CEMTEK Environmental SA CC

Transcription

1 CEMTEK Environmental SA CC Stratification and Parallel Testing NOx, SO 2, and CO 2 Multi-Point Parallel Performance Study, Stratification Study and AMS/CEM Relative Accuracy Test Audit Report Prepared for: ESKOM South Africa Komati Power Station Unit 2, 3, 4 and 5, East Stack Komati, Mpumalanga Province Report Date: January 10th, 2015 Revision Number:

2 Report Certification Statements The sampling, data reduction and analysis performed for this report was carried out under my direction and supervision, and I hereby certify that the test results are to the best of my knowledge authentic and accurate. Date: January 10th 2015 Signature: CEMTEK Environmental Brandon Smith Branch Office Manager Komati Unit 1 and Unit 2 West Stack Test

3 TABLE OF CONTENTS TABLE OF CONTENTS... EXECUTIVE SUMMARY INTRODUCTION Test Objectives Facility and Test Locations Test Sampling Points Facility Analysers TEST PROCEDURES CEMTEK Environmental Test Equipment Description Instrument Air Clean Up Sample probe conditioning Sample Transport Tubing Sample Analysis Data Acquisition TEST METHODS BS EN 15259: Sampling Traverse for Stationary Sources BS EN 15259: Determination of Volumetric Flow Rate BS EN 14181/EPA Method 3A: Determination of Percent CO 2 and O BS EN 14181/EPA Method 7E: Determination of NO x Emissions BS EN 14181/EPA Method 6C: Determination of SO 2 Emissions EPA Method 4 (Alternate): Determination of Moisture Content BS EN 14181:2004 Stationary Source Emissions: Annual Surveillance Test Extractive-Dilution: Stationary Source Emissions RESULTS Stratification Tests Parallel / Relative Accuracy Testing Velocity and Volume flow CONCLUSIONS RECOMMENDATIONS APPENDICES... 11

4 LIST OF TABLES Table 1.1 General Information... 3 Table 1.2 Facility AMS Analysers... 4 Table 2.1 Reference Method Analysers... 4 Table 3.1 Test Methods... 6 Table 4.1 SO 2 Stratification Test Results... 8 Table 4.2 RATA Run Exclusions... 8 Table 4.3 Results Difference % and Standard Deviation... 9 Table 4.4 Relative Accuracy Results... 9 Table 4.5 Gas Bias Adjustment Factor... 9 Table 4.6 Velocity and Volume Flow Calculations... 9 Table 4.7 Gas Volume flow of NO, SO 2 and CO APPENDICES Appendix A Quality Assurance / Quality Control Appendix B Stratification Test Data and Results Appendix C Parallel Test and Relative Accuracy Results Appendix D Velocity and Volumetric Flow Appendix E Gas Species Volume Flow Appendix F Straight Line Graphs Appendix G Uncertainty Plot for SO 2, NO & CO Appendix H Test of Variability Appendix I Position of Ports Drawing ABBREVIATIONS AMS: Automated Measuring System SRM: Standard Reference Method CEM: Continuous Emissions Monitor RATA: Relative Accuracy Test Audit

5 1 EXECUTIVE SUMMARY STRATIFICATION AND PARALLEL TESTING OF KOMATI POWER STATION UNIT 2, 3, 4 & 5 (East Stack) OVERVIEW Prior to 2004, air quality legislation in South Africa was based on estimations of emissions from scheduled sources as identified in the Air Quality Act. The Minister of Water and Environmental Affairs, however, gave a General Notice in the Government Gazette, 24 July, 2009 in terms of section 57 (1)(a) of the National Environmental Management: Air Quality Act No. 39 of 2004, of the intention to list activities in terms of section 21 of the Act. The proposed list of activities and their associated minimum emission standards are set out in the Schedule of the General Notice. It is expected with these changes that emissions licenses will be issued to listed industries (Eskom being one of these) based on the actual measured emissions. The only continuous emission measurements undertaken routinely at Eskom power stations were particulate emissions. Since 2005, in anticipation of the new Air Quality Act, all of Eskom s coal fired power stations installed Continuous Emissions Monitoring (CEM) systems on at least one of the stack s flues at each power station. The accuracy of data from each of these installations is important for the application of an appropriate emissions license. This report compares the results from the installed CEM with a standard reference method at Komati Power Station. BACKGROUND Cemtek Environmental was contracted by ESKOM to perform a Multi-Point Gas Stratification Study and Parallel Test on the East Stack, Unit 2, 3, 4 and 5. The Units tested are located at Eskom s Komati Power Station, in Komati, Mpumalanga Province. Testing was performed in accordance with test methods BS E.N , :2009, 15259:2007. The set-up and tests were performed from November 13th, 2015 to November 19th, 2015 OBJECTIVES The specific objectives of the test are: 1).To perform a Multi-Point Gas Stratification Test in order to determine the presence of stratification by measuring SO 2. 2).To locate the Best Average Point for the AMS probe placement from data in 1) above. 3). To compare emissions values between the installed AMS and the Best Average point during tests conducted over an extended period, at normal operating conditions whilst conducting a Parallel Performance / RATA study; and to produce a graph with SRM ppm against AMS ppm. 4). Produce formula to correct gas emission data 5). Calculate total emissions at high load. APPROACH Cemtek Environmental utilised a transportable Continuous Emission Monitoring system for all tests. All tests conformed to the applicable methodologies specified in the appendices to 40 CFR 60. The calibration gases utilised for this program are blended and traceable to the reference material developed and maintained by NMISA. Calibration gases are selected in accordance with 40 CFR 60, Appendix A, Method 6C, Sections through An extractive dilution system with a 100:1 dilution ratio was used to obtain flue gas samples of NO X, SO 2 and CO 2. The sample is continuously withdrawn from the stack, and transported to the RM/SRM (Reference Method / Standard Reference Method) analysers through a conditioned Teflon sample line. The RM/SRM consists of five sub systems: (1) Instrument air clean-up; drying, scrubbing and conditioning (2) Sample probe conditioning, (3) Sample transport tubing, (4) Sample analysis, and (5) Data acquisition.

