US 12,594,519 B2 · Methods for regenerating a filter medium and cleaning flue gas

Abstract

The invention discloses an efficient medium and low temperature sulfur-containing flue gas denitration device and method based on Fast SCR reaction, and the sulfur-containing flue gas denitration device and method can be used in a utility boiler and flues on the tail portions of various industrial furnace. The sulfur-containing flue gas denitration device comprises an oxidization module used for oxidizing NO and an SCR reaction module used or denitration, part of NO in flue gas is converted into NO2 through the oxidization module and then enters the SCR reaction module, and pre-oxidized flue gas and sprayed NH3 are mixed and enter a selective catalytic reduction layer to conduct rapid SCR reaction. The catalytic reduction layer is made of a low-vanadium loaded vanadium, tungsten and titanium cellular catalyst, and the reaction temperature is 200-350 DEG C. The denitration system has efficient sulfur poisoning resistance and greatly promotes denitration efficiency of the flue gas low-temperature section, it is verified through experiments that under the low-temperature sulfur-containing flue gas atmosphere at the temperature of 250 DEG C, the system has the obvious denitration effect, and the efficiency can reach 90% or more and is kept stable.

Claims20

Dependent claims

A method comprising:

providing at least one filter medium;
wherein the at least one filter medium comprises:
at least one catalyst material;
and
ammonium bisulfate (ABS), ammonium sulfate (AS), or any combination thereof;
flowing a flue gas stream through or by the at least one filter medium;
wherein the flue gas stream comprises:
NOx compounds comprising:
Nitric Oxide (NO), and
Nitrogen Dioxide (NO2);
and
Sulfur Dioxide (SO2);
wherein the flue gas stream is at a first temperature during the flowing step;
increasing NOx removal efficiency of the at least one filter medium;
wherein the increasing of the NOx removal efficiency of the at least one filter medium comprises:
adding ammonia (NH3) in a concentration ranging from 0.0001% to 0.5% of the concentration of the flue gas stream;
and
increasing the temperature of the flue gas stream from the first temperature to a second temperature that exceeds the first temperature;
wherein a concentration of SO2 in the flue gas stream does not exceed 12 ppm during the step of increasing the NOx removal efficiency of the at least one filter medium:
wherein the method regenerates the at least one filter medium.

17 more elements

Dependencies are inferred from the claim text.

Methods for regenerating a filter medium and cleaning flue gas

Life of this patent

Methods for regenerating a filter medium and cleaning flue gas

Life of this patent

Abstract

Claims20