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Materials Characterization of Unknown Wastewater Samples from Tyndall Air Force Base

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Materials Characterization of Unknown Wastewater Samples from Tyndall Air Force Base
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Konstantis, Tatiana Kristin
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Tyndall Air Force Base located near the Panhandle of Florida has recently incurred a handling problem of an unknown substance present within wastewater stemming from Mexico Beach, Florida. This unknown substance has an oily appearance, an unusual buoyancy when heated, and "grows" when exposed to drying conditions. The objective of this research is to apply materials science analytical techniques to an environmental engineering problem occurring in industry by characterizing this substance. Samples received from Lift Station #1722 have been analyzed using Optical and Scanning Electron Microscopy, Energy Dispersive Spectroscopy, and Fourier Transform Spectroscopy. The original hypothesis contributed the substance to breakdown effects of flushable consumer products on the market, however, results indicate that the substance could be potential plant matter. ( en )
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Awarded Bachelor of Science in Materials Science and Engineering, magna cum laude, on May 8, 2018. Major: Materials Science and Engineering
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College or School: College of Engineering
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Advisor: Matthew Zaluzec. Advisor Department or School: Materials Science and Engineering

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University of Florida
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University of Florida
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Copyright Tatiana Kristin Konstantis. Permission granted to the University of Florida to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.

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1 Materials Characterization of Unknown Wastewater Samples from Tyndall Air Force Base Tatiana Konstantis PI: Dr. Katrina Indarawis Honors Thesis Abstract Tyndall Air Force Base located near the Panhandle of Florida has recently incurred a handling problem o f an unknown substance present within wastewater stemming from Mexico Beach, Florida. This unknown substance has an oily appearance, an unusual buoyancy when heated, and The objective of this research is to apply materials science analytical techniques to an environmental engineering problem occurring in industry by characterizing this substance. Samples received from Lift Station #1722 have been analyzed using Optical and Scanning Electron Microscopy, Energy Dispe rsive Spectroscopy, and Fourier Transform Spectroscopy. The original hypothesis contributed the substance to breakdown effects of flushable consumer products on the market however, results indicate that the substance could be potential plant matter. I ntroduction Tyndall Air Force Base, located in the Panhandle of Florida, treats wastewater produced from nearby cities such as Mexico Beach. This wastewater travel s from a lift station on Canal S treet in Mexico B each to Tyndall Air Force B ase (TAFB) as see n in Figure 1 The wastewater is directed 3 miles up the coast in 14 inch pipes near Highway 98. The pipe leaving the Mexico Beach lift station is made out of PVC and connects with anothe r 14 inch ductile iron pipe Wastewater received from the region depi cted in Figure 2 contains an unidentifiable substance that has out. The substance also has unusual wastewater characteristics as it is oily in appearance, has a brown color, potent smell, and is less dense than water in warmer conditions. Experienced workers within this region have not previously identified a substance like this before and are u ncertain of what is causing it as pipe flow calculations indicate tha t flow rates are not potentially affected. Evidence of fibrous material can be seen from visual inspe ction as indicated in Figure 2. Figure 1. Map and location of lift stations and pipes flowing wastewater to TAFB

