Aerosol deposition apparatus, method, and filter body with deposits
Apparatus and methods are disclosed which apply inorganic particles to a plugged honeycomb body comprising porous walls, an inlet end and an outlet end. The apparatus comprises a Venturi tube through which the particles flow into a duct system. Filtration articles comprise: a plugged honeycomb body; inorganic deposits disposed within the plugged honeycomb filter body having a porosity in a range of greater than 95% to less than or equal to 99.9% and an average thickness in a range of greater than or equal to 0.5 μm to less than or equal to 50 μm; and a clean filtration efficiency of greater than or equal to 85% as measured by a smoke filtration efficiency test.
1 . An apparatus configured to apply inorganic particles to a plugged honeycomb body comprising porous walls, an inlet end and an outlet end, the apparatus comprising:
a duct spanning from a first end to a second end;
a deposition zone configured to house the plugged honeycomb body and in fluid communication with the second end of the duct;
an inlet conduit in fluid communication with the duct, the inlet conduit upstream from the deposition zone;
an inorganic particle source in fluid communication with the inlet conduit and configured to supply inorganic particles to the inlet conduit;
a delivery conduit configured to receive the inorganic particles from the inorganic particle source;
a drying apparatus positioned upstream from the delivery conduit and configured to dry the inorganic particles;
an aerosol generator comprising a Venturi tube comprising a first end and a second end in fluid communication with the inlet conduit, the aerosol generator configured to deliver an aerosol comprising the inorganic particles and air to the deposition zone; and
a flow generator in fluid communication with the duct and the deposition zone, the flow generator configured to establish a flow of a gas and the inorganic particles introduced into the duct.
2 . The apparatus of claim 1 , wherein the delivery conduit comprises a flared first end configured to receive the inorganic particles from the inorganic particle source.
3 . The apparatus of claim 2 , wherein the delivery conduit further comprises a second end connected to the first end of the Venturi tube, the apparatus further comprising a pressurized gas source in communication with the inlet conduit.
4 . The apparatus of claim 3 , wherein the Venturi tube comprises a reduced cross-sectional area portion between the first end and the second end of the Venturi tube.
5 . The apparatus of claim 1 , wherein the apparatus further comprises an inorganic particle feed system configured to deliver inorganic particles from the inorganic particle source to the inlet conduit.
6 . The apparatus of claim 5 , wherein the inorganic particle feed system comprises a conveyor.
7 . The apparatus of claim 1 , wherein the drying apparatus comprises a drying lamp.
8 . The apparatus of claim 1 , further comprising a roller positioned upstream from the delivery conduit, the roller configured to reduce agglomerates that enter the delivery conduit.
9 . The apparatus of claim 1 , wherein the flow generator comprises a fan.
10 . The apparatus of claim 9 , wherein the fan is positioned at the inlet end of the duct and upstream from the inlet conduit.
11 . The apparatus of claim 10 , further comprising a homogenizer plate configured to homogenize flow through the duct.
12 . The apparatus of claim 1 , further comprising a first pressure sensor located upstream from the deposition zone and a second pressure sensor downstream from the deposition zone, the first pressure sensor and the second pressure sensor in communication with a processor which measures a differential pressure between the first pressure sensor and the second pressure sensor.