Emissions Cracking the Candle s Code Chemistry meets Cryptography. 2 nd World Candle Congress, Cancún, June 2007 by Dr.

Transcription

1 Emissions Cracking the Candle s Code Chemistry meets Cryptography 2 nd World Candle Congress, Cancún, June 2007 by Dr. Michael Matthäi

2 Overview General introduction Ökometric study Candle s code Conclusion 2

3 Part 1: General Introduction Enigmas are there to be cracked! Code of the Quipu of the Incas Egyptian hieroglyphics 3

4 The Aztec Calendar The Cuetzpalin, lizard of the Aztec calendar, symbolises a good day to work on reputation through action. 4

5 My Personal Involvement with an Enigma for the last 3 Years Pictograms vs. Hieroglyphics 5

6 The Candle & Science Michael Faraday, "There is not a law under which any part of this universe is governed which does not come into play and is touched upon in these phenomena. There is no better, there is no more open door by which you can enter into the study of natural philosophy than by considering the physical phenomena of a candle." 6

7 Why are Candle Emissions being Focused on? The consumer of today has the right to demand high quality products, the use of which do not present a hazard to people or the environment. Global warming has created an increase in ecological awareness for all kinds of emissions. Interest in indoor air quality has increased too Unsubstantiated claims of sooting petroleum-based candles vs. non-sooting vegetable-based ones employed as marketing tools. 7

8 Candle Studies and Reports All kinds of reports concerning candles, their combustion and harmful substances related to them have been gathered and classified: more than 120 items since 1970 Extraction of relevant reports concerning candle emissions during combustion experiments in the lab: 24 international papers since

9 Evaluated Reports ( ) 24 international papers Is there a Rosetta Stone to read the Candle s Code somewhere in them? Egyptian hieroglyphics Rosetta Stone discovered in

10 Part 2: The Ökometric Study IGI Sasol Wax 10

11 Collaborative Study The Illustrious Group of Code Crackers NCA AECM 11

12 Faced with an Enigma It may well be doubted whether human ingenuity can construct an enigma... which human ingenuity may not, by proper application, resolve. Edgar Allan Poe ( ) US short story author, editor, & poet 12

13 Purpose of the Study to Crack the Candle s Code Aim to characterize candle emissions for different materials Evaluate results against exposure limits for emitted chemicals Particular matter, investigation of particle size distribution Investigate correlations between visible and invisible emissions for different candle materials (hourly soot indexes) 13

14 Ökometric Offer Ökometric 14

15 Evaluation the Influence of Raw Materials Paraffin Wax Stearic Acid Fats Beeswax 15

16 Emission Components Burning Volatile organic components (VOC) Alkanes Benzene Aldehydes: - Formaldehyde - Acetaldehyde - Acrolein - Propionaldehyde Semi / low volatile organic components Dioxins/ Furans: - PCDD - PCDF PAH Gases e. g. CO 2 Soot / Particulate matter Amount: - mass - soot index particle size: - fine dust chemical characterisation 16

17 Money Main Limitation of the Investigation A limited number of raw materials were tested and only 2 of them were sooting systems. Additives (e. g. fragrances, dyes ) were not considered. No detailed chemical analysis of soot was undertaken. 36,000 Euro 45,000 US$ 17

18 Emission Concentrations How little is 1 ng? 1 ng = g or 1 ng has the same ratio to 1 g as 2 nickels (0.05 US$) to the weight of the Eiffel Tower 18

19 Comparison of the Raw Materials All the raw materials examined in the Ökometric study: Emit the same group of chemical substances. Have emission quantities of the same order of magnitude. Have a comparable ratio on a very low absolute level. 19

20 2.5 m = 8.2 Scenario for Evaluation 5 m = 16.4 Room volume = 5 m x 4 m x 2.5 m = 50 m³ = 1766 ft³ 4 candles, Ø top = 63 mm height = 90 mm 4 hours burning time no air exchange! 20

21 Limit Values for the Calculation Scenario AGW-values, TRGS 900: Work place limit values MAK-values: Former maximum work place levels TRK, TRGS: Former technical guidance values MIK-values: Maximum immission concentrations WHO-values: WHO air quality guideline for Europe RfC: Inhalation reference concentration STEL: Short-term Exposure Level PEL: Permissible Exposure Level LAI-values: LAI target value for air protection IRK/ALOG: Guidance value EU-values: European target values for ambient air NIK / AgBB values: Lowest concentration of interest, committee for the health oriented evaluation of building products. TRGS 21

