Based on results of field testing conducted by the U.S. Department of Energy's National Energy Technology Laboratory (DOE/NETL), this article provides preliminary costs for mercury control via conventional activated carbon injection (ACI), brominated ACI, and conventional ACI coupled with the application of a sorbent enhancement additive (SEA) to coal prior to combustion. The economic analyses are reported on a plant-specific basis in terms of the cost required to achieve low (50%), mid (70%), and high (90%) levels of mercury removal "above and beyond" the baseline mercury removal achieved by existing emission control equipment. In other words, the levels of mercury control are directly attributable to ACI. Mercury control costs via ACI have been amortized on a current dollar basis. Using a 20-year book life, levelized costs for the incremental increase in cost of electricity (COE), expressed in mills per kilowatt-hour (mills/kWh), and the incremental cost of mercury control, expressed in dollars per pound of mercury removed ($/lb Hg removed), have been calculated for each level of ACI mercury control. For this analysis, the increase in COE varied from 0.14 mills/kWh to 3.92 mills/kWh. Meanwhile, the incremental cost of mercury control ranged from $3810/lb Hg removed to $166000/lb Hg removed.

In contrast to past regulations for power plant air pollutants, there is growing interest in a multi-pollutant perspective that would simultaneously address criteria pollutants, air toxics, and greenhouse gases. This paper addresses some of the key technical and economic questions needed to assess policy proposals, namely: What technical options are available to control each of these pollutants? What plant-level interactions must be considered in evaluating the feasibility and cost of alternative control measures? What advantages are there to multi-pollutant control strategies? The Integrated Environmental Control Model (IECM) developed for the U.S. Department of Energy’s National Energy Technology Laboratory (DOE/NETL) is used to obtain illustrated quantitative estimates of the cost and emissions impacts of interactions among technologies for multi-pollutant controls.

The U.S. Environmental Protection Agency (EPA) has announced it will regulate mercury emissions from coal-fired power plants, with proposed regulations to be issued in 2003. The feasibility and cost of achieving mercury emission reductions is thus a subject of considerable current interest. To assess mercury control options, the Integrated Environmental Control Model (IECM) developed for the U.S. Department of Energy’s National Energy Technology Laboratory (DOE/NETL) has been expanded to include performance and cost models for a variety of mercury control options. These preliminary models are based on a review of recent mercury information collection request (ICR) data, and on the results of pilot plant studies and other data sources employing carbon injection with and without flue gas humidification. Illustrative results using the IECM show that the feasibility and cost of achieving different levels of mercury reduction depend strongly on the fuel type and power plant configuration. In most cases, the presence of a flue gas desulfurization (FGD) unit or a selective catalytic reduction (SCR) system can have a significant (beneficial) impact on mercury removal efficiency and cost. However, because of limitations on the scale and coverage of available data, there is considerable uncertainty in current estimates of mercury control costs and capabilities. Current models and estimates will be refined as new data become available from ongoing programs.

In contrast to past regulations for power plant air pollutants, there is growing interest in a multi-pollutant perspective that would simultaneously address criteria pollutants, air toxics, and greenhouse gases. This paper addresses some of the key technical and economic questions needed to assess policy proposals, namely: What technical options are available to control each of these pollutants? What plant-level interactions must be considered in evaluating the feasibility and cost of alternative control measures? What advantages are there to multi-pollutant control strategies? The Integrated Environmental Control Model (IECM) developed for the U.S. Department of Energy's National Energy Technology Laboratory (DOE/NETL) is used to obtain illustrated quantitative estimates of the cost and emissions impacts of interactions among technologies for multi-pollutant controls. BACKGROUND

The U.S. Environmental Protection Agency (EPA) has announced it will regulate mercury emissions from coal-fired power plants, with proposed regulations to be issued in 2003. The feasibility and cost of achieving mercury emission reductions is thus a subject of considerable current interest. To assess mercury control options, the Integrated Environmental Control Model (IECM) developed for the U.S. Department of Energy's National Energy Technology Laboratory (DOE/NETL) has been expanded to include performance and cost models for a variety of mercury control options. These preliminary models are based on a review of recent mercury information collection request (ICR) data, and on the results of pilot plant studies and other data sources employing carbon injection with and without flue gas humidification. Illustrative results using the IECM show that the feasibility and cost of achieving different levels of mercury reduction depend strongly on the fuel type and power plant configuration. In most cases, the presence of a flue gas desulfurization (FGD) unit or a selective catalytic reduction (SCR) system can have a significant (beneficial) impact on mercury removal efficiency and cost. However, because of limitations on the scale and coverage of available data, there is considerable uncertainty in current estimates of mercury control costs and capabilities. Current models and estimates will be refined as new data become available from on- going programs.

Mercury emissions from coal-fired power plants have been extensively evaluated for nearly 10 years to determine possible regulation by the Environmental Protection Agency (EPA). Under a court order, a determination will be made on whether it is appropriate and necessary to regulate toxic air pollutant emissions (focusing on mercury) from coal-fired utility boilers by December 15, 2000, If it is determined that regulations are necessary, then the regulatory process will have a fixed timetable. A proposed regulation will be due no later than December 15, 2003, and promulgated no later than December 15, 2004. The utility industry regulatory compliance must be in place by December 2007 since the Clean Air Act requires that sources come into compliance with Maximum Achievable Control Technology (MACT) 3 years after promulgation of the regulations. While it is recognized that the main driver for regulation is the potential risk to human health and that this risk is currently being examined by a number of health-based organizations, the actual form of any regulation would likely be dependent upon the availability of cost-effective control technologies. Furthermore, the diverse nature of the coal-fired utility industry will likely limit the applicability and cost-effectiveness of any given technology for the current boiler population.In light of a potential regulatory determination, this paper examines a few control options that warrant further consideration. A preliminary assessment of mercury capture technologies and associated costs is conducted for sorbent injection technology. Sorbent-based technologies that may be amenable for mercury control include: (1) sorbent injection with and without spray cooling upstream of existing particulate control devices (i.e., electrostatic precipitators and fabric filters): and (2) sorbent injection with and without spray cooling associated with additional control devices designed to augment particulate collection in a primary particulate control device. Important design criteria for each of the control systems are critically assessed for operability, maintainability, and reliability, with the projected impacts of the control system on power plant operations being evaluated. The sorbent-based technology discussed in this paper focuses on the injection of activated carbon associated with the various particulate control devices used in the utility industry. The paper also addresses the next steps and revisions needed to accurately assess possible cost impacts to the utility industry as the mercury control options mature in their development. (C) 2000 Published by Elsevier Science B.V. All rights reserved.