6 2 RESULTS UNIT 2, 3, 4 and 5: (East Stack) Based on analysis of the stratification traverses on Units 2, 3, 4 and 5, along with the balance of the testing that was conducted on site at Komati power station, the best average point would be 2,510m from stack inner wall utilising port 1. Variance from the mean of ppm at high load was % and 0.999% of the mean. Variance from the mean of ppm at mid load was % and 2.266% of the mean. Variance from the mean of ppm at low load was % and 2.507% of the mean. Load Mean Value Variance from mean High 375 MW ppm % and 0.999% Mid MW ppm % and 2.266% Low MW ppm % and 2.507% The load of 375 MW velocity and volume flow was meters per second and Nm 3 per hour respectively. The gas volume flow of NO x, SO 2 and CO 2 were , and Nm 3 per hour respectively. Gas NO x SO CO CONCLUSIONS Volume Flow (Nm 3 per hour) Gas Measured Relative Accuracy NO ppm (Dry) SO 2 ppm (Dry) CO 2 % (Dry) Four test ports at Komati power station were available for testing on East Stack. An average point was found for placement of measuring gases in the stack on East Stack. Based upon the results of the parallel testing performed on East Stack (U2, 3, 4 & 5) at Komati Power Station, Cemtek has concluded that the relative accuracy for NO x, SO 2 and CO 2 of the installed AMS falls within the acceptable limits. Please note that Cemtek does not measure O 2 continuously and only takes spot readings during the Parallel Test. RECOMMENDATIONS Based on analysis of East Stack (Units 2, 3, 4 & 5) stratification traverses conducted at varying loads (high-mid-low), along with the balance of the testing that was conducted on site. The best averaging point is at distance of 2,510 meters from the stack inner wall in port 1 and the adjustment factors derived are to align the AMS/CEMS readings with this reference point The following adjustment should be implemented (Refer to Appendix F): The NO x should be adjusted using the value appearing in Appendix F (y=0.9385x) The SO 2 should be adjusted using the value appearing in Appendix F (y=1.1101x) The CO 2 should be adjusted using the value appearing in Appendix F (y=1.2601x) KEYWORDS Continuous Emission Monitoring, Sulphur Dioxide, Nitrogen Oxide, Carbon Dioxide, Servomex, Extraction Dilution, Flue Gas,

7 3 1. INTRODUCTION Cemtek Environmental was contracted by ESKOM to perform a Multi-Point Gas Stratification Study and Parallel Test on East Stack, Unit 2, 3, 4 and 5. The Automated Measuring System (AMS) is located at Eskom s Komati Power Station, near Ermelo, Mpumalanga Province. Testing was performed in accordance with test methods BS E.N , :2009, 15259:2007. The set-up and tests were performed from November 13th, 2015 to November 19th, 2015 Table 1.1: General Information Source Name/Address ESKOM - Komati Station (Ermelo, Mpumalanga Province) Unit(s) Tested Test Objectives/Methods Unit 2, 3, 4 and 5(Combined East Stack) Test Date(s) 13/11/ /11/2015 Test Performed By Multi-Point Stratification Test and Parallel Test. Test Methods utilised were from BS E.N , :2009,15259:2007 CEMTEK Environmental SA CC 361 Commissioner Str. Boksburg 1459 PO Box 9655, Cinda Park 1463 Test Personnel Brandon Smith - Branch Manager Emmanuel Mathenjwa Stack Technician Jeffrey Strydom Stack Technician 1.1. Test Objectives To ascertain, the best average point on Unit 2, 3, 4 and 5 (East Stack) by conducting a Stratification Test. 1) To perform a Multi-Point Gas Stratification Test to determine the presence of stratification by measuring SO 2. 2) To locate the Best Average Point 3) To compare emissions values between the installed AMS and the Best Average point during tests conducted over an extended period, at normal operating conditions whilst conducting a Parallel Performance / RATA study and, to show a graph with SRM ppm against AMS ppm. 4) Produce a formula to correct gas emission data. 5) Calculate velocity and volume flow Facility and Test Locations Tests were conducted at Komati Power Station located in Komati, Mpumalanga Province, RSA, on Combined East Stack for Unit 2, 3, 4 and 5. The test location and available ports are at the 150m level. (Total height of stack is 250m). The test location was at least 5 stack hydraulic diameters up-stream, and 2 hydraulic diameters down-stream from any obstruction or source of interference (and at least five hydraulic diameters from the top of a stack)

