Bioventing is conducted on one-dimensional soil columns. A numerical model is developed for simulating the mass exchange, adivective and dispersive transport and biodegradation of toluene. The model parameters are est...Bioventing is conducted on one-dimensional soil columns. A numerical model is developed for simulating the mass exchange, adivective and dispersive transport and biodegradation of toluene. The model parameters are estimated independently through laboratory batch experiments, or from literature. Simulations are found to provide reasonable agreement with experimental data. Experimental results show that toluene removal due to biodegradiation is more important at the later stage. The total cleanup time when NAPL (non-aqueous phase liquid) phase exists was twice more than that without NAPL. Sensitivity analysis of parameters suggests that model predictions are mainly dependent on mass transfer coefficient and microbial parameters, such as the half-saturation coefficient and maximum specific substrate utilization rate.展开更多
Normal alkane compounds dodecane, penta- decane, hexadecane, octadecane, tetracosane, isoprenoid alkane pristane and a crude oil sample were aerobically bio- degraded with a pure bacterial strain GIM2.5 and white rot ...Normal alkane compounds dodecane, penta- decane, hexadecane, octadecane, tetracosane, isoprenoid alkane pristane and a crude oil sample were aerobically bio- degraded with a pure bacterial strain GIM2.5 and white rot fungus Phanerochaete Chrysosporium-1767 to monitor the kinetic fractionation of the molecular stable carbon (δ C) 13 and hydrogen (δ D) isotopes in the course of biodegradation. Both δ C (V-PDB ) and δ D (V-SMOW) remained stable for 13 the standard alkane compounds and n-alkane components (from n-C13 to n-C25) of the crude oil, generally varying in the range of ±0.5‰ and ±5‰ respectively, within the range of the instrumental precisions, especially for those molecularly heavier than n-C16 during microbial degradation. These re- sults indicate that molecular stable carbon and hydrogen isotopic fingerprints can be promising indicators for tracing the sources of petroleum-related contaminants in the envi- ronment, especially in the case of severe weathering when they are difficult to be unambiguously identified by the chemical fingerprints alone.展开更多
基金the National Natural Science Foundation of China (No. 20276048).
文摘Bioventing is conducted on one-dimensional soil columns. A numerical model is developed for simulating the mass exchange, adivective and dispersive transport and biodegradation of toluene. The model parameters are estimated independently through laboratory batch experiments, or from literature. Simulations are found to provide reasonable agreement with experimental data. Experimental results show that toluene removal due to biodegradiation is more important at the later stage. The total cleanup time when NAPL (non-aqueous phase liquid) phase exists was twice more than that without NAPL. Sensitivity analysis of parameters suggests that model predictions are mainly dependent on mass transfer coefficient and microbial parameters, such as the half-saturation coefficient and maximum specific substrate utilization rate.
文摘Normal alkane compounds dodecane, penta- decane, hexadecane, octadecane, tetracosane, isoprenoid alkane pristane and a crude oil sample were aerobically bio- degraded with a pure bacterial strain GIM2.5 and white rot fungus Phanerochaete Chrysosporium-1767 to monitor the kinetic fractionation of the molecular stable carbon (δ C) 13 and hydrogen (δ D) isotopes in the course of biodegradation. Both δ C (V-PDB ) and δ D (V-SMOW) remained stable for 13 the standard alkane compounds and n-alkane components (from n-C13 to n-C25) of the crude oil, generally varying in the range of ±0.5‰ and ±5‰ respectively, within the range of the instrumental precisions, especially for those molecularly heavier than n-C16 during microbial degradation. These re- sults indicate that molecular stable carbon and hydrogen isotopic fingerprints can be promising indicators for tracing the sources of petroleum-related contaminants in the envi- ronment, especially in the case of severe weathering when they are difficult to be unambiguously identified by the chemical fingerprints alone.
