Emission control system
Methods of treating mercury contaminated gas comprising: introducing a hydrogen halide selected from HBr and HI into a mercury contaminated gas stream containing a quantity of particulate matter at an introduction rate sufficient to create a concentration of at least 0.1 ppmvd; wherein greater than 50% of all particulate matter in the mercury contaminated gas stream is a native particulate matter; contacting a quantity of active bromine with the native particulate matter; creating a doped particulate matter; coating a filtration media with the doped particulate matter; and passing a portion of the mercury contaminated gas stream through the doped particulate matter on the filtration media and other related methods are disclosed herein.
1. A method of treating mercury contaminated gas comprising:
a. introducing dilute aqueous HBr into a mercury contaminated gas stream containing a quantity of particulate matter at an HBr introduction rate sufficient to create a HBr concentration of at least 0.1 ppmvd;
b. contacting a quantity of active bromine with a portion of the quantity of particulate matter;
c. creating a doped particulate matter from the quantity of active bromine and the quantity of particulate matter; and
d. inducing electrostatic forces thereby removing greater than 50% of the doped particulate matter from the mercury contaminated gas stream.
2. The method of claim 1 wherein mercury is collected on the doped particulate matter.
3. The method of claim 1 wherein the electrostatic forces occur within an electrostatic precipitator.
4. The method of claim 1 wherein the introduction of dilute aqueous HBr is at an introduction rate creating a HBr concentration of at most 10 ppmvd.
5. A method of treating flue gas comprising:
a. introducing active bromine into a treatment zone;
b. introducing ammonia into the treatment zone;
c. passing a quantity of flue gas having an initial ash content and having an initial mercury content through the treatment zone;
d. collecting at least 80% of the initial ash content in a particulate control device; and
e. collecting at least 50% of the initial mercury content in the particulate control device.
6. The method of claim 5 wherein the ash collected in the particulate control device has a total ammonia content of at least 40 ppm by weight.
7. The method of claim 5 wherein the ash collected in the particulate control device contains at least 60% of the initial mercury content.
8. The method of claim 5 wherein the introducing of active bromine into the treatment zone is at an introduction rate creating an active bromine concentration of between 0.1 ppmvd and 10 ppmvd.