Coagulation of Chitin Production Wastewater from Shrimp Scraps with By-Product Chitosan and Chemical Coagulants
Abstract
:1. Introduction
2. Materials and Methods
2.1. Sample of Wastewater
2.2. Reagents and Apparatus
2.3. Analytical Methods
2.4. Experimental Design
2.4.1. Preliminary Sedimentation Experiments
2.4.2. Coagulation and Flocculation Experiments by Chitosan, PAC, and PAA
2.5. Response Surface Designs and Analysis
3. Results and Discussion
3.1. Preliminary Sedimentation Efficiency
3.2. Coagulation by Chitosan (Experiment 1)
3.3. Coagulation by PAC (Experiment 2)
3.4. Coagulation by PAA (Experiment 3)
3.5. Coagulation and Flocculation by PAC and PAA (Experiment 4)
3.6. Comparison between Studied Coagulants
3.7. Optimal Conditions of Chitosan Coagulation
3.7.1. Traditional Experimental Design
3.7.2. Box-Wilson Central Composite Design (Experiment 5)
3.7.3. Comparison of Treatment Performances between Two Optimal Points from Traditional Design and Central Composite Design
3.8. Correlation between Crude Protein and Calcium Ratio with Turbidity Removal Performances
4. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Parameters | Values |
---|---|
PH | 3.55–7.41 |
COD (mg·L−1) | 4245–23,600 |
TKN (mg·L−1) | 639–1395 |
NH4+–N (mg·L−1) | 145–842 |
TP (mg·L−1) | 53–366 |
TSS (mg·L−1) | 1880–10,400 |
Ca2+ (mg·L−1) | 1200–3163 |
Crude protein (mg·L−1) | 3994–8719 |
Turbidity (NTU) | 363–1254 |
No | Experiment 1 (Chitosan) | Experiment 2 (PAC) | Experiment 3 (PAA) | Experiment 4 (PAC and PAA) | Experiment 5 (optimization) | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Initial turbidity: 523 NTU Turbidity after settling: 79 NTU | Initial turbidity: 493 NTU Turbidity after settling: 81 NTU | Initial turbidity: 511 NTU Turbidity after settling: 97 NTU | Initial turbidity: 511 NTU Turbidity after settling: 100 NTU | Initial turbidity: 963 NTU Turbidity after settling: 184 NTU | |||||||||||||||||
pH/Chitosan (mg·L−1)/Turbidity (NTU) | TRE * (%) | pH/PAC (mg·L−1)/Turbidity (NTU) | TRE * (%) | pH/PAA (mg·L−1)/Turbidity (NTU) | TRE * (%) | pH/PAC (mg·L−1)/PAA (mg·L−1)/Turbidity (NTU) | TRE * (%) | pH/Chitosan (mg·L−1)/Turbidity (NTU) | TRE * (%) | ||||||||||||
1 | 10.0 | 140.0 | 6 | 92.4 | 10.0 | 90.0 | 10 | 87.7 | 10.0 | 140.0 | 13 | 86.6 | 10.0 | 90.0 | 60.0 | 8 | 92.0 | 5.0 | 50.0 | 148 | 19.6 |
2 | 4.0 | 140.0 | 67 | 15.2 | 4.0 | 90.0 | 29 | 64.2 | 4.0 | 140.0 | 92 | 5.2 | 4.0 | 90.0 | 60.0 | 37 | 63.0 | 9.0 | 50.0 | 23 | 87.5 |
3 | 10.0 | 40.0 | 12 | 84.8 | 10.0 | 30.0 | 9 | 88.9 | 10.0 | 40.0 | 8 | 91.8 | 10.0 | 30.0 | 60.0 | 8 | 92.0 | 5.0 | 100.0 | 150 | 18.5 |
4 | 4.0 | 40.0 | 70 | 11.4 | 4.0 | 30.0 | 40 | 50.6 | 4.0 | 40.0 | 86 | 11.3 | 4.0 | 30.0 | 60.0 | 49 | 51.0 | 9.0 | 100.0 | 20 | 89.1 |
5 | 11.2 | 90.0 | 8 | 89.9 | 11.2 | 60.0 | 5 | 93.8 | 11.2 | 90.0 | 2 | 97.9 | 10.0 | 90.0 | 20.0 | 6 | 94.0 | 9.8 | 75.0 | 19 | 89.7 |
6 | 2.8 | 90.0 | 58 | 26.6 | 2.8 | 60.0 | 43 | 46.9 | 2.8 | 90.0 | 87 | 10.3 | 4.0 | 90.0 | 20.0 | 32 | 68.0 | 4.2 | 75.0 | 153 | 16.8 |
7 | 7.0 | 160.7 | 49 | 38.0 | 7.0 | 102.4 | 13 | 84.0 | 7.0 | 160.7 | 18 | 81.4 | 10.0 | 30.0 | 20.0 | 6 | 94.0 | 7.0 | 110.4 | 12 | 93.48 |
8 | 7.0 | 19.3 | 27 | 65.8 | 7.0 | 17.6 | 16 | 80.2 | 7.0 | 19.3 | 14 | 85.6 | 4.0 | 30.0 | 20.0 | 44 | 56.0 | 7.0 | 39.7 | 13 | 92.93 |
