Primary Sludge from Dairy and Meat Processing Wastewater and Waste from Biomass Enzymatic Hydrolysis as Resources in Anaerobic Digestion and Co-Digestion Supplemented with Biodegradable Surfactants as Process Enhancers
Abstract
:1. Introduction
1.1. Meat and Dairy Wastewater Sludge
1.2. Biomass Waste after Enzymatic Hydrolysis
1.3. Fats, Oils and Grease Anaerobic Digestion
1.4. Surfactant Influence on the AD Process
2. Materials and Methods
2.1. Substrate and Inoculum Analyses
2.2. Biomethane Potential Determination
2.3. Statistical Analyses
3. Results and Discussion
3.1. Selected Substrate BMP and Organic Loading
3.2. Surface Active Substance Influence on Selected Substrate BMP
3.3. BHW and FOG-Containing Primary Sludge Co-Digestion with SAS Addition
3.4. BMP Outcome from Substrate Digestion and Co-Digestion and the Influence on Biomethane Release
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Parameter | Meat Production Wastewater | Dairy Wastewater | ||
---|---|---|---|---|
Beef | Poultry | Pork | ||
COD, mg/L | 4220 | 950 | 4310 | 2131 |
BOD, mg/L | 1209 | 400 | - | 1536 |
TN, mg/L | 427 | 80 | 275 | 273 |
TP | - | - | - | 60 |
TSS, mg/L | 1164 | 240 | 1240 | - |
FOG, g/L | 0.120 | 0.125 | 0.2–2.88 [13] |
Parameter | DWW DAF Primary Sludge | MPWW DAF Primary Sludge | ||
---|---|---|---|---|
Literature Value [19] | This Study * | Literature Value [16] | This Study * | |
Dry mater (DM)% of Wt. | 25.9 | 11.96 | 91.37 | 53.67 ± 0.81 |
OM (% of DM) | 46.9 | 9.52 | 69 | 53.63 ± 0.93 |
pH | 7.2 | 7.4 | 8.23 | 7.2 ± 0.1 |
TN (g/kg) | 19.5 | x | n/a | x |
TP (g/kg) | 65.9 | x | n/a | x |
TC (total carbon) (g/kg) | 24.3 | x | 45.58 (dry basis) | x |
Lipid content (wt% dry sludge) | x | x | 12.98 | x |
n-Hexane extractable substances (wt% of DM) | x | 14.21 | x | 82.32 ± 3.76 |
Sample ID | VS Total Loaded, (g/kg) | Inoculum VS, (gVS/kg) | GEHL, (gVS/kg) | DWW DAF Sludge, (gVS/kg) | MPWW DAF Sludge, (gVS/kg) | SAS, ppm | Substrate BMP, mLCH4/gVS |
---|---|---|---|---|---|---|---|
BHW 2.5% | 34.9 | 34 | 0.9 | X | X | X | 39.8 |
BHW 5% | 35.7 | 34 | 1.7 | X | X | X | 39.8 |
BHW 7% | 34.6 | 32.3 | 2.3 | X | X | X | 106.1 |
BHW 13% | 36.5 | 32.3 | 4.2 | X | X | X | 106.1 |
DWW DAF 10% | 34.0 | 32.4 | X | 1.6 | X | X | 94.8 |
DWW DAF 20% | 35.6 | 32.4 | X | 3.2 | X | X | 94.8 |
DWW DAF 30% | 37.3 | 32.4 | X | 4.9 | X | X | 94.8 |
DWW DAF 40% | 37.9 | 32.4 | X | 5.5 | X | X | 94.8 |
MPWW DAF 10% | 30.3 | 27.5 | X | X | 2.75 | X | 52.4 |
MPWW DAF 20% | 33.0 | 27.5 | X | X | 5.5 | X | 52.4 |
MPWW DAF 30% | 35.8 | 27.5 | X | X | 8.3 | X | 52.4 |
DWW DAF 10%/0.1% SAS | 33.4 | 30.3 | X | 3.03 | X | 100 | 80.5 |
DWW DAF 10%/0.2% SAS | 33.5 | 30.3 | X | 3.03 | X | 200 | 80.5 |
DWW DAF 10% | 33.3 | 30.3 | X | 3.03 | X | X | 80.5 |
