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Advanced Modeling and Materials in Kraft Pulp Mills

Description: This CRADA provided technical support to the Weyerhaeuser Company on a number of issues related to the performance and/or selection of materials at a number of locations in a pulp and paper mill. The studies related primarily to components for black liquor recovery boilers, but some effort was directed toward black liquor gasifiers and rolls for paper machines. The purpose of this CRADA was to assist Weyerhaeuser in the evaluation of materials exposed in various paper mill environments and to provide direction in the selection of alternate materials, when appropriate.
Date: May 15, 2002
Creator: Keiser, J.R. & Gorog, J.P.
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

High-solids black liquor firing in pulp and paper industry Kraft recovery boilers. Final report, Phase 1, Volume 1: Executive summary

Description: This project is a multiple-phase effort to develop technologies to improve high-solids black liquor firing in pulp mill recovery boilers. The objectives are to develop a preliminary design of a recovery furnace simulator; evaluate the economics of high-solids; and delineate a project concept for evaluating candidate technologies to improve chemical recovery.
Date: November 1, 1995
Creator: Southards, W.T.; Clement, J.L.; McIlroy, R.A.; Tharp, M.R.; Verrill, C.L. & Wessell, 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

Fundamental study of black liquor gasification kinetics using a pressurized entrained-flow reactor (PEFR). Quarterly progress report for the period July 1999 to September 1999

Description: The goal of the program is to identify the optimal operating window for black liquor gasification. The goals during this year are to prepare the PEFR for operation, conduct a series of preliminary screening tests to bracket BLG operating conditions, and develop a process model that can guide identification of the optimal operating window.
Date: October 29, 1999
Partner: UNT Libraries Government Documents Department

Thermal Behavior of Floor Tubes in a Kraft Recovery Boiler

Description: The temperatures of floor tubes in a slope-floored black liquor recovery boiler were measured using an array of thermocouples located on the tube crowns. It was found that sudden, short duration temperature increases occurred with a frequency that increased with distance from the spout wall. To determine if the temperature pulses were associated with material falling from the convective section of the boiler, the pattern of sootblower operation was recorded and compared with the pattern of temperature pulses. During the period from September, 1998, through February, 1999, it was found that more than 2/3 of the temperature pulses occurred during the time when one of the fast eight sootblowers, which are directed at the back of the screen tubes and the leading edge of the first superheater bank, was operating.
Date: September 12, 1999
Creator: Barker, R.E.; Choudhury, K.A.; Gorog, J.P.; Hall, L.M.; Keiser, J.R. & Sarma, G.B.
Partner: UNT Libraries Government Documents Department

Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer

Description: University of Utah's project entitled 'Investigation of Fuel Chemistry and Bed Performance in a Fluidized Bed Black Liquor Steam Reformer' (DOE Cooperative Agreement DE-FC26-02NT41490) was developed in response to a solicitation released by the U.S. Department of Energy in December 2001, requesting proposals for projects targeted towards black liquor/biomass gasification technology support research and development. Specifically, the solicitation was seeking projects that would provide technical support for Department of Energy supported black liquor and biomass gasification demonstration projects under development at the time.
Date: June 30, 2007
Creator: Whitty, Kevin
Partner: UNT Libraries Government Documents Department

In Situ Causticizing for Black Liquor Gasification

Description: Black liquor gasification offers a number of attractive incentives to replace Tomlinson boilers but it also leads to an increase in the causticizing load. Reasons for this have been described in previous reports (FY04 ERC, et.al.). The chemistries have also been covered but will be reviewed here briefly. Experimental results of the causticizing reactions with black liquor are presented here. Results of the modeling work were presented in detail in the Phase 1 report. They are included in Table 2 for comparison but will not be discussed in detail. The causticizing agents were added to black liquor in the ratios shown in Table 1, mixed, and then spray-dried. The mixture ratios (doping levels) reflect amount calculated from the stoichiometry above to achieve specified conversions shown in the table. The solids were sieved to 63-90 microns for use in the entrained flow reactors. The firing conditions are shown in Table 2. Pictures and descriptions of the reactors can be found in the Phase 1 annual report. Following gasification, the solids (char) was collected and analyzed by coulometric titration (for carbonate and total carbon), and by inductively coupled plasma emission spectroscopy (ICP) for a wide array of metals.
Date: October 1, 2005
Creator: Sinquefield, Scott Alan
Partner: UNT Libraries Government Documents Department

