Patent · US Expired

Combustion method

US4616576A · kind A · utility

18Cited by
8References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 29, 1985
Grant dateOct 14, 1986
Priority date
Expiry dateMay 29, 2005

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF23C2206/101
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

In a two-stage combustion method first and second circulating fluidizing bed systems are utilized. The first bed system is operated under reducing (sub-stoichiometric) conditions so as to minimize NO.sub.x formation. Solids in the flue gases are separated and returned to the first bed system, while the flue gases are subjected to afterburning in the second bed system. Oxygen containing gas is supplied to the second bed system to effect afterburning, and additionally sulfur absorbing and/or NO.sub.x formation decreasing agents are supplied to the second system. When burning coal, the first system is operated at a temperature of about 700.degree.-1000.degree. C., while the second system is operated at about 600.degree.-950.degree. C. The flue gases may be cooled, just prior to effecting separation of the solids, in one or both of the bed systems.

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