Based on the available evidence of health effects, the U.S. Environmental Protection Agency (EPA) has been evaluating the need to regulate mercury releases to the environment. In response to the congressional mandates in The 1990 Clean Air Act Amendments (CAAA), the EPA has issued the Mercury Study Report and the Study of Hazardous Air Pollutant Emissions from Electric Utility Steam Generating Units Report. In spite of the enormous effort represented by these reports, as well as the efforts of both the U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI), in conducting the field measurement programs that form the basis for these reports, a definitive answer on the need for mercury regulation has not been found. However, the EPA, as well as other regulatory agencies and health researchers, have suggested a "plausible link" between anthropogenic sources emitting mercury and the methylation, bioaccumulation in the food chain, and adverse health effects in humans and wildlife.

Purpose: Post-prostatectomy incontinence has an incidence of 5 to 12% and greatly affects quality of life. Since the approval of glutaraldehyde cross-linked collagen there is a renewed interest in injectable urethral bulking agents. We investigated the long-term efficacy and prognostic criteria for transurethral collagen injection therapy for men with post-prostatectomy incontinence.Materials and Methods: From November 1993 to May 1995, 62 men with post-prostatectomy incontinence (54 after radical prostatectomy and 8 after transurethral resection of the prostate) were treated with collagen via a transurethral approach. Median followup was 29.0 months from the date of the last injection procedure.Results: Social continence was defined as dry or minimal leakage requiring at most 1 pad daily with activity. Of 62 patients 38.7% achieved social continence and 8.1% became totally dry. The success rate was 35.2 for radical prostatectomy versus 62.5% for transurethral prostatic resection patients, Of the patients who achieved social continence with at least 1-year followup 23 (60.9%) remained so with no further treatment. At 2-year followup 21 patients (42.8%) maintained social continence. The success rate was 27.3% for those who wore a penile clamp or condom catheter before treatment (3 of 11 patients), and only 21.4% for those who underwent transurethral incision of a bladder neck contracture (3 of 14), A median of 4 injection procedures and 20.0 ml. collagen were required to achieve social continence.Conclusions: Transurethral collagen injection therapy is a reasonable treatment option for post-prostatectomy incontinence in select patients in whom more conservative therapy has failed. However, patients who have required a penile clamp, experienced continuous leakage or undergone transurethral incision of a bladder neck contracture are unlikely to respond well to this treatment.

New data and theory are presented for describing dispersed solids in slurry bubble columns. Axial solids concentration distributions were measured in a 0.108 m.i.d. slurry bubble column apparatus operated at steady-state conditions. Slurry and gas superficial velocities ranged from 0.0 to 0.02 m/s and 0.03 to 0.20 m/s, respectively. The liquid-phase was either water or ethanol, and the solid-phase consisted of narrow-sized fractions of glass spheres.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTwo-bubble class model for churn turbulent bubble-column reactorYatish T. Shah, Sebastian Joseph, Dennis N. Smith, and John A. RuetherCite this: Ind. Eng. Chem. Process Des. Dev. 1985, 24, 4, 1096–1104Publication Date (Print):October 1, 1985Publication History Published online1 May 2002Published inissue 1 October 1985https://pubs.acs.org/doi/10.1021/i200031a034https://doi.org/10.1021/i200031a034research-articleACS PublicationsRequest reuse permissionsArticle Views229Altmetric-Citations25LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOn the behavior of the gas phase in a bubble column with ethanol-water mixturesYatish T. Shah, Sebastian Joseph, Dennis N. Smith, and John A. RuetherCite this: Ind. Eng. Chem. Process Des. Dev. 1985, 24, 4, 1140–1148Publication Date (Print):October 1, 1985Publication History Published online1 May 2002Published inissue 1 October 1985https://pubs.acs.org/doi/10.1021/i200031a041https://doi.org/10.1021/i200031a041research-articleACS PublicationsRequest reuse permissionsArticle Views371Altmetric-Citations57LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

Mercury emissions from coal-fired power plants are currently being evaluated by the Environmental Protection Agency (EPA) for possible regulation. Because of the possibility for such regulation, this paper discusses a preliminary assessment of mercury capture technologies and associated costs based on commercially available technology. Sorbent-based technologies that may be amenable for mercury control include: sorbent injection; sorbent injection with spray cooling; and sorbent injection with spray cooling and particulate collection. Important design criteria for each of these systems are critically assessed for operability, maintainability, and reliability. The projected impacts of the control system on power plant operations are also evaluated.

In contrast to past regulations for power plant air pollutants, there is growing interest in a multi-pollutant perspective that would simultaneously address criteria pollutants, air toxics, and greenhouse gases. This paper addresses some of the key technical and economic questions needed to assess policy proposals using the Integrated Environmental Control Model (IECM) developed for the U.S. Department of Energy's National Energy Technology Laboratory (DOE/NETL). BACKGROUND