Fundamental Study of Black Liquor Gasification Kinetics. Quarterly progress report for the period October 1999 to December 1999

Description: The overall objective of this research is to evaluate the kinetics of gasification of kraft black liquor under laboratory conditions simulating pressurized, oxygen-blown gasification. The significant independent variables are gasifier temperature, black liquor composition particle size, and particle residence time. The authors will quantify their impact on the concentration of major and trace gas phase species, as well as the composition of condensed phase inorganic products, including specification of the Na- and S-containing compounds and overall carbon conversion.
Date: January 31, 2000
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

Test plan for radioactive testing of a vertical direct denitration calciner

Description: A vertical calciner will be used to demonstrate the direct denitration process for converting plutonium-bearing liquors to stable plutonium rich solids. The calciner and come of its associated equipment were previously tested with non-radioactive chemicals to demonstrate operability.
Date: July 17, 1996
Creator: Fisher, F.D., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Analysis of cracking of co-extruded recovery boiler floor tubes

Description: Cracking of the stainless steel layer in co-extruded 304L/SA210 tubing used in black liquor recovery boilers is being found in an ever-increasing number of North American pulp and paper mills. Because of the possibility of a tube failure, this is a significant safety issue, and, because of the extra time required for tube inspection and repair, this can become an economic issue as well. In a project funded by the U.S. Department of Energy and given wide support among paper companies, boiler manufacturers, and tube fabricators, studies are being conducted to determine the cause of the cracking and to identify alternate materials and/or operating procedures to prevent tube cracking. Examination of cracked tubes has permitted characterization of crack features, and transmission electron microscopy is providing information about the thermal history, particularly cyclic thermal exposures, that tubes have experienced. Neutron and x-ray diffraction techniques are being used to determine the residual stresses in as-fabricated tube panels and exposed tubes, and finite element modeling is providing information about the stresses the tubes experience during operation. Laboratory studies are being conducted to determine the susceptibility of the co-extruded 304L/SA210 tubes to stress corrosion cracking, thermal fatigue, and corrosion in molten smelt. This paper presents the current status of these studies. On the basis of all of these studies, recommendations for means to prevent tube cracking will be offered.
Date: August 1, 1997
Creator: Keiser, J.R.; Taljat, B. & Wang, X.L.
Partner: UNT Libraries Government Documents Department

High-efficiency chlorine dioxide delignification. Summary of progress, April 1--June 30, 1998

Description: The authors have been pursuing strategies for improving the efficiency of utilization and environmental performance of ClO{sub 2} in the delignification of kraft pulps. These strategies combine a pretreatment followed by ClO{sub 2} treatment under conditions selected to result in high efficiency, and a suitably altered alkaline extraction stage. In addition, a series of experiments was completed in which the authors compared the response to conventional D(EO) delignification of conventional kraft pulps and pulps from a laboratory simulation of Ahlstrom`s Lo-Solids{reg_sign} extended delignification (modified) process. These experiments were conducted over a range of kappa numbers for both pulping processes, and at high and low kappa factors. The results showed that the modified pulps were slightly easier to bleach in the conventional process, an observation which parallels the corresponding observation made earlier, when the same pulps were bleached with the Rapid D{sub 0} short-retention process. In other experiments, two sets of hardwood pulps of varied unbleached kappa number were subjected to determinations of their hexeneuronic acid contents. Pulps representing both conventional batch and extended (RDH) kraft pulping processes were included. Residual lignin and effluent structural analyses by NMR and gel permeation chromatography are continuing to generate data for the development of structure-bleachability relationships. Analysis of this data is in progress.
Date: July 31, 1998
Creator: Ragauskas, A.J. & McDonough, T.J.
Partner: UNT Libraries Government Documents Department

