heavy metal content and leaching potential of recycled glass beads used in pavement markings

147 Pages·2011·10.22 MB·English

HEAVY METAL CONTENT AND LEACHING POTENTIAL OF
RECYCLED GLASS BEADS USED IN PAVEMENT MARKINGS

by

Bryan Boulanger, Ph.D.
Assistant Professor
Environmental & Water Resources Engineering Division
Zachry Department of Civil Engineering
Texas A&M University

Aditya Babu Raut Desai, Ph.D.
Post-Doctoral Research Associate
Environmental & Water Resources Engineering Division
Zachry Department of Civil Engineering
Texas A&M University

and

Paul Carlson, Ph.D., P.E.
Research Engineer
Texas Transportation Institute

Project Title: Heavy Metal Content and Leaching Potential of Recycled Glass Beads
Used in Pavement Markings

April 1, 2011

TEXAS TRANSPORTATION INSTITUTE
The Texas A&M University System
College Station, Texas 77843-3135
DISCLAIMER

The contents of this report reflect the research conducted by the authors who are
responsible for the facts and the accuracy of the presented data. This report does not
constitute a standard, specification, or regulation. Mention of trade names or
commercial products does not constitute an endorsement or recommendation for use.
The researcher in charge of the project covered in this report was Dr. Bryan Boulanger
of Texas A&M University’s Zachry Department of Civil Engineering.
ii
ACKNOWLEDGMENTS

Completion of this research would not have been possible without the following
individuals whom we gratefully acknowledge.
• Dr. William James from the Center for Chemical Characterization at Texas
A&M University (TAMU) for helping with X-Ray Fluorescence.
• Tom Stephens from TAMU’s Microscopy and Imaging Center for assistance
with the scanning electron microscope.
• Brad Beless, Dr. Pranav Nagarnaik, and Ishan Desai from the Boulanger
Research Group for their help and advice in research design, data
acquisition, and data interpretation.
• All the support staff at the Texas Transportation Institute and the Zachry
Department of Civil Engineering for their help in project administration.
iii
TABLE OF CONTENTS
Page
List of Figures .................................................................................................................................. vi
List of Tables ................................................................................................................................. viii
List of Units ..................................................................................................................................... xv
1. Project Introduction ............................................................................................................. 1
2. Materials, Analytical Methods, and Experimental Procedures ................................... 3
2.1. Recycled Glass Beads ................................................................................................. 3
2.2. Reagents ....................................................................................................................... 3
2.3. X-Ray Fluorescence (XRF) Sample Analysis .......................................................... 4
2.4. Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy
(EDS) Sample Analysis .............................................................................................. 4
2.5. Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) Sample Analysis .. 5
2.6. Potassium Hydroxide Fusion Procedure ................................................................ 5
2.7. Bead Rinsing Procedure ............................................................................................ 6
2.8. Column Experimental Procedure ............................................................................ 7
2.9. Ultraviolet (UV) Light Bead Exposure Procedure ................................................. 9
2.10. Bead Temperature Exposure Procedure ................................................................. 9
2.11. Bead Abrasion Procedure .......................................................................................... 9
2.12. Quality Assurance/Quality Control ....................................................................... 10
2.13. Data Analysis and Presentation ............................................................................. 11
3. Results and Discussion ..................................................................................................... 14
3.1. QA/QC ....................................................................................................................... 14
3.2. Experiment 1: Evaluation of Heavy Metal Composition in Bulk Bead
Samples ...................................................................................................................... 15
3.3. Experiment 2: Effect of Solution pH on Metal Leaching from Recycled
Glass Beads ................................................................................................................ 18
3.4. Experiment 3: Effect of UV Light Exposure on Metal Leaching from
Recycled Glass Beads ............................................................................................... 24
3.5. Experiment 4: Effect of Temperature on Metal Leaching from Recycled
Glass Beads ................................................................................................................ 26
3.6. Experiment 5: Effect of Abrasion on Metal Leaching from Recycled Glass
Beads........................................................................................................................... 28
4. Conclusions and Recommendations .............................................................................. 31
References ........................................................................................................................................ 37
iv
Appendix A: QA/QC Reviewed Data Used to Determine Method Detection Limits ...... 38
Appendix B: Surface Visualization and Bulk Composition using SEM-EDS ................... 41
Appendix C: Rinsing Study QA/QC Reviewed data .............................................................. 62
Appendix D: Column Study QA/QC Reviewed Data ............................................................ 66
v
LIST OF FIGURES
Page

