**10. Control of heavy metals pollution in exhaust gases**

Study showed that heavy metals show different fate. The control devices which are used in incinerators and other pollution control devices. Some heavy metals like cadmium and plumbum stick in fabric filter ash while chromium, copper and nickel were predominant in the ash present in bottom of the boiler. Zn was found at the bottom and in the ash of fabric filter with a ratio of 07: 03. Though, very minute Hg was found furnace ash, boiler, and SDR and fabric filter; most of Hg crossed through the fabric filter and occurred in an oxidized form. The wet scrubber showed high level control efficacy for mercury which is oxidized, and the addition of commercial stimulated carbon at a rate of 0.2 g/Sm3 resulted in 93.2% mercury removal efficiency [76]. One study revealed that, a high-gravity method using alkaline wastes, i.e., fly ash from petroleum coke, was planned for control of air pollution, containing NOX, CO2 and aerosols. Further reacted fly ash can be used for additional cementations material [77].