Improved Materials for Use as Components in Kraft Black Liquor Recovery Boilers

Description: This Cooperative Research and Development Agreement (CRADA) was undertaken to evaluate current and improved materials and materials processing conditions for use as components in kraft black liquor recovery boilers and other unit processes. The main areas addressed were: (1) Improved Black Liquor Nozzles, (2) Weld Overlay of Composite Floor Tubes, and (3) Materials for Lime Kilns. Iron aluminide was evaluated as an alternate material for the nozzles used to inject an aqueous solution known as black liquor into recovery boilers as well for the uncooled lining in the ports used for the nozzles. Although iron aluminide is known to have much better sulfidation resistance in gases than low alloy and stainless steels, it did not perform adequately in the environment where it came into contact with molten carbonate, sulfide and sulfate salts. Weld overlaying carbon steel tubes with a layer of stainless weld metal was a proposed method of extending the life of recovery boiler floor tubes that have experienced considerable fireside corrosion. After exposure under service conditions, sections of weld overlaid floor tubes were removed from a boiler floor and examined metallographically. Examination results indicated satisfactory performance of the tubes. Refractory-lined lime kilns are a critical component of the recovery process in kraft pulp mills, and the integrity of the lining is essential to the successful operation of the kiln. A modeling study was performed to determine the cause of, and possible solutions for, the repeated loss of the refractory lining from the cooled end of a particular kiln. The evaluation showed that the temperature, the brick shape and the coefficient of friction between the bricks were the most important parameters influencing the behavior of the refractory lining.
Date: October 22, 2001
Creator: Keiser, J.R.
Partner: UNT Libraries Government Documents Department

High-solids black liquor firing in pulp and paper industry kraft recovery boilers: Phase Ia - Low-temperature gasifier evaluation. Final report, November 1, 1995--October 31, 1996

Description: This project, conducted under The United States Department of Energy (DOE) Cooperative Agreement DE-FC36-94GO10002/A002, was part of a multiple-phase effort to develop technologies that improve the energy efficiency and economics of chemical process recovery in the pulp and paper industry. The approach taken was to consider two major alternatives in two phases. Phase I, conducted previously, considered means to improve pulp mill recovery boilers using high-solids advanced combustion of black liquor; while this project, Phase la, considered means to recover kraft pulping mill process chemicals by low-temperature black liquor gasification. The principal steps previously proposed in this program were: (1) Evaluate these two technologies, high-solids advanced combustion and gasification, and then select a path forward using the more promising of these two options for future work. (2) Design and construct a pilot-scale unit based on the selected technology, and using that unit, develop the precompetitive data necessary to make commercialization attractive. (3) Develop and deploy a first-of-a-kind (FOAK) commercial unit in a kraft pulp mill. Phase I, which evaluated the high-solids advanced combustion option, was concluded in 1995. Results of that project phase were reported previously. This report describes the work conducted in Phase Ia. The work is described in Sections 1 through 4 and six appendices provide additional detail.
Date: June 1, 1997
Creator: Southards, W.T.; Blude, J.D. & Dickinson, J.A.
Partner: UNT Libraries Government Documents Department

Engineering Study for a Full Scale Demonstration of Steam Reforming Black Liquor Gasification at Georgia-Pacific's Mill in Big Island, Virginia

Description: Georgia-Pacific Corporation performed an engineering study to determine the feasibility of installing a full-scale demonstration project of steam reforming black liquor chemical recovery at Georgia-Pacific's mill in Big Island, Virginia. The technology considered was the Pulse Enhanced Steam Reforming technology that was developed and patented by Manufacturing and Technology Conversion, International (MTCI) and is currently licensed to StoneChem, Inc., for use in North America. Pilot studies of steam reforming have been carried out on a 25-ton per day reformer at Inland Container's Ontario, California mill and on a 50-ton per day unit at Weyerhaeuser's New Bern, North Carolina mill.
Date: March 19, 2002
Creator: de Carrera, Robert & Ohl, Mike
Partner: UNT Libraries Government Documents Department

Magnet options for sensors for the pulp and paper industry

Description: The Lawrence Berkeley National Laboratory (LBNL) has been developing sensors for the pulp and paper industry that uses a magnetic field. The applications for magnetic sensors that have studied include (1) sensors for the measurement of the water and ice content of wood chips entering the pulping mill, (2) sensors for measuring the water content and other constituents of the black liquor leaving the paper digester, and (3) sensors for measuring paper thickness and water content as the paper is being processed. These tasks can be done using nuclear magnetic resonance (NMR). The magnetic field used for doing the NMR can come from either permanent magnets or superconducting magnets. The choice of the magnet is dependent on a number of factors, which include the size of the sample and field strength needed to do the sensing task at hand. This paper describes some superconducting magnet options that can be used in the pulp and paper industry.
Date: May 5, 2001
Creator: Green, M.A.; Barale, P.J.; Fong, C.G.; Luft, P.A.; Reimer, J.A. & Yahnke, M.S.
Partner: UNT Libraries Government Documents Department