MPWW DAF 10%/0.2% SAS | 44.8 | 40.6 | X | 4.1 | X | 100 | 61.5 |
MPWW DAF 10%/0.4% SAS | 44.9 | 40.6 | X | 4.1 | X | 200 | 61.5 |
MPWW DAF 10% | 44.7 | 40.6 | X | 4.1 | X | X | 61.5 |
DWW DAF 10%/BHW 2.5%/SAS 0.2% | 33.1 | 29.3 | 0.7 | 2.9 | X | 200 | 106.3 |
DWW DAF 10%/BHW 5%/SAS 0.2% | 33.9 | 29.3 | 1.5 | 2.9 | X | 200 | 106.3 |
MPWW DAF 10%/BHW 2.5%/SAS 0.2% | 38.5 | 34.0 | 0.9 | X | 3.4 | 200 | 39.8 |
MPWW DAF 10%/BHW 5.0%/SAS 0.2% | 39.3 | 34.0 | 1.7 | X | 3.4 | 200 | 39.8 |
Sample ID | Inoculum BMP, mLCH4/gVS | Sample BMP, mLCH4/gVS | 75% BMP Output, Days |
---|---|---|---|
BHW 13% | 39.8 ± 1.8 | 473.2 ± 5.8 | 15 |
BHW 7% | 39.8 ± 1.8 | 210.2 ± 25.1 | 10 |
BHW 5% | 106.1 ± 5.3 | 549.7 ± 25.1 | 8 |
BHW 2.5% | 106.1 ± 2.3 | 549 ± 42.7 | 4 |
DWW DAF 40% | 94.8 ± 4.8 | 510.0 ± 30.2 | 19 |
DWW DAF 30% | 94.8 ± 4.8 | 593.1 ± 48.5 | 18 |
DWW DAF 20% | 94.8 ± 4.8 | 597.4 ± 19.2 | 15 |
DWW DAF 10% | 94.8 ± 4.8 | 690.7 ± 54.8 | 14 |
MPWW DAF 30% | 52.4 ± 5.3 | 834.7 ± 25.8 | 28 |
MPWW DAF 20% | 52.4 ± 5.3 | 1077.1 ± 45.0 | 18 |
MPWW DAF 10% | 52.4 ± 5.3 | 979.9 ± 37.3 | 10 |
DWW DAF 10% VS 0.1% SAS | 80.5 ± 3.4 | 607.2 ± 12.4 | 21 |
DWW DAF 10% VS 0.2% SAS | 80.5 ± 3.4 | 629.4 ± 10.2 | 21 |
DWW DAF 10% | 80.5 ± 3.4 | 440.8 ± 61.7 | 19 |
MPWW DAF 10% VS + SAS 0.1% | 61.5 ± 2.1 | 1531.1 ± 50.2 | 12 |
MPWW DAF 10% VS + SAS 0.2% | 61.5 ± 2.1 | 1764.9 ± 55.4 | 14 |
MPWW DAF 10% | 61.5 ± 2.1 | 1374.5 ± 47.6 | 15 |
DWW DAF 10%/BHW 2.5%/SAS 0.2% | 106.3 ± 4.2 | 534.3 ± 25.8 | 15 |
DWW DAF 10%/BHW 5.0%/SAS 0.2% | 106.3 ± 4.2 | 470.7 ± 6.2 | 16 |
MPWW DAF 10%/BHW 2.5%/SAS 0.2% | 39.8 ± 1.8 | 739.5 ± 22.8 | 10 |
MPWW DAF 10%/BHW 5.0%/SAS 0.2% | 39.8 ± 1.8 | 574.3 ± 50.2 | 9 |
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Skripsts, E.; Mezule, L.; Klaucans, E. Primary Sludge from Dairy and Meat Processing Wastewater and Waste from Biomass Enzymatic Hydrolysis as Resources in Anaerobic Digestion and Co-Digestion Supplemented with Biodegradable Surfactants as Process Enhancers. Energies 2022, 15, 4333. https://doi.org/10.3390/en15124333
Skripsts E, Mezule L, Klaucans E. Primary Sludge from Dairy and Meat Processing Wastewater and Waste from Biomass Enzymatic Hydrolysis as Resources in Anaerobic Digestion and Co-Digestion Supplemented with Biodegradable Surfactants as Process Enhancers. Energies. 2022; 15(12):4333. https://doi.org/10.3390/en15124333
Chicago/Turabian StyleSkripsts, Eriks, Linda Mezule, and Elvis Klaucans. 2022. "Primary Sludge from Dairy and Meat Processing Wastewater and Waste from Biomass Enzymatic Hydrolysis as Resources in Anaerobic Digestion and Co-Digestion Supplemented with Biodegradable Surfactants as Process Enhancers" Energies 15, no. 12: 4333. https://doi.org/10.3390/en15124333