Anaerobic Digester Hydrogen Sulfide Removal

Manatee County, FL Southwest Water Reclamation Facility

This paper presents results of a full-scale trial initiated in May 2006 by the Manatee County Southwest Water Reclamation Facility and examines the impacts of peroxide regeneration of spent iron salts on the removal of hydrogen sulfide (H2S) from anaerobic digesters. Dissolved sulfide levels in the primary digester dropped throughout the course of the trial biogas H2S concentrations were reduced by 90% on average. Additional positive changes were noted in the volume and quality of biogas produced, and in finished biosolids quality.

Bio-Solids Process Enhancements Resulting From the Use of Hydrogen Peroxide for Hydrogen Sulfide Odor Control—The San Antonio Experience

This paper presents results of a trial initiated in February 2004 by the San Antonio Water System to quantify the impacts of hydrogen peroxide injection prior to dissolved air flotation thickening of wastewater sludges. The use of hydrogen peroxide has performed beyond expectations since its introduction for odor control of the Leon Creek WRC sludge transferred to the Dos Rios facility. It has also resulted in significant increases in digester gas production, and some improvements in sludge dewaterability.

The Use of Peroxide Generated Iron-Sulfide Control (PRI-SC)® for Long Duration Collection System Control

Regional Municipality of York

Corrosion of collection system piping and components has become a big problem for many municipalities balancing growth and the maximum service life for existing collection system infrastructure. This paper presents the results of a trial initiated in August 2005 by The Regional Municipality of York (York Region) to quantify the impacts of PRI-SC® for control of hydrogen sulfide (H2S) in a long retention time section of the collection system. PRI-SC® technology enabled significant reductions of H2S over a 12 hour retention time section of the collection system.

Peroxide Regenerated Iron-Sulfide Control (PRI-SC)®

Integrating Collection System Sulfide Control with Enhanced Primary Clarification by Adding Iron Salts and Hydrogen Peroxide

This paper presents the results of a field trial conducted at the Orange County Sanitation Districts using PRI-SC®, to moderate the shortcomings of using iron salts to both control hydrogen sulfide within collection systems and to enhance primary clarification at treatment plants. The study involved three major interceptors and the results show the PRI-SC® technology met the control objectives at a significantly lower cost than other commonly used chemical technologies.

Reprinted with permission from Proceedings of WEFTEC®.03, the 76th Annual Water Environment Federation Technical Exhibition and Conference, Los Angeles, October 11 - 15, 2003.

Copyright © 2003 Water Environment Federation, Alexandria, Virginia. This paper may be downloaded for personal uses only. Any other use requires prior permission of the Water Environment Federation.

Oxidative Regeneration of Iron for Treatment Plant Purposes

In a previous paper, we reported improved sulfide control efficiencies in the collection system using PRI-SC® to control hydrogen sulfide emissions within the Orange County Sanitation Districts. This paper discusses benefits of regenerating iron a second time to benefit CEPT using hydrogen peroxide and bleach at OCSD Plant No. 2. The results show that maximizing the overall cost performance of all relevant chemical additions at the plant requires that the influent sulfide be removed and the ferrous portion of the influent iron (from PRI-SC®) be oxidized to ferric iron. Ultimately, this approach represents a 40% savings over adding additional FeCl3.

Reprinted with permission from Proceedings of WEFTEC®.05, the 78th Annual Water Environment Federation Technical Exhibition and Conference, Washington, DC, October 30 - Nov. 2, 2005. Copyright © 2005 Water Environment Federation, Alexandria, Virginia. This paper may be downloaded for personal uses only. Any other use requires prior permission of the Water Environment Federation.

Hydrogen Peroxide for Regeneration of Ferrous Chloride, an Innovative Approach to Hydrogen Sulfide Control

Case Study: Fargo, North Dakota

Increased odor complaints prompted an evaluation of the odor conditions present in the sanitary sewer system in Fargo, North Dakota. Due to an existing FeCl2 injection program, iron regeneration and improved odor control were realized through the innovative use of hydrogen peroxide. Seeing improved sulfide treatment, reduced FeCl2 injection rates, and economic benefits via a demonstration program, the City of Fargo elected to incorporate the technology as part of their upcoming collection system improvements.

Reprinted with permission from Proceedings of WEFTEC®.09, the 82nd Annual Water Environment Federation Technical Exhibition and Conference, Orlando, FL, October 10 - 14, 2009. Copyright © 2009 Water Environment Federation, Alexandria, Virginia. This paper may be downloaded for personal uses only. Any other use requires prior permission of the Water Environment Federation.