The invention relates to an
exhaust gas dedusting, denitration and desulfuration method for a thermal power
plant. According to the invention, after being dedusted firstly by a bag-type
dust collector, high-temperature raw
exhaust gas is introduced in an SCR (
selective catalytic reduction) reactor for performing SCR for realizing denitration, and then, the
exhaust gas subjected to denitration passes through an
air preheater and a
heat exchanger in sequence to be cooled to 90-100 DEG C, and then is subjected to wet desulfuration in a desulfurizer; and the exhaust gas subjected to desulfuration and discharged from the desulfurizer is heated to 100-105 DEG C by the
heat exchanger and then enters a
chimney to be discharged. In the bag-type
dust collector, filter cloth in a filter bag has base cloth which is PBO (Poly-p-phenylenebenzobisthiazole)
fiber woven cloth and has two surface
layers referring to composite fibrofelts formed by cross-laying of PBO
fiber nets and
basalt fiber nets, the base cloth is sandwiched between the two surface
layers and sewed up into a
whole body, the
whole body is subjected to hot rolling, singeing and heat shaping, Teflon dipping and
drying to finally form high-temperature resistant filter cloth. By the adoption of the high-temperature resistant filter bag, the raw exhaust gas can be dedusted firstly at a high temperature and then is subjected to denitration, therefore, ash
fouling of subsequent equipment and damages to a catalyst can be reduced, and the effects of low catalyst consumption and high denitration efficiency can be achieved; and since the catalytic reaction does not need additional heat, the effects of energy saving and emission reduction are achieved.