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Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
Influence of using white cement kiln dust as a mineral filler on hot asphalt
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Influence of using white cement kiln dust as a mineral filler on hot asphalt

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  • 1. International Journal of Civil Engineering and TechnologyENGINEERING – 6308 INTERNATIONAL JOURNAL OF CIVIL (IJCIET), ISSN 0976 AND (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEME TECHNOLOGY (IJCIET)ISSN 0976 – 6308 (Print)ISSN 0976 – 6316(Online)Volume 4, Issue 1, January- February (2013), pp. 87-96 IJCIET© IAEME: www.iaeme.com/ijciet.aspJournal Impact Factor (2012): 3.1861 (Calculated by GISI) © IAEMEwww.jifactor.com INFLUENCE OF USING WHITE CEMENT KILN DUST AS A MINERAL FILLER ON HOT ASPHALT CONCRETE MIXTURE PROPERTIES Dr. Talal H. Fadhil*, Salah S. Jasim*, Dr. Kahlil E. Aziz*, Ahmed S. Ahmed * Department of Civil Engineering, Al-Anbar University ABSTRACT The White Cement Kiln Dust (WCKD) as a byproduct material, formed in cement factories during cement production operation, is categorized by Environmental Production Agency (EPA) as a non hazardous solid waste material. In highway construction process, the WCKD can be used in different ways such stabilizing the subgrade soil and also instead of mineral filler in Hot Mix Asphalt (HMA) production which results in more economy and leads to keeping the environment more clean and healthy. In Iraq, there are two common types of fillers that are Portland cement and lime stone powder. In this research, various percentages of WCKD taken from Fallujah cement plant were used in addition to two filler types(100%WCKD, 50%WCKD+50%Cement (C) ,100%C ,50%WCKD+50%Limestone (L), and 100%L to prepare asphaltic concrete mixes. Five tests were used to evaluate the performance of these different asphaltic concrete mixes, standard Marshall Test at 60 OC and 70 OC, to test immersed samples for four days in water at room temperature (24 OC) , Indirect Tensile Strength Test(ITST) to test conditioning and un-conditioning samples. All the test results were acceptable and within the AASHTO and Iraqi roads specifications. The results showed that using WCKD as a filler could conserve the environment and encourage the HMA producers to use this inexpensive material in their works. INTRODUCTION All factories produce, in addition to their main production, different types of waste materials such as acids, alkaline, oils, scrap metal, slag ,fly ash, scrap rubber, stone pieces, powders,..etc. In general, the waste materials are divided into two main types which are hazardous and non-hazardous waste. Non-hazardous industrial wastes are those do not meet the US Environmental Production Agency (EPA)s definition of hazardous waste and are not 87
  • 2. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEMEmunicipal waste [Safe drinking 2012]. The WCKD is also well known as cement kiln dust(ckd) ,as a by-product material formed in cement factory during cement production operation which iscategorized by EPA as a special non hazardous solid waste material [USEPA 2012, Environmentagency2004]. The WCKD is found in the exhaust gasses released by cement kilns and collectedby fabric filters or electrostatic precipitators [Hassan, Jeremy]. The ckd chemical and physicalproperties are influenced by several factors such as, types of kiln feeding process (wet or dry),raw materials, fuel combustion, methods and facilities of dust collections, and others. The generalproperties of ckd are similar to Portland cement [Jeremy2008]. Some of ckd is recycled backagain with the clinker but the amounts are limited by alkalinity requirements for Portland cementand kiln operation issues[Jeremy 2008].However, most of the material is disposed of on-sitewithout any further reusing or reclamation[Hassan2006]. A considered volumetric quantities ofckd are annually generated during cement production. The amount of generated ckd in USA in1995 was 3798000 metric tons; 651000 metric tons of this amount were beneficially reused while3147000 metric tons were sent to landfill. Corresponding quantity was decreased in 2006 to2563000 metric tons ,1403000 metric tons beneficially reused while 1160000 metric tons sent tolandfill due to applying plans and high efforts accomplished by Cement ManufacturingSustainability(CMS) Program [Wayne2008]. In Egypt there were 3million tons [Ayman] and inIraq there were about 640000 tons [Adil 2010]. In addition to the huge amounts of ckd whichare disposed in landfill, the ckd affects human health in three ways : 1- inhalation (lungdiseases) ,2- eyes (eye contact with cement dust) , and 3- skin(irritating effect on most skin).