8 Test Sampling Points For the stratification test, a total of twenty (20) Test Samples were utilised. Sample points were determined using EN 15259:2007(E), D Tangential method for circular ducts guidelines. Points used for the Stratification Test were meters, meters, meters, meters and meters, on each traverse of the 7.70 meter inside diameter stack. The tests were carried out during low, medium and high generating loads, utilising the 20 test points in total and using the 4 available ports. For the parallel / Relative Accuracy test the SRM (or RM) probe was located in port 1 at meters Facility Analysers Table 1.2: Facility AMS Analysers (East Stack, Units 2, 3, 4 & 5) Analyser Manufacturer/Model Range(s) Serial Number NO Outlet SERVOMEX ppm SO 2 Outlet SERVOMEX ppm CO 2 Outlet SERVOMEX 0-25% O 2 Outlet SERVOMEX 0-25% TEST PROCEDURES Cemtek Environmental utilised a transportable Continuous Emission Monitoring system for all tests. The table below specifies the Reference method analysers used during this test program. All tests conformed to the applicable methodologies specified in the appendices to 40 CFR 60. Table 2.1. Reference Method Analysers Analyser Manufacturer / Model Range NO x SN: Thermo Scientific Model 42i (Chemiluminescence NO x Analyser) 0-10 ppm SO 2 SN: Thermo Scientific Model 43C (Pulsed Fluorescence SO ppm Analyser) CO 2 SN:N2T,0889T Fuji Electric Milton Roy 0-2,000 ppm O 2 SN: 001-O 2 -ZA CEMTEK FCA Heated Zirconium Oxide (Hot Wet and Dry) O 2 Analyser 0-25% The calibration gases utilised for this program are blended and traceable to the reference material developed and maintained by NMISA. Calibration gases are selected in accordance with 40 CFR 60, Appendix A, Method 6C, Sections through CEMTEK Environmental Test Equipment Description An extractive dilution system with a 100:1 dilution ratio was used to obtain flue gas samples of NO X, SO 2 and CO 2. The sample is continuously withdrawn from the stack, and transported to the RM/SRM (Reference Method / Standard Reference Method) analysers through conditioned Teflon sample line. The RM/SRM consists of five sub systems: (1) Instrument air clean-up; drying, scrubbing and conditioning (2) Sample probe conditioning, (3) Sample transport tubing, (4) Sample analysis, and (5) Data acquisition. The following sections discuss these five sub systems and their components.

9 Instrument Air Clean Up Instrument air supply from the power station is dried using a high capacity gas-compressor driven air drier. The air is then sent to a twin tower regenerative CO 2 scrubber and 2 nd stage drier. The air is dried to a dew point of -40C. Thereafter the dry air is passed through a 2 nd CO 2 scrubber and drier, activated charcoal scrubber, purafil drier, oil and moisture trap and a final fine particulate filter and moisture indicator. The clean dry air is then sent through a precision dilution air pressure regulator to the probe assembly in the stack Sample probe conditioning The customised in stack dilution sample probe, utilised to extract the flue gas, incorporates the ability to maintain constant heat at approx. 10 degrees Celcius above the flue gas temperature and provides for coarse as well as fine particulate removal. A 50ml glass critical sonic orifice maintains a constant dilution ratio of 100:1 independent of changing stack gas conditions (temperature and/or pressure). The 316-L stainless steel housing and sample tubes are accompanied by a 500W band heater sheathed around the orifice housing and inserted into a stainless steel support tube. Internal probe temperature is controlled by an electronic temperature controller with type K thermocouple feedback sensing of the heated chamber. The other end of the probe consists of a sixty micron sintered stainless steel filter, and packed glass wool that provides fine particulate removal. Calibration gases are injected directly into the heated chamber before the critical orifice at 10 degrees Celsius above actual stack temperature and at a higher pressure than the stack to determine system calibration error testing, under actual extraction pressures Sample Transport Tubing Conditioned Teflon sample transport lines are used to convey sample gas from the probe to the sample distribution system. The sample line does not need to be heated to prevent condensation, as the 100:1 dilution ratio provides a relatively dry sample. At dilution ratios less than 100:1, heating the sample line may be necessary to prevent the formation of condensate that could clog the sample line or cause the flue gas sample to react and change composition. All sample lines are either 3/8"(9.53mm) or 1/4"(6.35mm) Teflon or 316-L Stainless Steel tubes. Four tubes are used for transporting the sample. The first tube carries the sample. The second tube is used for response time checks and calibration error checks. The third tube provides dry, contaminant free, instrument quality air to the educator housing at approx to Bar. The fourth tube is used to monitor the vacuum created by the educator which is maintained at a constant ( to millibar) Sample Analysis The sample is then directed under low pressure into a distribution manifold. Excess sample is vented to the atmosphere via a pressure pump that maintains a constant flow of approximately 1 LPM, available to each analyser. The internal analyser pumps draw in only the amount of sample needed and the excess sample vents outside the test trailer. The Thermo Environmental analysers that were used have internal pumps that supply each instrument with constant sample at or very near atmospheric conditions. The Thermo Environmental analysers also internally compensate for pressure and temperature fluctuations that could adversely affect the measurement of the sample gas. The calibration of the analyser system is conducted in two parts: The out of stack calibration to check analyser response/leaks. The in stack system bias check or (dynamic calibration) is done daily throughout the test period. Calibration gases were verified at the National Metrology Institute of South Africa - NMISA. The cylinders are equipped with pressure regulators that supply the calibration gases to the analysers at the same pressure and flow rate as the sample. Each analyser is checked; during the out of stack system calibration. A zero gas (99.99% pure nitrogen or dry contaminant free instrument quality air may be used), upscale or high span calibration gas is introduced to each analyser and its

