Choosing Between Agricultural Land Application and Landfilling or Incineration of Municipal Wastewater Biosolids

Abstract

The treatment of municipal wastewater generates residues as a by-product of its processes. Residual biosolids have previously been viewed as liabilities of the treatment process. Currently, however, biosolids are increasingly being put to beneficial reuse as agricultural fertilizer and soil conditioners. This paper tabulates the reasons for the change from disposal methods such as incineration and landfilling to recycling. The reasons for choosing between these methods are analyzed through the use of survey responses from municipal wastewater treatment facility managers. The implications of a change from residue disposal to biosolids reuse are also discussed. The effects of these changes on the wastewater treatment processes utilized, and subsequent management practices are examined. The findings of the study show, that although agricultural land application of municipal wastewater biosolids is ecologically the most beneficial method of disposal, the major consideration in its use is cost. The benefits of land application are used primarily as sales tools to promote the program, however bad public relations, and negative public response have the potential to completely squash a program. The resultant conclusion is, that if costs were relatively equal, landfilling or incineration would be used in spite of the ecological benefits of land application.