Simulation and optimization technologies for petroleum waste management and remediation process control

Leakage and spill of petroleum hydrocarbons from underground storage tanks and pipelines have posed significant threats to groundwater resources across many petroleum-contaminated sites. Remediation of these sites is essential for protecting the soil and groundwater resources and reducing risks to local communities. Although many efforts have been made, effective design and management of various remediation systems are still challenging to practitioners. In recent years, the subsurface simulation model has been combined with techniques of optimization to address important problems of contaminated site management. The combined simulation-optimization system accounts for the complex behavior of the subsurface system and identifies the best management strategy under consideration of the management objectives and constraints. During the past decades, a large number of studies were conducted to simulate contaminant flow and transport in the subsurface and seek cost-effective remediation designs. This paper gives a comprehensive review on recent developments, advancements, challenges, and barriers associated with simulation and optimization techniques in supporting process control of petroleum waste management and site remediation. A number of related methodologies and applications were examined. Perspectives of effective site management were investigated, demonstrating many demanding areas for enhanced research efforts, which include issues of data availability and reliability, concerns in uncertainty, necessity of post-modeling analysis, and usefulness of development of process control techniques.     

Diffusive partitioning tracer test for the quantification of nonaqueous phase liquid (NAPL) in the vadose zone: Performance evaluation for heterogeneous NAPL distribution

A partitioning tracer test based on gas-phase diffusion in the vadose zone yields estimates of the residual nonaqueous phase liquid (NAPL) saturation. The present paper investigates this technique further by studying diffusive tracer breakthrough curves in the vadose zone for a heterogeneous NAPL distribution. Tracer experiments were performed in a lysimeter with a horizontal layer of artificial kerosene embedded in unsaturated sand. Tracer disappearance curves at the injection point and tracer breakthrough curves at some distance from the injection point were measured inside and outside of the NAPL layer. A numerical code was used to generate independent model predictions based on the physicochemical sand, NAPL, and tracer properties. The measured and modeled tracer breakthrough curves were in good agreement confirming the validity of important modeling assumptions such as negligible sorption of chlorofluorocarbon (CFC) tracers to the uncontaminated sand and their fast reversible partitioning between the soil air and the NAPL phase. Subsequently, the model was used to investigate different configurations of NAPL contamination. The experimental and model results show that the tracer disappearance curves of a single-well diffusive partitioning tracer test (DPTT) are dominated by the near-field presence of NAPL around the tip of the soil gas probe. In contrast, breakthrough curves of inter-well tracer tests reflect the NAPL saturation in between the probes, although there is no unique interpretation of the tracer signals if the NAPL distribution is heterogeneous. Numerical modeling is useful for the planning of a DPTT application. Simulations suggest that several cubic meters of soil can be investigated with a single inter-well partitioning tracer test of 24-hour duration by placing the injection point in the center of the investigated soil volume and probes at up to 1 m distance for the monitoring of gaseous tracers.     

河南省区域性中心城市技术创新水平评价

在建立河南省区域中心城市技术创新测度指标体系的基础上,运用因子分析法,以河南省18个省辖(管)市为对象,对区域中心城市技术创新水平进行了测度,并将其划分为3种梯度类型。同时,分析了区域中心城市技术创新水平的地域差异,提出了河南省区域中心城市技术创新的基本构想。     

Combination of rhamnolipid and biochar in assisting phytoremediation of petroleum hydrocarbon contaminated soil using Spartina anglica

