SUMMARY - NLA

SUMMARY Why PresentIntroductionGeneral ExperienceWhat is FTIRGases Measured with FTIRFTIR vs SRMAdvantages of FTIRDisadvantages FTIRBasic OperationQuality Assurance and Quality ControlTake Home Points

WHY PRESENT Passionate about air quality Improve air quality measurement in South Africa Awareness of improved measurement techniques

INTRODUCTION Industrial installations have requirement to quantity emissions to atmosphere Accurate and reliable measurements Legal compliance Engineering studies Impact assessments Instrumental techniques are preferred Continuous emission monitors require correlation Portable multigas FTIR analysers are ideal for periodic and semi-continuous monitoring

GENERAL EXPERIENCE Stack testing for 23 years Projects covering most pollutants listed in Section 21 Regulations Instrumental Manual South Africa and Africa Real-time measurements hold value

WHAT IS FTIR Fourier-Transform Infra-Red spectroscopy (FTIR)Full-spectrum analytical technique that allows all IR absorbing species to be detected and measuredIt is complex technology?Commercial products available on the market utilizes specialized softwareFTIR analysis can measure and detect nearly all gases, exceptions are; Homonuclear diatomic gases – O2, N2, H2, Cl2 Inert gases – He, Ar, etc. Some gases have weak absorbance, e.g. H2S

GASES MEASURED WITH FTIR CO, NO, NO2, SO2, HCl, HF, NH3, CO2, H2O, O2Natural gas/syngasSiloxanesVolatile organic compounds and total volatile organic compoundsGreen house gases, SF6, N2O, etc.Many more

FTIR vs SRMSRM MethodFTIREPA Method 3 – O2, CO2YesEPA Method 4 – H2OYesEPA Method 6 – SO2YesEPA Method 7E – NO, NO2, NOxYesEPA Method 8 – SO2, SO3YesEPA Method 10 – COYesEPA Method 11 – H2S ( 50 ppmYesEPA Method 16 – TRSYes, including mercaptans and other reduced sulphursEPA Method 18 – VOC’sYesEPA Method 26 – HCl, HFYesEPA CTM 027 – NH3Yes

ADVANTAGES OF FTIR One analyserHot/wet analyses – no need for sample conditioning, no sample lossSingle gas mix as check gas; fast pre and post-test checkingMeasurement ranges are not limitedSampling spectra can be interrogated post-test – unknown gasSoftware reports a “residual”Real-time measurementsNo samples to recover, store and costly analysisEasy comparison vs CEMS during EN14181 campaigns

DISADVANTAGES OF FTIR One analyser Expensive Trained skilled personnel

BASIC OPERATION OF FTIR Power on, connect to laptop and open softwareAllow 60 to 120 minutes warm upProbe heated to 180oCHeated sample line at 180oCZero gas cell purge, generate zero backgroundZero check down sampling line, perform LOD checksCheck gas (single gas mixture CO, NO, SO2 and C3H8) Not a traditional span, intrinsic validation of the analysers’ functionalityIf sampling for HCl, HF or NH3 perform a reactive gas checkInsert probe into stack and collect dataOnce per 24 hours perform zero and check gas drift checksOn completion, perform zero, check gas and reactive gas check

QA/QC Zero gas – Collect at least 10 spectra and at least 3x T90Check gas concentration not more than 3x ELVCheck gas passed over entire sample train, most reactive target gas should be includedCheck gas at least 3x T90Very reactive gas tests performed (HF, HCl and NH3)Gas(ranked from most to least reactive)HF2HClNH3SO2NO2CO2N2ONOCO

QA/QC Check gas is not a conventional span but a validation of the functionality of the FTIR FTIR instrument is able to produce spectra of sufficient accuracy, in terms of both absorbance peak heightand width and that this is achievable at (or near) the wavenumber region that is used by the chosenanalytical model Example: CO analytical band 2000-2200 (central band 2100 /- 25%). It can be seen for this analytical band,CO or NO could be used as check gas.

QA/QC Table below shows common analysis bands and examples of suitable check gases.Example AnalysisBands ComponentAnalysisband fromAnalysisband e check YesCO2 Band 122912376233417502917YesYes-YesYesCO Band 121332201216716252709YesYes-Yes-N2O Band 11294131013029761627YesYesYesYesYesN2O Band 221512223218716402734YesYesYesYesYesN2O Band 325272634258119353226YesYesYesYesYesNO Band 118511864185813932322YesYesYesYesYesNO Band 218741913189314202367YesYesYesYesYesNO Band 328073159298322373729YesYesYesYesYesNO2 Band 115481677161312102016-YesYes--SO2 Band 112951415135510161694--Yes--NH3 Band 18999699347011168Yes--YesYesNH3 Band 228113161298622393732Yes--YesYesHCl Band 128713161301622623770---YesYesHF Band 128113161298622393732---YesYesHF Band 240574333419531465244Yes--YesYes

TAKE HOME POINTS Real time measurements using a portable multi-gas analyserImmediate indication of compliance for HCl, HF, NH3 and other compounds of interestEffective decision making and prompt actionProcess optimisationNot only about the minimum emission requirements

THANK YOU Thank you

EPA Method 7E –NO, NO 2, NOx Yes EPA Method 8 –SO 2, SO 3 Yes EPA Method 10 –CO Yes EPA Method 11 –H 2 S ( 50 ppm Yes EPA Method 16 –TRS Yes, including mercaptans and other reduced sulphurs EPA Method 18 –VOC’s Yes EPA Method 26 –HCl, HF Yes EPA CTM 027 –NH 3 Yes. ADVANTAGES OF FTIR