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Combustion properties of Kraft Black Liquors

Description: In a previous study of the phenomena involved in the combustion of black liquor droplets a numerical model was developed. The model required certain black liquor specific combustion information which was then not currently available, and additional data were needed for evaluating the model. The overall objectives of the project reported here was to provide experimental data on key aspects of black liquor combustion, to interpret the data, and to put it into a form which would be useful for computational models for recovery boilers. The specific topics to be investigated were the volatiles and char carbon yields from pyrolysis of single black liquor droplets; a criterion for the onset of devolatilization and the accompanying rapid swelling; and the surface temperature of black liquor droplets during pyrolysis, combustion, and gasification. Additional information on the swelling characteristics of black liquor droplets was also obtained as part of the experiments conducted.
Date: April 1, 1993
Creator: Frederick, W.J. Jr. & Hupa, M. (Aabo Akademi, Turku (Finland))
Partner: UNT Libraries Government Documents Department

Black liquor combustion validated recovery boiler modeling, five-year report

Description: The objective of this project was to develop a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The project originated in October 1990 and was scheduled to run for four years. At that time, there was considerable emphasis on developing accurate predictions of the physical carryover of macroscopic particles of partially burnt black liquor and smelt droplets out of the furnace, since this was seen as the main cause of boiler plugging. This placed a major emphasis on gas flow patterns within the furnace and on the mass loss rates and swelling and shrinking rates of burning black liquor drops. As work proceeded on developing the recovery boiler furnace model, it became apparent that some recovery boilers encounter serious plugging problems even when physical carryover was minimal. After the original four-year period was completed, the project was extended to address this issue. The objective of the extended project was to improve the utility of the models by including the black liquor chemistry relevant to air emissions predictions and aerosol formation, and by developing the knowledge base and computational tools to relate furnace model outputs to fouling and plugging of the convective sections of the boilers. The work done to date includes CFD model development and validation, acquisition of information on black liquor combustion fundamentals and development of improved burning models, char bed model development, and model application and simplification.
Date: August 1, 1996
Creator: Grace, T.M.; Frederick, W.J.; Salcudean, M. & Wessel, R.A.
Partner: UNT Libraries Government Documents Department

Black liquor combustion validated recovery boiler modeling: Final year report. Volume 4 (Appendix IV)

Description: This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 4 contains the following appendix sections: Radiative heat transfer properties for black liquor combustion -- Facilities and techniques and Spectral absorbance and emittance data; and Radiate heat transfer determination of the optical constants of ash samples from kraft recovery boilers -- Calculation procedure; Computation program; Density determination; Particle diameter determination; Optical constant data; and Uncertainty analysis.
Date: August 1, 1998
Creator: Grace, T.M.; Frederick, W.J.; Salcudean, M. & Wessel, R.A.
Partner: UNT Libraries Government Documents Department

Black liquor combustion validated recovery boiler modeling: Final year report. Volume 1 (Main text and Appendix I, sections 1--4)

Description: This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 1 contains the main body of the report and the first 4 sections of Appendix 1: Modeling of black liquor recovery boilers -- summary report; Flow and heat transfer modeling in the upper furnace of a kraft recovery boiler; Numerical simulation of black liquor combustion; and Investigation of turbulence models and prediction of swirling flows for kraft recovery furnaces.
Date: August 1, 1998
Creator: Grace, T.M.; Frederick, W.J.; Salcudean, M. & Wessel, R.A.
Partner: UNT Libraries Government Documents Department

Black liquor combustion validated recovery boiler modeling: Final year report. Volume 3 (Appendices II, sections 2--3 and III)

Description: This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 3 contains the following appendix sections: Formation and destruction of nitrogen oxides in recovery boilers; Sintering and densification of recovery boiler deposits laboratory data and a rate model; and Experimental data on rates of particulate formation during char bed burning.
Date: August 1, 1998
Creator: Grace, T.M.; Frederick, W.J.; Salcudean, M. & Wessel, R.A.
Partner: UNT Libraries Government Documents Department

Black liquor combustion validated recovery boiler modeling: Final year report. Volume 2 (Appendices I, section 5 and II, section 1)

Description: This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 2 contains the last section of Appendix I, Radiative heat transfer in kraft recovery boilers, and the first section of Appendix II, The effect of temperature and residence time on the distribution of carbon, sulfur, and nitrogen between gaseous and condensed phase products from low temperature pyrolysis of kraft black liquor.
Date: August 1, 1998
Creator: Grace, T.M.; Frederick, W.J.; Salcudean, M. & Wessel, R.A.
Partner: UNT Libraries Government Documents Department

Control of the accumulation of non-process elements and organic compounds in pulp mills with bleach filtrate reuse. Quarterly report, October--December 1996

