Boiler Materials for Ultrasupercritical Coal Power Plants

Boiler Materials for Ultrasupercritical Coal Power Plants 1015693 DOE Award No.: DE-FG26-01NT41175 Ohio Coal Development Office (OCDO) Grant Number: D-05-02(A) Boiler Materials for Ultrasupercritical Coal Power Plants 1015693 Technical Update, March 2009 Reporting Period Start Date: January 1, 2008 Reporting Period End Date: December 31, 2008 EPRI Project Manager R Viswanathan Electric Power Research Institute (EPRI) Cosponsors U.S Department of Energy Ohio Coal Development Office Contributors J Shingledecker, Oak Ridge National Laboratory (ORNL) M Santella, Oak Ridge National Laboratory (ORNL) J Sarver, Babcock & Wilcox Company M Gagliano, Foster Wheeler Corporation M Borden, Alstom Power, Incorporated W Mohn, Babcock & Wilcox Company J Sanders, Babcock & Wilcox Company S Goodstine Astom Power, Incorporated B Vitalis, Riley Power, Incorporated T Totemeier, Alstom Power, Incorporated Project Director R Purgert Energy Industries of Ohio Issued: 12/31/08 DOE Award No.: DE-FG26-01NT41175 OCDO Grant Number: D-05-02(A) ELECTRIC POWER RESEARCH INSTITUTE 3420 Hillview Avenue, Palo Alto, California 94304-1338 ▪ PO Box 10412, Palo Alto, California 94303-0813 ▪ USA 800.313.3774 ▪ 650.855.2121 ▪ askepri@epri.com ▪ www.epri.com U.S Department of Energy Disclaimer THIS REPORT WAS PREPARED AS AN ACCOUNT OF WORK SPONSORED BY AN AGENCY OF THE UNITED STATES GOVERNMENT NEITHER THE UNITED STATES GOVERNMENT NOR ANY AGENCY THEREOF, NOR ANY OF THEIR EMPLOYEES, MAKES ANY WARRANTY, EXPRESS OR IMPLIED, OR ASSUMES ANY LEGAL LIABILITY OR RESPONSIBILITY FOR THE ACCURACY, COMPLETENESS, OR USEFULNESS OF ANY INFORMATION, APPARATUS, PRODUCT, OR PROCESS DISCLOSED, OR REPRESENTS THAT ITS USE WOULD NOT IINFRINGE PRIVATELY OWNED RIGHTS REFERENCE HEREIN TO ANY SPECIFIC COMMERCIAL PRODUCT, PROCESS, OR SERVICE BY TRADE NAME, TRADEMARK, MANUFACTURER, OR OTHERWISE DOES NOT NECESSARILY CONSTITUTE OR IMPLY ITS ENDORSEMENT, RECOMMENDATION, OR FAVORING BY THE UNITED STATES GOVERNMENT OR ANY AGENCY THEREOF THE VIEWS AND OPINIONS OF AUTHORS EXPRESSED HEREIN DO NOT NECESSARILY STATE OR REFLECT THOSE OF THE UNITED STATES GOVERNMENT OR ANY AGENCY THEREOF Legal Notice/Disclaimer This report was prepared by the Energy Industries of Ohio in consortium with the Electric Power Research Institute, Inc (EPRI); ALSTOM Power, Inc.; Riley Power, Inc.; Babcock & Wilcox/McDermott Technology, Inc.; and Foster Wheeler Development Corporation pursuant to a Grant partially funded by the U.S Department of Energy (DOE) under Instrument Number DE-FG26-01NT41175 and the Ohio Coal Development Office/Ohio Air Quality Development Authority (OCDO/OAQDA) under Grant Agreement Number D-05-02(A) NO WARRENTY OR REPRESENTATION, EXPRESS OR IMPLIED, IS MADE WITH RESPECT TO THE ACCURACY, COMPLETENESS, AND/OR USEFULNESS OF INFORMATION CONTAINED IN THIS REPORT FURTHER, NO WARRANTY OR REPRESENTATION, EXPRESS OR IMPLIED, IS MADE THAT THE USE OF ANY INFORMATION, APPARATUS, METHOD, OR PROCESS DISCLOSED IN THIS REPORT WILL NOT INFRINGE UPON PRIVATELY OWNED RIGHTS FINALLY, NO LIABILITY IS ASSUMED WITH RESPECT TO THE USE OF, OR FOR DAMAGES RESULTING FROM THE USE OF, ANY INFORMATION, APPARATUS, METHOD OR PROCESS DISCLOSED IN THIS REPORT Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the Department of Energy and/or the State of Ohio; nor the views and opinions of authors expressed herein necessarily state or reflect those of said government entities NOTICE TO JOURNALISTS AND PUBLISHERS: Please feel free to quote and borrow from this report, however, please include a statement noting that the U.S Department of Energy and the Ohio Coal Development Office provided support for this project DISCLAIMER OF WARRANTIES AND LIMITATION OF LIABILITIES THIS DOCUMENT WAS PREPARED BY THE ORGANIZATION(S) NAMED BELOW AS AN ACCOUNT OF WORK SPONSORED OR COSPONSORED BY THE ELECTRIC POWER RESEARCH INSTITUTE, INC (EPRI) NEITHER EPRI, ANY MEMBER OF EPRI, ANY COSPONSOR, THE ORGANIZATION(S) BELOW, NOR ANY PERSON ACTING ON BEHALF OF ANY OF THEM: (A) MAKES ANY WARRANTY OR REPRESENTATION WHATSOEVER, EXPRESS OR IMPLIED, (I) WITH RESPECT TO THE USE OF ANY INFORMATION, APPARATUS, METHOD, PROCESS, OR SIMILAR ITEM DISCLOSED IN THIS DOCUMENT, INCLUDING MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, OR (II) THAT