Patent · US Expired

Process for gasifying pelletized carbonaceous fuels

US4220454A · kind A · utility

13Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 29, 1978
Grant dateSep 2, 1980
Priority date
Expiry dateDec 29, 1998

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10J2300/1807
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A process is disclosed for gasifying pelletized coal to produce a low Btu gas containing large amounts of hydrogen and carbon monoxide. Advantageously, the process is carried out on a circular traveling grate machine on a continuous basis. A horizontally moving, quiescent, gas-permeable bed of coal is formed by depositing at least one layer of a sized recycle charge of coal and at least one layer of fresh coal. To initiate an oxidizing reaction zone, the surface of one of the layers is ignited and the zone travels as a wave downwardly into the layer and upwardly into any superposed layer. Air and steam or air and carbon dioxide are either updrafted or downdrafted through the bed to control combustion. The coal is reduced in zones ahead of the advancing zone or zones of oxidation, and the reactions are terminated before the oxidation zone reaches both outermost surfaces of the bed to minimize the formation of carbon dioxide. Unreacted coal is separated from fine ash and is used as the recycle feed.

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