Return to DOE Report Table of Contents

Return to Advanced Second Generation Ceramic Candler Filters Table of Contents

Advanced Second Generation Ceramic Candle Filters,
Topical Report - January 31, 2002

M. A. Alvin

Siemens Westinghouse Power Corporation

In this pdf format, this document has 74 pages and is 2.83MB.

Table of Contents

ABSTRACT
1 INTRODUCTION 1
2 ADVANCED SECOND GENERATION POROUS CERAMIC CANDLE FILTERS 5
 

2.1

 Thermal/Chemical Stability 10
  2.1.1 3M CVI-SiC Composite Filter Matrix 11
2.1.2 DuPont PRD-66 Filament Wound Filter Matrix 14
2.1.3 DuPont SiC-SiC Composite Filter Matrix 15
2.1.4 IF&P FibrosicTM Filter Matrix 17

2.2

 Mechanical Properties of the As-Manufactured Second Generation Filter Elements 18
3 ASSESSMENT OF PROTOTYPE ADVANCED SECOND GENERATION CANDLE FILTER HIGH TEMPERATURE PERFORMANCE 22
 

3.1

 Bench-Scale Testing 22
 

3.1.1

 Microstructural Characterization of the DuPont SiC-SiC Candle Filter Matrix 25

3.2

 Demonstration Plant Testing 26
 

3.2.1

 Siemens Westinghouse Advanced particulate Filtration System 27

3.2.2

 Coupon Testing 29
3.2.3 3M CVI-SiC Composite Filter Testing 32
3.2.4 DuPont PRD-66 Filament Wound Filter Testing 34
3.2.5 Comment 36
4 QUALIFICATION TESTING OF ADVANCED SECOND GENERATION CANDLE FILTERS 37
 

4.1

 Material and Component Modifications 37

4.2

 Bench-Scale Testing 38
  4.2.1 Filter Element Down-Selection 44
4.2.2 Recommendations for Foster Wheeler PCFBC Testing 49

4.3

Foster Wheeler PCFBC Testing

 50
5 PROGRAM SUMMARY 59
6 CONCLUSIONS 64
7 ACKNOWLEDGEMENTS 65
8 REFERENCES 66
         
TABLES
Table 2.1 - Diametral Compressive Strength of the 3M CVI-SiC Composite Mini-Candle Reinforced Flange 12
Table 2.2 - Strength Characterization of the Steam/Air and Alkali/Steam/Air-Exposed 3M CVI-SiC Composite Candles 13
Table 2.3 - Strength Characterization of the Steam/Air and Alkali/Steam/Air-Exposed DuPont PRD-66 Mini-Candles 15
Table 2.4 - Strength of the Reinforced Flange and End Cap Sections of the DuPont PRD-66 Mini Candles after Flow-Through Testing 15
Table 2.5 - 4-Point Bend, ¼-Point Flexural Strength of the Steam/Air and Alkali/Steam/Air-Exposed DuPont SiC-SiC Filter Matrix 17
Table 2.6 - Load and Ultimate Strength of the As-Manufactured Second Generation Candle Filters 20
Table 2.7 - First Generation Monolithic and Advanced Second Generation Candle Filter Material Strength 21
Table 3.1 - Summary of Siemens Westinghouse APF Testing under PFBC Conditions at AEP 28
Table 3.2 - Summary of the C-Ring Compressive Strength and Microstructural Changes Resulting in the Second Generation Filter Materials after Exposure above the Siemens Westinghouse APF Tubesheet at AEP 30
Table 3.3 - Candle Filter Matrix Strength 34
Table 4.1 - Residual Filter Dust Cake Layer after Qualification Testing 40
Table 4.2 - Room Temperature and Process Temperature Strength of the As-Manufactured and Qualification-Tested Porous Ceramic Candle Filters 43
Table 4.3 - Ultimate Load Applied during Strength Characterization of the As-Manufactured and Qualification-Tested Porous Ceramic Candle Filters 45
Table 4.4 - Material Properties of the As-Manufactured and Qualification-Tested Advanced Monolithic and Composite Candle Filters 46
Table 4.5 - Shear Strength fo the As-Manufactured and Qualification-Tested Techniweave Candle Filter Flange and End Cap 48
Table 4.6 - Summary of PCFBC Testing 51
Table 4.7 - Techniweave NextelTM 720 CFCC Candle Filter Material Properties 55
Table 4.8 - X-Ray Diffraction Analysis of the 3M Oxide-Based CFCC Candle Filters 55
Table 4.9 - Layer Adherence Testing of the 3M Oxide-Based CFCC Candle Filters 56
Table 4.10 - 3M Oxide-Based CFCC Candle Filter Material Properties 56
         
