Patent · US Expired

Use of high carbon coal ash

US6755905B2 · kind B2 · utility

72Cited by
10References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 15, 2002
Grant dateJun 29, 2004
Priority date
Expiry dateSep 2, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P40/125
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

A synthetic slag is produced by a high temperature combustion reaction between coal ash having a high carbon content, and a source of lime such as cement kiln dust. The carbon content of the coal ash is oxidized by oxygen gas, which typically is derived from air or an air/oxygen combination in an exothermic reaction and the heat generated is exploited in the melting process. In this way the gaseous products will typically comprise nitrogen, unreacted oxygen and carbon dioxide, and heat energy can be readily recovered from the hot off gas products evolving during the combustion reaction. The synthetic slag may be pelletized and employed as lightweight mineral aggregate or milled to cement fineness to provide slag cement.

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