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2 Figure 2. Left: Wastewater samples from Lift Station #1722; Right: Remaining substance after being filtered Wastewater is the water used resulting from residential, commercial, or industrial proces ses. Variations in wastewater compositions are not significant across regions. O dors are contributed to the decomposition of organic matter where increases in unpleasant odors are mainly attributed to septic and stale wastewater. Fresh wastewater is typica lly gray while septic wastewater is typically black. Inorganic chemical s commonly present are chloride binding materials, alkalinity causing compounds and traces of iron. High concentrations of organic compounds are expected to be present containing elemen ts such as sulfur, phosphorus, nitrogen, oxygen, carbon, and hydrogen. Proteins are found to make up the bulk of t he organic matter present followed by carbohydrates, fats, and oils with the latter two being less than 10% present [1] Mexico Be ach is a t ourist city with its largest industries being retail trade, healthcare and social assistance, and public administration [ 2] There are no current industrial manufactures present within the city who disposed of heavy metals however, over the last 5 years t he city has undergone major infrastructure changes such as the replacement of metal wastewater pipes to PVC pipes as well upgrades on the city canal. A neighboring pulp plant previously owned by Arizona Chemical Holdings Corp. w as bought out by Kraton Perf ormance Polymers In. in early 2016 [3] Recent advances within the non woven flushable fabric industry have designed and produced products currently on the market that have shown physical evidence of breakdown and dispersion within several minutes of agi tation. As of 2015 these products have accumulated $1.4 billion in sales as well as 55,720 tons of wipes used [4] As previously mentioned, wastewater is composed of roughly 10% of fats and oils [1] When these oils bind to other constituents present within wastewater they agglomerate to form what is commonly known as a fatberg shown in Figure 3 Due to recent industry modifications and the visual fibrous appearance of the samples in Figure 2 it is hypothesized that these flushable products are the unknow n substance present within the TAFB sa mples. Oils present would be contributed to food and grease disposed of in kitchen sinks. These oils would agglomerate with dispersed particles causing the buoyancy of the unknown matter. The growth would be contribute d to the combination of particulates drying out with the presence of microbials and organic matter housed within the matter and would contribute to the smell where retention of human waste leaches to these fibers. Since industry modifications are recent, a lack of recognition of wastewater field members would be present. Figure 3 Image of traditional fatbergs found within w astewater [5 ]

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3 Figure 4. Hazen Williams Coefficient Equation [6] Theory : In order to determine if flow rates are affected from the Hazen Williams Equation as shown in Figure 4 back calculations of the roughness coefficient, C, are compared to standar d values based on pipe material and age Input values of the equation are pressure, flow rate, and the internal pipe diameter received from data collected at the site. Although this is an empirical equation it has shown to verify deficient pipes within the field. C values back calculated below that of the expected values indicate a decrease in flow rates than that expected. The C value calculated for the pipes used within this region, 115, were above the expected 110, indicating that flow rates within the p ipes are not currently significantly affected. Further analysis of these rates however, need to be conducted as the pipe material changes within the three mile flow run. Materials and Methods Wastewater samples were collected from Tyndall Airfo rce Base Lift station #1722 and were stored in 4C conditions Wastewater samples were also collected from the U niversity of F lorida Reclamation Center to represent a traditional wastewater standard comparison and were stored in the same conditions. The UF campus can be considered a mirco city as it services residential living for students, industry with the conduction of research within campus labs, businesses from campus office spaces and continual building construction. Flushable m arket products were researc hed and compiled based upon labeling indicating product flushability. The three final products, Scrubbing Bubbles Antibacterial Bathroom Flushable Wipes, Cottonel le Flushable Cleansings Cloths, and Air WickV.I. Poo Toilet Perfume were selected from this li st based off of similar ingredients, breakdown ability, and industry standard technology. Agitation e xperiments to simulate wastewater pipe interaction, consisted of placing one wipe in a beaker with tap water were it was agitated for 24 hours. The perfum e product was sprayed 3 times over approxima tely 9 grams of toilet paper placed within a beaker of tap water and was also agitated for 24 hours. Two batches of each product were tested, one in a shaker table at 200 rmp and the other with a magnetic stir b ar at a medium setting. Samples received from shaker table agitated results minus the Scrubbing Bubbles product along with both wastewater samples were then freezed dried in a Labconco Freeze Dryer for 24 hours. Optical images of these samples were take n with an Olympus Microscope and product images were colored contrasted in ImageJ to further distinguish fiber contrast. Fourier Transform Infrared Spectroscopy Attenuated Total Reflectance (FTIR ATR) was then completed on all freeze dried samples using a diamond crystal on a Nicolet 6700 FTIR Spectrometer. Samples were then mounted to stubs and gold sputter coated with a minimum of 200 angstroms of Au using a Denton Vacuum Desk II Sputter Coater. Mounting techniques followed that as if working with powered samples, where samples were placed on carbon tape adhered to the sub a nd then sprayed with Dust Off compressed gas duster Coated samples underwent Scanning Electron Microscopy (SEM) in conjunction with Energy Dispersive Spectroscopy (EDS) on a PhenomPro SEM system.

