Guide to the safe handling of solvents in a bituminous ... - Aapaq.org

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• A mass balance requires a temperature compensation correctionfactor, which can be determined using a blank. Most commercialovens today have an automatic correction factor built into theapparatus;• A correction factor for moisture within the hot mix asphalt can beobtained by determining the moisture content of a sample of hot mixasphalt.The ignition test has been formalised in AASHTO T308. Themethod is cost- effective and preferable from an HSE point ofview. The method also results in substantial time saving comparedto the solvent extraction method. Proficiency testing conducted inthe USA has found that ignition oven testing results in greaterrepeatability and accuracy than solvent extraction testing 5 . Thisapplies to both the grading of the recovered aggregate as well asthe binder content. Coefficients of variation of less than 2% areobtained for the proficiency testing.Although the growing acceptance of the ignition oven has resultedin a marked decline for the need for solvent extraction methodswhen determining the binder content of HMA mixes, there are stillcircumstances where solvent extractions are necessary:• In cases where aggregates degrade substantially during ignition oventesting and the aggregate after ignition testing cannot be used for agrading determination;• In cases where HMA samples are removed from a site some timeafter construction and no samples are available to determine theappropriate correction factors;• In circumstances where the binder of the hot mix asphalt needs to berecovered and tested.2.1.2.2 SHRP extraction and recovery method: As part of theSUPERPAVE process, an enhanced solvent extraction andbinder recovery method has been developed and designatedas AASHTO T319. The method, developed by Burr et al 6 hasbeen designed to minimise solvent hardening of the binder andto maximise the quantitative extraction of the binder. Extractionis accomplished by using a rotating cylinder, with interior flightsto facilitate mixing of the HMA and solvent. A vacuum line with12
an in-line woven polypropylene filter is used to remove theeffluent, before it passes through a second finer filter system.Any remaining fines in the solution are removed by centrifugeprior to recovery of the binder.This method results in improved repeatability of binderextractions. A coefficient of variation of 6% was obtained forrecovered viscosities compared with a value of 30% 6 attained bythe AASHTO materials reference laboratory proficiency sampleprogramme.2.1.2.3 New solvent developments: In the search for safer andmore environmentally friendly solvents, a number of new solventshave been developed, or alternatively, such solvents have beenintroduced into the bituminous products industry from othersectors in the economy.Solvent developments include:• D-limonene - This is a hydrocarbon (cyclic terpene) obtained bydistilling the oil from orange peels (a by-product from the orange juiceprocessing industry). It is a natural product used in a variety ofapplications, including the cosmetics, food and pharmaceuticalindustry. Limited amounts can be disposed of via the water drainagesystem. Care should be taken when interpreting some of the MSDSfrom Appendix C for these new solvents. The MSDS for D-limonene,for example, classifies it as a major skin irritant (See Appendix C) andhighly poisonous if ingested, yet no toxicity data is available. Theclassification is harsh for a product that is used in medicine, food andmake-up! It is the author's opinion that recent MSDS tend toover-classify (overstate any possible threat, no matter how remote) inorder to protect those authors of the MSDS from any future litigation.With a flash point of 50 o C, D-limonene has a higher fire/explosion riskthan the other new solvents that have entered the market (even ahigher risk than diesel: fp:75 o C).• Florasolvs solvent range - These consist of a range of productsranging from ethoxylated macadamia nut oil to ethoxylated jojoba* oil,which not only serve as solvents, but also as non-ionic surfactants (iesoaps/cleaning agents). They have high boiling points/flash points,resulting in lower fire/explosion-risk materials.13
Page 1: Guide to the safe handling ofsolven
Page 4 and 5: Sabita DVD SeriesDVD100DVD200DVD300
Page 6 and 7: CONTENTS1. Introduction2. Solvent s
Page 8 and 9: • The use of High Performance Liq
Page 10 and 11: 2. Solvent specific test methods2.1
Page 14 and 15: *Jojoba oil (pronounced “ho-HO-ba
Page 16 and 17: properties of the recovered binder.
Page 18 and 19: Table 1. Coefficients of variationM
Page 20 and 21: • Temperature - Although binder h
Page 23 and 24: • Density - In general, a solvent
Page 25 and 26: 2.5. The determination of the softe
Page 27 and 28: 4. Evaluating the cost-effectivenes
Page 29 and 30: 6. Conclusions and recommendationsT
Page 31 and 32: absorptive limestone). In this way
Page 33 and 34: 13. Peterson, GD, Davison, RR, Glov
Page 35 and 36: in a location close to where the pr
Page 37 and 38: product identifier (product name);
Page 39 and 40: eye wash bottles and safety showers
Page 41 and 42: • reaction to naturally-occurring
Page 43 and 44: consulting the MSDS for the product
Page 45 and 46: those which could compromise an ind
Page 47 and 48: • Reactive chemicals May be sensi
Page 49 and 50: The following guidelines should be
Page 51 and 52: mercury air concentrations. If a la
Page 53 and 54: Be prepared to repeat the process i
Page 55 and 56: Leaking regulators, cylinder valves
Page 57 and 58: Peroxide-forming (e.g. ether) and e
Page 59 and 60: • Direct connections: Direct conn
Page 61 and 62: This guide is available on the UK H
Page 63 and 64:
Factors that can increase the risk
Page 65 and 66:
containers that may be contaminated
Page 67 and 68:
Record each run in a logbook: keep
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• Gas chromatographs (GC): Gas ch
Page 71 and 72:
Locate and know how to test and ope
Page 73 and 74:
Do not remove a dressing that has b
Page 75 and 76:
As soon as the flames are extinguis
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Appendix B - Recommendations for so
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• All packages in storage should
Page 81 and 82:
Table 2.Examples of incompatible co
Page 83 and 84:
Table 3. Suggested segregation for
Page 85 and 86:
• Keep picric acid solutions wet
Page 87 and 88:
peroxides. The radius shall be meas
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acute health effect - an effect tha
Page 91 and 92:
8 Corrosive; 9 Miscellaneous.ED50 (
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freezing point - the temperature at
Page 95 and 96:
airborne substance, averaged over a
Page 97 and 98:
teratogen - chemical which may caus
Page 99 and 100:
• Many of the occupation exposure
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