Process using MN method to remove SO2 in industrial waste gas

The invention discloses a process using an MN method to remove SO2 in industrial waste gas. The process comprises the following steps: preheating MN slurry with a concentration of 4-6% to 40-50 DEG C, conveying the slurry to the top of a desulfurization tower through a conveying pump, spraying down the slurry through a jet, wherein the slurry is in contact and reacts with the counter flow of treated and dedusted flue gas sent in from the bottom of the tower; emptying SO2-removed tail gas; conveying desulfurized slurry into a separator for filtering and separation, wherein the separated liquid is conveyed in to prepare MN slurry for repeated use, the separated solid is conveyed to a regenerator and degraded to MN and SO2 at the temperature of 100-200 DEG C; the MN is recycled and the SO2 is sent for sulfur acid preparation; and the absorption and desulfurization temperature is about 45 DEG C and the liquid-gas ratio is 15 L/m . The process is not high in reaction temperature; the MN slurry can be preheated with residual heat of waste gas, so as to reduce the energy consumption of desulfurization; the desulfurization agent MN can be recycled; the regenerated SO2 after desulfurization can be used for preparing a sulfur acid product; no waste is generated except gas phase; both cost and energy consumption are relatively low; and the process is simple and feasible in procedures and the desulfurization requirement of flue gas or waste gas of medium and large scale industries can be met.