Download or read book Characterization and Stabilization of Arsenic in Water Treatment Residuals written by Hun Young Wee and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The characterization of water treatment residuals containing arsenic was investigated in the first study. Arsenic desorption and leachability from the residuals were the focus of this study. Arsenic leaching from water treatment residuals was found to be underestimated by the toxicity characteristic leaching test (TCLP) due to the pH of the leachates being favorable for As(V) adsorption. Competitive desorption of arsenic with phosphate was significant because phosphate tends to compete with As(V) on the surface of the metal hydroxide for adsorption sites. However, arsenic desorption by the competition of sulfate and chloride was found to be negligible. The pH in the leachate was a critical variable in controlling arsenic stability in the residuals. The release of arsenic from the residuals was elevated at low and high pH due to the increase dissolution of the adsorbents such as Fe and Al hydroxides. In the second phase of the study, the stabilization techniques for arsenic contained residuals and were examined to develop methods to suitably stabilize arsenic to eliminate and/or minimize leaching. A decrease of arsenic leaching was achieved by the addition of lime to the residuals and believed to be due to the formation of less soluble and stable calcium-arsenic compounds. However, it is suggested that the ordinary Portland cement (OPC) should be added with the lime for the long term stabilization because lime can be slowly consumed when directly exposed to atmospheric CO2. The solidification and stabilization (S/S) technique with lime and OPC was shown to be successfully applied by the immobilization of a wide variety of arsenic tainted water treatment residuals.

Download or read book Assessment of Arsenic Treatment Residuals written by T. Kramer and published by International Water Assn. This book was released on 2009 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives of this research were to (1) conduc

Download or read book Removal of Arsenic in Drinking Water written by and published by DIANE Publishing. This book was released on 2005 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book In situ Stabilization of Arsenic in Florida Soils Amended with Water Treatment Residuals written by Christopher Darrell Amy and published by . This book was released on 2008 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Arsenic Water Technology Partnership Final Technical Report written by and published by . This book was released on 2010 with total page 371 pages. Available in PDF, EPUB and Kindle. Book excerpt: Congress created the Arsenic Water Technology Partnership (AWTP) in 2002 to develop and provide solutions for the cost-effective removal of arsenic from drinking water. The AWTP was funded by four congressional appropriations (FY03-FY06) to evaluate and develop new technologies that could significantly reduce compliance costs associated with the new 0.010 mg/L maximum contaminant level (MCL) for arsenic in drinking water. Initially focused on arsenic research, in FY06 the AWTP was expanded to include desalination research upon recognition that the research challenges were similar. The funding for the research and subsequent transfer of technology was made available by Congress through the Department of Energy (DOE). The AWTP was a collaborative effort between DOE's Sandia National Laboratories (Sandia), Water Research Foundation (WaterRF, formerly Awwa Research Foundation) and WERC: A Consortium for Environmental Education and Technology Development based at New Mexico State University (WERC). Key features of the AWTP included technology development, technology implementation/testing and technology transfer. Each of the partners evaluated and oversaw development of new arsenic and desalination treatment technologies, and the technology transfer program ensured that successful technologies were transferred to the water supply community. Through the use of an arsenic treatment cost model, training sessions and a web site, information on arsenic removal and desalination technologies was transferred to stakeholders. KEY ACCOMPLISHMENTS The AWTP partnership funded research on, and deployment and testing of, innovative arsenic and desalination removal technologies; education for small and large water system operators; and development of a comprehensive web-based tool for arsenic treatment technology selection using site-specific data. As water becomes scarcer, and potable water supplies become increasingly vulnerable to contamination, the development of affordable water treatment systems is critical. Choosing the best available treatment system can be difficult. The AWTP has developed and evaluated improved arsenic and desalination treatment systems and provided that information to water utilities and stakeholders. Key technology advancements achieved by the partnership include: ARSENIC Development and full-scale implementation (San Antonio, NM) of an in-situ treatment process that is producing drinking water without the generation of any residuals that require disposal. The way is now paved for in-situ treatment to be used throughout the U.S. Detailed information on how to evaluate and prevent unintended consequences of bringing an arsenic treatment technology online prior to implementation, including: -potential for increased distribution system corrosion -potential for treatment systems to release arsenic into drinking water due to unintended pH variation Methods and options on the most appropriate ways to classify, stabilize and dispose of potentially hazardous arsenic-containing water treatment residuals A much improved understanding of water quality characteristics that impact specific treatment technologies allowing for site-specific selection of a best-available-technology Demonstrated at pilot scale that use of ultra-light filter media in a coagulation-filtration process can significantly reduce required backwash water volume and achieve 99 percent feedwater recovery while effectively removing arsenic Development of a polymeric ligand exchanger that selectively and effectively removes the oxidized form of arsenic under typical groundwater conditions, which is best utilized for treating water with high sulfate and relatively low alkalinity Development of iron-granular activated carbon (GAC) and titanium-GAC composite adsorbents for arsenic removal, which can simultaneously remove contaminants that adsorb onto activated carbon, e.g., neutral organic chemicals, radionuclides, and taste-and-odor compounds DESALINATION Development of a comprehensive and detailed set of guidelines for utilities wanting to evaluate and bring a desalination treatment process online Improved understanding of membrane fouling in seawater desalination, and evaluation of a pretreatment method to minimize fouling Improved understanding of mechanisms underlying VSEP, a membrane-based inland brackish desalination process that may enhance recovery by up to 25% Demonstrated a hybrid reverse osmosis-forward osmosis process which can enhance seawater desalination through dilution with treated wastewater.