SUCH USE DOES NOT INFRINGE ON OR INTERFERE WITH PRIVATELY OWNED RIGHTS, INCLUDING ANY PARTY'S INTELLECTUAL PROPERTY, OR (III) THAT THIS DOCUMENT IS SUITABLE TO ANY PARTICULAR USER'S CIRCUMSTANCE; OR (B) ASSUMES RESPONSIBILITY FOR ANY DAMAGES OR OTHER LIABILITY WHATSOEVER (INCLUDING ANY CONSEQUENTIAL DAMAGES, EVEN IF EPRI OR ANY EPRI REPRESENTATIVE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES) RESULTING FROM YOUR SELECTION OR USE OF THIS DOCUMENT OR ANY INFORMATION, APPARATUS, METHOD, PROCESS, OR SIMILAR ITEM DISCLOSED IN THIS DOCUMENT ORGANIZATION(S) THAT PREPARED THIS DOCUMENT Electric Power Research Institute (EPRI) U.S Department of Energy (DOE) Energy Industries of Ohio This is an EPRI Technical Update report A Technical Update report is intended as an informal report of continuing research, a meeting, or a topical study It is not a final EPRI technical report This material is based upon work supported by the Department of Energy under Award Number DE-FG26-01NT41175 This document describes research sponsored by the U.S Department of Energy (DOE) and the Ohio Coal Development Office (OCDO), and technically managed by the Electric Power Research Institute (EPRI) NOTE For further information about EPRI, call the EPRI Customer Assistance Center at 800.313.3774 or e-mail askepri@epri.com Electric Power Research Institute, EPRI, and TOGETHER…SHAPING THE FUTURE OF ELECTRICITY are registered service marks of the Electric Power Research Institute, Inc Copyright © 2009 Electric Power Research Institute, Inc All rights reserved CITATIONS This document was prepared by Electric Power Research Institute (EPRI) 3420 Hillview Ave Palo Alto, CA 94304 Principal Investigator R Viswanathan Energy Industries of Ohio Park Center Plaza, Suite 200 6100 Oak Tree Blvd Independence, OH 44131 Principal Investigator R Purgert This document describes research sponsored by the U.S Department of Energy (DOE) and the Ohio Coal Development Office (OCDO), and technically managed by the Electric Power Research Institute (EPRI) The technical tasks were performed by the organizations listed as contributors This publication is a corporate document that should be cited in the literature in the following manner: Boiler Materials for Ultrasupercritical Coal Power Plants EPRI, Palo Alto, CA, USDOE, Washington, D.C., and OCDO, Columbus, OH: 2009 1015693 iii PRODUCT DESCRIPTION A major, 5-year, national effort is being sponsored by the Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) to develop/evaluate materials for advanced ultrasupercritical (AUSC) boilers capable of operating with steam up to 760ºC (1400ºF), 35 MPa (5000 psia) This work is being carried out by a consortium comprised of Energy Industries of Ohio (EIO), EPRI, Oak Ridge National Laboratory (ORNL), and all domestic boiler manufacturers The scope of the materials evaluation includes mechanical properties, steam-side oxidation and fireside corrosion studies, weldability and fabricability evaluations, and review of applicable design codes and standards Phase of these evaluations is now complete, and the results have given the industry greater confidence that currently available materials can meet the challenge In Phase of the program, the tasks defined in Phase have been extended to finish and enhance Phase activities In addition, preliminary work has been started to model an oxyfuel boiler to define the local environments expected to occur and to study corrosion behavior of alloys This is a status report on the project Individual reports specific to several tasks have been issued previously This Technical Update covers work performed between January and September 2008 It describes worked performed under Tasks 2-4 There was no reportable progress under Task and Tasks 5-8 during this time period Results and Findings The materials and processes required for successful operation at steam temperatures approaching 1400ºF (760°C) have been identified Challenges and Objective(s) The objective of this project is to develop materials technologies that allow use of advanced steam cycles in coal-based power plants These advanced cycles, with target steam temperatures up to 1400°F (760°C), will increase the efficiency of coal-fired boilers and reduce emissions substantially In addition to a reduction in all fuel-related