[BsEN 179-1-2012,Hanson2012] Although ckd has negative effects on the environment and human health, it has alsodifferent beneficial uses. For example, uses that need the same action of cementitious property ofcement, in agriculture soil amendment, or in others. Based on literature, some of generalbeneficial ckd uses in highway engineering were found and listed below:1. As a mineral filler in asphalt concrete mixture (fully or partially use )[Ramzi 2002, and FHWA RD-97-148-1998].2. As an agent which can assist in promoting stripping resistance of asphalt concrete mixes (to replace hydrate lime or liquid anti-stripping agents) [Wayne2008, and FHWA RD-97-148]3. CKD can be agglomerated or pelletized to produce artificial aggregates which can be used in special applications to improve the rutting resistance. This type of artificial aggregate can absorb lighter fractions of excess asphalt cement binder during hot weather [FHWA RD-97- 148-1998].4. To stabilize sub-grade soil, granular base, and subbase pavement applications [Tara2010, Joe2003, and Robert 2004].5. To use in flowable fill applications such as in abutment construction, back fill of trenches, as a fill for abandoned pipelines, and in back fill of retaining walls [NCASI 2003, and FHWA RD- 97-148-1998].6. As an asphalt cement modifier by adding ckd to asphalt binder (50/50) to produce a low ductile mastic asphalt. The European use of mastic asphalts, with low ductility for bridge deck water proofing and protection is well documented [Hassan 2006, and FHWA RD-97-148-1998]. The aim of the present work was to: 1- Investigate the possibility of using WCKD as a mineral filler (partially or fully) in producing HMA. 2- Conserve the environment from these huge waste material. 88
  • 3. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEMEMATERIAL PROPERTIES1. Asphalt cementThe 40-50 pen. asphalt cement type was brought from Baiji refinery , about 210km north ofthe capital Baghdad. Standard tests were used to determine its physical properties which areshown in Table (1). 2. AggregatesThe coarse and fine aggregates were supplied from Thumal quarries, about 60 km west ofRamadi city the capital of Anbar province, the aggregate color is white. The midpoint ofsurface course type III A of ISSRB gradation[ISSRB2003], seen in Fig.(1 ) , has beenselected and incorporated in preparing all hot asphalt concrete mixes used in this research.All the mechanical and physical properties of used aggregates have been tabulated inTable (2). Table (1): Physical Properties of Asphalt Cement Asphalt cement grade 40- Test Test Unit 50 ISSRB specifications Result 0.1m Penetration,100gm,5sec,25 OC 40-50 46 m Specific gravity 25 OC /25 OC ---- ---- 1.03 Ductility, 5cm/min., 25 OC cm 100 min. 100+ Solubility in trichloroethylene. % >99 99.1 % Flash point, OC O C 240 min 232+ Residue from thin film oven test Retained % 50 min 71.7 Penetration,100gm,5sec,25 OC. Ductility, 5cm/min., 25 OC. cm 50 min 100+ Table (2): Mechanical and Physical Aggregate Properties ISSRB Coarse agg. Coarse agg. Fine Test ( 12-19)mm (5-12)mm aggregate Los Angeles Abrasion value, < 30 21.6 19.5 ------------ % Bulk Specific gravity 2.609 2.620 2.694 Degree of crushing % > 90 96 97 --------- 89
  • 4. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEME 120 100 80 % Passing 60 upper limit lower limit 40 mid point 20 0 0.01 0.1 1 10 Sieve size (mm) Figure (1): Iraqi road surface course IIIA gradation [ISSRB]3. Mineral Filler Three types of mineral fillers have been used in this study, two of them are commonlyused in Iraq in manufacturing hot asphalt concrete mix which are Portland Cement, broughtfrom Kubaisa Cement Plant 180 km to the west of the capital Baghdad, and the second iscrushed lime stone, from Fallujah city .The third one is WCKD from Fallujah White CementPlant. All the physical specifications of the three types have been examined and found in thelaboratory and shown in Table (3). The chemical compositions of each one can be seen inTable (4). Table (3): Physical Properties of Mineral Fillers Properties % Passing Sieve Size ISSRB& Lime (WCKD) Cement Inches (mm) AASHTO stone No.30 (0.6) 100 100 100 100 No.50 (0.3) 95-100 100 100 100 No.200(0.075) 70-100 94 89.5 97.5 Plasticity Index <4 3.52 1.8 0 Specific gravity --- 2.57 2.93 3.15 Blaine fineness ---- 4770 3630 3400 (cm2/g) 90
