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The Effect of Aluminum Sulfate Addition on Production of Volatile Organic Sulfur Compounds from Anaerobically Digested Biosolids
Yen-Chih Chen, Gregory Adams, Zeynep Erdal, Robert H. Forbes, Jr., J. Ronald Hargreaves, Matthew J. Higgins, Sudhir N. Murthy, John T. Novak, Jay Witherspoon, William E. Toffey
Abstract

Rangeland Restoration Using Biosolids Land Application
Michael J. McFarland, Issaak R. Vasquez, MaiAnh Vutran, Mark Schmitz, Robert B. Brobst, Linden Greenhalgh
Abstract

Correlating Fecal Coliform Measurements and Odors in Biosolids Cake to Digester Performance Parameters
William E. Toffey, Matthew Higgins
Abstract

Biosolids Process Enhancements for Fecal Coliform Reduction
Todd O. Williams, Rhonda L. Bowen
Abstract

Full Scale and Laboratory Scale Results from the Trial of MicroSludge at the Joint Water Pollution Control Plant at Los Angeles County
Rob Stephenson, Scott Laliberte, Preston Hoy, Diana Britch
Abstract

Impacts of the MicroSludgeTM Process on Odor Causing Compounds in Anaerobically Digested Biosolids
John T. Novak, Chul Park, Matthew J. Higgins, Yen-Chih Chen, Robert Morton, Dan Gary, Robert Forbes, Zeynep Erdal
Abstract

Concentrated Animal Feeding Operation (CAFO) Regulation at Federal and Select State Levels
Lynne H. Moss
Abstract

Strategies to Reduce Nitrogen and Phosphorus Losses from Land Applied Animal Manure
Shalamar D. Armstrong, Douglas R. Smith, Phillip R. Owens
Abstract

Switching from Incineration of the Heat Treated Sludge to Incineration of the Untreated Sludge at the Region of Peel Lakeview WWTP
William Fernandes, Ky Dangtran, Jim Welp
Abstract

Oxidation of Excess Organic Sludge from a Moving-bed Biofilm Process
Joseph D. Rouse, Olga Burica, Marjeta Strazar, Meta Levstek
Abstract

The Effect of Aluminum Sulfate Addition on Production of Volatile Organic Sulfur Compounds from Anaerobically Digested Biosolids

Yen-Chih Chen^1*,  Gregory Adams²,  Zeynep Erdal³,  Robert H. Forbes, Jr.³,  J. Ronald Hargreaves²,  Matthew J. Higgins¹,  Sudhir N. Murthy⁴,  John T. Novak⁵,  Jay Witherspoon³,  William E. Toffey⁶

¹ Department of Civil and Environmental Engineering, Bucknell University.
² Los Angeles County Sanitation Districts.
³ CH2MHill.
⁴ DC Water and Sewer Authority.
⁵ Department of Civil and Environmental Engineering, Virginia Tech.
⁶ Philadelphia Water Department.
^*To whom correspondence should be addressed.

Abstract
The formation of volatile organic sulfur compounds (VOSCs), a group of key biosolids odorants, has been linked to microbial degradation of residual bioavailable proteins.  In this research, aluminum sulfate (alum) was used to reduce biobavailability of soluble proteins in biosolids, thus prevent them from biodegradation.  Both laboratory trials and field trials were performed using alum dosages of 0, 0.5, 1, 2, and 4% (w/w, aluminum/dry solids).  The laboratory trial results indicated that alum can effectively reduce biosolids odor, and up to 100% removal of total VOSCs (TVOSCs) at 4% alum.  In a field trial, up to 55% TVOSCs reduction was observed at 4% alum.  The lower dosages of alum were also able to reduce polymer demand for conditioning which could offset alum costs.  Overall, this research showed the potential of using alum for biosolids odor control, although additional research is needed to understand the effect of alum addition.

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Michael J. McFarland^1*, Issaak R. Vasquez¹, MaiAnh Vutran¹, Mark Schmitz²,
Robert B. Brobst³ and Linden Greenhalgh⁴

¹Department of Civil and Environmental Engineering, Utah State University, Logan, Utah, USA.
²Utah Department of Environmental Quality, Salt Lake City, Utah, USA.
³US Environmental Protection Agency Region 8, Denver, Colorado, USA.
⁴ Utah State University Cooperative Extension, Tooele County, Utah, USA.
^*To whom correspondence should be addressed.