Investigation of Pressurized Entrained-Flow Kraft Black Liquor Gasification in an Industrially Relevant Environment

Description: The University of Utah's project 'Investigation of Pressurized Entrained-Flow Kraft Black Liquor Gasification in an Industrially Relevant Environment' (U.S. DOE Cooperative Agreement DE-FC26-04NT42261) was a response to U.S. DOE/NETL solicitation DE-PS36-04GO94002, 'Biomass Research and Development Initiative' Topical Area 4-Kraft Black Liquor Gasification. The project began September 30, 2004. The objective of the project was to improve the understanding of black liquor conversion in high pressure, high temperature reactors that gasify liquor through partial oxidation with either air or oxygen. The physical and chemical characteristics of both the gas and condensed phase were to be studied over the entire range of liquor conversion, and the rates and mechanisms of processes responsible for converting the liquor to its final smelt and syngas products were to be investigated. This would be accomplished by combining fundamental, lab-scale experiments with measurements taken using a new semi-pilot scale pressurized entrained-flow gasifier. As a result of insufficient availability of funds and changes in priority within the Office of Biomass Programs of the U.S. Department of Energy, the research program was terminated in its second year. In total, only half of the budgeted funding was made available for the program, and most of this was used during the first year for construction of the experimental systems to be used in the program. This had a severe impact on the program. As a consequence, most of the planned research was unable to be performed. Only studies that relied on computational modeling or existing experimental facilities started early enough to deliver useful results by the time to program was terminated Over the course of the program, small scale (approx. 1 ton/day) entrained-flow gasifier was designed and installed at the University of Utah's off-campus Industrial Combustion and Gasification Research Facility. The system is designed to operate at pressures as high as ...
Date: June 30, 2008
Creator: Whitty, Kevin
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: March 30, 2004
Creator: Headrick, William L.; Karakus, Musa & Rezaie, Alireza
Partner: UNT Libraries Government Documents Department

Refractory for Black Liquor Gasifiers

Description: The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective surfaces in-situ; are functionally-graded to give the best combination of thermal, mechanical, and physical properties and chemical stability; or are relatively inexpensive, reliable repair materials. Material development will be divided ...
Date: March 31, 2003
Creator: Moore, Robert E.; Headrick, William L. & Rezaie, Alireza
Partner: UNT Libraries Government Documents Department

Demonstration of Black Liquor Gasification at Big Island

Description: This Technical Progress Report provides an account of the status of the project for the demonstration of Black Liquor Gasification at Georgia-Pacific Corporation's Big Island, VA facility. The report also includes budget information and a milestone schedule. The project to be conducted by G-P is a comprehensive, complete commercial-scale demonstration that is divided into two phases. Phase I is the validation of the project scope and cost estimate. Phase II is project execution, data acquisition and reporting, and consists of procurement of major equipment, construction and start-up of the new system. Phase II also includes operation of the system for a period of time to demonstrate the safe operation and full integration of the energy and chemical recovery systems in a commercial environment. The objective of Phase I is to validate the process design and to engineer viable solutions to any technology gaps. This phase includes engineering and planning for the integration of the full-scale MTCI/StoneChem PulseEnhanced{trademark} black liquor steam-reformer chemical recovery system into G-P's operating pulp and paper mill at Big Island, Virginia. During this phase, the scope and cost estimate will be finalized to confirm the cost of the project and its integration into the existing system at the mill. The objective of Phase II of the project is the successful and safe completion of the engineering, construction and functional operation of the fully integrated full-scale steam reformer process system. This phase includes installation of all associated support systems and equipment required for the enhanced recovery of both energy and chemicals from all of the black liquor generated from the pulping process at the Big Island Mill. The objective also includes operation of the steam reformer system to demonstrate the ability of the system to operate reliably and achieve designed levels of energy and chemical recovery while maintaining ...
Date: October 20, 2003
Creator: DeCarrera, Robert
Partner: UNT Libraries Government Documents Department