emissions, there are additional benefits to higher efficiency that favorably impact carbon management Applications, Values, and Use st In the 21 Century, the world faces the critical challenge of providing abundant, cheap electricity to meet the needs of a growing global population while, at the same time, preserving the environment Most studies of this issue conclude that a robust portfolio of generation technologies and fuels should be developed to assure that the United States will have adequate electricity supplies in a variety of possible future scenarios Traditional methods of coal combustion emit pollutants, including CO2, at high levels relative to other generation options Maintaining coal as a generation option will require methods for addressing these environmental issues The USC boiler is a key component of advanced steam cycles with the potential to increase efficiency and reduce emissions EPRI Perspective When Phase is completed, this project will enable selection of appropriate alloys and coatings required for economical construction and operation of coal-fired power plants capable of v operating under USC steam conditions and using coals containing different levels of sulfur Optimum methods for fabricating and welding of these alloys will become available The cycling studies performed here will enable optimization of operational and maintenance practices in power plants Based on the knowledge of the creep strength and corrosion rates of alloys, appropriate inspection intervals can be defined and the remaining life of operating components can be estimated Most importantly, the technology developed in this project will enable construction of very high efficiency USC plants with reduced emissions Phase will explore the potential for combining USC technology with oxy-fuel combustion technology It is hoped that this will be a major step towards reducing and capturing CO2 emissions Approach The project team summarized results of the tasks of Phase of the Boiler Materials for Ultrasupercritical Coal Power Plants project Keywords Ultrasupercritical boilers Boiler materials Materials technology Advanced steam cycles vi ABSTRACT The U.S Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than the current generation of supercritical plants This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC) A limiting factor in this can be the materials of construction The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760°C (1400°F)/35 MPa (5000 psi) This goal seems achievable based on a preliminary assessment of material capabilities The project is intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620°C (1150°F) and nickel-based alloys suitable up to 700°C (1300°F) In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler A major effort involving tasks was recently completed in phase In this phase 2, the earlier defined tasks have been extended to finish and enhance the phase activities In addition, preliminary work has been undertaken to model an oxy-fuel boiler to define local environments expected to occur and to study corrosion behavior of alloys under these conditions This report provides a yearly status report for the period of January–September, 2008 vii COMPANY-WISE PROGRESS 3.1 Contract Extension (ALSTOM) 3.1.1 Objective for Contract Extension: • Permit Alstom to perform work directed at achieving the Statement of Project Objectives of the renewed Federal Grant These objectives will be accomplished through execution of eight tasks as follows: • • • • • • • • Task 1: Conceptual Design and Economic Analysis Task 4E: Steam Loop Corrosion Testing Task 4F: Fundamentals of Oxy-firing Combustion Gas Chemistry Task 4G: Coal-Ash Corrosion/Carburization Task 6D: Fabricable Waterwalls Task 8E: Dynamic Boiler Response and Cycling Capabilities Task 8F: Design Guidelines and Assessment Procedures for Welded Components Task 8G: Component Durability Verification Facility Funding availability resulted in a restructuring of the scheduled task activities As part of the restructuring, Alstom will for the near term concentrate on Task 4E: Steam Loop Corrosion Testing Progress achieved during this reporting period is presented in the following narrative 3.1.2 Task 4E: Steam Loop Corrosion Testing (ALSTOM) Objective: • Evaluate the corrosion and steam oxidation