10 6 response is recorded. The analyser linearity is acceptable if the monitor response is within 2% of the analyser range. The system bias checks are also accomplished with NMISA gases which are used to zero and Upscale span the analysers. The calibration gas is inserted as close as practical to the probe inlet. In this way the calibration gases are exposed to the same elements as the sample and the monitored response is recorded. The analyser s responses for each calibration gas must agree within ±5% of instrument range. Changes/repairs are made to the system to compensate for any differences in the analyser readings. The system bias results are utilised along with the pre-test calibration values. Upon completion of the sample test run, a post-test calibration error test is performed. The results of the post-test calibration and drift error test must be within ±3% or the test run is void; corrective actions are taken and another test run is performed. The results of the pre and post-test dynamic calibration check are used in correcting the final resultant number. This ensures an accurate average reading for each run, independent of changing conditions at the sampling location. See CFR 40 Part 60 Performance Spec B. RM 6C-SO 2 (C-Gas Calculation) Data Acquisition An ESC 8816 multi-channel data logger; interfaced with a Dell D620 Core Duo portable PC, was used for the mobile laboratory CEM s data acquisition system. All CEM analysers are connected directly to the ESC 8816 DAS that Logs Real Time minute data to an internal memory buffer. The data is later extracted for data reduction via custom Post Processing Software. Logger s data is extracted daily. The ESC 8816 Data Logger communicates with the computer to backup recorded test data and calibrations. All data reduction, data viewing, editing, and printing can be performed at any time without hindering the data logger s acquisition capability. Each channel is scanned at 1 Hz; values are averaged into minute readings 3. TEST METHODS The following is a brief summary of the test methodologies utilised during this test program. Complete method descriptions are presented in the appendices to 40 CFR 60 and BS. EN 14181, 15259, : 2009 Table 3.1 Test Methods Emission Unit Emission Species Test Method Unit 2, 3, 4 and 5 (East Stack) NO BS EN 14181/EPA Method 7E CO 2 and O 2 BS EN 14181/EPA Method 3A SO 2 BS EN 14181/EPA Method 6C Volumetric Flow BS EN Moisture Content EPA Method 4 (Alternate) Unit 2, 3, 4 and 5 (East Stack) Stratification test EN BS EN 15259: Sampling Traverse for Stationary Sources Before the test, a site assessment was performed in order to locate sample points for obtaining the best representative measurements of pollution concentrations. BS EN 15259:2007(E) takes into account; duct area, straight run and cyclonic or stratified flow patterns BS EN 15259: Determination of Volumetric Flow Rate This method is a manual procedure. An S-Type pitot tube with a coefficient of 0.84 was attached to a velocity probe that was capable of traversing multiple points on the stack diameter. Measurements of

11 7 differential pressure, static pressure, temperature, and differential O 2 (wet/dry) were taken at each point. Stack gas CO 2 content was measured with the SRM dilution system. Molecular weight and moisture % by volume was then calculated and used in the final flow calculations. An incline monometer was used to measure the differential pressure and static pressure at each point. The pitot tubes were leak checked and zeroed before and after each test. Sampling points were determined in accordance to BS EN BS EN 14181/EPA Method 3A: Determination of Percent CO 2 and O 2 This method is an instrumental procedure. A sample was continuously extracted from the effluent stream; a portion of the sample stream was then conveyed to an instrumental analyser for the determination of CO 2 concentration. Differential (Wet/Dry) Oxygen levels were measured, where required, in accordance with the Alternative EPA Test Method 4. During each CO 2 sampling run, the moisture percentage (% vol.) was calculated, to correct the wet RM/SRM data to dry to calculate the mg/nm 3 10%O 2 The differences between the AMS monitored readings and the reference method readings were evaluated using all 15 sets of test data. From these differences, the 95% confidence coefficient was calculated and the relative accuracy determined. The relative accuracy results were calculated on a percent basis BS EN 14181/EPA Method 7E: Determination of NO x Emissions This method is an instrumental procedure. Samples by this procedure were taken at the same time using the same traverse points as for the CO 2 determination. The same procedure was used as in section BS EN 14181/EPA Method 6C: Determination of SO 2 Emissions This method is an instrumental procedure. Samples by this procedure were taken at the same time using the same traverse points as used for the NOx and CO 2 determination. The same procedure was used as in section 3.3 and EPA Method 4 (Alternate): Determination of Moisture Content This method is an instrumental procedure using identical type O 2 Sensors. The sample is extracted at each point and is fed directly to a hot/wet O 2 cell for direct measurement. The sample is then immediately dried via a condenser coil and moisture knockout system. The now dry sample is passed through an identical O 2 sensor and the difference in the measurements is recorded. Both O 2 analysers were calibrated immediately prior to the test run. C-Gas Calculation (correction to the monitored data resulting from analyser calibration errors) is performed to ensure that calibration error is not a factor in the total error BS EN 14181:2004 Stationary Source Emissions: Annual Surveillance Test Each sample run, for the relative accuracy / parallel test was at least 30 minutes in duration. A total of 15 sample runs, over 3 days, at varying load conditions. Relative accuracy results are related to the AMS measurement method (i.e. Wet or Dry) Extractive-Dilution: Stationary Source Emissions An extractive dilution system with a 100:1 dilution ratio was used to obtain flue gas samples of NO X, SO 2 and CO 2. The sample is continuously withdrawn from the stack, and transported to the RM/SRM (Reference Method / Standard Reference Method) analysers through conditioned Teflon sample line. The RM/SRM consists of five sub systems: (1) Instrument air clean-up; drying, scrubbing and conditioning (2) Sample probe conditioning, (3) Sample transport tubing, (4) Sample analysis, and (5) Data acquisition. Please refer to Section 2.1 for more information on each sub system.

