In Situ Regeneration of Granular Activated Carbon (GAC) for Natural Organic Matter (NOM) Removal 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 In Situ Regeneration of Granular Activated Carbon (GAC) for Natural Organic Matter (NOM) Removal PDF full book. Access full book title In Situ Regeneration of Granular Activated Carbon (GAC) for Natural Organic Matter (NOM) Removal by Rohiniben Patel. Download full books in PDF and EPUB format.
Author: Rohiniben Patel Publisher: ISBN: Category : Carbon, Activated Languages : en Pages : 150
Book Description
"Sequentially-loaded and regenerated granular activated carbon (GAC) was studied to determine the efficiency of regenerative materials to restore the adsorption capacity. GAC was loaded with the Bray pond water containing natural organic matter (NOM) using rapid small scale column test (RSSCT) column. The exhausted carbon was NOM was then regenerated with different regenerants, and regenerated carbon was again reloaded with Bray pond water. The regeneration process was done in situ. Eight regenerants were used for this purpose and they were compared based on their regeneration efficiency. The most effective regenerant observed was acetic acid"--Abstract, leaf iii.
Author: Rohiniben Patel Publisher: ISBN: Category : Carbon, Activated Languages : en Pages : 150
Book Description
"Sequentially-loaded and regenerated granular activated carbon (GAC) was studied to determine the efficiency of regenerative materials to restore the adsorption capacity. GAC was loaded with the Bray pond water containing natural organic matter (NOM) using rapid small scale column test (RSSCT) column. The exhausted carbon was NOM was then regenerated with different regenerants, and regenerated carbon was again reloaded with Bray pond water. The regeneration process was done in situ. Eight regenerants were used for this purpose and they were compared based on their regeneration efficiency. The most effective regenerant observed was acetic acid"--Abstract, leaf iii.
Author: Natalia Fischer Publisher: ISBN: Category : Carbon, Activated Languages : en Pages : 156
Book Description
Granular activated carbon (GAC) is effectively used to remove natural organic matter (NOM) and to assist in the removal of disinfection byproducts (DBPs) and their precursors. However, operation of GAC is cost- and labor-intensive due to frequent media replacement. Optimizing the use of GAC is necessary to ensure treatment efficiency while reducing costs. This dissertation presents four strategies to reduce improve GAC usage while reducing formation of DBPs. The first part of this work adopts Rapid Small Scale Tests (RSSCTs) to evaluate removal of molecular weight fractions of NOM, characterized using size exclusion chromatography (SECDOC). Total trihalomethanes (TTHM), haloacetic acids (HAA5) and haloacetonitriles (HAN) formation were quantified after treatment with GAC. Low MW NOM was removed preferentially in the early bed volumes, up until exhaustion of available adsorption sites. DBP formation potential lowered with DOC removal. Chlorination prior to GAC is investigated in the second part of this work as a strategy to increase removal of NOM and DBP precursors. Results showed lower TTHM formation in the effluent of the GAC treatment when pre-chlorination was adopted, meaning this strategy could help optimize and extend the bed life if GAC filters. The third part of this work investigates in-situ GAC regeneration as an alternative to recover adsorption capacity of field-spent GAC that could potentially offer new modes of operation for water treatment facilities while savng costs with reactivation of spent GAC in an external facility. Field-spent GACs were treated with different oxidant solutions and recovery in adsorption capacity was evaluated for NOM and for two micro pollutants. Recovery of GAC adsorption capacity was not satisfactory for most of conditions evaluated. This indicates that in-situ GAC regeneration could be more effective when the adsorbates are present at high concentrations. Lastly, this work investigates the impact of low molecular weight polyDADMAC on N-nitrosodimethylamine (NDMA) formation. Water treatment facilities rely on polyDADMAC as a coagulant aid to comply with NOM removal and turbidity requirements. Since polymer-derived NDMA precursors are not removed by GAC, it is essential to optimize the use and synthesis of polyDADMAC to reduce NDMA precursors during water treatment.
Author: Afsoon Taghizadehgan Publisher: ISBN: Category : Languages : en Pages :
Book Description
Natural organic matters (NOM) interact with disinfectants and produce disinfection by-products (DBPs). One of the best available technologies to remove NOM from water to reduce DBPs formation is adsorption with activated carbon. In this study, the removal of NOM from pond water was studied using powder activated carbon (PAC), and the granular activated carbon (GAC) generated from Corner Brook Pulp and Paper (CBPP) fly ash as raw material. PAC was used in batch tests and water pH, temperature, and volume was considered as variables to determine optimized conditions for NOM removal applying response surface method (RSM); it was concluded that water pH and volume have significant effects on NOM removal. CBPP was combined with bitumen as a binder to produce GAC. Effect of binder to carbon ratio, calcination and steam activation temperature, the temperature increasing rate, and steam activation time were studied to produce GAC with high BET surface area and efficient hardness. Granules with 30:70 binder to carbon ratio, calcinated at 750°C, activated at 950°C for 3 hours with 15°C/min of heating rate were found to be ideal for GAC production for NOM removal. Column tests for NOM removal were conducted using produced GAC. Results indicate that the produced GAC is effective for 60% NOM removal. Follow-up chlorination experiments illustrate that the formation of DBPs (THMs and HAAs) were significantly reduced. Used GAC was regenerated using RSM design at different regeneration temperature, time, and steam flow. The results show that regeneration at 916°C for 43 minutes under 350 mL/min of steam would lead to optimum regeneration conditions.