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4 Figure 5. Magnetic stir agitation of Left: perfume with toilet paper; Right: Cottonelle Cloth Results and Discussion Agitation Results Of the three products tested in an agitated environment, only two showed significant breakdown, the toilet paper with V.I. Poo Perfume and Cottonel le Cloth. As shown in Figure 5 product breakdown r esulted in a cloudy aggregated material specifically for the Cottonelle Cloth Breakdown for this product was observed to occur within the first 5 minutes of agitation from the magnetic stir bar. The Scrubbing Bubbles Antibacterial Bathroom Flushable Wipes showed no evidence of break down in both agitated settings and was therefore no longer used in experimentation beyond this point since the unknown substance visual ly indicates that some form of dispersion has occurred Table 1 summarizes product breakdown tested with each method. Breakdown of the Cottonelle Cloth and its cloudy puffy appeara nce verifies flushable label claims, however, the results of the Scrubbing Bubbles Wipes indicate that there are still products on the market that do not scientifically meet these claims. Products of this fiber composition can be eliminated as a potential substan ce in the TAFB wastewater samples as products that do not breakdown have shown to create stoppages in mainframe pipes and have to be physically removed in order to obtain proper pipe flow. As mentioned, the pipe flow in the sample region has maintai ned proper flow rates and has not experienced stoppages caused by a result of lack of breakdown. Wastewater samples received show evidence of broken fibers in Figure 2 Since both toilet paper and Cottonelle Cloths experience d breakdown, they were used for further experimentation. Optical and SEM Imaging Optical microscopy of wastewater samples indicated that a type of non woven fabric product or multiple products where present within both wastewater samples. The TAFB samples, however, where optically dar ker than that of the UF Reclamation wastewater samples as see n in Figure 6 The non woven fiber sizes did not visually appear to differentiate themselves besides that of a slight difference in color. Direct fiber sizes of each sample could not be determine d based off of optical microscopy due to image changes in field of depth. In order to further determine what type of non woven fabrics where present, SEM was needed. Product Shaker Breakdown Magnetic Stir Breakdown Air Wick Perfume & Toilet Paper No Yes Cottonelle Cloths Yes Yes Scrubbing Bubbles Wipes No No Table 1. Agitation experimentation results

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5 SEM imaging further verified that a form of non woven fibers where p resent within TAFB wastewater samples, however, other existing structures were also present besides that of non woven fibers. Thi s can be seen in the Figure 7 where fibers encased in a blue oval vary structurally than that of existing material around it w hich would be classified as the potential unknown substance. Comparing both wastewater samples to the created non woven fiber samples allows for structural and topographical indications as to what non woven fibers should look like when present within waste water samples. UF Reclamation wastewater samples verify this conclusion as similar magnifications indicate that there is a higher concentration of non Figure 6 Optical magnifications of a) Tyndall Air Force Base wastewater sample b) UF Water Reclamation wastewater sample c) perfume and toilet paper sample d) Cottonelle Cloth sample a) b) c) d) a) b) c)

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6 Figure 7 a propo ses the question as to whether the unknown material next to intact non woven fibers is shredded or destroyed non woven fibers SEM images of the non woven fiber samples, however, reveal that destroyed fibers have a tendency to break apart leaving shredded material and elongated holes. When comparing non woven fibers topographically, toilet paper samples have a smoother topography than that of the Cottonelle Cloth. Figure 8. Non woven fiber SEM images: a ) Toile t Paper with perfume breakdown b) Cottonelle Cloth breakdown When comparing these non woven fiber images to that of TAFB images, diff erences in structure, shape, and size are evident Non woven samples indicate dense bulk materials without the absence of pores unlike that of the TAFB samples whose structures are not very uniform. Non woven structures are also more homogenous in rect angular shape and size as they fall in a range of approximately 20 50 a ) b ) Figure 7. SEM image of all four samples. a/b) TAFB c) UF R eclamation d) Toilet Paper with V.I. Poo Perfume e) Cottonelle Cloth d) e)

