Analysis of Polycyclic Aromatic Hydrocarbon Content in Ash from Solid Fuel Combustion in Low-Power Boilers
Abstract
:1. Introduction
2. Materials and Methods
- CWWA—PAH content;
- Am—measured peak area of the compound in the sample extract;
- f—total dilution factor of the extract;
- V—volume of the final extract;
- a—slope of the calibration graph with respect to the OX axis;
- b—the point of intersection of the calibration graph with the OY axis;
- m1—mass of flask and sewage sample;
- m2—the mass of the empty flask.
- ƩLMW (Low Molecular Weight), (2–4 rings in the compound structure: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene);
- ƩHMW (High Molecular Weight), (4–6 rings in the compound structure: fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(b)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, indeno(1,2,3,c,d)pyrene, benzo(g,h,i)perylene);
- ƩPAH the sum of 16 aromatic hydrocarbons.
3. Results
ANOVA One-Way Analysis of Variance
4. Discussion
5. Conclusions
- As a result of the content of ∑PAH in the fly ash, the fuels may be aligned in the following way: pellets of 6 mm grain size < hard coal of 25–80 mm grain size < hard coal of 60 mm grain size < hard coal of 25 mm grain size < mixed fire wood.
- It was also noticed that the content of the light fraction (LMM) in the fly ash of the researched fuels in ∑PAH was significantly greater than the content of soot, and it exceeded 57% in the case of the pellets of 6 mm, and in the ash from the firewood and coal of >60 mm, it was about 90%. The opposite dependence was noticed in the case of the hard fraction (HMW).
- It should be noted that a bigger percentage share of LMW in the sum of PAH proves the occurrence of easier biodegradable compounds. In order to confirm the presented hypothesis that the content of ∑PAH, ∑LMW, and ∑HMW in the samples of fly ash depends on the type of the combusted fuel, a one-factor variance analysis was conducted. It was assumed that the differences were understood as significant when the p value was lower than 0.05. In the one-factor variance analysis of the fly ash samples, the type of fuel was the qualitative classifying factor.
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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PAH | Retention Time [min] | Linear Calibration Equation | R2 |
---|---|---|---|
Naphthalene | 7.198 | y = 1,778,670.7x + 8025.24 | 0.9997 |
Acenaphthylene | 11.714 | y = 1,867,839.9x − 39,037.1 | 0.9992 |
Acenaphthene | 12.418 | y = 1,133,594.1x − 8518.3 | 0.9996 |
Fluorene | 14.446 | y = 1,370,497.2x − 36,419.2 | 0.9986 |
Phenanthrene | 18.641 | y = 1,764,785.4x − 80,684.4 | 0.9971 |
Anthracene | 18.846 | y = 1,482,715.9x − 12,641.6 | 0.9958 |
Fluoranthene | 24.365 | y = 1,444,292.6x − 28,284.7 | 0.9902 |
Pyrene | 25.391 | y = 1,109,499.1x − 12,585.1 | 0.9943 |
Benzo(a)anthracene | 31.431 | y = 368,067.3x − 4462.8 | 0.9883 |
Chrysene | 31.621 | y = 393,026.8x − 5212.7 | 0.9922 |
Benzo(b)fluoranthene | 36.502 | y = 181,984.1x + 8785.6 | 0.9991 |
Benzo(k)fluoranthene | 36.611 | y = 199,290.3x + 787.9 | 0.9997 |
Benzo(a) pyrene | 37.844 | y = 158,084.7x − 1847.5 | 0.9995 |
