Catalyzed ceramic candle filter and method of cleaning process off- or exhaust gases

Patent metadata

Field	Value
Publication number	US-10076743-B2
Application number	US-201515545477-A
Country	US
Kind code	B2
Filing date	Mar 20, 2015
Priority date	Mar 20, 2015
Publication date	Sep 18, 2018
Grant date	Sep 18, 2018

Abstract

Ceramic candle filter and use of the filter in the removal of particulate matter in form of soot, ash, metals and met-al compounds, together with hydrocarbons and nitrogen oxides being present in process off-gas or engine exhaust gas, the filter includes a combined SCR and oxidation catalyst being arranged on the dispersion side and within wall of the filter; and a palladium including catalyst arranged on the permeation side and within wall of the filter facing the permeation side.

First claim

The invention claimed is:

1. A ceramic candle filter suitable for the removal of particulate matter in form of soot, ash, metals and metal compounds, together with hydrocarbons and nitrogen oxides being present in process off-gas or engine exhaust gas, the filter comprises a combined SCR and oxidation catalyst arranged at least on the dispersion side and/or within wall of the filter; and a palladium comprising catalyst arranged on the permeation side of the filter and within wall of the filter facing the permeation side.

2. The ceramic candle filter of claim 1 , wherein the combined SCR and oxidation catalyst comprises a vanadium oxide and titania.

3. The ceramic candle filter of claim 1 , wherein the palladium comprising catalyst further comprises a vanadium oxide and titania.

4. The ceramic candle filter of claim 1 , wherein the palladium comprising catalyst contains palladium in an amount of between 20 and 1000 ppm/weight of the filter.

5. The ceramic candle filter according to claim 1 , wherein the ceramic material of the filter is selected from the group of silica-aluminate, calcium-magnesium-silicates, calcium-silicates fibers, or a mixture thereof.

6. The ceramic candle filter according to claim 5 , wherein the ceramic material of the filter consists of bio-soluble fibres selected from the group of calcium-magnesium-silicates.

7. A method for the removal of particulate matter in form of soot, ash, metals and metal compounds, together with hydrocarbons and nitrogen oxides being present in process off-gas or engine exhaust gas, comprising the steps of
providing a process off-gas or engine exhaust gas containing a nitrogenous reductant or adding the nitrogenous reductant to process off- or exhaust gas;
passing the off- or the exhaust gas to a ceramic candle filter and capturing the particulate matter on dispersion side of the filter;
reducing amounts of soot in the particulate matter captured on the dispersion side of the filter and reducing amounts of hydrocarbons in the off- or exhaust gas by oxidation and reducing amounts of nitrogen oxides by selective catalytic reduction (SCR) of the nitrogen oxides with the nitrogenous reductant in contact with a combined SCR and oxidation catalyst being arranged on the dispersion side and/or within wall of the filter; and
passing the gas through the wall of the filter and reducing amounts of carbon monoxide and ammonia in the gas passing through the filter wall by contact with a palladium comprising catalyst arranged on the permeation side of the filter and/or within the wall of the filter facing the permeation side.

8. The method of claim 7 , wherein the combined SCR and oxidation catalyst comprises a vanadium oxide and titania.

9. The method according to claim 6 , wherein the palladium comprising catalyst further comprises a vanadium oxide and titania.

10. The method according to claim 6 , wherein wherein the palladium comprising catalyst contains palladium in an amount of between 20 and 1000 ppm/weight of the filter.

11. The method according to claim 6 , wherein the ceramic material of the filter is selected from silica-aluminate, calcium-magnesium-silicates, calcium-silicates fibers, or mixtures thereof.

12. The method according to claim 6 , wherein the ceramic material of the filter comprises bio-soluble fibres selected from the group of calcium-magnesium-silicates.

Assignees

• Haldor Topsoe As

Inventors

• Castellino Francesco
• Pedersen Lars Storm

Classifications

• B01D2255/20707

  Titanium · CPC title

• B01D53/9418

  for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas · CPC title

• B01D53/8643

  Removing mixtures of carbon monoxide or hydrocarbons and nitrogen oxides · CPC title

• B01J23/22

  Vanadium · CPC title

• F01N2510/068

  characterised by the distribution of the catalytic coatings · CPC title