Description: A portion of each filtrate sample was freeze-dried and the resulting solids were analyzed for ash content. Adsorption experiments with calcium and barium were carried at 70{degrees}C in a temperature controlled incubator under continuous mixing in order to simulate the environment experienced by brownstock as it moves through the Q stage. In the calcium experiments, it was difficult to accurately determine the calcium adsorbed on the pulp by measuring the depletion of calcium in the aqueous phase. Consequently, the technique was modified. In the modified technique, the calcium-adsorbed pulp is acid washed again to release the calcium. The calcium concentration in the washings is measured, and the calcium adsorbed on the pulp is estimated by material balance. Measurement of calcium adsorption on the brownstock pulp fibers from the L-P/Samoa mill have been obtained.
Date: December 31, 1996
Creator: Frederick, W.J.; Laver, M.L. & Rorrer, G.L.
Partner: UNT Libraries Government Documents Department

Control of the accumulation of non-process elements and organic compounds in pulp mills with bleach filtrate reuse. Quarterly report 3, January--March, 1997

Description: Progress during this quarter is described on four tasks. The first task involves the recovery of organic matter from bleach effluents and black liquors, separation of carbohydrates and lignin degradation products, analysis of functional groups, and characterization of carbohydrate polymers. Progress in the second task was made in the selection of model compounds. Several subtasks are complete in Task 3, but the paper summarizes progress made in the determination of the residual hemicellulose content in the pulp samples. Finally, results are given for the measurement of metal adsorption isotherms on wood pulp. Goals for the next quarter are listed.
Date: May 1, 1997
Creator: Frederick, W.J.; Laver, M.L. & Rorrer, G.L.
Partner: UNT Libraries Government Documents Department

Black liquor combustion validated recovery boiler modeling: Final year report. Volume 5 (Appendix V)

Description: This project was initiated in October 1990, with the objective of developing and validating a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 5 contains model validation simulations and comparison with data.
Date: August 1, 1998
Creator: Grace, T.M.; Frederick, W.J.; Salcudean, M. & Wessel, R.A.
Partner: UNT Libraries Government Documents Department

Sodium and sulfur release and recapture during black liquor burning

Description: The objective of this study was to provide data on sulfur and sodium volatilization during black liquor burning, and on SO2 capture by solid sodium carbonate and sodium chloride. This data was interpreted and modeled into rate equations suitable for use in computational models for recovery boilers.
Date: August 1, 1995
Creator: Frederick, W.J.; Iisa, K.; Wag, K.; Reis, V.V.; Boonsongsup, L.; Forssen, M. et al.
Partner: UNT Libraries Government Documents Department

Control of the accumulation of non-process elements and organic compounds in pulp mills with bleach filtrate reuse. Milestones and progress, Quarter 9 (July 1--September 30, 1998)

Description: The two approach changes that were discussed and recommended in the Quarter 8 (April 1--June 30, 1998) progress report have been implemented in the current project plan. The OLI software has been used to develop a preliminary process model for predicting the distribution of NPE`s in a two stage brownstock washer, and the OLI database has been upgraded to include improved chemical equilibrium data for metal-organic interactions. This exercise served as a tool to evaluate the data and methods developed in this study, and to demonstrate its utility to industry. The Weyerhaeuser-NAELS software has also been applied to predicting inorganic solubility behavior. Task C-1.2, Estimation of unavailable thermodynamic parameters (scheduled completion date: 12/97), has been combined with Task D-2.1, Evaluation of the estimation procedure (scheduled completion date: 3/99) with a new scheduled completion date of 8/99. A model for the adsorption of metal ions on wood pulp fibers will include transport effects as well as adsorption equilibrium, and will be combined with a brownstock washer model to evaluate its predictive capability in comparison with mill data, and to demonstrate the applicability of the results obtained in this project. Three tasks are behind schedule: Task A-2.3, Measurement of stability constants for wood organics with metal ions (scheduled completion date: 6/98), Task B-2.1, Measure metal adsorption isotherms on wood pulp (scheduled completion date: 9/97), and Task B-2.3, Measure metal ion adsorption kinetics for strongly adsorbing metal species (scheduled completion date: 3/98). The reasons and expected completion dates are discussed in the Performance Variances and Open Items section. All other tasks are either completed, on, or ahead of schedule.
Date: December 31, 1998
Creator: Frederick, W.J.; Laver, M.L.; Rorrer, G.L.; Rudie, A.W. & Schmidl, W.
Partner: UNT Libraries Government Documents Department

Study of soluble scale fouling control in high solids black liquor concentrators. Progress report, quarter 5 (October 1, 1999 - December 31, 1999)