Indeno(1,2,3,c,d) pyrene | 42.544 | y = 169,634.8x + 24,040.5 | 0.9834 |
Dibenz(a,h) anthracene | 42.725 | y= 159,791.7x + 4015.6 | 0.9995 |
Benzo(g,h,i)perylene | 43.686 | y = 204,775.4x + 18,816.1 | 0.9926 |
Measurement Unit mg/kg DW | Mixed Firewood | Pellets of 6 mm | Hard Coal of 8–25 mm | Hard Coal of 25–80 mm | Hard Coal of >60 mm |
---|---|---|---|---|---|
Naphthalene | 2.391 + 0.181 | 0.049 ± 0.007 | 1.422 ± 0.341 | 0.155 ± 0.041 | 1.234 ± 0.281 |
Acenaphthylene | 1.021 ± 0.065 | 0.007 ± 0.001 | 0.447 ± 0.289 | 0.0176 ± 0.011 | 0.189 ± 0.108 |
Acenaphthene | 0.057 ± 0.008 | 0.009 ± 0.002 | 0.032 ± 0.012 | 0.006 ± 0.001 | 0.041 ± 0.011 |
Fluorene | 0.031 ± 0.011 | 0.002 ± 0.001 | 0.091 ± 0.31 | 0.004 ± 0.002 | 0.039 ± 0.16 |
Phenanthrene | 0.252 ± 0.063 | 0.004 ± 0.001 | 0.162 ± 0.111 | 0.005 ± 0.002 | 0.073 ± 0.061 |
Anthracene | 0.044 ± 0.007 | 0.002 ± 0.001 | 0.039 ± 0.019 | 0.002 ± 0.001 | 0.017 ± 0.009 |
Fluoranthene | 0.157 ± 0.026 | 0.003 ± 0.001 | 0.097 ± 0.067 | 0.003 ± 0.001 | 0.018 ± 0.011 |
Pyrene | 0.078 ± 0.028 | 0.004 ± 0.001 | 0.094 ± 0.046 | 0.002 ± 0.001 | 0.017 ± 0.011 |
Benzo(a)anthracene | 0.019 ± 0.002 | 0.004 ± 0.001 | 0.0302 ± 0.014 | 0.005 ± 0.001 | 0.006 ± 0.002 |
Chrysene | 0.031 ± 0.003 | 0.007 ± 0.001 | 0.042 ± 0.017 | 0.008 ± 0.001 | 0.009 ± 0.002 |
Benzo(b)fluoranthene | 0.035 ± 0.013 | 0.009 ± 0.002 | 0.023 ± 0.011 | 0.009 ± 0.003 | 0.014 ± 0.005 |
Benzo(k)fluoranthene | 0.029 ± 0.006 | 0.012 ± 0.003 | 0.0532 ± 0.041 | 0.012 ± 0.002 | 0.015 ± 0.003 |
Benzo(a)pyrene | 0.038 ± 0.007 | 0.002 ± 0.001 | 0.019 ± 0.011 | 0.002 ± 0.001 | 0.003 ± 0.001 |
Indeno(1,2,3,c,d)pyrene | 0.00 ± 0.000 | 0.00 ± 0.000 | 0.032 ± 0.006 | 0.00 ± 0.000 | 0.00 ± 0.000 |
Dibenz(a,h) anthracene | 0.008 ± 0.001 | 0.014 ± 0.009 | 0.244 ± 0.067 | 0.037 ± 0.003 | 0.083 ± 0.034 |
Benzo(g,h,i)perylene | 0.00 ± 0.000 | 0.00 ± 0.000 | 0.00 ± 0.000 | 0.00 ± 0.000 | 0.029 ± 0.009 |
ƩPAH | 4.191 ± 0.091 | 0.128 ± 0.004 | 2.827 ± 1.056 | 0.261 ± 0.064 | 1.782 ± 0.356 |
ƩLMW | 3.796 ± 0.149 | 0.073 ± 0.013 | 2.192 ± 0.765 | 0.182 ± 0.009 | 1.588 ± 0.587 |
ƩHMW | 0.395 ± 0.061 | 0.055 ± 0.017 | 0.635 ± 0.079 | 0.079 ± 0.013 | 0.194 ± 0.115 |
Sample Number | Tukey’s HSD Test for PAH Variable Approximate Probabilities for Post Hoc Tests Mean Squares Error: between-Group = 0.74066, Degrees of Freedom = 10 | |||||
---|---|---|---|---|---|---|
Fuel Type | {1} <4.1910> | {2} <0.1285> | {3} <1.7819> | {4} <0.2605> | {5} <2.8266> | |
1 | Mixed firewood | 0.001421 | 0.040509 | 0.001783 | 0.357110 | |
2 | Pellets of 6 mm | 0.001421 | 0.205744 | 0.999685 | 0.021472 | |
3 | Hard coal of >60 mm | 0.040509 | 0.205744 | 0.266916 | 0.592205 | |
4 | Hard coal of 25–80 mm | 0.001783 | 0.999685 | 0.266916 | 0.028678 | |
5 | Hard coal of 8–25 mm | 0.357110 | 0.021472 | 0.592205 | 0.028678 |
Sample Number | Tukey’s HSD Test for PAH Variable Homogeneous Groups, Alpha = 0.05 Mean Squares Error: Between-Group = 0.74066, Degrees of Freedom = 10 | ||||
---|---|---|---|---|---|
Fuel Type | ∑PAHaverage | ||||
2 | Pellets of 6 mm | 0.128546 | a | ||
4 | Hard coal of 25–80 mm | 0.260548 | a | ||