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7 than that of the non woven fibers. Another unique aspect of the TAFB samples is that their porosity allow for the presence of imbedd ed structures seen in Figure 9 Inconsi stency of imbedde d content and its organization indicates possible ma n made materials. In Figure 9 three stacked plate like materials with sharp co rners measuring in size of 26 support man made contaminants. Other unusual imbedded content include a hone y comb like material that is also obs erved as depicted in the Appendix Evidence of cells and plan t life can be seen in Figure 10 If plant matter is present then then unidentified embedded struc tures seen above can an organized system produced by nature. As mentioned previously, when comparing the UF Reclamation wastewater samples that that of the TAFB samples, there is a distinct difference between the concentrations of non woven fibers pres ent across the two samples. Other distinguishing characteristics include a string like pulling of material between the walls and porosity seen in the TAFB samples that are not seen in the UF samples. Instead the UF samples have stick like figures present a t the interfaces of walls and components are made of dense structures representing that of what was seen in the non woven fabric samples. Figure 10. SEM image of TAFB plant cells Figure 9. Imbedded structures in TAFB samples Left: honeycomb; Right: stacked plates and tubes a) b)

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8 EDS EDS results of non woven fiber samples were expected to have high concentrations of elements such as carbon, oxygen, and nitrogen due to the organic nature of these products, followed by a low concentration of go ld as these samples were gold sputtered. As seen in Table 2 expectations were confirmed with no additional elements present. Wastewater sample results also indicated high concentrations of carbon, oxygen, and nitrogen, however, other various elements we re present as indicated in Table 3 The presence of Si and Al in the TAFB samples could be attributed to various types of sand as Mexico Beach is loca ted off the Gu lf of Mexico Plants, however, also con tain elements such as Si and P. Elements such as Cl, Mg, Ra, and Au that were present within the UF samples were expected to be seen within the TAFB as these are elements that are traditionally found within tap and wastewater are contaminated human byproducts, and in sample coating. Their lack of detection in the TAFB samples could be due to the high concentrations of organic content present. Absence of heavy metals such as lead, mercury, and cadmium allow for ruling out of illegal dumping from neighboring industries Further research will investigate the po ssibility of local agri business or industrial plant pulp processing operations in the general vicinity as a potential source or organic plant materials entering the waste stream. Overall, EDS results reveal that there was not a significant elemental diffe rentiation across all samples. Samples Elements Toilet Paper/Perfume Carbon, Oxygen, Nitrogen, Gold Cottone lle Cloth Carbon, Oxygen, Nitrogen, Gold Figure 11. a) TAFB i nterface at holes b) TAFB porous structure c) UF interface at hole d) UF dense structure Table 2. EDS results of non woven fiber samples Figure 12. EDS spot analysis of wastewater samples Left: TAFB; Right: UF c) d)

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9 Table 3. ED S results of wastewater samples Samples Spot Elements TAFB 1 C, O, N 2 C, O, S, N, P, Si, Al 3 C, O, Ca, Si 4 C, O, N, Ca, S, Si, P, Al UF Reclamation 1 C, O, N, Au, Cl 2 C, O, N, Au, Ca, Cl, P 3 C, O, Au, Ca, S, Si, P, Br, Mg, Sn 4 C, O, N, Au, Ra, Cl FTIR FTIR results of the non woven fabric samples revealed two main peak differences when co mpared to each other in Figure13 at the wavelengths 1730 cm 1 and 1240 cm 1 The wastewat er samples also had two distinct main peak differences when looking at the entire spectrum with the TAFB samples having a higher overall absorbency than that if the UF samples. The overall bonding and their corresponding peaks of the TAFB sample can be see n in Figure 16 followed by Table 4 Figure 14 FTIR of non woven fibers Figure 15. FTIR of wastewater samples Figure 16. FTIR of TAFB sample

