Size methods spray cleaning

Methods of dust removal depend mainly on the particle size of the dust and the temperature and moisture content of the gas. The methods used are broadly divided into dry methods and wet methods. The dry methods involve the use of gravity and baffle chambers, cyclones, filters, and electrostatic precipitators, while the wet methods involve the use of spray towers and venturi scrubbers. In principle, wet cleaning is preferred to dry cleaning because of the excessive wear associated with and the difficulty in handling the fine dusty material removed in the dry methods. The wet methods, however, must be followed by such operations as filtration, drying of filter cakes, and recycling of water. 

Some methods used to clean off gases from incinerators employ catalytic bag filters with the injection of PAG or selective catalytic reduction (for NO removal) in a combination with catalyzed oxidation of the dioxins [ISO]. The use of activated carbon packed in adsorption units or sprayed into flue gas streams together with lime, has become a standard in gas cleaning liom dioxins on all sizes of plants. Typically, the treatment with activated carbon maintains the dioxin emission range below 0.1 ng m [181]. 

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