Dual grid catalyst basket and method of independently supporting primary and secondary catalysts
AssigneeThe Alloy Engineering Company
InventorF. Burke Allen
Life of this patent
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Abstract
An ammonia oxidation catalyst basket design has two support grids. A first grid supports the primary catalyst and a separate, second grid supports the secondary catalyst. This dual grid design separates the two catalysts, and enables the catalysts to be independent of each other. Any interruption in the primary or the secondary catalyst does not impede or adversely impact on the structure or function of the other catalyst.
Claims17
A catalyst basket for oxidizing an associated mixture of air and ammonia, the catalyst basket comprising:
- a housing having a first, upstream end that receives the associated ammonia communicates with second, outlet end of the housing;
- a support flange extending from the housing between the first end and the second end of the housing;
- a first support grid supported along a perimeter thereof by the support flange of the housing, the first support grid supporting a primary catalyst that includes a primary catalyst for oxidizing the associated ammonia passing from the first end of the housing through the primary catalyst to produce nitrogen oxides (NOx);
- and
- a separate, second support grid and a mesh screen are mounted to the housing at a spaced location below and downstream of the first support grid, the second support grid and the mesh screen receiving flow from the first support grid and independently supporting a different, secondary catalyst that receives the flow from the first support grid without supporting the primary catalyst and the secondary catalyst limits emissions of nitrous oxide N2O by interacting with the secondary catalyst, the first support grid positioned between the primary catalyst and the secondary catalyst such that the first support grid is located downstream of the primary catalyst and upstream of the secondary catalyst.
A method of oxidizing an associated mixture of air and ammonia in a catalyst basket, the method comprising:
- supplying a housing having an upstream end and an axially spaced downstream end;
- mounting a support flange from the housing between the upstream and downstream ends of the housing;
- mounting a first support grid via the support flange to the housing for supporting a primary catalyst;
- mounting a separate, second support grid to the housing below and downstream of the first support grid, and a mesh screen such that the second support grid and the mesh screen support a secondary catalyst and not supporting the primary catalyst;
- positioning the first support grid between the primary catalyst and the secondary catalyst such that the first support grid is located downstream of the primary catalyst and upstream of the secondary catalyst;
- feeding the associated mixture of air and ammonia through the primary catalyst for reacting therewith in the oxidizing method;
- and
- directing flow from the primary catalyst through the secondary catalyst.
Dependencies are inferred from the claim text.