Process for efficiently removing oxides of nitrogen from exhaust gas
OwnerWerner Henkeinventor
Life of this patent
Estimating the term…
Abstract
A system for removal of oxides of nitrogen from the waste gas produced by various combustion processes discloses thoroughly mixing the waste gas with ammonia by means of a static mixing element and then passing the resultant mixture through a catalytic reactor. The ammonia may be supplied by reacting a portion of the waste gas with natural gas in the presence of a catalyst.
Claims5
A process for the removal of nitrogen oxides from a hot waste gas of a temperature of at least 420.degree. F. and containing nitrogen oxides, comprising:
- dividing the waste gas into a first, second and third portion;
- passing said third portion through a cooling loop;
- adding a methane containing gas mixture to said second portion so as to convert part of said second portion into at least the amount of ammonia required for stoichiometric reaction with the nitrogen oxides in the waste gas;
- combining said first, third and ammonia containing second portion;
- thoroughly mixing said combination until said combination is substantially thermally and compositionally homogeneous by passing said combination through a static mixing element;
- and
- passing the thoroughly mixed combination over a catalyst that catalyzes the reduction of nitrogen oxides to gaseous nitrogen in the presence of ammonia.
A process for the removal of nitrogen oxides from a hot waste gas of a temperature of at least 420.degree. F. and containing nitrogen oxides, comprising:
- dividing the waste gas into a first, second and third portion;
- passing said third portion through a cooling loop;
- re-combining said first and third portion;
- thoroughly mixing said re-combination until said recombination is thermally homogeneous by passing said re-combination through a first static mixing element;
- adding a methane containing gas mixture to said second portion so as to convert part of said second portion into at least the amount of ammonia required for stoichiometric reaction with the nitrogen oxides in the waste gas;
- combining said re-combined and thermally homogenized first and third portion with said ammonia containing second portion;
- thoroughly mixing said second combination until said second combination is substantially thermally and compositionally homogeneous by passing said second combination through a second static mixing element;
- and
- passing the thoroughly mixed second combination over a catalyst that catalyzes the reduction of nitrogen oxides to gaseous nitrogen in the presence of ammonia.
Dependencies are inferred from the claim text.