performance of candidate USC boiler materials in a realistic, coal-fired exposure environment 3-1 Progress for the Quarter: • • Discussions continue with Site A The utility continues to express a desire to participate but has raised additional questions A presentation is scheduled in early February at the corporate offices to provide additional information on the technical details of the proposed testing The utility wants to understand the technical details in order to assess their risks in accepting a level of liability They understand that this is an R&D program that cannot guarantee problem-free operation and are willing to proceed if the risk is judged low enough Progress toward agreement on a Host Site Agreement for Site B continued but resolution was not achieved Based on the timing of the unit outage, insufficient time remained to accomplish an installation at Site B As a result, Site B is no longer being considered for hosting a steam loop Concerns: • Site selection and execution of agreement to proceed in time to meet outage requirements Plans for the Next Quarter: • 3.2 Continue negotiations for Steam Loop host site selection at Site A Task - Steamside Oxidation (B&W) 3.2.1 Task 3A - Autoclave Testing Background • Steamside oxidation (STOX) tests will be performed on commercially available and developmental materials at temperatures between 650°C and 800°C (1202°F 1472°F) Experimental The second STOX exposure at 750°C (1,000 hours) was completed in mid-September The third STOX exposure at 750°C (2,000 hours) was started in mid-October The descaled weight loss data from the first 750°C exposure were used to develop parabolic rate constants Weight change data from the second exposure period at 750°C were also used to calculate kp values Plots of kp vs temperature were constructed for all materials that had been previously tested at other temperatures Work is continuing on descaling the specimens removed following the second 750°C exposure and evaluating tested specimens with SEM/EDS 3-2 Concerns • None Activities Next Quarter • The third exposure period at 750°C will conclude and all the specimens will be weighed and evaluated with SEM/EDS 3.2.2 Task 3D - Review of Available Information & Reporting Background • Available steamside oxidation literature pertaining to materials and environmental conditions of interest will be reviewed Project status updates will be prepared and status meetings will be attended as required Experimental • A presentation on Task results was made at the USC Materials Steering Committee Meeting in Chicago in November, 2008 Concerns • None Activities Next Quarter • A draft of the final report will be written by the end of March, 2009 3.2.3 Task 3H - Steamside Exfoliation Evaluation Background • Testing will be performed on boiler tube sections to evaluate the impact of material variables (e.g., tube geometry, alloying elements, surface condition) and operational variables (e.g., temperature, pressure, steam composition, heat-up/cool-down rates) on the steamside exfoliation (STEX) behavior of boiler materials Experimental • Preliminary trials on the STEX acoustic emission (AE) equipment continued last quarter Concerns • None Activities Next Quarter • Construction of the test facility and test technique development will continue 3-3 3.3 Task – Welding (B&W) Activities This Quarter • • Special Metals has produced heats of Inconel 740 for use in evaluating thick plate welds with the revised chemistry for microfissuring resistance during the previous quarter The plates were delivered to B&W and machined for welding We are awaiting the delivery of the weld wire conforming to the optimized chemistry for producing crack free welds Welds will be performed as soon as the wire is delivered which is projected for January of 2009 More thick plate welding of Haynes 282 was initiated Problems Encountered This Quarter • None Activities for Next Quarter • • 3.4 • • • • Thick plate welds will be produced on Inconel 740 of the final chemistry which eliminates microfissuring More Haynes 282 plates to be welded and evaluated to ASME Section IX criteria Task - Fabrication (B&W) The objective of Task has been to establish boiler fabrication guidelines for the high temperature, oxidation and corrosion resistant alloys selected for the USC Project