Process for treating waste from the production of energetics

US7445717B2 · kind B2 · utility

Assignee

• The United States of America as represented by the Secretary of the Army · US

Inventors

• Daniel K. Cha · Newark, US
• Seok-Young Oh · Newark, US
• Pei Chiu · Hockessin, US
• Byung-Joon Kim · Daejeon, KR

Key dates

• Filing date: Sep 8, 2005
• Grant date: Nov 4, 2008
• Expiry date: Jul 19, 2026

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S588/90
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

A waste stream is treated in a pre-filter having media, preferably sand, connected below a zero-valent metal column reactor incorporating a metal with reducing potential, preferably elemental iron (Fe0); the combination preferably configured as a single unit. The waste stream is pumped through the pre-filter to trap solids and deoxygenate it, then enters the reactor and is subjected to a reducing process. Most of the Fe0 is transformed to the ferrous ion (Fe+2), mixed with the reduced product, and fed to a continuous stirred tank reactor (CSTR) in which Fenton oxidation occurs. The output is then sent to a sedimentation tank and pH-neutralized using a strong base such as sodium hydroxide (NaOH). The aqueous portion is drawn off and the sludge pumped from the sedimentation tank. The system is monitored and controlled to optimize required additives, while monitoring of pressure drop across the pre-filter and column reactor establishes replacement requirements.