The invention provides a novel
heat pump distillation energy saving process for a desulfurization
solvent in regenerable
flue gas desulfurization. The novel
heat pump distillation energy-saving process comprises the following steps that A, SO2 is separated from a pregnant solution of an SO2-containing desulfuration
solvent at a desulfuration section in a
distillation tower through distillation, and a barren liquor at the bottom of the distillation
tower is sent to a flash
tower, and is flashed in the flash tower; B, flashing steam generated by the flashing is sent to a compressor, and is compressed by using a compressor to act; and C, steam output from the compressor is sent to the bottom in the distillation tower, and forms raising steam required by the distillation together with vaporized water, the raising steam and the pregnant solution falling from the upper part of the distillation tower reversely flow for performing
mass and
heat transfer to complete the distillation process, part of flashed barren liquor and the steam discharged from the top of the distillation tower are exchanged with heat, and the barren liquor returns to the flashing tower after the steam heat is recycled, the left flashed
barrel liquor and the desulfurization
solvent pregnant solution entering the distillation tower are exchanged with the heat, and cooled to 40-55 DEG C through
water cooling after the heat of the barren liquor is recycled so as to be sent to a desulfurization section for being recycled. When the distillation is performed by adopting the
heat pump distillation process, energy can be saved more than 70 percent in comparison with that of a conventional
distillation method.