The principal goals in this joint effort are: To establish fabrication guidelines for the high temperature, corrosion resistant alloys needed for boiler components in the USC power plant To determine the thermomechanical treatments or other remedial actions necessary to restore material properties which might degrade due to fabrication operations To investigate prototypical manufacturing operations for producing both thick wall and thin wall components from the USC alloys Progress for the Quarter (Riley Power, Inc.) • Task is complete Concerns: • None Plans for the Next Quarter: • None Task is complete Progress for the Quarter: (Alstom Power, Inc.) • Task is complete 3-4 Concerns: • None Plans for the Next Quarter: • None Task is complete Progress for the Quarter: (B&W) • Task is complete Concerns: • None Plans for the Next Quarter: • None Task is complete Progress for the Quarter: (Foster Wheeler) • Preparation of FW’s addendum to the Task topical report continued Concerns: • None Goals for the Next Quarter: • • 3.5 Complete preparation of the FW contribution to the Task Topical Report which will be issued as an addendum Complete four subtask reports summarizing the results of the controlled strain/recrystallization/precipitation studies for HR6W, SAVE12, and alloy 230, work which was subcontracted to FW by Riley Power and B&W, and the FW report for alloy 740 – all together to be issued as part of the addendum to the Task Topical Report Task - Fireside Corrosion (Foster Wheeler) Objective The objective of the task is to evaluate the relative resistance of various advanced alloys for waterwall and reheater/superheater construction to fireside corrosion over the full temperature range expected for the USC plant The corrosive environment promoted by three different coals, representative of an eastern coal, a midwestern coal, and a western coal, will be evaluated 3-5 3.5.1 Task 4A - Laboratory Testing Objective The objective of this sub-task is to perform laboratory corrosion tests on the candidate alloys This will be accomplished by exposing metal coupons to various deposits and flue gases representative of three coals (e.g., eastern, midwestern, and western) at the range of temperatures expected for the USC plant Concerns • None Plans for Next Quarter • Task completed 3.5.2 Task 4B - Corrosion Probe Testing in Utility Boilers Objective The objective of this sub-task is to install corrosion probes comprised of various alloys/coatings/weld overlays at three coal-fired power plants and control them in the temperature range expected for reheater/superheater components in the USC plant The plants should burn coals representative of the three types specified earlier At the end of the testing, the corrosion probes will be removed and material specimens will be evaluated for corrosion resistance Experimental Progress • • • • 3.6 Continued monitoring and maintenance of the two-year probe at Xcel Energy – Pawnee Station (Western coal host site) The two-year probe has been exposed to service temperatures for over 17,000 hours and is expected to be removed within Q1 2009 The evaluation of the one-year probe is complete, but the analysis of the corrosion data is ongoing Continued monitoring and maintenance of the one and two-year probes AEP’s Gavin Station In September 2008, the 2-year probe that was installed at Duke Energy – Gibson Station was removed from service after a short time overheating event The probe is currently being analyzed, while the evaluation of the one-year probe is complete, but the analysis of the corrosion data is still on-going Oxy-combustion add-on work Task – Mechanical Properties (ORNL) Background There are two broad objectives for Task 2.The first is to produce the mechanical properties database needed to design a boiler to operate at steam conditions up to 760°C This requires: producing long-term creep data, assessing creep-fatigue interactions, evaluating the properties of 3-6 both deposited weld metal and welded joints, and performing structural feature tests to validate/develop improved materials and component models A second object is to understand the complex interactions between the processing, properties, and performance of the candidate alloys to provide a firm foundation for the necessary materials technology developments Critical