Flue gas purifying device and method

The invention provides a flue gas purifying device which further comprises a first-stage absorbent spraying device, a second-stage absorbent spraying device, an adsorbent cabin and an adsorbent quantitative supply device; the first-stage absorbent spraying device is arranged on an inlet flue of an SCR reactor, and the second-stage absorbent spraying device is arranged on an outlet flue of the SCR reactor. According to the method and device provided by the invention, SO3 in flue gas is controlled in sections and HCl and HF in the flue gas are synchronously removed, and meanwhile, adverse effects such as wear, ash deposition and blockage on an SCR catalyst and air pre-heater by adding a lot of adsorbent in a single stage are avoided, the adsorbent and the flue gas are fully and uniformly mixed, and the adsorbent is prevented from being settled; the utilization ratio of the adsorbent and the removal efficiency of the system are improved. 本发明提供了种烟气净化装置，所述烟气净化装置还包括：第级吸收剂喷入装置、第二级吸收剂喷入装置、吸收剂仓与吸收剂定量供应装置；所述SCR反应器入口烟道上