FATE OF NITROGEN IN SEWAGE EFFLUENT APPLIED TO SOIL

Natural chemical and biological reactions will remove nitrogen from sewage effluent applied to soils if the wastewater is applied in a carefully managed treatment system. Only denitrification can remove the tremendous quantities of nitrogen applied in a high-rate land filtration system where nitrogen loads may be 10 to 30 times greater than those applied in irrigation systems. Columns packed in the laboratory with loamy sand removed 80% of the nitrogen applied at infiltration rates below 6 in./day (15 cm/day). Percent nitrogen removal decreased exponentially as the infiltration rate increased from 6 in./day - 22 in./day (15 cm to 55 cm/day). Nitrogen was also removed by the soil columns when high-nitrate water was collected, mixed with sewage, and recycled. Nitrogen may be removed by applying sewage to soils of low permeability and allowing it to trickle slowly down grassed slopes. Removal is probably due to a combination of plant uptake, denitrification, and immobilization in microbial tissue.

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Filing Info

  • Accession Number: 00125433
  • Record Type: Publication
  • Report/Paper Numbers: ASCE #11570 Proceeding
  • Files: TRIS
  • Created Date: Nov 5 1975 12:00AM