Author: James Helfrich Publisher: ISBN: Category : Languages : en Pages : 93
Book Description
This study provides cost estimates of construction and operation for granular activated carbon (GAC) adsorption of total organic carbon (TOC), and packed tower aeration (PTA) for air stripping of trihalomethanes (THMs). Costs were developed by employing software published by the United States Environmental Protection Agency (USEPA) through its Drinking Water Research Division (DWRD). Cost estimation for both methods required preliminary GAC and PTA designs based on data collected in the field and from earlier published sources, as well as modifications to the software used in this study. The resultant designs were focused on compliance with certain aspects of the Stage 2 Disinfection By-Product Rule (Stage 2 DBPR) for THM and haloacetic acid (HAA) concentrations in drinking water. Formation of disinfection by-products (DBPs) occurs when natural organic matter (NOM) found in water sources reacts with disinfectants, typically chlorine based, that are used for the inactivation of water-borne pathogens. DBPs included several groups of compounds that, when ingested, are known to be carcinogenic and have been linked to other serious health effects. Two principle locations were used in this study to represent a medium system (serving 10,000 to 99,999 people) and a large system (serving 100,000 or more people). Overall system cost estimates for GAC adsorption were between 24 and 41 cents per 1000 gallons with an apparent economy of scale existing for larger systems. Investigations into GAC reactivation suggest that off-site reactivation is more cost effective for small to medium systems while some type of on-site reactivation would be a more cost effective method for larger systems. Overall PTA system cost estimates were between 8 and 9.6 cents per 1000 gallons. Both methods are effective at THM control while GAC adsorption has the added ability to reduce non-volatile DBPs and naturally occurring material (NOM), as well as reducing taste and odor problems if present.
Author: Ferhan Cecen Publisher: John Wiley & Sons ISBN: 3527639454 Category : Science Languages : en Pages : 409
Book Description
This monograph provides comprehensive coverage of technologies which integrate adsorption and biological processes in water and wastewater treatment. The authors provide both an introduction to the topic as well as a detailed discussion of theoretical and practical considerations. After a review of the basics involved in the chemistry, biology and technology of integrated adsorption and biological removal, they discuss the setup of pilot- and full-scale treatment facilities, covering powdered as well as granular activated carbon. They elucidate the factors that influence the successful operation of integrated systems. Their discussion on integrated systems expands from the effects of environmental to the removal of various pollutants, to regeneration of activated carbon, and to the analysis of such systems in mathematical terms. The authors conclude with a look at future needs for research and develoment. A truly valuable resource for environmental engineers, environmental and water chemists, as well as professionals working in water and wastewater treatment.
Author: Clark Publisher: CRC Press ISBN: 9780873711142 Category : Technology & Engineering Languages : en Pages : 358
Book Description
This new book presents design, cost, and performance information on the application of GAC in drinking water, including the use of GAC both in the U.S. and overseas. Various design concepts for the unit operations that make up the GAC process are presented in 11 comprehensive, complete chapters, including a special chapter that provides cost equations and comparative cost studies for full scale application of GAC.
Author: Carla De Las Casas Publisher: ISBN: Category : Languages : en Pages : 430
Book Description
Fenton-dependent recovery of carbon initially saturated with one of several chlorinated aliphatic contaminants was studied in batch and continuous-flow reactors. A specialty carbon, URV-MOD 1 (Calgon) was employed to minimize non-productive H2O2 demand - that which does not yield hydroxyl or superoxide radicals. Enhancement of PCE degradation kinetics by ferric iron addition is limited by iron solubility, even at relatively low pH. Quinone addition increased the pseudo-first-order rate constant for PCE loss temporarily. Only copper addition sustainably enhanced the specific rate of PCE loss. For copper-to-iron molar ratios of 0.25 to 5, the pseudo-first-order rate constant for PCE transformation was increased by a factor of 3.5. It is apparent that the effect of copper addition on Fenton-dependent reaction rates is complex, and involves a shift in chemical mechanism, as indicated by the differing slopes in the Arrhenius plot (with and without copper).A mathematical model was developed to evaluate the effect of operational parameters ([Fe(III)]T:[H2O2]o ratio and pH) on degradation kinetics and optimize the PCE degradation process in homogeneous reaction mixtures. The model simulated experimental degradation of the organic target in a homogeneous Fenton-reaction system. The model requires further refinement to simulate Fenton's systems in which ions in solution (such as sulfate and chloride) play significant roles. In continuous-flow reactors, Fenton's reagents were cycled through spent GAC in columns to degrade one of seven chlorinated compounds tested. The contaminant with the weakest adsorption characteristics, methylene chloride, was 99% lost from the carbon surface during a 14-hour regeneration period. At the field site, the GAC was saturated with gases containing TCE and PCE from a soil vapor extraction (SVE) system. In the field, up to 95% of the sorbed TCE was removed from GAC during regeneration periods of 50-60 hours. Recovery of PCE-loaded GAC was significantly slower. Column experiments show that there is minimal loss of carbon adsorption capacity during Fenton treatment and that the rate of GAC regeneration is compound specific. Scoping-level cost estimates indicated that field use of Fenton regeneration is not cost effective without optimization and/or iron surface amendments, except in the case of the most soluble VOCs.
Author: Rohiniben Patel
Author: Rohiniben Patel
Author: Jeff McEwen
Author: Natalia Fischer
Author: Juan Zhang
Author: Afsoon Taghizadehgan
Author: James Helfrich
Author: Ferhan Cecen
Author: Clark
Author: Stuart M. Hooper
Author: Carla De Las Casas