Adsorptive Removal Of Arsenic And Chromium From Two California Groundwater Sources Using Rapid Small Scale Column Tests PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Adsorptive Removal Of Arsenic And Chromium From Two California Groundwater Sources Using Rapid Small Scale Column Tests PDF full book. Access full book title Adsorptive Removal Of Arsenic And Chromium From Two California Groundwater Sources Using Rapid Small Scale Column Tests.
Author | : Andrew Ryan Schmalenbach |
Publisher | : |
Total Pages | : |
Release | : 2014 |
Genre | : |
ISBN | : 9781321609844 |
Download Adsorptive Removal of Arsenic and Chromium from Two California Groundwater Sources Using Rapid Small Scale Column Tests Book in PDF, ePub and Kindle
At the federal level, the United States Environmental Protection Agency (US EPA) started enforcing a maximum contaminant level (MCL) of 10 [mu]g/L arsenic in public water systems in 2006, down from 50 [mu]g/L. As of July 1st, 2014 the state of California started enforcing a 10 [mu]g/L MCL for hexavalent chromium, formerly 50 [mu]g/L total chromium. These changes have sparked increased demand for cost effective treatment technologies for these contaminants, which has in turn driven research in the field. Iron oxide adsorbents are an established treatment method for arsenic removal, but have not been proven effective in treating chromium. Despite extensive documentation on the effectiveness of treating arsenic with iron oxide adsorbents, variations in source water qualities result in bed lifespans that must be estimated on a case-by-case basis. Scaled down adsorption tests that can be completed in 2-4 weeks, known as rapid small-scale column tests (RSSCTs), were used to conduct two studies. In one study, an established arsenic adsorbent (E-33) was subjected via RSSCT to a particular arsenic contaminated groundwater to quantify its removal capacity for that water source. In another study, a new and largely untested iron oxide adsorbent (E-33 HC) was tested in an RSSCT with chromium contaminated groundwater to measure its effectiveness for chromium removal. E-33 treated approximately 15,000 bed volumes of source water in the first study. The second study indicated that E-33 HC was not effective in removing chromium from the source water tested.
Author | : Jacqueline Pui Yun Chin |
Publisher | : |
Total Pages | : |
Release | : 2012 |
Genre | : |
ISBN | : 9781267967800 |
Download Rapid Small-scale Column Tests of Metal-based Adsorbent Media for Arsenic Removal from Groundwater Sources in California Book in PDF, ePub and Kindle
The United States Environmental Protection Agency (EPA) lowered the maximum contaminant level (MCL) for arsenic in drinking water in 2001, effective January 2006, from 50 micrograms per liter ([mu]g/L) to 10 [mu]g/L resulting in increased development of arsenic removal technologies. Water systems throughout the U.S., in particular small water systems, have found it difficult to meet this MCL with the resources they have. The EPA has created a series of documents to assist these systems in choosing a cost-effective water treatment technology with recommendations for adsorption technology. When deciding on adsorption technology, there is a plethora of adsorbent media to select from, such that costs will vary drastically from one media to the other. In this work, four metal-based iron hydroxides (granular ferric hydroxide, Bayoxide E33 goethite, Metsorb G titanium dioxide, and NXT-2 lanthanum hydroxide) were compared using rapid small scale column tests (RSSCT). The RSSCTs were conducted with three groundwater sources from select communities in the Central Valley region of California to determine impacts on arsenic adsorption capacity. The breakthrough curves from the RSSCTs were used to approximate the cost of adsorption treatment with respect to replacing adsorbent media. The results of this work suggest Bayoxide E33 may be the cost effective treatment option for the small water systems that were evaluated. Interferences in effective arsenic removal include phosphorus, silica, high arsenic concentrations, low alkalinity, and high pH. The RSSCTs completed for Manteca groundwater supplies were packed with Bayoxide E33 and validated the dependence of arsenic adsorption capacity on pH, phosphorus, arsenic, and alkalinity.