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10 In order to determine the finger print of the unknown sample, fingerprints and peaks of substances expected to be in the TAFB sample where compared to back track out what the peaks of the unknown substance may be. Since all four samples had concentrations of non woven fabric content, fingerprints of cellulose and hemicellulose were compared across all sa mples as in dicated in Figure 17 Cellulose is expected to be found in the t oilet paper, Cottonelle Cloth, and UF samples as these products are paper based and their finger prints should indicate cellulose. Hem icellulose is commonly present in decaying plants and lacks three distinct peaks from that of cellulose. As indicated by the oval in the figure from the wavelength range of 950 to 1200 cm 1 all four samples have the traditional cellulose fingerprint, with each peak from 1030 to 1150 cm 1 overlapping e ach other. When looking from 1250 to 1400 c m 1 the non woven fabrics and the UF samples have three peaks side by side, while the TAFB sample does not. As mentioned previously, the three peaks are specific to cellulose while the absence of th e peaks with addition Chemical Bond Typical Peak Range Tyndall Peaks O H (H bonded) 3550 3200 (cm 1 ) 3280 (cm 1 ) C=O 1670 1820 (cm 1 ) 1730 (cm 1 ) C O 1050 1150 (cm 1 ) 1031 (cm 1 ) C=C 1 ) 1629 ( cm 1 ) N O 1515 1560 & 1345 1385 (cm 1 ) 1538, 1376, 1335 (cm 1 ) Table 4. TAFB bonding and respective peaks Figure 17. FTIR of cellulose and hemicellulose fingerprints across the four samples

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11 of the 950 1200 cm 1 peak range is specific to hemicellulose. This therefore, leads to the conclusion that the unknown substance can potentially be some type of plant derivative. Fin gerprint wavelengths of urea, which is a byproduct of urine breakdown, reveal that peak regions on the TAFB samples are not peaks from the unknown substance. Data supporting this and the following other fingerprints are located within the appendix section. Traditional components of wastewater contain less than 10% of oils, but as mentioned the unknown substance was oily in appearance and less dense than that of water. Oils specifically used within cooking, such as extra virgin olive oil, where compared to Tyndall samples and showed that they Tyndall samples had characteristic peaks of oil in high concentrations. This is noted with the two large peaks seen in the 2700 3000 cm 1 range. Since Si was detected in EDS, fingerprints of sand were compared to the Tyndall samples, however, peaks do not strongly standout and some overlap with substances identified previou sly such as cellulose peak s at 1158 and 1050 cm 1 When looking into the peer li terature on plant matter, the fingerprint of papaya leafs and flowers, visually showed large similarities to that of the Tyndall samples. Further analysis revealed the greatest amount of peak overlaps seen thus far with consistent peaks found in both the leaf and flower of the plant. While it is not believed that the unknown matter is specifically derived from a papaya plant, the similarities in fingerprint regions further justi fy the potential of the unknown substance to be some form of plant matter. From the above results, a new hypothesis of the unknown substance was formed contributing it to the potential breakdown of plants entering into infrastructure. This new hypothesis can be supported by the fact that oils are present within plant residue and that large natural organic matter is less dense than water, explaining the oily appearance and buoyancy of the unknown substance. Plant matter has the presence of organic cellular structures that have the tendency to cake onto substances, which would explain the unexpected growth of the substance when drying out. The smell of the unknown matter could be contributed to the release of sulfur and phosphorus from plant decay which woul d also contribute to the color of the substance. Environmental factors, such as the occurrence of two hurricanes after a lapse within the past ten years, affecting infrastructure could contribute to the lack of recognition by regional workers. Conclusion Wastewater samples received from Tyndall Air Force Base containing an unknown substance were predicted to be the result of dispersed non wo ven fabrics, excluding toilet paper, that are flushable. Materials science techniques used to investigate this hypo thesis revealed that non woven fibers are present within Tyndall Air Force Based samples, however, these fibers are not contributing to the unknown substance as revealed through SEM imaging and FTIR analysis. Results indicate that the unknown substance cou ld be plant matter, however, in order to test this future work is nee d. Future work would comprise replicating samples with plant matter, further specifying FTIR analysis, and collecting water quality data. Further characterization of present organ ic matte r is also needed as well investing production processes of the neighboring pulping plant.