9 | 7.0 | 90.0 | 12 | 84.8 | 7.0 | 60.0 | 13 | 84.0 | 7.0 | 90.0 | 15 | 84.5 | 11.1 | 60.0 | 40.0 | 2 | 98.0 | 7.0 | 75.0 | 21 | 88.6 |
10 | 7.0 | 90.0 | 13 | 83.5 | 7.0 | 60.0 | 13 | 84.0 | 7.0 | 90.0 | 18 | 81.4 | 3.0 | 60.0 | 40.0 | 38 | 62.0 | 7.0 | 75.0 | 19 | 89.7 |
11 | 7.0 | 90.0 | 19 | 75.9 | 7.0 | 60.0 | 17 | 79.0 | 7.0 | 90.0 | 17 | 82.5 | 7.0 | 100.6 | 40.0 | 13 | 87.0 | 7.0 | 75.0 | 18 | 90.2 |
12 | 7.0 | 19.4 | 40.0 | 13 | 87.0 | ||||||||||||||||
13 | 7.0 | 60.0 | 67.1 | 13 | 87.0 | ||||||||||||||||
14 | 7.0 | 60.0 | 12.9 | 13 | 87.0 | ||||||||||||||||
15 | 7.0 | 60.0 | 40.0 | 14 | 86.0 | ||||||||||||||||
16 | 7.0 | 60.0 | 40.0 | 13 | 87.0 | ||||||||||||||||
17 | 7.0 | 60.0 | 40.0 | 13 | 87.0 | ||||||||||||||||
18 | 10.6 | 86.4 | - | 99.4 | 11.2 | 17.6 | - | 93.5 | 9.8 | 79.3 | - | 99.5 | 11.0 | 48.1 | 39.2 | - | 98.9 | 8.3 | 77.5 | - | 99.3 |
Coagulants | Samples | pH | tCOD (mg·L−1) | sCOD (mg·L−1) | TKN (mg·L−1) | NH4+-N (mg·L−1) | TP (mg·L−1) | TSS (mg·L−1) | Ca2+ (mg·L−1) | Crude Protein (mg·L−1) |
---|---|---|---|---|---|---|---|---|---|---|
Preliminary sedimentation | Inlet wastewater | 5.6 | 4245 | 1621 | 639 | 145 | 53 | 1880 | 1200 | 3996 |
After settling | 4.0 | 2612 | 1584 | 579 | 133 | 40 | 139 | 1233 | 3617 | |
* RE (%) | 38 | 2 | 9 | 8 | 25 | 93 | −3 | 9 | ||
Chitosan 86.4 mg·L−1 | After coagulation | 10.6 | 1741 | 1463 | 453 | 103 | 5.2 | 39 | 587 | 2829 |
** REC (%) | 33 | 8 | 22 | 23 | 87 | 72 | 52 | 22 | ||
*** ToRE (%) | 59 | 10 | 29 | 29 | 90 | 98 | 51 | 29 | ||
PAC 17.6 mg·L−1 | After coagulation | 11.2 | 2116 | 1403 | 448 | 95 | 4.9 | 51 | 673 | 2800 |
** REC (%) | 19 | 11 | 23 | 29 | 88 | 63 | 45 | 23 | ||
*** ToRE (%) | 50 | 13 | 30 | 34 | 91 | 97 | 44 | 30 | ||
PAA 79.3 mg·L−1 | After coagulation | 9.8 | 2298 | 1246 | 520 | 146 | 4.2 | 38 | 587 | 3252 |
** REC (%) | 12 | 21 | 10 | −10 | 90 | 73 | 52 | 10 | ||
*** ToRE (%) | 46 | 23 | 19 | −1 | 92 | 98 | 51 | 19 | ||
Mixture of PAC and PAA 87.3 mg·L−1 | After coagulation | 11.0 | 1875 | 1645 | 462 | 98 | 4.3 | 44 | 660 | 2888 |
** REC (%) | 28 | −4 | 20 | 26 | 89 | 68 | 46 | 20 | ||
*** ToRE (%) | 56 | −1 | 28 | 32 | 92 | 98 | 45 | 28 |
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Tran, N.V.N.; Yu, Q.J.; Nguyen, T.P.; Wang, S.-L. Coagulation of Chitin Production Wastewater from Shrimp Scraps with By-Product Chitosan and Chemical Coagulants. Polymers 2020, 12, 607. https://doi.org/10.3390/polym12030607
Tran NVN, Yu QJ, Nguyen TP, Wang S-L. Coagulation of Chitin Production Wastewater from Shrimp Scraps with By-Product Chitosan and Chemical Coagulants. Polymers. 2020; 12(3):607. https://doi.org/10.3390/polym12030607
Chicago/Turabian StyleTran, Nguyen Van Nhi, Qiming Jimmy Yu, Tan Phong Nguyen, and San-Lang Wang. 2020. "Coagulation of Chitin Production Wastewater from Shrimp Scraps with By-Product Chitosan and Chemical Coagulants" Polymers 12, no. 3: 607. https://doi.org/10.3390/polym12030607
APA StyleTran, N. V. N., Yu, Q. J., Nguyen, T. P., & Wang, S.-L. (2020). Coagulation of Chitin Production Wastewater from Shrimp Scraps with By-Product Chitosan and Chemical Coagulants. Polymers, 12(3), 607. https://doi.org/10.3390/polym12030607