Aluminum melting furnace flue gas dedusting and desulfurization system

The invention discloses an aluminum melting furnace flue gas dedusting and desulfurization system, the aluminum melting furnace flue gas dedusting and desulfurization system comprises an aluminum melting furnace, a desulfurization dedusting filter, a heat water exchange tank, a draught fan and a chimney which are in turn connected, the desulfurization dedusting filter is provided with a plurality of filter beds, the filter bed is provided with an adsorption agent layer, a coarse granular layer, a fine particle layer and a catalyst layer in turn from up to down along the flue gas passing-through direction, an adsorption agent of the adsorption agent layer is prepared from the following method: adding fly ash, calcium hydroxide, sodium hydroxide and aluminum oxide in the weight ratio of 20:15-25:0.5-1.5:1-3 into water for water bath heating to 70 to 80 DEG C for hydration for 10-14 hours, then filtering, putting a solid into an oven at 200 DEG C, heating and drying for 2 hours, and grinding to obtain the adsorption agent. After flue gas of the aluminum melting furnace passes through the system, the dust removal rate is 98.8%, and the desulfurization efficiency is 80% or above at 700-850 DEG C.