12 8 4. RESULTS The test results are reported in the following order; Stratification test, Parallel / Relative Accuracy test including tables for: Relative Difference %, Standard Deviation, Relative Accuracy results and Bias Adjustment Factor. Additional results are given on velocity & flue gas volume flow and gas species volume flow Stratification Tests UNIT 2, 3, 4 and 5 (East Stack) Based on analysis of the stratification traverses on Unit 2, 3, 4 and 5, along with the balance of the testing that was conducted on site at Komati power station, the best average point would be 2,510m from the stack inner wall utilising port 1. Variance from the mean of ppm at high load was % and 0.999% of the mean. Variance from the mean of ppm at mid load was % and 2.266% of the mean. Variance from the mean of ppm at low load was % and 2.507% of the mean. All the values fall within the EPA tolerance of 10% for marginally stratified gas. Amended stratification test method was taken from BS EN15259:2007 Stratification tests are conducted with SO 2 because it is the heaviest molecule and is least likely to disperse evenly in the stack. Table 4.1 SO 2 Stratification Test Results East Stack Unit 2, 3, 4 and 5 Load Mean Value Variance from mean High 375 MW ppm % and 0.999% Mid 320MW ppm % and 2.266% Low 257 MW ppm % and 2.507% 4.2. Parallel / Relative Accuracy Testing A total of 15 reference method test runs were conducted during the test program. EN14181 specifies: For each calibration a minimum of 15 valid parallel measurements shall be made with the plant operating normally. These measurements shall be uniformly spread over at least 3 days and over a normal measurement day of 8 hours to 10 hours (e.g. not 5 measurements in the morning and none in the afternoon) and be performed within a period of four weeks. In addition a maximum of three test runs may be excluded from the analysis. The table below presents the test runs that were excluded for each emissions component and the reason for the exclusion. AMS valid calibration range for SO 2 is 0.0mgm mgm 3 AMS valid calibration range for NO is 0.0mgm mgm 3 AMS valid calibration range for CO 2 is 0.0mgm mgm 3 AMS valid calibration range for O 2 is 0% 10.24% Table 4.2 RATA Run Exclusions Emission Run Number Reason for Exclusion Parameter NO ppm Dry Basis NA No Exclusions (all15 runs were used in the final calculations) SO 2 ppm Dry Basis NA No Exclusions (all15 runs were used in the final calculations) CO 2 % Dry Basis NA No Exclusions (all15 runs were used in the final calculations)

13 9 The comparison was conducted at the best average point (2.510 meters) in Port 1. Table 4.3 Results Difference % and Standard Deviation. (See appendix H for Variability) Gas Measured Rel Diff Comment % NO ppm (Dry) 8.34% AMS is higher than the SRM by an average of 8.34% ppm Ave. Absolute Diff. SO 2 ppm (Dry) 10.51% AMS is lower than the SRM by an average of 10.51% ppm Ave. Absolute. Diff. CO 2 % (Dry) 20.77% AMS is lower than the SRM by average 20.77%. 2.42% Average Absolute Diff. Standard Deviation of the mean concentration of the mean concentration of the mean concentration. Based upon the results of the parallel testing performed at Komati Power Station, Cemtek has concluded that the relative accuracy for NO x, SO 2 and CO 2 of the installed AMS does fall within the acceptable limits. Table 4.4 Relative Accuracy Results Gas Measured Relative Accuracy NO ppm (Dry) SO 2 ppm (Dry) CO 2 % (Dry) The calibration function for the AMS is valid: See Appendix G Table 4.5 Gas Bias Adjustment Factor Gas Measured NO ppm (Dry) SO 2 ppm (Dry) CO 2 % (Dry) Bias Adjustment Factor Adjust. The AMS falls within the European requirement Adjust. The AMS falls within the European requirement Adjust. The AMS falls within the European requirement. Please see Appendix F for correction factor 4.3. Velocity and Volume flow Table 4.6 Velocity and Volume flow Calculations Vel trav.@ combined load of 375MW 13/11/2015 AV. Velocity mps. Flow Nm3/Hr(Wet) Table 4.7 Gas Volume flow of NO, SO 2 and CO 2 Gas measured Gas Value Total Wet Gas Gas flow per species Flow Nm 3 /hour Nm 3 /hour NO ppm (Wet) ppm SO 2 ppm (Wet) ppm

14 10 CO 2 % (Wet) 11.64% The load of 375 MW velocity and volume flow was meters per second and Nm 3 per hour respectively. The gas volume flow of NO x, SO 2 and CO 2 were , and Nm 3 per hour respectively. 5. CONCLUSIONS Four test ports at Komati power station were available for testing. An average point was found for placement of measuring gases in the East Stack. Based upon the results of the parallel testing performed on East Stack (U2, 3, 4 & 5) at Komati Power Station, Cemtek has concluded that the relative accuracy for NO x, SO 2 and CO 2 of the installed AMS does fall within the acceptable limits. Please note that Cemtek does not measure O 2 continuously and only takes spot readings during the Parallel Test. 6. RECOMMENDATIONS Based on analysis of East Stack (Units 2, 3, 4 & 5) stratification traverses conducted at varying loads (high-mid-low), along with the balance of the testing that was conducted on site. The best averaging point is at distance of 2,510 meters from the stack inner wall in port 1 and the adjustment factors derived are to align the AMS/CEMS readings with this reference point The following adjustment should be implemented (Refer to Appendix F): The NO x should be adjusted using the highlighted value appearing in Appendix F (y=0.9385x) The SO 2 should be adjusted using the highlighted value appearing in Appendix F (y=1.1101x) The CO 2 should be adjusted using the highlighted value appearing in Appendix F (y=1.2601x)

