page 537 |
Previous | 1 of 8 | Next |
|
|
Loading content ...
57 LAND APPLICATION OF WATER PLANT SLUDGES Brian A. Dempsey, Assistant Professor James DeWolfe, Graduate Research Assistant Douglas Hamilton, Graduate Research Assistant Yuanjyh Lee, Graduate Research Assistant Roni Liebowitz, Graduate Research Assistant Department of Civil Engineering Herschel A. Elliott, Associate Professor Department of Agricultural Engineering The Pennsylvania State University University Park, Pennsylvania 16802 INTRODUCTION Most municipal and industrial waters are produced by conventional treatment processes, which include the addition of a coagulant during a rapid mixing period, flocculation of solids during a slow mix period, and then separation of the solids by means of sedimentation and filtration processes. Two decades ago most of the sludges produced during conventional water treatment were returned to a watercourse without further treatment. This often resulted in severe detrimental impact to the watercourse, since the sludges contained both the original solids from the watercourse plus new solids generated during treatment and also because the disposal was irregular, with large flows during backwash of the filter or from intermittent cleaning of sedimentation basins. In many cases the sludge was disposed into a smaller watercourse than the source of the water. As a result, the EPA decided that the sludges from municipal and industrial water treatment must be treated in a responsible fashion. Presently, the favorite options for disposal of water plant sludges (WPS) are lagoon storage (usually a temporary solution), landfill (which requires substantial dewatering and may present liability problems, especially for co-disposal), and dumping into sanitary sewers (which often creates an undesirable load on sewage treatment facilities). Land disposal is another option but one that has been used infrequently. State governments usually have primacy regarding the land application of WPS; most state governments are experienced regarding land application of sewage sludge but do not know how to deal with land application of WPS. The lack of regulatory expertise regarding WPS is not surprising. Basic data about the chemical nature of WPS are quite sparse. The literature contains substantial information regarding dewatering of WPS, but almost no data regarding the elemental composition and speciation, the phytotoxicity or microbial toxicity of WPS, and the effects of WPS on the physical and nutrient status of soil. These issues are addressed in this chapter. The goal of this work is to add to the scientific data base regarding WPS so that the reactivity of the sludge (especially, in this case, during land application) can be predicted. More specifically, the following issues are addressed: • What is the impact of WPS on the nutrient status of the soil? • What are the concentrations and reactivities of trace metals in WPS? • What are the other issues that should be used to predict proper loadings of WPS on soils? A COMPARISON OF WATER PLANT SLUDGE AND SEWAGE SLUDGE Sewage sludge contains substantial reactive concentrations of nitrogen and phosphorus, trace elements, and tilth-building organic material. As a result sewage sludge has been used as a soil amendment for millennia. The biggest historical problem has been the spread of pathogens. Since the 44th Purdue Industrial Waste Conference Proceedings, © 1990 Lewis Publishers, Inc., Chelsea, Michigan 48118. Printed in U.S.A. 537
Object Description
Purdue Identification Number | ETRIWC198957 |
Title | Land application of water plant sludges |
Author |
Dempsey, Brian A. DeWolfe, James Hamilton, Douglas Lee, Yuanjyh Liebowitz, Roni Elliott, Herschel A. |
Date of Original | 1989 |
Conference Title | Proceedings of the 44th Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://e-archives.lib.purdue.edu/u?/engext,40757 |
Extent of Original | p. 537-544 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Date Digitized | 2009-08-18 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page 537 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Transcript | 57 LAND APPLICATION OF WATER PLANT SLUDGES Brian A. Dempsey, Assistant Professor James DeWolfe, Graduate Research Assistant Douglas Hamilton, Graduate Research Assistant Yuanjyh Lee, Graduate Research Assistant Roni Liebowitz, Graduate Research Assistant Department of Civil Engineering Herschel A. Elliott, Associate Professor Department of Agricultural Engineering The Pennsylvania State University University Park, Pennsylvania 16802 INTRODUCTION Most municipal and industrial waters are produced by conventional treatment processes, which include the addition of a coagulant during a rapid mixing period, flocculation of solids during a slow mix period, and then separation of the solids by means of sedimentation and filtration processes. Two decades ago most of the sludges produced during conventional water treatment were returned to a watercourse without further treatment. This often resulted in severe detrimental impact to the watercourse, since the sludges contained both the original solids from the watercourse plus new solids generated during treatment and also because the disposal was irregular, with large flows during backwash of the filter or from intermittent cleaning of sedimentation basins. In many cases the sludge was disposed into a smaller watercourse than the source of the water. As a result, the EPA decided that the sludges from municipal and industrial water treatment must be treated in a responsible fashion. Presently, the favorite options for disposal of water plant sludges (WPS) are lagoon storage (usually a temporary solution), landfill (which requires substantial dewatering and may present liability problems, especially for co-disposal), and dumping into sanitary sewers (which often creates an undesirable load on sewage treatment facilities). Land disposal is another option but one that has been used infrequently. State governments usually have primacy regarding the land application of WPS; most state governments are experienced regarding land application of sewage sludge but do not know how to deal with land application of WPS. The lack of regulatory expertise regarding WPS is not surprising. Basic data about the chemical nature of WPS are quite sparse. The literature contains substantial information regarding dewatering of WPS, but almost no data regarding the elemental composition and speciation, the phytotoxicity or microbial toxicity of WPS, and the effects of WPS on the physical and nutrient status of soil. These issues are addressed in this chapter. The goal of this work is to add to the scientific data base regarding WPS so that the reactivity of the sludge (especially, in this case, during land application) can be predicted. More specifically, the following issues are addressed: • What is the impact of WPS on the nutrient status of the soil? • What are the concentrations and reactivities of trace metals in WPS? • What are the other issues that should be used to predict proper loadings of WPS on soils? A COMPARISON OF WATER PLANT SLUDGE AND SEWAGE SLUDGE Sewage sludge contains substantial reactive concentrations of nitrogen and phosphorus, trace elements, and tilth-building organic material. As a result sewage sludge has been used as a soil amendment for millennia. The biggest historical problem has been the spread of pathogens. Since the 44th Purdue Industrial Waste Conference Proceedings, © 1990 Lewis Publishers, Inc., Chelsea, Michigan 48118. Printed in U.S.A. 537 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Tags
Comments
Post a Comment for page 537