Print version CEE 697z Organic Compounds in Water and Wastewater Origins of NOM II Lecture #5 Dave Reckhow - Organics In W & WW
Carbohydrates • empirical formula: C x (H 2 O) y CH 2 OH CH 2 OH CH 2 OH H OH H H O O O H H O OH H OH H H OH H OH OH OH OH H OH H OH H OH Glucose (monosaccharide) Cellulose (polysaccharide) CH 2 OH H OH O Glucosamine (amino sugar) H OH H OH H H NH 2 2
Carbohydrates, cont. Nomenclature Monosaccharide: 1 simple sugar 1% of DOC Oligosaccharide: ≤ 10 simple sugars Polysaccharide: > 10 simple sugars 5% of DOC Special interest in distribution systems Food for microbial regrowth Major constituents of: soluble metabolic byproducts biofilms
Carbohydrates, cont. Function in plants Structural – cell walls Cellulose (~10,000 ᴅ -glucose units) Most abundant natural organic compound Mostly in higher plants; some algae have none Hemicelluloses (50-2000 monosaccharides of many types) Forms a matrix around cellulose fibers in cell walls Chitin (N-acetyl- ᴅ -glucosamine units) Second most abundant natural organic (~tied with lignin) Role of cellulose in most fungi, some algae & arthropods Murein or “peptidoglycan”, a major group of Acylheteropolysaccharides N-acetyl- ᴅ -glucosamine & N-acetylmuiramic acid cross linked by AA chains Dominant in Eubacteria: up to 75% of bacterial dry mass Energy – polysaccharides Starch in plants (80% amylopectin, 20% amylose) Anti-dessicants 4
Carbohydrates, cont. Algae etc., Heteropolysaccharides Nitrogen-containing 5
Carbohydrates, cont. 6
Acylheteropolysaccharides (APS) 10-35% of river and lake water DOC Produced by algae in fresh and salt waters Similar to structural polysaccharides? Comprised of a nearly fixed ratio of simple sugars, acetate and lipids Refractory like humic substances 7
Sugars in Natural Waters From: Perdue & Ritchie, 2004 8
At neutral pH’s most lose H + Fatty Acids CH 3 -COO - • maybe 4% of DOC • other mixed acids may account for 2% H-COOH CH 3 -COOH CH 3 -CH 2 -COOH Formic Acid Acetic Acid Propionic Acid CH 3 -CH 2 -CH 2 -COOH H 3 -CH 2 -CH 2 -CH 2 -COOH Butyric Acid Valeric Acid Common Volatile Fatty Acids in Natural Waters 9
Amino Acids and Proteins NH 2 Alanine Simple Amino Acids some may form THMs and H 2 C C COOH HANs H Proteins NH 2 much larger, comprised of HO C C COOH many AAs H 2 H Tyrosine Special interests in DWT – nutrients for bacterial regrowth 10 – role in chlorine decay and DBP formation
Amino Acids From: Perdue & Ritchie, 2004 11
Terpenes and Terpenoids The terpenoids , sometimes called isoprenoids , are a large and diverse class of naturally occurring organics similar to terpenes, derived from five- carbon isoprene units assembled and modified in thousands of ways. T erpenoids can be thought of as modified terpenes, wherein methyl groups have been moved or removed, or oxygen atoms added. Plant terpenoids are used extensively for their aromatic qualities. They play a role in traditional herbal remedies and are under investigation for antibacterial, antineoplastic, and other pharmaceutical functions. T erpenoids contribute to the scent of eucalyptus, the flavors of cinnamon, cloves, and ginger, the yellow color in sunflowers, and the red color in tomatoes. T erpenoids can be classified according to the number of isoprene units used: Hemiterpenoids, 1 isoprene unit (5 carbons) Monoterpenoids, 2 isoprene units (10C) Sesquiterpenoids, 3 isoprene units (15C) Diterpenoids, 4 isoprene units (20C) (e.g. ginkgolides) Sesterterpenoids, 5 isoprene units (25C) Triterpenoids, 6 isoprene units (30C) (e.g. sterols) T etraterpenoids, 8 isoprene units (40C) (e.g. carotenoids) Polyterpenoid with a larger number of isoprene units From Wikipedia 12
Terpenoids 13
Terpenoids, cont. 14
Iron Complexation 15
Van Krevlin Plot 16
Putting it all together? Hydroxy Acid OH COOH From Thurman, 1985 HO COOH COOH Aliphatic HOOC Dicarboxylic Phenolic-OH Acid O OH HOOC HO Aromatic Aliphatic Acid Dicarboxylic Acid H 3 CO COOH COOH Many identifiable precursor structures Aromatic 17 Not practical or even possible Acid
Concentrations: Pedogenic Land Sources From Woody & non-woody plants, lignin, etc. Depends on vegetation, soil, hydrology Attenuated by adsorption to clay soils Parallel watersheds in Australia (Cotsaris et al., 1994 [Chamonix proceedings]) Clearwater Creek, high clay content: 2.5 mg/L TOC Redwater Creek, sandy soil: 31.7 mg/L TOC 18