Figure 2.1. Experimental setup for upflow column leaching system. ...................................... 8
Figure 3.1. Mean arsenic and Σ(heavy metals) content in sponsor provided recycled
glass beads. .................................................................................................................. 18
Figure 3.2. Characteristic leaching profile observed during column study.. ......................... 21
Figure 3.3. pH Effect on mean arsenic and ∑(heavy metals) leaching from Batch 1
beads. . ......................................................................................................................... 23
Figure 3.4. pH effect on mean arsenic and ∑(heavy metals) leaching from Batch 3
beads. ............................................................................................................................ 24
Figure 3.5. UV exposure effect on mean arsenic and ∑(heavy metals) leaching from
Batch 1 beads. .............................................................................................................. 25
Figure 3.6. UV exposure effect on mean arsenic and ∑(heavy metals) leaching from
Batch 3 beads. .............................................................................................................. 26
Figure 3.7. Temperature exposure effect on mean arsenic and ∑(heavy metals) leaching
from Batch 1 beads. .................................................................................................... 27
Figure 3.8. Temperature exposure effect on mean arsenic and ∑(heavy metals) leaching
from Batch 3 beads. .................................................................................................... 28
Figure 3.9. Effect of abrasion on mean arsenic and Σ(heavy metals) leaching from Batch
1 beads. ......................................................................................................................... 29
Figure 3.10. Effect of abrasion on mean arsenic and Σ(heavy metals) leaching from Batch
3 beads. ......................................................................................................................... 30
Figure 4.1. Mean heavy metal content in sponsor supplied recycled glass bead. ................. 35
Figure 4.2. Mean heavy metal content leached into rinsing solution. ..................................... 36
Figure 4.3. Mean heavy metal content released into pH 7 solution during the 48 hour
column leaching studies. ........................................................................................... 36
vi
Figure B.1. SEM image of slide with glass beads (Batch 1) ....................................................... 42
Figure B.2. SEM image of three black-colored imputrities (Batch 1) ....................................... 42
Figure B.3. SEM image identifying location of impurities on surface of bead (Batch 1). ..... 43
Figure B.4. SEM image and EDS spectrum of surface impurity on glass bead (Batch 1). .... 44
Figure B.5. SEM image and EDS spectrum of black-colored impurity (1):Figure B.2. ........ 45
Figure B.6. SEM image and EDS spectrum of black-colored impurity (2):Figure B.2. ........ 46
Figure B.7. SEM image and EDS spectrum of black-colored impurity (3: Figure B.2. ......... 47
Figure B.8. SEM image of slide with glass beads (Batch 2). ...................................................... 48
Figure B.9. SEM image of impurity attached to glass bead (Batch 2). ..................................... 49
Figure B.10. SEM image of fused glass beads (Batch 2)............................................................. 49
Figure B.11. SEM imageof surface impurities on a glass bead (Batch 2). ............................... 50
Figure B.12. SEM image and EDS spectrum of surface impurity (1) on Batch 2 bead ......... 51
Figure B.13. SEM image and EDS spectrum of surface impurity (2) of bead (Batch 2) ....... 52
Figure B.14. SEM image and EDS spectrum surface impurity on glass bead (Batch 2) ....... 53
Figure B.15. SEM image and EDS spectrum of area around surface impurity (Batch 2) ..... 55
Figure B.16. SEM image and EDS spectrumof surface impurity on glass bead (Batch 2) .... 56
Figure B.17. SEM image of slide with glass beads (Batch 3). .................................................... 57
Figure B.18. SEM image of impurity attached to glass bead (Batch 3). ................................... 58
Figure B.19. SEM image of fused glass beads (Batch 3)............................................................. 59
Figure B.20. SEM image of crystalline needle-shaped glass (Batch 3). ................................... 60
Figure B.21. SEM image of fused glass beads (Batch 3)............................................................. 61
vii
LIST OF TABLES
Page