  • 5. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEME Table (4): Chemical Compositions of Mineral Fillers Chemical compositions Filler type Loss CaO SiO2 Al2O3 Fe2O3 SO3 Na2O K2O MgO due to ignition (WCKD) 51.96 16.9 4.58 0.4 2.41 0.70 1.12 1.95 19.5 Limestone 51.0 2.7 1 0.16 1.16 --- ---- 1.2 42.6 (L) Cement 62.74 22.68 5.06 3.24 2.2 ---- --- 2.36 1.2 (C)EXPERIMENTAL PROCEDURE In this research, two standard test methods are followed. The first one is Marshall TestMethod, designated as ASTM D1559. It was used to design asphalt concrete mix and to evaluate itsproperties, and the second test is Indirect Tensile Strength Test Method (ITST), designated as ASTMD4123. It was used to find the tensile strength of asphalt concrete mix samples and its fractureresistance. Standard Marshall Specimen, size of 63.5 mm (2.5 inches) height and 101.6 mm (4 inches)diameter compacted 75 blows for each face by Marshall automatic compacter, was used in the twostandard test methods. Five mixtures were prepared and tested. For all types of mixtures, theaggregate gradation and asphalt content (5% weight of total mix) are similar excluding the filler typeand amount which differs from one mix to another as follows (the percentage indicates the filleramount in each mix), 1- 100% WCKD , 2- 100%C, 3- 100% L, 4- 50% WCKD+50% C ,and 5-50% WCKD+50% C.MARSHALL TEST The Marshall Standard Test is executed by immersing the compacted asphalt concretesamples in hot water at standard test temperature of 60 OC for 30 to 40 min.; then applying diametricalloading on samples at rate of 51mm/min. Marshall Test has been applied three times, two of them attwo different temperatures which are 60 OC and the 70 OC. The reason for choosing 70 OC temperatureis due to the hot weather prevalent in Iraq in addition to the thermoplastic property of asphalt cementand its high sensitivity to temperature variation. According to research results that had been appliedon the Iraqi Express Way No.1 from 14/8/1989 to 31/8/1989(Iraqi hottest days in every year) by IraqiState Organization of Roads and Bridges -Resident Engineer Directorate -Part- T9. They found thatthe mean temperature value of asphalt concrete surface course from 12 a.m. to 3 p.m. was 68.88 OC[Tawfeeq A.K.1989] .The third time Marshall test has been executed in case of testing immersedasphalt concrete samples in water at room temperature(24 OC) for four days . The main reason forthe last test was to simulate the effect of water on roadway when it was overflowed for four dayswhich is similar to soaking CBR sample test in the laboratory for 96 hours.Indirect Tensile Strength Test The same Marshall machine has been used to apply a compression load on asphalt concretespecimens at rate of loading 51 mm/min. along a diametrical plane through two opposite loadingcurved strip heads of 12.5mm width. This type of loading leads to perpendicular stress acting onapplied load plane causing the specimen to fail by splitting along the loaded plane. The aim of this testwas to know the resistance of samples to fractures and to determine its tensile strength property. Themaximum load that caused failure was determined and used to calculate the indirect tensile strength. 91
  • 6. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEMEThe ITST was used for two times, one of them for un-conditioning asphalt concrete samples(immersed it in water of 25 OC for one hour) and the other for conditioning samples. The conditioningcase was by immersing samples in hot water of 60 OC for 24 hours and then removing and immersingit in water of 25 OC for one hour and testing it in ITST. The Retained Tensile Strength (RTS) wascomputed by applying the same test procedure namely STP204-15 which had been adopted bySaskatchewan state [STP204-15-2000]. Tensile Strength ( water cured at 60 o C 24hours) % RTS = ×100 Tensile Strength (air cured at 25o C )Marshall Test Results The Marshall test under three different conditions has been applied. The results shown inTable (5) and Figures (2), (3), and (4), are encouraging because they indicate that the properties ofMarshall stability and flow of mixtures having 100%WCKD and other percentages are within theISSRB. Therefore WCKD can be used (fully or partially) as a mineral filler replacement in producingasphalt concrete mixture. In Figure (4) , the air void property of all samples revealed satisfied resultsexcept for samples which contained 100% WCKD and 50% WCKD, they pointed out that their airvoid percentages were larger of about 9.4% and 11.6% respectively than (5%) Iraqi standard upperlimit. This could be attributed to diluting some parts of WCKD in water during the immersing of thesesamples for four days in water. The Marshall Stiffness (MS), stability divided by its flow, is anempirical stiffness value and is used by some engineers, especially