Download or read book Arsenic Removal from Drinking Water by Coagulation filtration and Lime Softening Plants written by Keith A. Fields and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents water treatment plant information as well as results of sampling & analysis at two coagulation/filtration plants & one lime softening plant. The objective of sampling & analysis was to evaluate the effectiveness of the water treatment plants to consistently remove arsenic (As) from source water. Additionally, data were collected in this study to evaluate the characteristics of the residuals produced by the treatment processes. The study was divided into 3 phases: source water sampling, preliminary sampling, & long-term evaluation. Includes 3 appendices, 20 figures, & 26 tables.

Download or read book Arsenic Treatability Options and Evaluation of Residuals Management Issues written by Gary L. Amy and published by American Water Works Association. This book was released on 2000 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stabilization of Arsenic Wastes written by Max Taylor and published by DIANE Publishing. This book was released on 1994 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides experimental research: a review of stabilization, arsenic chemistry, & treatment; experimental methods & procedures; & a description of the experimental design & results. Research was conducted to understand & develop this promising stabilization process. Contains 90 tables & figures.

Download or read book Arsenic Treatment Technologies for Soil Waste and Water written by and published by DIANE Publishing. This book was released on 2002 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Disposal of Waste Resulting from Arsenic Removal Processes written by D. Cornwell and published by IWA Publishing. This book was released on 2004-01-01 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are a number of treatment techniques that can effectively remove arsenic from drinking water. It is essential for utilities that are in the process of selecting an arsenic removal treatment technology to also identify the types of residuals that would be generated, their expected arsenic concentrations, and pre-treatment strategies that would be required prior to final disposal. This document provides utility guidelines for disposal of residuals containing elevated concentrations of arsenic.Originally published by AwwaRF for its subscribers in 2003 This publication can be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below

Download or read book Arsenic Adsorption and Desorption by Drinking Water Treatment Residuals written by Vandana Vandanapu and published by . This book was released on 2005 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effectiveness of Al and Fe based Drinking water Treatment Residuals in Remediating Soil Arsenic written by Rachana Nagar and published by . This book was released on 2008 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pelletized Drinking Water Treatment Residuals for the Removal of Arsenic and Phosphate from Water written by Roberta Hofman-Caris and published by . This book was released on 2018 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Long Term Stabilization of Arsenic Bearing Solid Residuals Under Landfill Conditions written by Madhumitha Raghav and published by . This book was released on 2013 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: The maximum contaminant level (MCL) for arsenic in drinking water was reduced to 10 parts per billion in 2006 by the USEPA. As a result, approximately 10,000 tons of arsenic-bearing residuals (ABSRs) are estimated to be generated every year from water treatment processes. It has also been established that the standard Toxicity Characteristic Leaching Procedure (TCLP), underestimates arsenic leaching from ABSRs, particularly under mature, mixed solid waste landfill conditions. This makes it critical to investigate stabilization technologies that would ensure long-term stability of arsenic residuals after disposal. Arsenic is ubiquitously associated with iron oxides in natural environments as well as water treatment residuals. Hence, knowledge of iron oxide transformations under landfill conditions is critical to understanding the fate and mobility of the associated arsenic. In this work, the effect of high local Fe(II) concentrations on ferrihydrite transformation pathways was studied. Magnetite was the sole transformation product in the presence of high local Fe(II) concentrations. In the absence of high Fe(II) concentrations, goethite was the major transformation product along with minor quantities of magnetite. These results have implications for arsenic mobility from ABSRs since goethite and magnetite have different arsenic sorption capacities and mechanisms. Two technologies were investigated for the stabilization of ABSRs - Arsenic Crystallization Technology (ACT) and Microencapsulation. The strategy for ACT was to convert ABSRs into minerals with a high arsenic capacity and long-term stability under landfill conditions. Scorodite, arsenate hydroxyapatites, ferrous arsenate, arsenated schwertmannite, tooeleite and silica-amended tooeleite, were synthesized and evaluated for their potential to serve as arsenic sinks using TCLP and a simulated landfill leachate test. Ferrous arsenate type solids and arsenated schwertmannite showed most promise in terms of low arsenic leachability and favorable synthesis conditions. Microencapsulation involved coating arsenic-loaded ferrihydrite with a mineral having high stability under landfill conditions. Based on results from a previous study, vivianite was investigated as a potential encapsulant for ABSRs. A modified version of the TCLP was used to evaluate the effectiveness of microencapsulation. Although vivianite did not prove to be a promising encapsulant, our efforts offer useful insights for the development of a successful microencapsulation technology for arsenic stabilization.

Download or read book Arsenic Mobility in Water Treatment Sludge and Its Stabilization Mechanisms written by Chuanyong Jing and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Backwash Residuals and Media Characterization at Desert Sands Arsenic Removal Facility written by Zachary Doubrava Hendren and published by . This book was released on 2005 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Arsenic Treatment Technologies for Soil Waste and Water written by and published by DIANE Publishing. This book was released on 2002 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: