Patent · US Expired

Sewage sludge recycling with a pipe cross-reactor

US6758879B2 · kind B2 · utility

32Cited by
31References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 12, 2000
Grant dateJul 6, 2004
Priority date
Expiry dateDec 12, 2020

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02W30/40
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

An improved process for enhancing the plant nutrient value of relatively low analysis organic waste material (e.g., sewage sludge) involves treating the waste material with an acid and base in a pipe-cross reactor. The process more particularly involves mixing the waste material with water to form a slurry (or initially taking the waste material as a slurry); pumping the slurry to a pipe-cross reactor for reaction with a base, acid, and water to form a melt; spraying the melt onto a recycling bed of fines in a granulator, and flashing off the water contained in the melt as steam; rolling the melt onto recycled fine particles in a granulator to form granulated particles; and drying these granulated particles to form an enhanced plant nutrient value composition (e.g., a fertilizer or soil conditioner having a greater “NPK” value than the original relatively low analysis organic waste material). The invention also includes fertilizers produced according to the improved process, which fertilizers are of the same size and shape and density of commonly used fertilizers. The method advantageously utilizes the heat generated by the exothermic acid-base reaction in the pipe-cros…

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