Treatment of landfill leachate using an aerated, horizontal subsurface-flow constructed wetland

Sci Total Environ. 2007 Jul 15;380(1-3):19-27. doi: 10.1016/j.scitotenv.2006.12.030. Epub 2007 Jan 22.

Abstract

A pilot-scale subsurface-flow constructed wetland was installed at the Jones County Municipal Landfill, near Anamosa, Iowa, in August 1999 to demonstrate the use of constructed wetlands as a viable low-cost treatment option for leachate generated at small landfills. The system was equipped with a patented wetland aeration process to aid in removal of organic matter and ammonia nitrogen. The high iron content of the leachate caused the aeration system to cease 2 years into operation. Upon the installation of a pretreatment chamber for iron removal and a new aeration system, treatment efficiencies dramatically improved. Seasonal performance with and without aeration is reported for 5-day biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD), ammonia nitrogen (NH(4)-N), and nitrate nitrogen (NO(3)-N). Since winter air temperatures in Iowa can be very cold, a layer of mulch insulation was installed on top of the wetland bed to keep the system from freezing. When the insulation layer was properly maintained (either through sufficient litterfall or replenishing the mulch layer), the wetland sustained air temperatures of as low as -26 degrees C without freezing problems.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Ammonia / chemistry
  • Climate
  • Environmental Restoration and Remediation / methods*
  • Iowa
  • Oxygen Compounds / chemistry
  • Waste Disposal, Fluid / methods*
  • Water Pollutants, Chemical / chemistry*
  • Water Pollution, Chemical*
  • Water Purification / methods
  • Wetlands*

Substances

  • Oxygen Compounds
  • Water Pollutants, Chemical
  • Ammonia