Author | : |
Publisher | : |
Total Pages | : 50 |
Release | : 2008 |
Genre | : Water |
ISBN | : |
Download Assessing Arsenic Removal by Metal (Hydr)Oxide by Adsorptive Media Using Rapid Small Scale Column Tests Book in PDF, ePub and Kindle
The lowering of the maximum contaminant level for arsenic in drinking water from 50 to 10 micrograms per liter has posed significant technical and financial challenges to water treatment facilities throughout the United States. To assist small water systems (less than 10,000 customers) in meeting the new standard, EPA announced in October 2001 an initiative, the Arsenic Rule Implementation Research Program, to conduct a series of full-scale, on-site demonstrations of arsenic removal technologies, process modifications, and engineering approaches applicable to small systems. Of the 40 project sites under the Round 1 and Round 2 demonstration program, 23 selected adsorptive media technology because of its ease of operation.
Author | : Marek Bryjak |
Publisher | : CRC Press |
Total Pages | : 488 |
Release | : 2016-02-17 |
Genre | : Science |
ISBN | : 1315682605 |
Download Innovative Materials and Methods for Water Treatment Book in PDF, ePub and Kindle
Due to increasing demand for potable and irrigation water, water suppliers have to use alternative resources. They either have to regenerate wastewater or deal with contaminated surface water. This book brings together the experiences of various experts in preparing of innovative materials that are selective for arsenic and chromium removal, and in
Author | : Valentine Uwamariya |
Publisher | : CRC Press |
Total Pages | : 0 |
Release | : 2014-03-19 |
Genre | : Science |
ISBN | : 9781138020641 |
Download Adsorptive Removal of Heavy Metals from Groundwater by Iron Oxide Based Adsorbents Book in PDF, ePub and Kindle
In general, groundwater is a preferred source of drinking water because of its convenient availability and its constant and good quality. However this source is vulnerable to contamination by several substances. Acceptable quality limits relative to micropollutant contents in drinking water are becoming increasingly lower and efficient elimination treatment processes are being implemented in order to meet these requirements. Metals contaminants at low concentration are difficult to remove from water. Chemical precipitation and other methods become inefficient when contaminants are present in trace concentrations and the process of adsorption is one of the few alternatives available for such situations. This book describes the adsorption method in the removal of selected heavy metals present as cations (Cd2+, Cu2+ and Pb2+) or oxyanions (Cr(VI) and As(V)) using iron oxide coated sand (IOCS) and granular ferric hydroxide (GFH). The effects of pH, natural organic matter (fulvic acid (FA)) and interfering ions (PO43-, Ca2+) on the adsorption efficiency were also assessed. The sorption reactions that take place at the surface of the adsorbent were also described through the surface complexation modelling for Cd2+, Cu2+ and Pb2+ adsorption. Batch adsorption tests and rapid small scale column tests (RSST) were used as laboratory methods.
Author | : Alicia Renee Aragon |
Publisher | : |
Total Pages | : 288 |
Release | : 2004 |
Genre | : Metallic oxides |
ISBN | : |
Download Development of a Rapid Small-scale Column Testing Procedure for the Evaluation of Arsenic Adsorption Media Book in PDF, ePub and Kindle
Author | : Omar Al-Attas |
Publisher | : |
Total Pages | : |
Release | : 2012 |
Genre | : Adsorption |
ISBN | : |
Download Competitive Adsorption of Iron and Natural Organic Matter in Groundwater Using Granular Activated Carbon Book in PDF, ePub and Kindle
The treatment of potable water in Vars, ON is accomplished by filtering the colored, iron-laden groundwater through granular activated carbon (GAC) filters. When first installed, these filters unexpectedly experienced chromatographic displacements of iron into the produced water which resulted in orange-brown water at consumers' taps. The treatment plant was later modified by adding potassium permanganate oxidation and a greensand filter prior to the GAC adsorption columns. Consequently, iron was almost completely removed and no longer caused operational problems. The main objective of this dissertation is to study the interactions between natural organic matter (NOM) and iron that caused the observed chromatographic effect. This study was divided into three main stages: a) characterization study on Vars groundwater and