Venturi/Vortex Scrubber and Pushed Liquid Recirculation System for Controlling/Recycling Chromium Electroplating Emissions

Abstract

This Environmental Security Technology Certification Program (ESTCP) project demonstrated control technology for chromium air emissions. Chromium electroplating is an essential process for the U.S. Department of Defense (DoD) because chromium provides a surface coating with a combination of properties that are very difficult to substitute on military hardware. Unfortunately, the process is highly inefficient and byproduct gases rise as bubbles and burst at the surface to create an airborne mist of chromic acid particulates/droplets. Hexavalent chromium is a known carcinogen and these emissions are strongly regulated. The Venturi/Vortex Scrubber Technology (VVST) was the first air pollution control option developed under this project. The VSST was designed to collect the bubbles before they burst by recycling electroplating fluid through a unit that subjects the fluid to changes in flow direction to coalesce and separate the entrained gases. This technology was to be demonstrated and validated at two military industrial installations. However, the VVST failed during the initial trial. A second technology, the Pushed Liquid Recirculation System (PLRS) emerged through major program and design changes. The PLRS employs jets placed just below the liquid surface in the electroplating bath to induce a surface flow pattern which pushes the bubbles towards the ventilation hood at one side of the tank thereby reducing the effective tank surface area that requires ventilation by conventional control devices. This system is not an alternative control option but rather an additional unit that reduces the flow rate requirements of conventional ventilation systems. The PLRS was demonstrated, by modifying an active electroplating bath at only one site, the Marine Corps Logistics Base (MCLB) in Albany, Georgia.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1999
Accession Number
ADA607429

Entities

People

  • Bruce Holden
  • K. J. Hay
  • Norman Helgeson
  • Shaoying Qi

Organizations

  • Engineer Research and Development Center

Tags

Communities of Interest

  • Biomedical
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force Facilities
  • Air Pollutants
  • Air Pollution
  • Chromium
  • Control Systems
  • Department Of Defense
  • Detection
  • Electronic Mail
  • Electroplating
  • Emission
  • Engineering
  • Environmental Protection
  • Environmental Security
  • Health
  • Hygiene
  • Industrial Hygiene
  • Scrubbers

Readers

  • Environmental Engineering.
  • Internal Combustion Engine (ICE) Technology.
  • Surface Engineering/Surface Coating Technology.