15 11 7. APPENDICES Appendix A: Quality Assurance / Quality Control Cemtek Environmental applies stringent quality control and quality assurance procedures to ensure the validity of measurements for all source testing. Before testing begins, test protocols are prepared and reviewed. Test protocol review includes selection of appropriate test procedures, evaluation of any interference or other restrictions that might preclude use of standard test procedures, and evaluation and/or development of alternate procedures. Test protocols are further reviewed on site and adapted as needed to ensure the highest level of quality results. The equipment used to conduct emissions measurements is maintained according to the manufacturer's instructions to ensure proper operation. In addition to the maintenance program, calibrations are carried out on each measurement device according to the schedule outlined by the EPA. Quality control checks are also conducted in the field for each test program. The following is a partial list of checks made as part of each AMS parallel test series. Sample acquisition and conditioning system leak checks 2-point analyser calibrations (all analysers) Interference Response Tests (CO 2 NDIR analyser) NO X Converter Efficiency Tests (All Chemiluminescence analysers) Complete system calibration check ("dynamic calibration" through entire sample system) Routine analyser calibration checks are conducted at the start and end of each test period. Any changes between pre and post-test readings are recorded and any inherent biases due to calibration error are factored out according to RM-6C of the CFR 40 Part 60 All calibrations were conducted using gases certified by the manufacturer; which are within ±2% of label value (NIST traceable or equivalent) Gases were additionally measured and certified by NMISA. The NMISA certified gas concentration values were used as the certified concentrations. These values were used when calibrating the gas analysers. Cemtek Environmental maintains full chain of custody documentation on all samples and data sheets. Data sheets are copied and/ or digitised immediately upon return from the field. This first generation copy is placed in secured storage. Any notes on original sheets are initialled and date coded.

16 12 Table Appendix A.1 Sampling Instruments and Equipment Calibration Schedule Instrument Type Frequency of Standard of Acceptance Limits Calibration Comparison or Method of Calibration Orifice Meter (large) 6 months Calibrated dry test ±2% of volume meter. measured Dry Gas Meter 6 months or when Calibrated dry test ±2% of volume repaired. meter. measured S-Type Pitot (for use 12 months EPA Method 2 Cp constant (+5%) over with EPA-type sampling working range; train) difference between average Cp for each leg must be less than 2% Vacuum Gauges 6 months Manometer ±3% Pressure Gauges Field Barometer 6 months Mercury barometer ±0.2" Hg Temperature 6 months NBS mercury ±2 C for < 205 C Measurement thermometer or NBS ±1.5% for >205 C calibrated platinum RTD. Temperature Readout 6 months Precision potentiometer ±2% full scale reading Devices Analytical Balance 12 months (check prior Should be performed by ±0.3mg of stated weight to each use) manufacturer or qualified laboratory. Probe Nozzles 6 months Nozzle diameter check micrometer. Range <±0.10mm for three measurements Continuous Analysers Depends upon use, As specified by Satisfy all limits frequency and manufacturers specified in operating performance. operating manuals. specifications EPA NBS gases and/or reference methods.

17 13 Table Appendix A.2 Equipment Maintenance Schedule Based on Manufacturer s Specifications and CEMTEK Environmental experience Equipment Performance Required Maintenance Interval Corrective Action Pumps Flow Measuring Device Sampling Instruments Integrated Sampling Tanks Mobile Van Sampling Systems Sampling Lines 1. Absence of leaks 2. Ability to draw manufacturer required vacuum and flow 1. Free mechanical movement 2. Absence of malfunction 1. Absence of malfunction 2. Proper response to zero, span gas 3. Interference Response Test Absence of leaks Absence of leaks Sample degradation less than 2%. Every 500 hours of operation or 6 months, whichever is less. Every 500 hours of operation or 6 months, whichever is less. After each test, if used in H2S sampling or other corrosive atmospheres. As required by the manufacturer. Prior to Mobilization Depends on nature of use. Depends on nature of use. After each test or test series. 1. Visual inspection 2. Clean 3. Replace worn parts 4. Leak check 1. Visual inspection 2. Clean 3. Calibrate As recommended by manufacturer 1. Steam clean 2. Leak check 1. Change filters 2. Change gas dryer 3. Leak check 4. Check for system contamination Blow filtered air through line until dry

18 14 Appendix B Stratification Test Data and Results: East Stack High load 375MW

19 15 Data taken from: 13/11/2015 Port 1 Point 5 12h33 Input Values C = Average Measured concentration ppm ( Wet or Actual Basis ) CO = 0.42 Average Zero Response ppm ( Pre and Post Test ) CM = Average Upscale Response ppm ( Pre and Post Test ) CMA = 880 Actual Calibration Gas value ppm O2m Wet = 6.78 % O2m Dry = 7.15 % Ambient O2 = % Mol Wt of SO2 = 64 - Gas N cond deg.c & 1 bar 1. SO2CW ( SO2 - Wet basis - with calibration bias correction ) in ppm SO2CW = ( C - CO ) * CMA / ( CM - CO ) SO2CW = ppm 2. H2O FG ( Moisture Calculation - Based on differential O2 analysis - Wet / Dry ) H2O FG = ( 1 -(( O2mWet / 100 )/( O2mDry / 100 )))* 100 H2O FG = % 3. SO2CD ( Dry Basis - with calibration bias correction ) in ppm SO2CD = SO2CW /( 1 -( H2O FG /100)) SO2CD = ppm 4. SO2CD10%O2 (Dry Basis - with calibration bias correction - corrected to 10% O2 ) in ppm SO2CD10%O2 = SO2CD * ( ( Ambient O2-10 ) / ( Ambient O2 - O2m Dry ) ) SO2CD10%O2 = ppm 5. SO2CD10%O2 convert to mg per Nm3 NO CgasD Cd10%O ppm Mol Wt of NO = 64 - Gas N cond deg.c & 1 bar SO2CD10%O2mg/Nm3 = SO2CD10%O2 * Mol Wt of SO2 / Gas N cond = mg/nm3