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12 References [1] S. Muttamara, "Wastewater Characteristics", Resource, Conservation, and Recycling no. 16, pp. 145 159, 1996. [2] "Mexico Beach, FL", Data USA 2018. [Online]. Available: https://datausa.io/profile/geo/mexico beach fl/#economy. [Accessed: 22 Apr 2018]. [3] "Arizona Chemical agrees to $1.37 billion buyout by Kraton Performance Polymers | Jax Daily Record | Financial News & Daily Record Jackson ville, Florida", Financial News & Daily Record Jacksonville, Florida 2018. [Online]. Available: https://www.jaxdailyrecord.com/article/arizona chemical agrees 137 billion buyout kraton performance polymers. [Accessed: 22 Apr 2018]. [4] B. Wipes, "Flu shable Wipes Market & Trends | News | Smithers Pira", Smitherspira.com 2018. [Online]. Available: https://www.smitherspira.com/resources/2014/january/briefing the next steps for flushable wipes. [Accessed: 12 Mar 2018]. [5] "Monster Fatberg Goes On Dis play at London Museum". [Online]. Available: https://www.smithsonianmag.com/smart news/monster fatberg goes display london museum 180968137/ [6] U. Equation, "Understanding the Darcy Weisbach Equation Sprinkler Age", Sprinkler Age 2018. [Online]. Availa ble: https://sprinklerage.com/understanding darcy weisbach equation/. [Accessed: 03 Apr 2018]. [7] "IR frequencies". [Online]. Available: http://www2.ups.edu/faculty/hanson/Spectroscopy/IR/IRfrequencies.html. on of cellulose and hemicellulose by using alkaline peroxide", Natural and Engineering Sciences vol. 2, no. 2, pp. 100 110, 2017. [9] Z. Piasek and T. Urbanski, "The Infra red Absorption Spectrum and Structure of Urea", BULLETIN E \ E L'ACADEMIE POLONAISE D ES SCIENCES Serle des sciences chimlques vol. 10, no. 3, 1962. [10] M. Guillen and N. Cabo, "Infrared spectroscopy in the study of edible oils and fats", Journal of the Science of Food and Agriculture vol. 75, no. 1, pp. 1 11, 1997. [11] "Sand Database of ATR FT IR spectra of various materials". [Online]. Available: http://lisa.chem.ut.ee/IR_spectra/paint/fillers/sand/. [12] B. Ribeiro da Luz, "Attenuated total reflectance spectroscopy of plant leaves: a tool for ecological and botanical studies", New P hytologist vol. 172, no. 2, pp. 305 318, 2006. Acknowledgements: Acknowledgements to this project include David Silvey who collected and supplied the samples, the Brennan Research Group and Gary Schei ffle for sample preparation Dr. Ruzycki for use of t he Phenom system, and the Andrew Research Group for use of the FTIR. I would like to thank Dr. Indarawis for leading me through this project and for being a wonderful men tor, always encouraging me to continually push forward Most importantly I would like to

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13 acknowledge Jesus Christ who created me to think and explore to give Him all the glory and honor Appendix SEM Images TAFB Samples

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14 UF Reclamation FTIR Peaks (cm 1 ) Cellulose 1627 1429 1373 1325 1162 1112 1062 1026 899 Hemi cellulose 1639 1465 1416 1328 1251 1215 1162 1075 1043 990 897 Tyndall 1629 1464 1434 1419 1377 1335/1318 1234 1158 1032 900 Table 1. Cell ulose and Hem icellulose FTIR peak comparison

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15 T able 2. Urea FTIR peak comparison Peaks (cm 1 ) Urea 3440 3320 3250 1685 1620 1608 1470 1155 1058 1000 Tyndall 3281 1629 1464 1158 1051 Figure 4 FTIR comparison to oil peaks Figure 3. FTIR comparison to urea peaks

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16 Peaks (cm 1 ) Extra Virgin Olive Oil 3005 2924/ 2852 1743 1465 1417 1402 1377 1236/ 1160 1117/ 1098 1030 962 850 721 Tyndall 2916/ 2849 1731 1464 1419 1377 1234/ 1158 1032 719 Figure 5. FTIR comparison to SiO2 T able 4. SiO2 peak comparison Peaks (cm 1 ) SiO 2 1162 1051 794 777 694 588 516 Tyndall 1158 1050 797 699 NA NA Table 3. Oil peak comparison

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17 Figure 6. FTIR comparison to papaya leaf Peaks (cm 1 ) Papaya Male Leaf 3392 2919 2851 1619 1421 1377 1317 1028 782 681 673 665 658 Papaya Male Flower 3276 2922 2853 1734 1605 1383 1318 1244 1024 780 Tyndall 3281 2916 2849 1731 1629 1419 1377 1318 1234 1032 797 699 67 4 666 653 Table 5. Papaya leaf peak comparison