Biochar(BC) and rhamnolipid(RL) is used in bioremediation of petroleum hydrocarbons,however, the combined effect of BC and RL in phytoremediation has not been studied until now. In this paper, the phytoremediation of petroleum hydrocarbon-contaminated soil using novel plant Spartina anglica was enhanced by the combination of biochar(BC) and rhamnolipid(RL). Samples of petroleum-contaminated soil(10, 30 and 50 g/kg) were amended by BC, BC+ RL and rhamnolipid modified biochar(RMB), respectively. After 60 day's cultivation, the removal rate of total petroleum hydrocarbons(TPHs) for unplanted soil(UP), planted soil(P), planted soil with BC addition(P-BC), planted soil with BC and RL addition(P-BC + RL) and planted soil with addition of RMB(P-RMB) were 8.6%, 19.1%, 27.7%,32.4% and 35.1% in soil with TPHs concentration of 30 g/kg, respectively. Compared with UP,the plantation of Spartina anglica significantly decreased the concentration of C_(8–14) and tricyclic PAHs. Furthermore, the application of BC and RMB alleviated the toxicity of petroleum hydrocarbons to Spartina anglica via improving plant growth with increasing plant height, root vitality and total chlorophyll content. High-throughput sequencing result indicated that rhizosphere microbial community of Spartina anglica was regulated by the application of BC and RMB, with increase of bacteria and plant mycorrhizal symbiotic fungus in biochar and RMB amended soil.     

焉耆盆地石油勘探开发水污染应急管理系统研究

通过对石油开发应急管理系统分类及内容分析研究,结果焉耆地石油开发特点,提出焉耆盆地石油勘探开发水污染应急管理系统应具备的内容和功能,为焉耆盆地和其它区域石油开发污染控制提供了参考。     

便携式GC法测定石油污染地地下水中苯、乙苯和二甲苯

采用便携式气相色谱法测定石油污染地地下水中苯、乙苯和二甲苯,通过试验选择出测定的最佳色谱条件和适宜内标物,并对样品平衡时间、NaCl用量、取样后VOA瓶中液-气体积比等条件进行优化。试验表明,该方法在0 mg/L~2.00 mg/L范围内线性良好,相关系数均0.98;方法检出限为0.05 mg/L~0.15 mg/L。用该方法和吹扫捕集-气相色谱/质谱联用法同时测定实际水样,两种方法测定结果具有良好的一致性。     

使用OCMA—350非分散红外测油仪测量水或废水中石油类的探讨

本文初步探讨了使用OCMA－350非分散红外法测定水或废水中石油类过程中萃取剂CCl4的预处理与OCMA-350测油仪的使用。     

兰州市治理大气污染的探索与实践

兰州市在推进大气污染治理的实践中进行的有益的探索,为全国大气污染治理提供了宝贵的借鉴和经验。治污成就主要体现在环境质量改善、优良天数增多、减排效果明显、发展环境优化、民心得到凝聚。兰州市突破性地摘掉大气污染的“黑帽子”,主要作法包括多管齐下、对症下药、源头管控、网格管理、疏堵结合、分类施策等。兰州治理大气污染的实践经验兰州市大力治污的经验,也为建设美丽中国提供了有力借鉴。     

中石油企业可接受风险标准初步研究

本文根据可接受风险标准的确定方法和制定原则,提出了中石油企业可接受风险标准,包括员工个人可接受风险标准和员工社会可接受风险标准。     

Engineered in situ bioremediation of a petroleum hydrocarbon-contaminated aquifer: assessment of mineralization based on alkalinity, inorganic carbon and stable carbon isotope balances

A concept is proposed to assess in situ petroleum hydrocarbon mineralization by combining data on oxidant consumption, production of reduced species, CH₄, alkalinity and dissolved inorganic carbon (DIC) with measurements of stable isotope ratios. The concept was applied to a diesel fuel contaminated aquifer in Menziken, Switzerland, which was treated by engineered in situ bioremediation. In the contaminated aquifer, added oxidants (O₂ and NO₃⁻) were consumed, elevated concentrations of Fe(II), Mn(II), CH₄, alkalinity and DIC were detected and the DIC was generally depleted in ¹³C compared to the background. The DIC production was larger than expected based on the consumption of dissolved oxidants and the production of reduced species. Stable carbon isotope balances revealed that the DIC production in the aquifer originated mainly from microbial petroleum hydrocarbon mineralization, and that geochemical reactions such as carbonate dissolution produced little DIC. This suggests that petroleum hydrocarbon mineralization can be underestimated if it is determined based on concentrations of dissolved oxidants and reduced species.