New good practices for emission measurements. and relevance of the SRM with respect to these requirements/practices CEM 2014

Transcription

1 New good practices for emission measurements and relevance of the SRM with respect to these requirements/practices CEM 2014 Jean Poulleau Cécile Raventos

2 Evolution of French rules for emission measurements New reference document LAB REF 22 for accreditation (COFRAC) for emission measurements new rule for summing up concentrations when some are < LoQ new requirements to adapt the implementation of SRMs to the plant with low ELV The French regulation is also moving forward to fix new requirements to be in line with this new document. 2

3 1. Rule for summation of concentrations when some are < LoQ Different configurations, but only one rule for : 1. summing up the concentrations of a compound captured on different compartments of the sampling train: Particulates on the filter or in the probe (rinsing solution) Gaseous compound catched in different impingers or bubblers or cartridge, rinsing ) 2. summing up different compounds of congeners (PCDD/PCDF; PCB, PAH) or heavy metals, specific VOCs! Different rules Difficulty to compare results from one emission source to another Sometimes, the rule of summation may be very conservative maximize the national inventory

4 1.Rule for summation of concentrations when some are < LoQ For results < LoQ/ : the compound will be considered as not detected a zero value will be considered for the summation C = 0 For LoQ/ < C < LoQ : the compound will be considered as detected a LoQ/2 value will be considered for the summation C = LoQ/2 4

5 1. Rule for summation of concentrations when some are < LoQ How to deal with values close to the field blank? Field Blank < 10 % ELV Yes Measure Y Field blank? Yes No No Measure overturned Result : < C blank Result : considered as equal to that of the measurement 5

6 Examples of application for a ELV equal to 70 mg/m 0 : 1. Rule for summation of concentrations when some are < LoQ Examples of application for a ELV = 50 mg/m 0 Measure (M), in mg/m 0 Field Blank (C blank ), in mg/m 0 Compartment 1 Compartment 2 Compartment 1 Compartment 2 Conformity C blank Comparaison M / C blank Result < (LoQ) < 1 (LoQ/) < (LoQ) - C < (LoQ) < 1 (LoQ/),5 < 1 (LoQ/) C,2,8 - C,2 < (LoQ),8 - C,2 < 1 (LoQ/),4 - C 1,5+0 = 1,5 M = C blank = 1,5 1,5+0 <,5 M < C blank <,5,2 <,8 <,8 M < C blank,2+1,5 >,8 M > C blank = 4,7,2+0 <,4 M < C blank <,4,2 < (LoQ) 4,1 < (LoQ) 4,1+1,5 > 5 NC The measurement has to be repeated 6

7 2. An implementation of the SRM adapted to the measurement task The French regulation and LAB REF 22 require : An adaption of the sampling volume and/or duration of sampling A selection of the analytical technique to reach a limit of quantification LoQ < 10 % of the ELV 7

8 2. An implementation of the SRM adapted to the measurement task LAB REF 22 specifies the way to calculate the limit of quantification for the automatic and manual methods: in the case of the automatic methods, LoQ is given EN : LoQ = 4 x S r0 for automated methods for «manual methods», an approximate of LoQ is calculated starting from the LoQ of the analytical step divided by the volume of sample gas : LoQ = 10 x Sr 0 + C average,blank for manual methods Then, check if the uncertainty at this LoQ is actually 60%. (LoQ is determined according to & 5.2. of the standard NF T ) If it is not the case, the LoQ has to be raised. U LoQ 60 % for manual method 8

9 . Relevance of SRMs AFNOR has studied the relevance of the current SRMs with respect to the requirements: The expanded uncertainty at the daily ELV must fulfill the requirement of the SRM and when there is none, it should not exceed 50 % of that of the AMS fixed by the IED U SRM < 0.5 U max,ams LoQ < 10 % ELV 9