FIGURES  
Figure 1.1 - Siemens Westinghouse Advanced Particulate Filtration systems 1
Figure 1.2 - First generation monolithic and advanced second generation candle filters 2
Figure 2.1 - 3M CVI-SiC composite filter matrix 6
Figure 2.2 - DuPont PRD-66 filament wound filter matrix 7
Figure 2.3 - DuPont SiC-SiC CFCC Filter Matrix 8
Figure 2.4 - IF&P FibrosicTM Filter Matrix 9
Figure 2.5 - Bench-scale, high temperature, flow-through test facility 10
Figure 2.6 - 3M CBI-SiC mini-Candles after exposure to high temperature flow-through testing 11
Figure 2.7 - Oxidation of the steam/air and alkali/steam/air-exposed 3M CVI-SiC filter matrix 13
Figure 2.8 - Cracks and spalled areas of the o.d. surface membrane of the 400 hour, 870°C, 20 ppm NaCl/5-7% steam/air-exposed DuPont PRD-66 filter matrix 14
Figure 2.9 - DuPont SiC-SiC composite matrix after 400 hours of exposure at 870°C to the 20 ppm NaCl/5-7% steam/air flow-through test environment 16
Figure 2.10 - Glazed sodium-enriched surface membrane of the DuPont SiC-SiC composite candle filter matrix after 400 hours of exposure to the 870°C, 20 ppm NaCl/5-7% steam/air flow-through test environment 17
Figure 2.11 - IF&P FibrosicTM filter disc after 400 hours of exposure at 870°C to the 5-7% steam/air flow-through test environment 18
Figure 2.12 - Room temperature gas flow resistance of the first generation monolithic and advanced second generation candle filters. 19
Figure 3.1 - Siemens Westinghouse PFBC simulator test facility 22
Figure 3.2 - Ruptured seam of the DuPont SiC-SiC composite candle filter after process transient testing 23
Figure 3.3 - Fractured IF&P FibrosicTM candle filter after exposure to 1645 accelerated pulse cycles in the simulated PFBC operating environment 24
Figure 3.4 - Removal of the interface layer and bonding of the NicalonTM fibers to the silicon carbide structural matrix in the DuPont SiC-SiC filter material after exposure to simulated, accelerated life, PFBC testing 26
Figure 3.5 - Siemens Westinghouse Advanced Particulate Filtration system 27
Figure 3.6 - Crack formations along the silica-enriched CVI-SiC infiltrated layers that surrouned the NextelTM 312 fibers in the triaxial braid of the 3M composite filter matrix after 2815 hours of exposure above the Siemens Westinghouse APF system tubesheet at AEP 30
Figure 3.7 - Crack formations and bonding of the NicalonTM fibers to the oxygen-enriched inner wall of the CVI-SiC encapsulating layers in the DuPont SiC-SiC double-ply felt composite filter matrix after 4094 hours of exposure above the Siemens Westinghouse APF system tubesheet at AEP 31
Figure 3.8 - Removeal of the CVI-SiC coating along the outer confinement layer of the 3M CVI-SiC composite filter element after 387 hours of operation at AEP 32
Figure 3.9 - Morphology of the 3M CVI-SiC composite matrix after 1705 hours of operation in the 732°C PFBC environment 33
Figure 3.10 - Divot formations along the length of the DuPont PRD-66 filter elements after Testing at AEP 35
Figure 3.11 - Delamination within the as-manufactured, filament wound, DuPont PRD-66 filter matrix 36
Figure 4.1 - Filter array used in the Siemens Westinghouse Qualification test program 39
Figure 4.2 - Filter array at the conclusion of Siemens Westinghouse qualification testing 40
Figure 4.3 - Gas flow resistance of the qualification-tested filter elements prior to and after exposure in the Siemens Westinghouse PFBC simulator test facility 41
Figure 4.4 - Variation in the wall thickness and flange contour of the monolithic and advanced filter elements 42
Figure 4.5 - Bulk strength of the as-manufactured and qualification-tested advanced monolithic and composite candle filters 44
Figure 4.6 - Load bearing capabilities of the as-manufactured porous ceramic candle filters 47
Figure 4.7 - Failure of the Scapa CerafilTM filter element during Siemens Westinghouse simulated PFBC qualification testing 47
Figure 4.8 - Shear failure of the Techniweave filter element during Siemens Westinghouse simulated PFBC qualification testing 48
Figure 4.9 - Advanced composite filter element testing at the Foster Wheeler test facility in Karhula, Finland 53
Figure 4.10 - Gas flow resistance of the 3M CVI-SiC candle filters 54
Figure 4.11 - Siemens Westinghouse Advanced Particulate Filtration system at the conclusion of testing at the Foster Wheeler PCFBC test facility in 1997 58