Basic Environmental Technology Water Supply Waste Management and

Basic Environmental Technology Water Supply, Waste Management, and Pollution Control SIXTH EDITION CHAPTER 10 Wastewater Treatment and Disposal Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -1 Overview of a centralized wastewater treatment system. Screening, grit removal, and sedimentation (settling) are primary treatment processes. Secondary treatment usually involves biological processes and additional settling. Not all sewage treatment plants require tertiary (or advanced) treatment. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

TABLE 10 -1 Typical NPDES Effluent Limitations Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -2 Typical comminutor installation. (Courtesy of Dresser-Rand Company, Orlean, New York. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -3 Cutaway view of a trickling filter. Trickling filters are sometimes enclosed or covered for odor control or for temperature (and process) control. (Courtesy of FLSmidth, Salt Lake City, Utah. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -4 Recirculation of flow through a trickling filter. The rate of sewage flow applied to the filter is the sum of the influent flow rate and the recirculated flow rate. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -5 (a) Flow diagram of a conventional activated sludge treatment system. (b) View of a typical rectangular aeration tank. (Courtesy of Antiksu/Fotolia. ) (c) A group of circular secondary clarifiers. (Courtesy of Antiksu/Fotolia. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -6 Lab test for the sludge volume index (SVI), which is used to evaluate sludge settling characteristics. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -7 Step aeration modification of the activated sludge process. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -8 Schematic drawing of a typical extended aeration system or "package plant, " shown in (a) plan or top view, and (b) side or section view. (From U. S. Army Corps of Engineers Design Manual EM 1110 -2 -501, Design, Construction, and Operation—Small Wastewater Systems. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -9 Flow diagram for an oxidation ditch. (From Hammer, Sr. , Mark J. ; Hammer, Jr. , Mark J. , Waste and Wastewater Technology, 4 th Ed. , © 2001. Reprinted and Electronically reproduced by permission of Pearson Education, Inc. , Upper Saddle River, New Jersey. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -10 The contact stabilization modification of the activated sludge process. Organic pollutants are absorbed by the microbes in the contact aeration tank and stabilized in the reaeration tank. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -11 Prefabricated circular steel “package plants” are available in diameters up to about 30 m (100 ft). (Courtesy of Siemens Water Technologies. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -12 A group of rotating biological contactors (RBCs), or biodiscs, used for secondary wastewater treatment. The semicircular covers for three RBC units in the foreground have been removed during maintenance work. (Courtesy of Siemens Water Technologies, Waukesha, WI. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -13 Complex biochemical reactions that occur in a wastewater stabilization pond or lagoon. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -14 Auto-backwash rapid filters may be used to polish the effluent in a tertiary or advanced sewage treatment plant: (a) shows the filtration mode, and (b) shows the backwash mode of operation. Three individual filter cells may be constructed in a single prefabricated unit, as shown in (c). (Courtesy of FL Smidth, Salt Lake City, Utah. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -15 Phosphorus can be removed from sewage by chemical precipitation; the chemical, usually alum, can be added at one of four different points in the process. Point 2 is the most common point of application. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -16 Nitrogen can be removed from sewage to prevent eutrophication of lakes. The biological processes of nitrification and denitrification must be carried out after the basic activated sludge process is complete. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -17 Slow rate land treatment. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -18 Rapid infiltration. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -19 Overland flow. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -20 A membrane bioreactor, which combines activated sludge with membrane filtration to accomplish tertiary treatment in a single treatment tank. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -21 Treatment technologies are available to achieve any desired level of water quality. (Courtesy of EPA 2012 Guidelines for Reuse. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -22 Flowchart for planned IPR options. (Courtesy of EPA 2012 Guidelines for Reuse. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -23 A conventional OWTS. Contaminants are removed from the septic tank effluent as it percolates through soil layers. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -24 Types of soil structure and percolation rates. (Courtesy of U. S. Department of Agriculture. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -25 A perc test can be conducted using a batter board and a meterstick or yardstick. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -26 (a) Perspective view of an on-site subsurface sewage disposal system that utilizes a septic tank and leaching or absorption field. (b) As the effluent enters the drainfield, most of it percolates through the gravel, in which pockets of oxygen allow aerobic bacteria to live and pathogenic bacteria perish. Phosphorus and nitrogen are metabolized by the vegetation covering the drainfield, and a portion of the moisture is returned to the atmosphere through evapotranspiration. (From J. von. Meier, Groundwater Contamination and Septic System Failure, 1996. Used with permission. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -26 (continued) (a) Perspective view of an on-site subsurface sewage disposal system that utilizes a septic tank and leaching or absorption field. (b) As the effluent enters the drainfield, most of it percolates through the gravel, in which pockets of oxygen allow aerobic bacteria to live and pathogenic bacteria perish. Phosphorus and nitrogen are metabolized by the vegetation covering the drainfield, and a portion of the moisture is returned to the atmosphere through evapotranspiration. (From J. von. Meier, Groundwater Contamination and Septic System Failure, 1996. Used with permission. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -27 Side view in a dual-compartment septic tank. (From Pipeline, Fall 2004, National Small Flows Clearinghouse, West Virginia University. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -28 Plan view of a typical residential on-site subsurface sewage disposal system. (From Environmental Engineering and Sanitation, 4 th ed. , J. Salvato. Copyright © 1992 John Wiley & Sons. This material is used by permission of John Wiley & Sons, Inc. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -29 Cross section through an absorption field trench. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -30 Typical absorption or leaching field area requirements for private residencies; total required area depends on the perc rate and on the number of bedrooms in the home. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -31 Cross section of a typical seepage pit for on-site disposal of wastewater. A seepage pit is preceded by a septic tank. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -32 A mound system for on-site sewage disposal. (From Pipeline, Fall 2002, National Small Flow Clearinghouse, West Virginia University. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -33 An evapotranspiration system for on-site sewage disposal. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -34 Cross section through a typical buried sand filter for on-site sewage disposal. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -35 Section view of a typical dosing chamber and siphon device. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -36 Side view of a typical prefabricated aerobic treatment unit. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -37 A stock-feed tablet chlorinator. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -38 Flow diagram for a closed wastewater recycle–reuse system. (From U. S. Army Corps of Engineers Design Manual EM 1110 -2 -501, Design, Construction, and Operation-Small Wastewater Systems. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -39 Alternative pathways for sewage sludge treatment and disposal. Sludge disposal in the ocean is no longer allowed in the United States. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -40 The dissolved-air sludge flotation process can be used to thicken sewage sludge. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -41 Schematic diagram of the two-stage anaerobic sludge digestion process. Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -42 A section of a sludge drying bed. (Reprinted with permission from Operation of Wastewater Treatment Plant, 2 nd ed. , MOP No. 11, Copyright © 1976, Water Environment Federation, Alexandria, VA. www. wef. org. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -43 a Schematic diagram of a multiple-hearth sludge incinerator. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved

FIGURE 10 -43 b Cross section of a fluid bed furnace. (Courtesy of U. S. Environmental Protection Agency. ) Basic Environmental Technology, Sixth Edition Jerry A. Nathanson | Richard A. Schneider Copyright © 2015 by Pearson Education, Inc. All Rights Reserved