collection three points were selected from each industry-discharging, mixing and universal points. Then all collected samples were analysed by using pH electrode, DO electrode, sension 156 portable multi-parameter meter, and spectrophotometer etc. It revealed that effluents from garment industry were awfully polluted, they exposed the lowest DO value (1.0 mg/L) and highest TDS (512 mg/L), EC (1135 mho/cm) and BOD (76.66 mg/L), COD (326 mg/L), Chromium (0.283 mg/L), Zinc (0.041 mg/L) and Lead (0.69 mg/L). Most of the cases the second point showed surpassing effluents accumulated. Comparatively, steel industry was found less contaminated as-well-as in all industries universal points wherein all parameters showed the values is under standard level due to natural assimilative capacity.