3 | Hard coal of >60 mm | 1.781930 | ab | ab | |
5 | Hard coal of 8–25 mm | 2.826564 | bc | bc | |
1 | Mixed firewood | 4.190980 | c |
Sample Number | Tukey’s HSD Test for PAH Variable Approximate Probabilities for Post Hoc Tests Mean Squares Error: between-Group = 0.74649, Degrees of Freedom = 10 | |||||
---|---|---|---|---|---|---|
Fuel Type | {1} <3.7957> | {2} <0.07313> | {3} <1.5879> | {4} <0.18176> | {5} <2.1919> | |
1 | Mixed firewood | 0.002208 | 0.056184 | 0.002721 | 0.210468 | |
2 | Pellets of 6 mm | 0.002208 | 0.252077 | 0.999840 | 0.068648 | |
3 | Hard coal of >60 mm | 0.056184 | 0.252077 | 0.311490 | 0.897945 | |
4 | Hard coal of 25–80 mm | 0.002721 | 0.999840 | 0.311490 | 0.087546 | |
5 | Hard coal of 8–25 mm | 0.210468 | 0.068648 | 0.897945 | 0.087546 |
Sample Number | Tukey’s HSD Test for LMW Variable Homogeneous Groups, Alpha = 0.05 Mean Squares Error: Between-Group = 0.74649, Degrees of Freedom = 10 | |||
---|---|---|---|---|
Fuel Type | LMWaverage | 1 | 2 | |
2 | Pellets of 6 mm | 0.073126 | a | |
4 | Hard coal of 25–80 mm | 0.181763 | a | |
3 | Hard coal of >60 mm | 1.587876 | ab | ab |
5 | Hard coal of 8–25 mm | 2.191884 | ab | ab |
1 | Mixed firewood | 3.795658 | b |
Sample Number | Tukey’s HSD Test for PAH Variable Approximate Probabilities for Post Hoc Tests Mean Squares Error: between-Group = 0.00841, Degrees of Freedom = 10 | |||||
---|---|---|---|---|---|---|
Fuel Type | {1} <0.39532> | {2} <0.05542> | {3} <0.19405> | {4} <0.07878> | {5} <0.63468> | |
1 | Mixed firewood | 0.007533 | 0.126215 | 0.011942 | 0.058036 | |
2 | Pellets of 6 mm | 0.007533 | 0.399028 | 0.997636 | 0.000260 | |
3 | Hard coal of >60 mm | 0.126215 | 0.399028 | 0.562722 | 0.001250 | |
4 | Hard coal of 25–80 mm | 0.011942 | 0.997636 | 0.562722 | 0.000304 | |
5 | Hard coal of 8–25 mm | 0.058036 | 0.000260 | 0.001250 | 0.000304 |
Sample Number | Tukey’s HSD Test for HMW Variable Homogeneous Groups, Alpha = 0.05 Mean Squares Error: between-Group = 0.00841, Degrees of Freedom = 10 | ||||
---|---|---|---|---|---|
Fuel Type | HMWaverage | 1 | 2 | 3 | |
2 | Pellets of 6 mm | 0.055419 | a | ||
4 | Hard coal of 25–80 mm | 0.078785 | a | ||
3 | Hard coal of >60 mm | 0.194054 | ab | ab | |
1 | Mixed firewood | 0.395323 | bc | bc | |
5 | Hard coal of 8–25 mm | 0.634679 | c |
Methods of Using Fly Ash | Literature |
---|---|
| [31] |
| [32] |
| [33] |
| [34] |
| [32] |
| [35] |
| [36,37] |
| [38] |
| [39] |
| [32] |
| [23] |
| [39] |
| [40,41] |
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Szatyłowicz, E.; Walendziuk, W. Analysis of Polycyclic Aromatic Hydrocarbon Content in Ash from Solid Fuel Combustion in Low-Power Boilers. Energies 2021, 14, 6801. https://doi.org/10.3390/en14206801
Szatyłowicz E, Walendziuk W. Analysis of Polycyclic Aromatic Hydrocarbon Content in Ash from Solid Fuel Combustion in Low-Power Boilers. Energies. 2021; 14(20):6801. https://doi.org/10.3390/en14206801
Chicago/Turabian StyleSzatyłowicz, Ewa, and Wojciech Walendziuk. 2021. "Analysis of Polycyclic Aromatic Hydrocarbon Content in Ash from Solid Fuel Combustion in Low-Power Boilers" Energies 14, no. 20: 6801. https://doi.org/10.3390/en14206801