Patent · US Expired

Zero NOx gaseous passivation process

US6612249B2 · kind B2 · utility

7Cited by
24References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 16, 2001
Grant dateSep 2, 2003
Priority date
Expiry dateMar 16, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E20/32
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A method for reducing NOx and/or CO/CO2 emissions from the combustion of coal products or hydrocarbons. One or more curtains of particulate elemental iron, in the form of flakes or the like, are fanned across the combustion chamber and/or the exiting flue gas stream while it is still at high temperature. Moreover, in a coal-fired furnace or boiler, particulate magnetite can be injected e.g. into a region just above the coal which will effectively sequester Hg and heavy metals at a location below a “rag layer” combustion zone in the vicinity of which iron is injected. Suitable particulate elemental iron can be expediently provided at the site by using a grinding wheel or the like to create thin flakes of elemental iron from a wire or rod. Some iron may also adsorb mercury via “red iron” formation and be removed along with solid oxides, iron carbide and siderite via the ash chute of a boiler. Any particulates carried downstream in the flue gas stream are removed, prior to reaching the stack, by cyclones, scrubbers, precipitators or the like.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.