20 16 Appendix B Stratification Test Data and Results: East Stack Mid load 320MW

21 17 Appendix B Stratification Test Data and Results: East Stack Low load 257MW

22 18 Appendix B Stratification Test Data and Results: East Stack Average of 3 loads

23 19 Appendix C Parallel Test and Relative Accuracy Results- NOx

24 20 Appendix C: Example Calculations from Spreadsheet measurement dates: Gas concentration measured: Komati East 15,16,18 &19/12/2015 Nitric Oxide 1. Input data Avg SRM(or RM) Data = ppm Avg AMS(or CEM) Data = ppm Difference Avg = ppm N = 15 Number of Data Sets 2. Standard Deviation (SDev) of the differences between Station AMS ( or CEM ) and test SRM ( or RM ) Definition of standard Deviation: Positive square root of: the mean squared deviation from the arit 3. Confidence Coefficient CC Summed Differences = Summed Diffs Squared Di2 = Algebraic Sum of the individual differences (di2) squared Summed Diffs Sq /# meas. = Sum of (Diff* Diff ) Di = Algebraic Sum of the squared individual differences (di) Standard Deviation = SQRT * ( ( Di - ( Di2 / N ) ) / ( N -1 ) ) Standard Deviation = Definition of Confidence Coefficient or confidence interval:

25 21 Table Reference: MID Version 2.3 June 2010 Appendix 3 kv values and t-factors, Table A4.1 Number of parallel measuremkv(n) t0.95(n-1) For Confidence Coefficient of N number of points is used from the above table Confidence Coefficient = t *( Sdev / sqrt (N)) CC = Relative Accuracy RA Definition of Relative Accuracy or Calibration Function : linear relationship between the values of the SRM and the AMS with the assumption of a constant residual standard CC = Confidence Coefficient Diffavg = Mean of Differences ppm SRM(or RM)avg = SRM Average Value ppm 100 = 100 Value converted to percentage RA = 100 * ( ( Diffavg + CC ) / SRM (or RM)avg ) = %

26 22

27 23 Appendix C Parallel Test and Relative Accuracy Results SO 2

28 24

29 25 Appendix C Parallel Test and Relative Accuracy Results CO 2

30 26

31 27 Appendix D Velocity and Volumetric Flow CEMTEK Environmental Customer Eskom Komati Power Station Unit ID Unit 2,3,4 & MW = 375 Location East Stack Load = High Pitot # S.A.-001-A - Date 13/11/2015 Pitot Coeff Technicians B. Smith Probe # S.A Pitot Pre Lkg Che 3.8 In Analysis CO2 Wet O2 Dry O2 Wet Pitot Post Lkg Ch 4.2 In Number % % % Mol Wt Flue gas kg/kg mole 1 Atmos. Press kpa 2 Abs. Press kpa 3 Area of Flue m2 Average % Moisture % Vol. Time per point Run # 3 Start: 12h33 Stop: 19h47 Stack Int Dia m 7.7 Traverse Delta P Delta P Temp Press. Static Velocity Flow Vol Point In / H20 SQRT Stack oc In / H2O m / s Nm3/m(wet) Port 1 Pos Port 1 Pos Port 1 Pos Port 1 Pos Port 1 Pos Port 2 Pos Port 2 Pos Port 2 Pos Port 2 Pos Port 2 Pos Port 3 Pos Port 3 Pos Port 3 Pos Port 3 Pos Port 3 Pos Port 4 Pos Port 4 Pos Port 4 Pos Port 4 Pos Port 4 Pos Averages Min Max Std Dev Con.to kpa Con.to kpa oc Con.to kpa m / s Nm3/m(wet) Averages

32 28 Input Data Barometric Press = kpa Static Press = -0.5 inches of H2O Ave CO2 % Wet = % Average FG temp = 140 Deg.C Cal. of pitot tube = Delta P = inches of H2O Stack Int Area = m2 O2m Wet = 6.78 % O2m Dry = 7.15 % Gas N cond = deg.c & 1 bar Mol Wt of CO2 = 44 - Mol Wt of H2O = 18 - Mol Wt of O2 = 32 - Mol Wt of N2 = Sample Absolute Pressure Barometric Press = kpa 1mmH20 = kpa Static = kpa 1 inchh2o = kpa Absolute Press = kpa Static = -0.5 inches of H2O "H2O to kpa = kpa 2. H2O FG ( Moisture Calculation - Based on differential O2 analysis - Wet / Dry ) H2O FG = ( 1 - ( ( O2mWet / 100 ) / ( O2mDry / 100 ) ) ) * 100 H2O FG = % 3. Molecular Weight of Wet Flue Gas Stream Mol Wt of Wet FG = (CO2%W*44+H2O%*18+O2%W*32+N2%W*28)/100 Mol Wt of Wet FG = kg per kg Mol 4. Density of Wet Flue gas at Normal conditions ( 0 Deg.C and kpa ) Density of flue gas = Mol Wt of wet FG / Gas N cond Density of flue gas = kg / Nm3 5. Density of Wet Flue gas at actual conditions Dens.of W FG Act = Density of FG at N cond * ( / ( Average FG temp)) * (Abs P / ) Dens.of W FG act = kg / Am3 6. Average velocity of Wet Flue gas metres per second Ave Vel of Wet FG = Cal of Probe * SQRT (2000) * SQRT (Delta P ) / SQRT ( Act Density ) Ave Vel of Wet FG = m / s 7. Total Wet Gas Flow ( Am3/min ) at act cond ( 140 Degree C & kpa ) Total Wet Gas Flow ( Am3/min Komati ) Unit = 2, 3, 4 Af and * Vs 5 * East 60 Stack Test Total Wet Gas Flow ( Am3/min ) QmAw = Am3/min