in Europe, to evaluate the strengthof asphalt mixture. A higher value of MS indicates a stiffer mixture and, hence, it indicates that themixture is likely more resistant to permanent deformation [Jingna Zhang2003]. MS of mixturesamples had been computed and then compared with MS of the control sample. All the results aretabulated in Table (6). In order to prevent permanent deformation of the mix under high stress, the MSshould not be less than 2.1 kN/mm [Sobhan. M.A.2011]. As shown in Table (6), the MS values aremore than 2.1 kN/mm. except for sample containing 100%L immersed four days in water which gave1.91 kN/mm, the reason for this reduction in MS may has been due to the fact that the sample wasfree from any cementing material like C and WCKD (no setting and hardening can be taken place).Furthermore the lack of cementish property of limestone when it immersed in water resulted in thehighest reading value of flow (5.1mm) and lesser stability reading as compared with the results ofstability and flow of samples immersed in water. Table (5): General Marshall Test Results (ASTM 1559) Stability (kN) Flow(mm) Air voids (%)Test condition at 4 days at at at 60 at 70 4 days in at 60 4 days O O O 70 in 60 70 C C water C O O O in water C water C C ISSRB Min. 8 # # 2- 4 # # 3 -5 # #%100 WCKD 11.9 10.8 12.1 3.7 4.0 4.85 4.95 4.41 5.47 100% C 11.2 10.85 13.8 3.0 3.85 4.75 4.90 3.52 3.76 100% L 9.0 8.1 9.75 3.7 3.75 5.1 4.48 4.28 3.0850% WCKD + 50% C 13.2 10.4 13.4 3.9 3.85 4.6 3.80 4.25 4.0850% WCKD + 14.0 10.2 11.2 4.0 3.95 4.7 4.32 5.01 5.58 50% L ISSRB=Iraqi Standard Specifications for Roads and Bridges, WCKD=White Cement Kiln Dust, C=Cement, L=Limestone, # = No specification 92
  • 7. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEME Table (6): Marshall Stiffness of samples under different test conditions Marshall Stiff. (kN/mm)(60 Marshall stiff. Marshall stiff. O Components C) (kN/mm) (kN/mm)(4days Controlled (70 OC) immersed) Sample 100% WCKD 3.22 2.7 2.49 100% C 3.73 2.82 2.90 100% L 2.43 2.16 1.91 50%WCKD+50% C 3.38 2.7 2.91 50% WCKD+50% L 3.5 2.58 2.38 WCKD=White Cement Kiln Dust, C=Cement, L=Limestone 16 14 12 Stability (kN) 10 8 OC60 at 6 OC70 at 4 2 days in water 4 0 100% C% 100 L% 100 % 50 % 50 WCKD WCKD + WCKD + C50% L50% Figure (2): Stability Values of Mixtures Having Different Components of WCKD 6 5 4 Flow (mm) 3 OC60 at 2 OC70 at 1 days in water 4 0 100% % 100 % 100 % 50 % 50 WCKD C L WCKD WCKD 50% + 50% + C L Figure (3): Flow Values of Mixtures Having Different Components of WCKD 93
  • 8. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEME January ,Figure (4): Percents of Air Voids of Mixtures Having Different Components of WCKD oids omponentsITST test results The ITST results of conditioning and un-conditioning samples and the RTS are unpresented in Table (7) .The mixtures containing 100%WCKD and 50%WCKD he WCKD+50%Cprovided higher values of RTS which are 92.11% and 93.89% respectively .The other results 93.89%, heare lesser but they are still acceptable and within the Iraqi specification value of(70%)[ISSRB2003]. Table (7): The ITST Results of Conditioning and Un-Conditioning Samples esults amples ITST (Un- ITST Retained components conditioning) (Conditioning) tensile (N/cm2) (N/cm2) Strength (%) 100% WCKD 171 157.51 92.11 100% C 165.7 137.23 82.82 100% L 141.5 126.68 89.52 50%WCKD+50% 143.05 134.31 93.89 C 50% WCKD+50% 165.76 130.43 78.68 LCONCLUSIONS AND RECOMMENDATIONS RECOMME The WCKD as a by-product material was tested. The results so produced indicate product testedthat this material had acceptable gradation and other filler specifications and within the tableISSRB and AASHTO M17 requirements. The WCKD was used fully or partially to preparehot mix asphalt samples, these samples were tested by using two standard test methodsfurthermore testing samples under special test conditions such as Marshall test under 70 Cand ran same test for immersed samples. For Marshall test, in general all the stability test test 94
