This chapter describes the specifics of the cement manufacturing process and the corresponding effects of the process chemistry and temperatures within the kiln system on mercury speciation. The discussion includes the current state of the study of mercury in the industry and knowledge on mercury control. Cement manufacturing is performed in a large-scale industrial production process using large volumes of raw materials and fuels. The kiln system is where the key process step occurs, where a specific combination of minerals is heated to a temperature of about 1500ºC in a large, cylindrical, rotating, refractory-lined kiln, and associated equipment, depending on the type of kiln system. Mercury can enter the kiln system from two sources - the raw material and the fuel. The possible approaches can be considered for mercury control, which are based on the current state of mercury control knowledge as applied to the cement process.
The objective of the project is to develop the prototype of an advanced petrochemical process heater that uses radiant ceramic fiber burners. The heat input of the prototype heater will be about 10 MMBtu/hr, and the heater will be capable of firing either natural gas or refinery process gas. The heater will be designed to take full advantage of the fiber burner's radiant heat-transfer characteristics, an opportunity unavailable in the retrofit of an existing heater with fiber burners. During the third year of the project, a new field-test site was selected. The new site is Evergreen Oil Co. of Newark, California. Also during the year, the conceptual design of the heater and the customized Pyrocore burner were finalized by Alzeta and KTI Corp. (a major subcontractor). The detailed hardware design will begin at the start of the fourth year (October 1986). Installation at the field-test site is scheduled for February-March, 1987.
Results are presented of a study to identify capital costs associated with converting industrial and utility boilers from conventional high-sulfur fossil fuels to low-sulfur products from selected coal conversion processes. The boilers of concern include all industrial and utility size equipment in the 10 to the 7th power to 10 to the 10th power Btu/hr capacity range. The substitute fuels include solvent refined coal (SRC) in the solid and hot liquid (melted) phases as well as lower-Btu gas. The cost assessment methods used in the study showed that conversion to liquid SRC is the most expensive alternative. Converting coal-fired boilers to solid SRC is the least expensive alternative for these types of boilers. Between the costs of converting to SRC in either phase lie those costs for converting to the gaseous fuels. A significant result of the study is that the costs of all conversion strategies increase exponentially with boiler capacity: cost appears to be a weak function of boiler design. (GRA)
Understanding organic constituent partitioning between the gas and solid phases of cement kiln emissions is important from both a risk assessment and organic emissions control perspective. The extent to which organic constituents partition to either phase is highly dependent on the environment in which the constituents are exposed. From a theoretical standpoint, the partitioning of an organic constituent is dependent on variables such as vapor pressure, and particle surface area and activity. For risk assessments where mechanisms such as vapor phase transport and particle deposition rate are significant modeling variables, the fate and transport of organic constituents are evaluated at ambient air conditions. At stack conditions, particle characteristics will not be significantly different than at ambient conditions. However, vapor pressures of organic constituents, which are a function of temperature, may be significantly different at ambient versus stack conditions. As a result, the fraction of an organic constituent adsorbed to available particulate matter may approach one at ambient conditions, but be closer to zero at stack conditions. The temperature dependence on partitioning has important implications for relatively high molecular weight and low volatile organic constituents such as 2,3,7,8 tetrachlorodibenzo-p-dioxin (molecular weight = 322 g/mol) because they may not be adsorbed tomore » particulate exiting the stack, but may become adsorbed at lower temperature ambient conditions.« less
Supervised exercise programs are used to treat intermittent claudication (IC). Home-based exercise programs have been developed to lower barriers to participation. We studied the effects of one such exercise program (TeGeCoach) on self-reported walking ability in patients with IC.