its treatment system; b) study of the competitive adsorption of iron with NOM in Vars groundwater; and c) evaluation of the rapid small-scale column test (RSSCT) for predicting the full-scale GAC column breakthroughs. The characterization of Vars groundwater showed that ferrous iron was found to be the dominant iron species, representing 90% of the total iron, and that 15 - 35% of the iron was complexed with NOM. It was hypothesized that the chromatographic displacement of iron from the GAC columns was caused by NOM-iron complexes; however, field mini-column experiments showed this was not the case. Thus, competitive adsorption between iron and NOM was seen as the more likely cause of the chromatographic effect. The adsorption capacity of ferrous iron in Vars raw water was less than that in organic-free water by a factor of 7 due to the competition with NOM over the GAC adsorbing sites. However, the NOM adsorption capacity was not reduced due to the presence of ferrous iron. It was hypothesized that ideal adsorption solution theory (IAST) models, which have been successful in describing competitive adsorption between target organic compounds and NOM, could model the competition between an inorganic compound such as ferrous iron and NOM. The hypothesis was proved to be correct, and the adsorption isotherm of iron in competition with NOM in Vars groundwater was simulated very well by several versions of the IAST model. However, none of the models were capable of simulating the competitive adsorption of NOM and ferrous iron simultaneously. Since the presence of iron did not significantly reduce the adsorption capacity of NOM, a simplified approach of using the single-solute NOM isotherm to represent the competitive NOM isotherm was recommended. The performance of the rapid small-scale column test (RSSCT) was evaluated in order to simulate the iron chromatographic effect observed at Vars' full-scale GAC column. The RSSCT was not capable of predicting the iron phenomenon and the test proved to be problematic due to the oxidation and precipitation of iron within the small voids between the small-scale column's GAC particles. The RSSCT, using constant and linear diffusivities, were applied to simulate the NOM adsorption after greensand treatment. Integrating both diffusivities, the tests predicted the onset and slope of the NOM breakthrough up to 10-L water treated/g GAC, which is equivalent to 250 days of operation time for the full-scale column. However, the NOM breakthroughs deviated beyond that point and the RSSCT using constant diffusivity underestimated the column performance greatly. On the other hand, the linear diffusivity RSSCT underestimated the performance to a lesser degree and its NOM breakthrough was quite parallel to the full-scale performance with lower NOM removals of 15%. The higher long-term NOM removal in the full-scale system may be explained by biodegradation, a phenomenon that was not considered by the short duration of RSSCT.
Author | : Sirshendu De |
Publisher | : The Energy and Resources Institute (TERI) |
Total Pages | : 306 |
Release | : 2012-01-01 |
Genre | : Technology & Engineering |
ISBN | : 8179933830 |
Download Arsenic Removal from Contaminated Groundwater Book in PDF, ePub and Kindle
Contamination of groundwater with arsenic is being considered a pervasive and critical issue in recent years. Large areas in India, Bangladesh, South East Asia, and other parts of the world are suffering from this problem. Arsenic Removal from Contaminated Groundwater presents a comprehensive discussion on various important issues, including state-of-the-art arsenic removal technologies, preparation and performance analysis of laterite, and scale-up issues and design of a household filter. It also expounds the potentiality of raw laterite and treated laterite as low-cost arsenic adsorbents. The efficiency of adsorbent capacity is evaluated using real arsenic contaminated groundwater collected from an affected area in West Bengal, India. The topic is an emerging area and most of the work presented has the potential of field application.
Author | : |
Publisher | : |
Total Pages | : 112 |
Release | : 2005 |
Genre | : Carbon, Activated |
ISBN | : |
Download Rapid Small Scale Column Testing for Evaluating Arsenic Adsorbents Book in PDF, ePub and Kindle
Author | : |
Publisher | : DIANE Publishing |
Total Pages | : 164 |
Release | : 2005 |
Genre | : Arsenic |
ISBN | : 1422330028 |
Download Removal of Arsenic in Drinking Water Book in PDF, ePub and Kindle