aspects of this include understanding the effects of microstructure on long-term behavior, determining the effects of processing variables like coldwork on long-term component performance, and assessing, from the perspective of long-term material and component behavior, whether a candidate alloy/fabrication/joining process will meet the requirements of the program The ORNL Task work scope is jointly determined by ORNL and the consortium, and given in ORNL’s field work proposal (FWP) which is funded directly by DOE Progress - Long-term Creep Strength Long-term creep testing continued on base metal specimens of several alloys including Super 304H, CCA617, and Inconel 740 The estimated durations of these tests are mainly in the timeframe of 10,000-45,000 hours A smaller number of shorter duration tests are also continuing The only Super 304H specimen has accumulated 49,176 hours of an estimated life of 100,000 hours These tests are critical because the operating conditions of USC systems will require incorporation alloys that either are new or not traditionally used in the designs of utility boilers In addition, ASME B&PV Code requirements are considering discounting short-term data in favor of longer-term 10,000 to 30,000 hours testing The majority of the base-metal creep-rupture testing focused on Inconel 740 This is because Inconel 740 appears to be the only alloy with the combination fabricability and strength to withstand the 760°C service conditions The goal of the testing is to produce the time-dependent data required for approval of Inconel 740 under an ASME B&PV Code Case ORNL is currently testing two commercially-produced heats which includes two solution heat-treatments, two aging conditions, and three product forms A third commercially-produced heat (Hv1220) was recently received Creep test specimens were machined from heat and they are being prepared for testing Welds and Welded Joints A critical issue in weldment testing is the extent to which base metal strength levels are preserved This characteristic of weldments is represented by the Weld Strength Factor (WSF) For fixed rupture time and temperature, the Weld Strength Factor is the ratio of the rupture stress of a weld joint to that of base metal A Weld Strength Factor of is ideal; in that case, critical welded components can be designed to base metal limits When the Weld Strength Factor is less than 1, design stresses must be limited to lower levels than base metal could otherwise support Both characterizing and minimizing Weld Strength Factors are important to achieving optimum use of alloys Consequently, cross-weld creep-rupture testing is a key element of this Task The largest portion of the current testing is focused on evaluating the long-term cross-weld creep-rupture strength of tube butt welds of Inconel 740, CCA617, Haynes 230, and thick-plate CCA617 (SMAW and SAW process) Tests on thicker plate Haynes 230 welds and Inconel 740 are planned but they depend on material availability and resource levels 3-7 Limited large, full-size specimens, and corresponding ~1/3 thickness specimens are being tested concurrently on CCA617 to (a) determine the effects of weld process/chemistry on creep behavior; (b) determine if there is any change in failure mode in the weldment with testing time; and, (c) to evaluate the effect of restraint (geometry) on the behavior of these welds Processing Variables A set of pressurized creep tests (775°C-5,600 psi) on cold-bent boiler tubes of CCA617 are approaching 6000 hours The results of this study will be compared to the results on Haynes 230 to set rational cold-strain limits for solid solution strengthened nickel-based alloys To verify recrystallization models proposed by Task 6, remaining cold-strained tapered tubes of all candidate alloys were provided to ORNL for long-term (>10,000 hours) aging Materials were sectioned and labeled this quarter and exposures will begin next quarter for CCA617, Haynes 230, Inconel 740, and Super 304H These tests will provide valuable long-term recrystallization data at service relevant temperatures and times This will aid in evaluating the tube-bend tests as well as add confidence to the task models based on data to ~1,000 hours Concerns • Testing plans are being curtailed based on reduced funding levels Plans for Next