33 29 8. Total Wet Gas Flow ( Nm3/min ) at N. cond ( 0 Deg.C and kpa ) Total Wet Gas Flow ( Nm3/min ) QmNw = Total Wet Gas Flow ( Nm3/min ) QmNw = Total Wet Gas Flow ( Nm3/hour ) QhNw = QmAw * Da / Dn Nm3/ min Nm3/ hour 9. Total Dry Gas Flow ( Am3/min ) at act cond ( 140 Degree C & kpa ) Total Dry Gas Flow ( Am3/min ) = QmAw * ( 1 - ( H2O FG / 100 ) ) Total Dry Gas Flow ( Am3/min ) QmAd = Am3/min 10. Total Dry Gas Flow ( Nm3/min ) at N. cond ( 0 Deg.C and kpa ) Total Dry Gas Flow ( Nm3/min ) = QmNw * ( 1 - ( H2O FG / 100 ) ) Total Dry Gas Flow ( Nm3/min ) QmNd = Nm3/min

34 30 Appendix E Gas Species Volume Flow

35 31

36 32

37 33 1. Inputs NO CgasW = ppm SO2 CgasW = ppm CO2 CgasW = % Total Wet Gas Flow ( Nm3/ min ) Nm3/min 2.1. Volumetric flow of NO2 (Nm3/min& Nm3/ Hour) Total Wet Gas Flow ( Nm3/ min ) Nm3/min NO CgasW = ppm Note: NO ppms are equal to NO2 ppm Volumetric flow of NO2 Volumetric flow of NO2 = Nm3/ min = Nm3/ Hour 2.2. Mass flow of NO2 (kg/min & kg/ Hour) Mol Wt of NO2 = 46 - Gas N cond = deg.c & 1 bar Density 0 Deg.C & k kg / Nm3 Mass flow of NO2 Mass flow of NO2 Mass flow of NO2 Density of NO2 * Volumetric flow of NO kg/min kg/hour 3.1. Volumetric flow of SO2 (Nm3/min & Nm3 / Hour) Total Wet Gas Flow ( Nm3/ min ) Nm3/min SO2 CgasW = ppm Volumetric flow of SO2 (Nm3/mi Nm3/ min Volumetric flow of SO2 (Nm3/Ho Nm3/ Hour 3.2. Mass flow of SO2 (kg/min & kg/hour) Density 0 Deg.C & k 2.86 kg / Nm3 Reference: Measured density of 0 Deg.C & kpa is taken from GIECK Technical Formulae Table: Z6 Properties of Gases if 2.92 kg/nm3 is used Mass flow of SO2 Mass flow of SO2 Mass flow of SO2 =Density of SO2 * Volumetric flow of SO2 = kg/min = kg/hour 4.1. Volumetric flow of CO2 (Nm3/min & Nm3/Hour) Total Wet Gas Flow ( Nm3/ min ) Nm3/min CO2 CgasW = % Volumetric flow of CO2 (Nm3/mi Nm3/ min Volumetric flow of CO2 (Nm3/Ho Nm3/ Hour 4.2. Mass flow of CO2 (kg/min & kg/hour) Mol Wt of CO2 = 44 - Gas N cond = deg.c & 1 bar Density 0 Deg.C & k kg / Nm3 Mass flow of CO2 Mass flow of CO2 Mass flow of CO2 Density of CO2 * Volumetric flow of CO kg/min kg/hour

38 34 Appendix F Straight Line Graphs

39 35

40 36 Appendix G Uncertainty Plot for SO 2, NO, CO 2

41 37

42 38 Appendix H. Test of Variability for NO, CO 2 and SO 2 respectively Test of Variability The variability is accepted if: s D σ k O v where s D is the standard deviation of the differences D i σ k v O is the uncertainty laid down by the authorities is the test parameter The standard deviation sd is given by s D = 1 N 1 N i = 1 ( D D ) 2 = mg m -3 The uncertainty laid down by the authorities is 20% of the ELV as a 95% confidence interval. So the formula is: s D σ k 96 O v is calculate as: σ O = %E /1. = 0.2 * 1100 / 1.96 = mg m -3 For 15 measurments the kv value is The test for variability then results in: mg m mg m -3 x mg m mg m -3 which is fulfilled. The AMS passes the test. Test of Variability The variability is accepted if: s D σ k O v where sd is the standard deviation of the differences Di σ kv O is the uncertainty laid down by the authorities is the test parameter The standard deviation sd is given by s D = 1 N 1 N i = 1 ( D D ) 2 = mg m -3 The uncertainty laid down by the authorities is 20% of the ELV as a 95% confidence interval. So the formula is: s D σ k 96 O v is calculate as: σ O = %E /1. = 0.2 * 3500 / 1.96 = mg m -3 For 15 measurments the kv value is The test for variability then results in: mg m mg m -3 x mg m mg m -3 which is fulfilled. The AMS passes the test.

43 39 Test of Variability The variability is accepted if: s D σ k O v where sd is the standard deviation of the differences Di σ kv O is the uncertainty laid down by the authorities is the test parameter The standard deviation sd is given by s D = 1 N 1 N i= 1 ( D D) 2 = mg m -3 The uncertainty laid down by the authorities is % of the ELV as a 95% confidence interval. So the formula is: s D σ k σ O = %E /1. 96 O v is calculate as: = = 0.2 * / mg m -3 For 15 measurments the kv value is The test for variability then results in: 13, mg m -3 32, mg m -3 x , mg m -3 31, mg m -3 which is fulfilled. The AMS passes the test.

44 40 Appendix I Position of Ports Drawing