Mineral play key role in development of world. Demand of metals increasing day by day due to increasing of manufacturing production. After mining, metal are extracted from ore, metal and extraction of metals is increasing day by day. During extraction of metals from ore in metal industry flue gases emitted which comprises of many toxic component. In this study we have gone through a real problem of industry. Cyanide is most toxic in flue gases of metallurgical industry which polluted environment and creating health issue. A plant is producing 200,000 metric ton of metal per year and 2363 Kg/hr of flue gas with 54,794,520 mg/hr of cyanide. This quantity of cyanide is very high and above EPA and OSHA standards. Alkaline scrubbing used in which NaOH used alkaline scrubbing agent due to its cheap then KOH. Use of plastic packing shows good results because it does not react with alkaline material. Cyanide reduced to 20,092mg/hr or 0.2mg/m3 is not effected environment.