Apparatus, system, and method for filtration of a dosing fluid in an exhaust aftertreatment system
View Patent ↗An apparatus, system, and method are disclosed for a filter for filtering a dosing fluid in an exhaust aftertreatment system. The filter may comprise a dosing tank configured to contain a dosing fluid, a filter media disposed within the dosing tank, and a support structure supporting the filter media to form a pathway for a flow of dosing fluid. Beneficially, the apparatus, system, and method of the present invention reduce the cost of operation and manufacture of the SCR system.
1. A method for filtering a mono-nitrogen oxide (NO x ) reducing agent in an exhaust aftertreatment system to chemically reduce pollutants in an exhaust stream, the method comprising:
containing a mono-nitrogen oxide (NO x ) reducing agent in a dosing tank, the dosing tank containing a filter media and a heating element within the dosing tank exposed to the mono-nitrogen oxide (NO x ) reducing agent;
transferring heat from the heating element through the mono-nitrogen oxide (NO x ) reducing agent to the filter media;
urging the mono-nitrogen oxide (NO x ) reducing agent through the filter media; and
causing the mono-nitrogen oxide (NO x ) reducing agent to exit the dosing tank, after the mono-nitrogen oxide (NO x ) reducing agent has passed through the filter media.
2. The method of claim 1 , further comprising heating the mono-nitrogen oxide (NO x ) reducing agent within the dosing tank.
3. The method of claim 1 , further comprising pumping the mono-nitrogen oxide (NO x ) reducing agent through a recirculation line.
4. The method of claim 1 , wherein the mono-nitrogen oxide (NO x ) reducing agent is at least one of urea and ammonia.
5. The method of claim 1 , wherein the filter media comprises a plurality of layers defining a gradient density depth filter.
6. The method of claim 5 , wherein a porosity of the gradient density depth filter decreases in a flow direction of the mono-nitrogen oxide (NO x ) reducing agent.
7. The method of claim 1 , wherein the filter media comprises multiple meltblown layers of varying porosity.