Description: During this quarter, work has finally resumed on the black liquor solubility experiments, but no new data have been generated. The crystallization experiments with inorganic model solutions have been completed, and crystallization experiments with kraft black liquor have been started. The Annular Test Cell apparatus is now fully operational, while construction of the falling film evaporator pilot plant is nearly complete. Startup of this unit is planned for late in Quarter 6. In the CFD model development work, the relaxation of simplifying assumptions in the falling film model have been completed, and expressions were developed to estimate film velocity/film Reynolds number relations. Also, thin film data taken for a range of conventional fluids were compared to predictions using selected methods, and attempts were initiated to extrapolate to approximate black liquor evaporator conditions.
Date: January 1, 2000
Creator: Frederick, W. J.; Chen, F.; Hsieh, G.; Lien, S.; Murphy, R. W.; Rousseau, R. W. et al.
Partner: UNT Libraries Government Documents Department

Study of soluble scale fouling control in high solids black liquor concentrators

Description: The quarterly project review meeting was held at IPST on August 2, 1999 and was attended by IPST, Georgia Tech, and ORNL principal investigators, members of the Industrial Advisory Group, and a U.S. DOE representative. Although steady progress is being made, this project is currently behind schedule. The specific tasks that are behind schedule, the reasons for the delays, and the expected completion dates are discussed. The remaining tasks are either on schedule, or have not been started.
Date: September 30, 1999
Creator: Frederick, W. J.; Chen, F.; Hsieh, G.; Lien, S.; Murphy, R. W. & Rousseau, R. W.
Partner: UNT Libraries Government Documents Department

Control of the accumulation of non-process elements and organic compounds in pulp mills with bleach filtrate reuse. Milestones and progress, Quarter 8 (April 1--June 30, 1998)

Description: Overall, this project is on schedule and proceeding as planned. Two approach changes are recommended. One is to rely on commercially developed software, in particular that developed by OLI Systems, Inc., and now being expanded in a collaborative effort between OLI Systems, Inc. and IPST to provide a simulation package for the pulp and paper industry and to integrate it with existing process simulation tools used by that industry. The second is the development of a detailed brownstock/bleached fiber washer model as a tool to evaluate the data and methods developed in this study, and to demonstrate its utility to industry. Both of these are discussed in more detail in the Approach Changes section of this report. Two tasks are behind schedule. They are Task A-2.3, Measurement of stability constants for wood organics with metal ions (scheduled completion date: 6/98), and Task C-1.2, Estimation of unavailable thermodynamic parameters (scheduled completion date: 12/97). The reasons and expected completion dates for these tasks are discussed in the Performance Variances and Open Items section of this report. All other tasks are either completed, or on or ahead of schedule.
Date: August 1, 1998
Creator: Frederick, W.J.; Laver, M.L.; Rorrer, G.L.; Rudie, A.W. & Schmidl, W.
Partner: UNT Libraries Government Documents Department

Control of the Accumulation of Non-Process Elements in Pulp Mills with Bleach Filtrate Reuse: A Chemical Equilibrium Approach to Predicting the Partitioning of Metals in Pulp Mill and Bleach Plant Streams

Description: The overall goal of this project was to develop fundamental, experimentally based methods for predicting the solubility or organic and inorganic matter and their interactions in recycled effluent from kraft pulp mills and bleach plants. This included: characterizing the capacity of wood pulp and dissolved organic matter to bind metal ions, developing a thermodynamic database of properties needed to describe the solubility of inorganic matter in pulp mill streams, incorporation of the database into equilibrium calculation software for predicting the solubility of the metals of interest, and evaluating its capability to predict the distribution of the metals between pulp fibers, inorganic precipitates, and solution.
Date: August 1, 2000
Creator: Frederick, W.J. Jr.; Rudie, A.W.; Schmidl, G.W.; Sinquefield, S.A.; Rorrer, G.L.; Laver, M.L. et al.
Partner: UNT Libraries Government Documents Department

Recent Measurements And Plans for the SLAC Compton X-Ray Source

Description: A compact source of monoenergetic X-rays, generated via Compton backscattering, has been developed in a collaboration between U.C Davis and SLAC. The source consists of a 5.5 cell X-band photoinjector, a 1.05 m long high gradient accelerator structure and an interaction chamber where a high power (TW), short pulse (sub-ps) infrared laser beam is brought into a nearly head-on collision with a high quality focused electron beam. Successful completion of this project will result in the capability of generating a monoenergetic X-ray beam, continuously tunable from 20 - 85 keV. We have completed a series of measurements leading up to the generation of monoenergetic X-rays. Measurements of essential electron beam parameters and the techniques used in establishing electron/photon collisions will be presented. We discuss the design of an improved interaction chamber, future electro-optic experiments using this chamber and plans for expanding the overall program to the generation of Terahertz radiation.
Date: February 14, 2006
Creator: Vlieks, A.E.; Akre, R.; Caryotakis, G.; DeStefano, C.; Frederick, W.J.; Heritage, J.P. et al.
Partner: UNT Libraries Government Documents Department