22 Results of Evaluation There are no general indoor air quality standards available for all the relevant emitted substances. None of the considered air quality standards were exceeded, or even reached. The sooting candles show increased emission rates in some cases, but are still within the limit values. The emission increase for the sooting candles was not as high as expected. 22

23 23 Particulate Matter Results from SEM

24 Particulate Matter Energy-Dispersive X-ray Analysis (EDXA) the raw material cannot be identified from the diagram 24

25 Particulate Matter Results No significant differences between the individual materials tested SEM shows primary particles (spherical) in accordance with the basic soot formation theory Particles growth through coagulation and agglomeration The experimental conditions have a very strong influence on the size of the agglomerates. The existing method to determine the particle size distribution is not suitable with the experimental set-up used. 25

26 Soot Index vs. Emission There is a correlation between the visible and invisible emissions. No exact formula yet but a marked tendency. 26

27 Our main Objective is the Production of Good Candles All the raw materials examined can be, and are, used to make good candles. 27

28 28 Part 3: The Candle s Code

29 The Candle s Code 24 international papers incl. the Ökometric study Limited comparability, repeatability Different methods Missing information (e. g. fuel flow, material, conditions) Inconsistent evaluations, limits National languages Are uniform methods necessary? 29

30 Testing Matrix Paraffin Wax Fat Stearin Beeswax Others Pure Material X X X X X Blends Colours Fragrances Lacquers Additives 30

31 The Candle s Code The riddle of the candle s code is hidden in hieroglyphics which need to be deciphered. Evaluation of the 24 papers incl. the Ökometric study. Which parameter can be used as our Rosetta Stone? Rosetta Stone 31

32 Candle System 3 1 Cn H2n 2 n O2 n CO2 n 1 H2O m Cn H2n Om n O2 n CO2 n H2O 2 2 Material burning condition Shape Wick 32

33 Example PAH: Distribution of the Results PAH *) not detectable 33

34 Example PAH: Do the Results depend on the Candle s Shape? *) not detectable 34

35 Do the Results depend on the Wick? The wick determines the fuel flow. The fuel flow determines the flame size. The fuel flow determines the carbon concentration in the flame. The fuel flow influences sooting behaviour. 35

36 Example PAH: Do the Results depend on the Sooting Behaviour? *) not detectable 36

37 Fuel Flow What happens if a candle soots? C-concentration in the flame is too high for complete combustion Fragments of the candle material gather in the flame The fragments both: accumulate to greater visible pieces visible soot react uncontrollably to a variety of different substances non visible emissions The system is, then, out of control. Conclusion: The occurrence of soot is also a clear sign for the presence of non visible emissions. 37

38 soot index/h Fuel Flow vs. Emissions 4,5 4 3,5 The wick selection determines the fuel flow. 3 2,5 2 Vcrit1 (Material 1) 1,5 1 0,5 SI > 1/h: sooting candle SI = 1/h: quality candle Vcrit2 (Material 2) fuel flow V [g/h] 38

39 The Candle s Code The fuel flow is our Rosetta Stone. The fuel flow determines the: burning time brightness flame size emissions non sooting / sooting g/hour All future investigations must evaluate the results under consideration of the fuel flow. 39

40 Part 4: Conclusion Thesis: The candle is a system. All materials tested are suitable for making good candles. The key parameter for emissions is the fuel flow. 40

41 Part 4: Conclusion Thesis: The critical fuel flow differentiates between sooting and non sooting candles. Below the critical fuel flow the emissions are far lower than air quality standards limits. Soot measurement is an adequate quick check for candle emissions too. 41

42 Formula for Success Everything High quality should raw be materials made as simple as + Candle possible, know-how but not (e. simpler. g. wick selection) Albert Einstein, On going quality control (e. g. soot test) = Quality Candles which pose no health threat 42

43 Candles have had, have, and will continue to have a very positive image. Enjoy them.

44 The Don t Temple Forget of to Ramses be Proud II with of and Seated Enjoy Colossi your Good of Ramesses Products II at Abu Simbel 44

45 Reference I would like to thank the whole Sasol Wax Candle Team for their support with the preparation of this presentation. Especially: Helmut Gutberlet and Barbara Fertl 45

46 46 Thank you for your attention.