  • 9. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEMEvalues of mixes containing WCKD was increased when they were immersed in water. Thismay be due to setting and hardening parts of WCKD and C. The flow readings were withinthe ISSRB but, in general, for all of the immersed samples they gave more than thespecification and especially for 100%L which gave the highest deviation of about 27.5%more than upper specification limit (4mm) .This result indicate that the use of limestone as afiller was the wariest condition for roads which might be immersed by water. The air voidresults for all samples under three type of test conditions were within the ISSRB except forimmersed samples of 100%WCKD and 50%WCKD+50%L which gave higher than theallowable upper value(5%). For ITST test results, the percentages of retained tensile strengthindicate that all samples were within the ISSRB but the samples of 100%WCKD and50%WCKD+50%C gave the best results of 92.11% and 93.89% respectively.From the above conclusions, it can be recommended that: 1- WCKD can be successfully used as a mineral filler (fully or partially) inproducing hot mix asphalt in addition to conserving the environment from these cheap hugewaste material. 2-Making a trial flexible pavement section by using WCKD as a filler (fully orpartially) in preparing its hot mixture and then studying its behavior for long time underactual traffic motion, and environment conditions.REFERENCES1. Adil N. Abed, Sadoon O. Eyada " the use of cement production waste to improve the properties of hot mix asphalt concrete" 2nd regional conference for engineering science,Al- Nahrain university,Baghdad,2010,p622-634.2. Ayman M. Othman "Incorporation of white cement dust on rubber modified asphalt concrete mixtures" International journal of civil &environmental engineering IJCEE, Vol.9, No. 10, pp.40-51.3. BS EN 179-1 : CEM 1 "Health and safety information, Portland cement" , data sheet, Lafarge cement UK ltd, Birmingham,UK,2012 . http://www.lafarge.co.uk, September20124. Environment agency" Guidance for the recovery and disposal of hazardous and non hazardous waste" integrated pollution prevention and control, IPPC S5.06, issue 4, December 20045. Federal Highway Administration (FHWA) "User guidelines for waste and by‐product materials in pavement Construction" FHWA, RD‐97‐148, April 1998.6. Hanson, Heidelberg cement group" Health and safety data sheet for common cements and cement products" Ketton , Stamford,UK,2009, http://www.hanson.com/uk, September 2012.7. Hassan Y. Ahmad, Ayman M. Othman, and Afaf A. Mahmoud " Effect of using waste as a mineral filler on the mechanical properties of hot mix asphalt", Assiut University. Bull. Environ.Res.Assiut,Agypt,Vol.9,No.1,March 2006.8. ISSRB" Iraqi Standard Specifications for Roads and Bridges", State corporation for roads and bridges, Revised edition2003, Baghdad, 2003.9. Jeremy S. Baugh ,Tuncer B. Edil " Suitability of Cement Kiln Dust for Reconstruction of Roads" Portland Cement Association ,Skokie, Illinois, USA, 2008.10. Jingna Zhang, L.Allen Cooley" Effect of superpave defined restricted zone on hot mix asphalt performance" National Center for asphalt Technology, IR-03-04, Auburn University, November 2003. 95
  • 10. International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 1, January- February (2013), © IAEME11. Joe w. Button," Kiln dust for stabilization of pavement base and subgrade materials" Texas A&M university system, college station, Texas, June 2003.12. National Council for Air and Stream Improvement (NCASI) "Beneficial use of industrial by- products" NCASI, RMT, Inc. working copy, USA, Madison, December 2003.13. Ramzi Taha, Amer Al-Rawas, Ali Al-Harthy ,and Ahmed Qatan "Use of cement bypass dust as filler in asphalt concrete mixtures" Journals of materials in civil engineering, July / August 2002.14. Robert L. parsons, Justin P. Milburn "Use of cement kiln dust for subgrade stabilization", Kansas department of transportation, division of operations, Bureau of materials and research, report No. ks-04-3, final report, October 2004.15. Safe Drinking Water Foundation "Industrial waste ", Canada, http://www.safewater.org June 201216. Sobhan M.A., Mofiz S. A. "Effect of gradation and compactive effort on the properties of bituminous mixes with waste concrete aggregates" international journal of civil &environmental engineering, IJCEE-IJENS ,vol. :11,No. 04.augest 2011.17. Standard test procedure manual (STP204-15) "Stripping potential and splitting tensile strength" STP204-15, Asphalt mixes, Saskatchewan highways and Transportation, 2000.18. Tara Sen , Umesh Mishra" Usage of Industrial Waste Products in Village Road Construction" International Journal of Environmental Science and Development, Vol. 1, No. 2, June 2010.19. Tawfeeq A.K. "Study of asphalt surface temperature" Expressway resident engineer directorate part t9, State Organization of roads and bridges, Ramadi, Iraq, 1989.20. USA Environmental protection agency "Industrial waste guidelines, Non hazardous waste", http://www.epa.gov/waste/nonhaz/industrial/index.htm, June 201221. Wayne S. Adaska, Donald H. Taubert " Beneficial uses of cement kiln dust ", PCA 50thcement industry technical conference, Miami, FL, May 2008. 96

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