Patent · US Expired

Lime kilns

US4948364A · kind A · utility

6Cited by
14References
4Claims
0Family size

Inventor

Key dates

Filing dateSep 9, 1988
Grant dateAug 14, 1990
Priority date
Expiry dateSep 9, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P40/45
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

An annular, vertical shaft kiln comprising a cascading process path with varying cross sectional area, in which the coarse charge particulants tend to follow the longer path near the walls as does the gas being injected into the mid-region of the kiln, while the fine particulants tend to take the straighter, shorter path near the middle, thus resulting in an even calcination of varying diameters of charge particulants. The briquetted fuel which may be made of hazardous waste, is heated slowly to safely destroy such wastes in the processing. Because of the limited range of the ratio of the smallest to the largest diameter of the charge particulants, the charge particulants are sorted through wire mesh screens into bins according to diameter. The kiln's computer then receives data on the process at various points along the path and controls the process by regulating the charge particulants injection, the rate of the fuel injection and/or the speed of the air injection.

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