Quarter • 3.7 Continue all current testing including base metal, weldments, and tube bends Initial tests of the third 740 heat will be available Specimen preparation for a cold-work study will begin Task – Steamside Oxidation (ORNL) Progress Exposures in the steam rigs at 600°C (1112°F) and at 750°C (1382°F) have continued, with both rigs having completed 3.5kh out of the planned 4kh In an attempt to maximize the usefulness of the data generated in light of current program constraints, some changes in the planned effort have been made While metallographic preparation has been almost completed for specimens exposed for and 2kh, the 3kh specimens will not be examined metallographically Instead, the specimens originally targeted for removal at 3kh are continuing in the tests to provide additional mass change data points At the end of 4kh, these specimens will be stored in the event that it becomes possible to extend their exposure times at a later date The impact of this change is that microstructural data from these runs will be generated for exposures of 1, 2, and 4kh The runs at 600°C continue to produce mass-change data that are self consistent, but significantly lower than expected from comparison with data generated in this program at other temperatures, and from literate data By contrast, the oxidation rates measured at 750°C agree very well with the rates expected The 600°C runs are the first to be made in an essentially identical test rig to that used for exposures at other temperatures, including the 750°C runs, but detailed examination of the rig and the operating parameters has revealed no obvious source of discrepancy As indicated in the previous report, there are differences among the morphologies of the scales formed on some alloys at 600°C and 650°C (and among those formed at bar and 3-8 17 bar at 600°C) that may provide clues to the differences in oxidation rates Plans for conducting the required detailed analyses will be implemented as funding becomes available Concerns • The strategy imposed by the current constraints associated with operation under a Continuing Resolution has been to focus on completing the exposure runs and generating mass-change data, while postponing until funding is available metallographic examination and the detailed characterization needed to provide the basis for understanding the oxidation behavior (and differences among alloys and temperatures) While this strategy provides some level of kinetics input for addition to the overall database for the USC Steam program, delay of the analytical work jeopardizes the ability to have those contributions ready for inclusion in the final report Plans for Next Quarter • 3.8 The test exposures at 600°C and 750°C will be run to 4kh and stopped, and the mass gainbased kinetic data will be derived and reported Metallographic preparation and analysis of the specimens will be progressed at a rate depending on funding availability, and preparations will be made for the detailed analysis of selected specimens to extract information needed for mechanistic interpretation of the observed oxidation behavior Task and (Riley Power) 3.8.1 Task 1A – Conceptual Design of Oxy-Combustion Steam Generator Objective: • To extend the Task efforts of the USC materials program to the oxy-combustion application by developing a conceptual steam generator design and to identify the unique operating conditions and requirements for material properties (temperature, composition, corrosion potential) Activities This Quarter • None Concerns: • None Activities for Next Quarter: • Begin preliminary planning and research Activities will begin in mid 2009 3-9 3.8.2 Task 4D – Cold-end Oxy-comb Corrosion Studies (Riley Power Inc.) Objective: • Outline considerations for oxy-combustion steam generator and flue gas process design regarding their consequences on corrosion potential at the tail-end flue gas and CO2 compression and condensation equipment Activities This Quarter • None Concerns: • None Activities for Next Quarter: • • • None planned This task is scheduled for 2011 The drop tube furnace has arrived in Livingston NJ and is currently being set-up CFD modeling of the gas compositions within a boiler during oxy-combustion is has begun Preliminary results will be forwarded as they become available Concerns • The long delay for the installation of the last set of corrosion probes In order for the corrosion probes to be exposed for up to two-years (~17,000 hours), evaluated, analyzed and documented in a topical report before the program ends, the host site boiler must operate almost continuously Plans for Next Quarter • • • • • Continue data analysis of the one year probes that were previously removed from the Midwestern and Western utilities A more detailed examination of the operational conditions, specifically within the heat recovery areas of these host boilers is also anticipated in order to gain a better understanding of how such conditions are influencing the seemingly contradictory corrosion behavior of the probes Evaluate the two-year probe that was recently removed from the Midwestern site, and commence analysis of the of the two-year probe that is currently installed at the Western site Continue monitoring the one-year and two-year probes that were recently installed at the Eastern host site Finish set-up and calibration of the drop tube furnace Continue with CFD modeling of the boiler gas composition under oxy-fired conditions 3-10 3.8.3 Task 4C - Steam Loop Design, Construction, and Testing Objectives The objectives of this sub-task are to design, build, and test experimental USC steam loops that will operate in a commercial boiler at metal temperatures up to 1400ºF The elements of this subtask include the following: • • • Design and construct two test loops using commercially-available, high-temperature corrosion-resistant alloys selected for the USC Plant Install and operate the test loops at the Reliant Electric power plant, which is located in Niles, OH and is burning high sulfur Ohio coal Test and monitor the relative performance of the USC tube alloys, coatings, claddings, and weld overlays, which comprise the test loops, for a period of 18 to 24 months Experimental Progress • • All evaluation and analysis is complete The Topical Report has been submitted for internal review at B&W - Results of the analysis indicate that alloy 740 is most resistant to high sulfur coal ash corrosion and corrosion resistance generally increases with increasing chromium content - Alloy 72 is the most resistant of the weld overlay material, but with a nominal thickness of 0.070” its service life is expected to be about years 3-11 The Electric Power Research Institute Inc., (EPRI, www.epri.com) conducts research and development relating to the generation, delivery and use of electricity for the benefit of the public An independent, nonprofit organization, EPRI brings together its scientists and engineers as well as experts from academia and industry to help address challenges in electricity, including reliability, efficiency, health, safety and the environment EPRI also provides technology, policy and economic analyses to drive long-range research and development planning, and supports research in emerging technologies EPRI’s members represent more than 90 percent of the electricity generated and delivered in the United States, and international participation extends to 40 countries EPRI’s principal offices and laboratories are located in Palo Alto, Calif.; Charlotte, N.C.; Knoxville, Tenn.; and Lenox, Mass Together…Shaping the Future of Electricity © 2009 Electric Power Research Institute (EPRI), Inc All rights reserved Electric Power Research Institute, EPRI, and TOGETHER…SHAPING THE FUTURE OF ELECTRICITY are registered service marks of the Electric Power Research Institute, Inc Printed on recycled paper in the United States of America Electric Power Research Institute 3420 Hillview Avenue, Palo Alto, California 94304-1338 • PO Box 10412, Palo Alto, California 94303-0813 • USA 800.313.3774 • 650.855.2121 • askepri@epri.com • www.epri.com 1015693 ... results of the tasks of Phase of the Boiler Materials for Ultrasupercritical Coal Power Plants project Keywords Ultrasupercritical boilers Boiler materials Materials technology Advanced steam... document that should be cited in the literature in the following manner: Boiler Materials for Ultrasupercritical Coal Power Plants EPRI, Palo Alto, CA, USDOE, Washington, D.C., and OCDO, Columbus,... Boiler Materials for Ultrasupercritical Coal Power Plants 1015693 Technical Update, March 2009 Reporting Period Start Date: