Inverse modeling of BTEX dissolution and biodegradation at the Bemidji, MN crude-oil spill site
Inverse modeling of BTEX dissolution and biodegradation at the Bemidji, MN crude-oil spill site
复制标题
DOI：
10.1016/s0169-7722(03)00034-2
复制
发表时间：
2003-12-01
影响因子：
3.6
通讯作者：
Delin, GN
中科院分区：
文献类型：
--
作者：
Essaid, HI;Cozzarelli, IM;Delin, GN
美国地质调查局（USGS）溶质运移和生物降解代码BIOMOC与USGS通用逆向建模代码UCODE结合使用，以量化位于明尼苏达州贝米吉附近的USGS有毒物质水文计划原油泄漏研究现场的现场规模碳氢化合物溶解和生物降解。这一逆向建模工作使用了1986年至1997年在贝米吉现场汇编的大量历史数据，并纳入了多组分迁移和生物降解模型。当耦合的传输和降解过程被纳入模型和一个单一的溶解速率系数被用于所有BTEX组件的逆建模是成功的。假设一个固定的油体，我们模拟苯，甲苯，二甲苯，间，对二甲苯，邻二甲苯（BTEX）的浓度分别在石油和地下水，以及溶解氧。从油相溶解和好氧和厌氧降解过程中的代表。参数估计的补给率，水力传导率，溶解速率系数，个人一阶BTEX厌氧降解率，横向分散性。使用水文系统和生物降解过程的几种替代概念模型获得的模拟结果相似。溶解的BTEX浓度数据不足以区分这些概念模型。经过校准的模拟再现了羽流的一般大规模演变，但没有再现所观察到的小规模浓度的空间和时间变化。估算的甲苯和邻二甲苯的厌氧生物降解速率大于溶解速率系数。然而，估计的厌氧生物降解速率苯，间二甲苯，间，对二甲苯小于溶解速率系数。校正后的模型用于确定油体和地下水羽流中的BTEX质量平衡。从油体的溶解是最大的化合物具有大的有效溶解度（苯）和大的降解率（甲苯和邻二甲苯）。厌氧降解去除了77%的溶于水相的BTEX，好氧降解去除了17%。虽然替代概念模型的拟合优度指标没有显着差异，但模型的预测差异很大。(C)2003 Elsevier Science B.V.保留所有权利。
The U.S. Geological Survey (USGS) solute transport and biodegradation code BIOMOC was used in conjunction with the USGS universal inverse modeling code UCODE to quantify field-scale hydrocarbon dissolution and biodegradation at the USGS Toxic Substances Hydrology Program crude-oil spill research site located near Bemidji, MN. This inverse modeling effort used the extensive historical data compiled at the Bemidji site from 1986 to 1997 and incorporated a multicomponent transport and biodegradation model. Inverse modeling was successful when coupled transport and degradation processes were incorporated into the model and a single dissolution rate coefficient was used for all BTEX components. Assuming a stationary oil body, we simulated benzene, toluene, ethylbenzene, m,p-xylene, and o-xylene (BTEX) concentrations in the oil and ground water, respectively, as well as dissolved oxygen. Dissolution from the oil phase and aerobic and anaerobic degradation processes were represented. The parameters estimated were the recharge rate, hydraulic conductivity, dissolution rate coefficient, individual first-order BTEX anaerobic degradation rates, and transverse dispersivity. Results were similar for simulations obtained using several alternative conceptual models of the hydrologic system and biodegradation processes. The dissolved BTEX concentration data were not sufficient to discriminate between these conceptual models. The calibrated simulations reproduced the general large-scale evolution of the plume, but did not reproduce the observed small-scale spatial and temporal variability in concentrations. The estimated anaerobic biodegradation rates for toluene and o-xylene were greater than the dissolution rate coefficient. However, the estimated anaerobic biodegradation rates for benzene, ethylbenzene, and m,p-xylene were less than the dissolution rate coefficient. The calibrated model was used to determine the BTEX mass balance in the oil body and groundwater plume. Dissolution from the oil body was greatest for compounds with large effective solubilities (benzene) and with large degradation rates (toluene and o-xylene). Anaerobic degradation removed 77% of the BTEX that dissolved into the water phase and aerobic degradation removed 17%. Although goodness-of-fit measures for the alternative conceptual models were not significantly different, predictions made with the models were quite variable. (C) 2003 Elsevier Science B.V. All rights reserved.