Abstract
Land application of aerobically digested biosolids, anaerobically digested biosolids and beef cattle manure as an approach to restore disturbed rangelands was evaluated.  While control plots yielded, on average, 84.1 lbs/acre of forage dry matter, dry forage yield on rangeland plots receiving aerobically digested biosolids, anaerobically digested biosolids and beef cattle manure ranged from 129.0 to 664.1 lbs/acre.  Field tests indicated an average moisture infiltration rate of 7.07 cm/hr for control plots compared to a maximum of 7.14, 9.98 and 9.56 cm/hr in plots receiving aerobically digested, anaerobically digested and beef cattle manure, respectively.  The increase in forage yield and moisture infiltration underscored the value of biosolids land application in rangeland restoration activities.

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William E. Toffey^1*, Matthew Higgins²

¹Philadelphia Water Department, 1101 Market Street, Suite 5. Philadelphia, PA 19107.
²Bucknell University
^*To whom correspondence should be addressed.

Abstract
The Southwest Water Pollution Control Plant (SW WPCP) of the Philadelphia Water Department is the one facility used by the Water Environment Research Foundation (WERF) in both research studies linking performance of single-stage mesophilic anaerobic digesters with characteristics of biosolids odor generation and of fecal coliform reactivation and regrowth. This paper reports on the statistical treatment of the operational records of the digesters and centrifuges at its SW WPCP and the adjoining centralized dewatering facility, the Biosolids Recycling Center (BRC), against the corresponding fecal coliform and odor databases.  This review confirms the WERF study report conclusions:  1) no correlation is seen between variation in volatile solids destruction and the variation in odorant intensity of the biosolids or the variation in geometric mean of fecal coliform; 2) no correlation is seen between the variation in time-temperature performance over the study period and variations in odor intensity and fecal coliform density.

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Todd O. Williams^1* and Rhonda L. Bowen²

¹CH2M HILL, Inc.10800 Midlothian Turnpike Suite 129Richmond, VA  23235
²Hampton Roads Sanitation District, Virginia Beach, Virginia
^*To whom correspondence should be addressed.


Abstract
Approximately 60 percent of wastewater utilities across the nation land apply biosolids for agricultural use. Most utilities, including HRSD, have traditionally used the time and temperature method to demonstrate compliance with state and federal regulations. Recent research suggests the possibility that some dewatering processes following digestion may exhibit re-activation and/or re-growth of fecal coliform bacteria.  A series of tests were initiated to measure fecal coliform levels in biosolids cake generated at the Atlantic Treatment Plant. Initial test results indicated an increase in fecal coliform bacteria concentrations after dewatering. HRSD conducted additional tests in June through December 2006 to determine methods of preventing the fecal coliform re-activation/re-growth phenomenon. This paper presents the finding of this testing and reports on the methodologies used, the options tested, and the efficiency of a low lime dosing process in meeting the operating objectives. 

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Rob Stephenson^*, Scott Laliberte, Preston Hoy, Diana Britch

¹Paradigm Environmental Technologies Inc., 200 – 600 West 6th Avenue, Vancouver, BC, Canada.
^*To whom correspondence should be addressed.


Abstract
MicroSludge® is a patented chemical and pressure pre-treatment process that uses chemical pre-treatment to weaken cell membranes and then a high-pressure homogenizer, or “cell disrupter”, to provide an enormous and sudden pressure change to burst the cells in WAS.  By increasing the liquefied proportion of WAS by orders of magnitude, a greater proportion of WAS may be converted to biogas and at a faster rate. A full-scale MicroSludge unit was commissioned at the Los Angeles County Sanitation Districts’ (LACSD’s) Joint Water Pollution Control Plant (JWPCP) in October 2005 for 12 months of testing. The system was operated for 24 hours each day to process approximately 192 m3/day (50,000 GPD) of thickened WAS at an average concentration of 5.4% total solids (TS).  The processed WAS was co-digested with primary sludge (PS) in a 75:25 by volume (approximately 68:32 by mass) PS:WAS mix at a nominal HRT of 19 days.

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John T. Novak^1*, Chul Park¹, Matthew J. Higgins², Yen-Chih Chen², Robert Morton³, Dan Gary³, Robert Forbes⁴, Zeynep Erdal⁴

¹ Virginia Polytechnic Institute and State University.
² Bucknell University.
³Los Angeles County Sanitation Districts.
⁴CH2MHILL, Inc.
^*To whom correspondence should be addressed.