To determine whether a palliative care (PC) consult service in a long-term care (LTC) facility would result in a more favorable course of treatment and clinical outcomes for participating residents.We used a historical control design within a single LTC facility. Outcome data and potential confounding variables were obtained using the Minimum Data Set. (Health Care Financing Administration. (1995). Long term care resident assessment instrument user's manual version 2.0. Rockville, MD: Health Care Financing Administration.) Residents who died during the period of the PC service (2007-2009) were compared with matched residents who died in the year prior (2006, historical controls). The analysis sample included 250 residents (125 PC residents, 125 non-PC historical control residents). Our main analysis focused on a composite outcome based on utilization patterns, depression, and pain and other clinical indicators. We analyzed change on this component score (and the individual outcomes) over a 1-year period.PC residents experienced a significant reduction in emergency room (ER) visits (p < .001) and depression (p = .031). Change in the composite score indicated a significant difference over time between the 2 groups (p = .013).Although limited to 1 facility and drawn from a quasi-experimental design, the results demonstrate the potential for improved quality of care with PC consults. The PC team was effective in reducing ER visits and depression and promoted more appropriate care resulting in more favorable clinical outcomes toward the resident's end of life.
This paper will describe the development of a predictive mercury model for emissions from a cement plant using historical raw material input parameters and CEM emission data. To quantify the mercury emissions, mass balance and partitioning coefficients are determined based upon quantitative measurements of kiln system parameters and monitoring of emissions by use of continuous emissions monitoring (CEM) data. The information gathered is used to develop a model that will predict changes in emissions based upon changes in raw material input parameters and modifications in kiln operating conditions. The model results may help to determine the effectiveness of changing operating parameters for controlling mercury emissions from kiln operations. Model development and operating parameters that influence the results will be discussed.
Article Free Access Share on The new design: the changing role of industrial engineers in the design process through the use of simulation Authors: Deidra L. Donald Deneb Robotics, Inc., 5500 New King Street, Troy, MI Deneb Robotics, Inc., 5500 New King Street, Troy, MIView Profile , Nick Andreou General Motors Corporation, 7000 Chicago Roadm, Warren, MI General Motors Corporation, 7000 Chicago Roadm, Warren, MIView Profile , Jeffrey Abell DaimlerChrysler Corporation, 800 Chrysler Drive, Auburn Hills, MI DaimlerChrysler Corporation, 800 Chrysler Drive, Auburn Hills, MIView Profile , Robert J. Schreiber The Boeing Company, P.O. Box 516, St. Louis, MO The Boeing Company, P.O. Box 516, St. Louis, MOView Profile Authors Info & Claims WSC '99: Proceedings of the 31st conference on Winter simulation: Simulation---a bridge to the future - Volume 1December 1999 Pages 829–833https://doi.org/10.1145/324138.324530Online:01 December 1999Publication History 3citation352DownloadsMetricsTotal Citations3Total Downloads352Last 12 Months5Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF
The EPA has speculated that populations near high potential risk industries may be predominantly low income or minority status, and that this population is at a greater health risk with respect to protection from environmental hazards. The role of industry in creating environmental injustice through the location and siting of facilities potentially posing environmental hazards is vastly unsupported. Industry selects a location based on economics not demographics. Residents select a home based on geographic preference; the housing they can afford; as well as proximity to their job, schools, and activities. If demographic imbalance is occurring disproportionately in locations containing high health risk industries, the strongest factors in the equation are local economy, zoning, and politics; as well as urban sprawl. When the concept of social injustice is evaluated in regard to the cement industry, their influence on environmental inequity becomes increasingly obscure. Cement operations are dependent upon raw materials which are obtained from nearby quarries. Most facilities were built decades ago in undeveloped locations with limestone formations. Indeed many facilities still exist in this rural state. Population risk evaluations should be based solely on exposure potential and the level of hazard present. Within the cement industry, facility operations utilize themore » best available technology, as well as the best available pollution control practices. Technology and operating practices are developed through continual research and development on-site. The industry applies these technologies uniformly and does not base implementation decisions on demographics. The cement industry`s commitment to environmental considerations is implemented regardless of race or income factors.« less