10 . Relevance of SRMs : U ELV < 0.5 Umax? Parameter ELV U in % Comments Dust 5 mg/m 0 70 Rinsing of the probe is the main source of uncertainty 10 mg/m 0 60 Criterion : U < 0,5 Umax (15%) is not fulfilled SO 2 (sulfur dioxide) 5 mg/m Criterion : U < 0,5 Umax (10%) is not fulfilled NOx (nitrogen oxides) 50 mg/m 0 extension of sampling duration is not realistic change the SRM? 1 We are close to 0,5 Umax (10%) COT (total organic carbon) 10 mg/m 0 CO (carbon monoxide) 50 mg/m 0 HCl (chlorhydric acid) 10 mg/m 0 HF (fluorhydric acid) 1 mg/m 0 40% 17% 80% No data Criterion can be reached for higher ELV Criterion : U < 0,5 Umax (15%) is not fulfilled Criterion : U < 0,5 Umax (5%) is fulfilled for concentrations > 120 mg/m 0 Criterion : U < 0,5 Umax (20%) is not fulfilled Extend duration to 4h00 or change the method? Criterion U < 0,5 Umax (20%) is not fulfilled change the method 10

11 . Relevance of SRMs : LoQ < 10% ELV? Parameter ELV LoQ comments Dust 5 mg/m 0 10 mg/m 0 SO 2 5 mg/m 0 NOx 50 mg/m 0 COT 10 mgc/m 0 CO 50 mg/m 0 HCl 10 mg/m 0 HF 1 mg/m 0 Cd+Tl 0,05 mg/m 0 Hg 0,05 mg/m 0 Sb, As, Pb, Cr, Co, 0,5 mg/m 0 Cu, Mn, Ni, V PCDD/PCDF 0,1 ng/m 0 2- mg/m 0 0,15 mg/m 0 2 mg/m 0 0,15 mgc/m 0 0, - 1, mg/m 0 0, mg/m 0 ion chromato. 0,0 mg/m 0 spectroscopy 0,5 mg/m 0 Close to 2 µg/m 0 for each compound Close to 2 µg/m 0 Close to 2 µg/m 0 for each compound 0, to 10 pgiteq/m ( m sampled) Criterion LoQ < 1/10 ELV is not fulfilled Necessity to sample higher volumes or on longer periods Use instack filtration when it is possible Criterion LoQ < 1/10 ELV fulfilled LoQ of automatic method is generally worse but some certified instruments can fulfill the criterion Criterion LoQ < 1/10 ELV is fulfilled Criterion LoQ < 1/10 ELV is fulfilled Criterion LoQ < 1/10 ELV is fulfilled LoQ of some certified analysers may be worse Criterion LoQ < 1/10 ELV is fulfilled Criterion LoQ < 1/10 ELV is fulfilled for ELV 5 mg/m 0 Criterion LoQ < 1/20 ELV is fulfilled Criterion LoQ < 1/10 ELV is fulfilled Criterion LoQ < 1/90 ELV is fulfilled LoQ 1/100 ELV for each compound (ICP mass) 11

12 . Relevance of SRMs : Conclusion for incineration For automated and manual SRMs (with a sampling duration of 1 h) most of them fulfill the requirement LoQ < 10% ELV (except dust and HF) For CO, NOx, SO 2, TVOC, Dust, HCl, HF, NH U SRM < 0.5 Umax, AMS is not fulfilled at the daily ELV The target is almost reached for NOx. For manual SRMs a better uncertainty could be reached by carrying out longer sampling, but this could be not sufficient and economically demanding For automatic SRMs, the sensitivity to interfering compounds does not allow reaching a sufficiently low level of uncertainty (CO, tvoc) More selective automated techniques and certified instruments should allow to reach more appropriate level of performance for plants with low ELV (e.g. TDLAS and their variants) 12

13 4. General Conclusion The French accreditation body (Cofrac) has recently fixed new measurement practices and new requirements to implement SRMs and to determine measurement results : a sensible rule for summation of concentrations when some of them are below LoQ, the adaptation of the implementation of the SRMs to reach a LoQ adapted to the measurement task. These good practices allow : to standardize the practices for all the fields (water, air) for the choice of LoQ with a maximum level of uncertainty, to be able to compare the results from one lab to another and from one site to another, to get inventories more representative of the actual situation 1

14 4. General Conclusion Uncertainty of SRMs at the level of low ELV (incineration) is often much higher than what is necessary for the control of the conformity of the plant for low ELV or to calibrate AMS according to QAL2. Owing to the developpement of new automated SRMs and the certification according to EN we can expect that new automated will allow to fulfill these new good practice requirements Thank you for your attention! 14