Abstract
The MicroSludgeTM process is a patented process that liquefies waste activated sludge (WAS) to improve the rate and extent of its degradation by anaerobic digestion. The MicroSludge process was operated full-scale at the Los Angeles County Sanitation District’s Joint Water pollution Control Plant from October 2005 until August 2006 to evaluate the performance of this technology for enhancing anaerobic digestion. Biosoilds samples from the anaerobic digester receiving MicroSludge treated WAS were compared to samples from a control digester to determine the effect of the MicroSludge process on odor generation from dewatered sludge cakes. It was found that the MicroSludge process reduced total volatile organic sulfur compounds (TVOSC) by about 50% for most sludges tested, even though the fraction of WAS was only 25% of the digester feed. The mechanism for the reduction is not clear since the additional volatile solids reduction was in the range of 3 to 6%.  

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Lynne H. Moss^1*

¹BCEE, CDM, Inc.,
^*To whom corresondence should be addressed.

Abstract
Livestock operations across the United States are universally experiencing regulatory change.  The scope and focus of those changes vary, however, depending upon different driving forces in individual states and locales.  Livestock operations are a key market for soybeans and, to better understand the potential impacts of environmental regulations on livestock operations, the United Soybean Board (USB) commissioned an audit of these requirements.  The audit explored both existing and proposed regulations on a federal level and on a state-by-state basis, with a special emphasis on key states characterized by strong soybean and/or livestock production. This document highlights the results of that audit.

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Shalamar D. Armstrong^1,2 , Douglas R. Smith^2*, and Phillip R. Owens¹

¹ Department of Agronomy, Purdue University.
²USDA-ARS, National Soil Erosion Research Laboratory.
^*To whom correspondence should be addressed.

Abstract
Continued land application of animal manure to agriculture fields often results in elevated soil N and P concentrations that may exceed crop requirements and may be lost to surface water bodies.  Several strategies can be used by landowners and animal producers to minimize losses of N and P from agricultural fields, including: dietary modification; manure amendments; manure application method and soil preparation; buffer strips; and using the P index to determine the manure application rates and risks.  Researchers have demonstrated that both diet modifications and aluminum amendments can reduce soluble P in manure and runoff by 60 to 95%, while manure injection reduced runoff total P by 92 %.  The employment of these and other strategies by responsible landowners is critical in reducing the vulnerability of N and P to losses via runoff following animal manure application.

William Fernandes^1*, Ky Dangtran², Jim Welp³

¹Region of Peel WWTP, Ontario.
²Degremont Technologies Infilco.
³Black & Veatch.
^*To whom correspondence should be addressed.

Abstract
The Lakeview wastewater treatment plant (WWTP) in Mississauga, Ontario, is owned by the Region of Peel and is operated by the Ontario Clean Water Agency (OCWA). The plant has been equipped with fluid bed incineration (FBI) systems as its disposal option for almost thirty years. Due to the high maintenance and the odor generated by Zimpro, in 2003 the Region of Peel decided to eliminate the heat-treated system and to replace the three existing CWB fluid beds by four hot-windbox (HWB) fluid beds, each dispose of 110 US tons of dry sludge per day. The new system is equipped with external shell and tube heat exchanger for preheating the combustion air to 1230oF and a multiple venturi scrubber as air pollution control device. The system satisfied the design emission requirements by a wide margin upon performance testing. The paper discusses the transition period during the replacement of the Zimpro system.

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Joseph D. Rouse^1*, Olga Burica², Marjeta Strazar², Meta Levstek²

¹ Kuraray Co., Ltd., Japan
² Domzale-Kamnik Wastewater Treatment Plant, Slovenia
^* To whom correspondence should be addressed.


Abstract
Biological oxidation of organic sludge yielded by a moving-bed biofilm process utilizing PVA-gel beads as the biocarrier was investigated.  In contrast to previous studies with industrial wastewaters free of suspended solids (SS), in this pilot test treatment of a municipal wastewater was considered where the influent SS could have a significant impact on sludge decay.  Under steady-state conditions without wasting any sludge from the system, excess sludge was maintained in an aerobic oxidation process at a level of 8 g/L with a hydraulic retention time of 8 h.  A mass-balance across the system indicated biomass yield and decay rates suitable for effective elimination of organic sludge.  Though further observation is warranted to evaluate performance over long-term operation, results here suggest that excess organic sludge of a municipal wastewater treatment plant can be greatly reduced in quantity by using a PVA-gel biofilm process coupled with endogenous decay of excess biomass.

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