Patent · US Expired

Method and apparatus for recycling sewage sludge utilizing spent water-softener lime

US6887389B2 · kind B2 · utility

10Cited by
11References
2Claims
0Family size

Inventor

Key dates

Filing dateOct 23, 2002
Grant dateMay 3, 2005
Priority date
Expiry dateNov 6, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S210/919
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

A method and apparatus are disclosed for mixing sewage sludge with spent water-softener lime in a ratio of approximately 10:1 on a wet basis. The mixture is introduced to a rotary pre-dryer kiln and a rotary combuster kiln to kill pathogens. An ash by-product and gases are thereby produced. The ash by-product can be disposed of at much less cost or can be incorporated in a variety of applications such as an aggregate substitute.

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