Concentrations: Aquagenic Algal & aquatic plant Sources Depend on nutrient levels / trophic state Concentrations in Lakes (mg/L) (Thurman, 1985) Trophic State Mean DOC Range Oligotrophic 2 1-3 Mesotrophic 3 2-4 Groundwater average: 0.7 mg/L Eutrophic 10 3-34 No algae, much soil attenuation Dystrophic 30 20-50 19
MW vs type Algogenic organic matter (AOM) Proteins & carbohydrates Large polymers with monomers Henderson et al., 2008 20
Algae as THM Precursors From: Plummer & Edzwald, 2001 [ES&T:35:3661] Scenedesmus quadricauda ~25% from EOM Cyclotella sp. Algae 21 pH 7, 20-24ºC, chlorine excess
Algae as TCAA Precursors Not much impact? Algae 22 pH 7, 20-24ºC, chlorine excess
Algae as DCAA Precursors Are Algae important sources of dihalo-AA precursors? Algae 23 pH 7, 20-24ºC, chlorine excess
Annual TOC Cycles 18 Hanahan WTP Edisto River TOC: Kornegay 16 Charleston, SC SUVA: ICR Former source 14 TOC: ICR TOC (mg/L) or SUVA (m -1 ) for Charleston’s 12 (SC) Hanahan Period 10 WTP of High 8 Runoff Flushing of TOC 6 during high 4 rainfall months 2 Influent Water (cold period) 0 0 2 4 6 8 10 12 14 16 18 20 ICR Month 6/1/1997 7/1/1997 8/1/1997 9/1/1997 10/1/1997 11/1/1997 12/1/1997 1/1/1998 2/1/1998 3/1/1998 4/1/1998 5/1/1998 6/1/1998 7/1/1998 8/1/1998 9/1/1998 10/1/1998 11/1/1998 12/1/1998 1/1/1999 2/1/1999 24 Approximate Date
Annual TOC Cycles High photosynthetic 4.0 activity TOC: Kornegay data SUVA: ICR Lake Lanier 3.5 TOC: ICR TOC (mg/L) or SUVA (m -1 ) 3.0 Source for Gwinnett Co.’s 2.5 (GA) Lanier 2.0 WTP 1.5 High clay content 1.0 in watershed Lake Lanier WTP 0.5 Gwinnet Co., GA Influent Water 0.0 0 2 4 6 8 10 12 14 16 18 20 ICR Month 6/1/1997 7/1/1997 8/1/1997 9/1/1997 10/1/1997 11/1/1997 12/1/1997 1/1/1998 2/1/1998 3/1/1998 4/1/1998 5/1/1998 6/1/1998 7/1/1998 8/1/1998 9/1/1998 10/1/1998 11/1/1998 12/1/1998 1/1/1999 2/1/1999 25 Approximate Date
0.10 6 0.09 DOC 5 0.08 0.07 -1 ) 4 DOC (mg/L) UV 285 (cm 0.06 0.05 3 UV 0.04 2 0.03 0.02 1 Spatial and Temporal 0.01 0.00 0 Distribution of DOC 50 100 150 200 250 300 350 Day of Year and UV absorbing Substances in Lake UV 285 (cm -1 ) UV 285 (cm -1 ) Bret 0.00 0.02 0.04 0.06 0.08 0.00 0.02 0.04 0.06 0.08 0 0 (from Zumstein UV 2 DOC 2 UV DOC & Buffle, 1989; 4 4 6 6 and Krasner et Depth (m) Depth (m) 8 8 10 10 al., 1996) 12 12 14 14 16 16 18 18 20 20 0 1 2 3 4 5 26 0 1 2 3 4 5 DOC (mg/L) DOC (mg/L)
THM Precursor Study Cannonsville Reservoir Epilimnion Catskill- Delaware water Hypolimnion supply for NYC Stepczuk et al., 1998 J. Lake Res. Mgmt. Both Epilimnion 14(2-3)356 27
Plant biochemicals Low Sugars, starches Moderate Proteins Low Cellulose Low Hemicellulose Low Fats & waxes high Lignins & phenolics Decreasing biodegradability Terpenoids - ?? Simplification: Doesn’t explicitly consider bacterial metabolites 28
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Dihalo and Trihalo DBPs Humic Acid Fulvic Acid NOM Fractions Weak Hydrophobic Acids Hydrophobic Bases Hydrophobic Neutrals Evidence for 1.4 Hydrophilic Acids Raw Waters Ultra Hydrophilic Acids greater Hydrophilic Bases CX 2 /CX 3 Formation Potential ( µ M/ µΜ) 1.2 Hydrophilic Neutrals importance of regression dihalo species in 1.0 non-lignin based 0.8 b[0]=0.4813029679 NOM b[1]=-0.0290898677 r ²=0.1466315169 0.6 0.4 0.2 0.0 0 1 2 3 4 5 6 7 8 9 10 30 Specific UV absorbance @ 254 nm (L/m/mg-C)
DHAN/THM Ratio vs SUVA 2.1 Humic Acid 2.0 All Samples Fulvic Acid 1.9 DHAN/THM Formation Potential ( µ g/ µ g) 1.8 Weak Hydrophobic Acids 1.7 Hydrophobic Bases 1.6 Hydrophobic Neutrals 1.5 Hydrophilic Acids 0.4 Ultra Hydrophilic Acids Hydrophilic Bases Hydrophilic Neutrals 0.3 regression b[0]=0.20 0.2 b[1]=-0.0177 r ²=9.2e-3 0.1 0.0 0 1 2 3 4 5 6 7 8 9 10 11 31 Specific UV absorbance @ 254 nm (L/m/mg-C)
DOC and runoff Ogeechee River (GA) From Aiken & Cotsaris, 1995 [JAWWA 87(1)36] 32
What is EfOM? Drinking NOM, NOM, water Wastewater DBPs NOM Water treatment Municipal DBPs source treatment plant use plant EfOM: NOM, DBPs Ambient water (river) Wastewater SMPs reclamation and reuse EfOM ≈ NOM + SMPs 33 from : Krasner & Am y
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