Table 2.1. Particle size distribution and calculated specific surface area of abraded
beads. ............................................................................................................................ 10
Table 2.2. Layout of the experimental design. ........................................................................... 12
Table 3.1. Method Detection Limit for ICP-MS analysis. ......................................................... 14
Table 3.2. Mean ± standard deviation heavy metal content in sponsor provided recycled
glass beads. .................................................................................................................. 17
Table 3.3. Mean ± standard deviaiton heavy metal content in the neutral pH rinse
solutions per mass of rinsed beads. ......................................................................... 20
Table 3.4. Mean ± standard deviation mass of metals leached per mass of beads in pH 7
solution. ........................................................................................................................ 23
Table 4.1. Mean ± standard deviation arsenic content in bulk beads, the rinse solution,
and the pH 7 leaching solution. ................................................................................ 32
Table 4.2. Mean ± standard deviation cadmium content in bulk beads, the rinse
solution, and the pH 7 leaching solution. ............................................................... 33
Table 4.3. Mean ± standard deviation chromium content in bulk beads, the rinse
solution, and the pH 7 leaching solution. ............................................................... 33
Table 4.4. Mean ± standard deviation copper content in bulk beads, the rinse solution,
and the pH 7 leaching solution. ................................................................................ 34
Table 4.5. Mean ± standard deviation lead content in bulk beads, the rinse solution, and
the pH 7 leaching solution. ....................................................................................... 34
Table 4.6. Mean ± standard deviation nickel content in bulk beads, the rinse solution,
and the pH 7 leaching solution. ................................................................................ 35
Table A.1. Determination of background instrument response for eight blanks. ................. 39
Table A.2. Data used to determine Method Detection Limit (MDL). ...................................... 40
viii
Table C.1. Bead rinsing (Batch 1). ................................................................................................. 63
Table C.2. Bead rinsing (Batch 2). ................................................................................................ 64
Table C.3. Bead rinsing (Batch 3). ................................................................................................ 65
Table D.1. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
4, Repetition 1 .............................................................................................................. 67
Table D.2. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
4, Repetition 2 .............................................................................................................. 68
Table D.3. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
4, Repetition 3 .............................................................................................................. 69
Table D.4. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
7, Repetition 1 .............................................................................................................. 70
Table D.5. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
7, Repetition 2 .............................................................................................................. 71
Table D.6. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
7, Repetition 3 .............................................................................................................. 72
Table D.7. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
10, Repetition 1 ............................................................................................................ 73
Table D.8. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
10, Repetition 2 ............................................................................................................ 74
Table D.9. Concentration of heavy metals in leachate from glass beads (Batch 1) at pH
10, Repetition 3 ............................................................................................................ 75
Table D.10.Concentration of heavy metals in leachate from glass beads (Batch 1) kept at
100 °F for 24 hours, Repetition 1 ............................................................................... 76
Table D.11.Concentration of heavy metals in leachate from glass beads (Batch 1) kept at
100 °F for 24 hours, Repetition 2 ............................................................................... 77
Table D.12.Concentration of heavy metals in leachate from glass beads (Batch 1) kept at
100 °F for 24 hours, Repetition 3 ............................................................................... 78
ix
Table D.13.Concentration of heavy metals in leachate from glass beads (Batch 1) kept at
150 °F for 24 hours, Repetition 1 ............................................................................... 79
Table D.14.Concentration of heavy metals in leachate from glass beads (Batch 1) kept at
150 °F for 24 hours, Repetition 2 ............................................................................... 80
Table D.15.Concentration of heavy metals in leachate from glass beads (Batch 1) kept at
150 °F for 24 hours, Repetition 3 ............................................................................... 81
Table D.16.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 12 hours, Repetition 1 .............................................. 82
Table D.17.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 12 hours, Repetition 2 .............................................. 83
Table D.18.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 12 hours, Repetition 3 .............................................. 84
Table D.19.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 24 hours, Repetition 1 .............................................. 85
Table D.20.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 24 hours, Repetition 2 .............................................. 86
Table D.21.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 24 hours, Repetition 3 .............................................. 87
Table D.22.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 48 hours, Repetition 1 .............................................. 88
Table D.23.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 48 hours, Repetition 2 .............................................. 89
Table D.24.Concentration of heavy metals in leachate from glass beads (Batch 1)
exposed to UV radiation for 48 hours, Repetition 3 .............................................. 90
Table D.25.Concentration of heavy metals in leachate from glass beads (Batch 1)
abraded to size between 149 and 250 micron , Repetition 1 ................................. 91
x