Accurate prediction of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) emissions from municipal solid waste incineration flue gas is limited by high-dimensionality and small offline datasets, resulting in unsatisfactory prediction accuracy and generalization ability of traditional machine learning models. To address this small-sample bottleneck, this study proposes an interpretable framework based on stepwise virtual sample generation (VSG). Different from the traditional methods, this framework refuses to generate all virtual samples at once based on the initial model, and instead generates only 50 virtual samples at each step and achieves iterative optimization of the prediction model, which breaks the limitation of the initial model on the quality of virtual samples. Comprehensive validation experiments show that stepwise VSG has superior effectiveness and robustness. The generated virtual samples demonstrate both validity and cross-model applicability in reducing prediction errors, allowing the root mean square error and mean absolute percentage error to be reduced by 60.52 % and 68.47 %, respectively. Meanwhile, the performance limits and the optimal virtual sample size exhibit exponential dependence on the original sample size. These relationships provide a scientific modeling strategy and quantitative monitoring budget for the application of the framework in practical engineering. Finally, Shapley additive explanation and Partial Dependence Plot analyses reveal a multi-parameter synergistic control strategy that has the theoretical potential to reduce PCDD/Fs emissions to 0.023 ng TEQ/Nm3. The proposed framework shows considerable potential in the quantitative development of high-accuracy prediction models and the assessment of emission control strategies under small-sample conditions, thereby supporting effective PCDD/Fs management.

The efficient and safe disposal of radioactive waste remains a critical global challenge. While plasma technology is widely applied for its efficiency and safety, studies on secondary pollutant emissions remain limited. This research investigated emissions of chlorobenzenes (CBzs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during the disposal of simulated radioactive waste from a pilot-scale high-temperature plasma melting incinerator in China under different waste conditions with rubber, polyvinyl chloride (PVC), and waste resin. Total concentrations of CBzs and PCDD/Fs in stack gas ranged from 3.445 to 117.192 mu g/Nm3 and 0.006-0.408 ng TEQ/Nm3, respectively. High-chlorine wastes such as waste resin, PVC, and rubber increase the emissions of CBzs and PCDD/Fs, while co-adding PVC and rubber reduces PCDD/Fs emissions due to synergistic effect. Dominant congeners included 2,3,7,8-TCDD, 2,3,4,7,8-PeCDF, and HCBz. Furthermore, correlation analysis exhibited a markedly linear correlation between 1,4-DCBz and PCDD/Fs, and the differential pressure between the quench tower and filter correlated positively with PCDD/Fs, particular when PVC and rubber were added. This research not only explores the impact of waste type and parameters of air pollution control devices on PCDD/Fs emissions, but also provides significant data to enhance the safe disposal of radioactive waste and improves plasma technology processes.

Existing online monitoring system for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), technically named Thermal Desorption-Gas Chromatography-Tunable Laser Ionization-Time of Flight Mass Spectrometry (TD-GC-TLI-TOFMS), has been applied in several incinerators in China. TD-GC-TLI-TOFMS can realize rapid detection of PCDD/Fs emissions from incineration sources. However, the long-term measurement of unclean flue gas will pollute the instruments in TD-GC-TLI-TOFMS, and interfere with the peak output of the target 1,2,4-trichlorobenzene (1,2,4-TrCBz). In this study, Deans switch (DS) was utilized for the first time in an online monitoring system for PCDD/Fs to separate 1,2,4-TrCBz signal from impurity signals, which improved the antiinterference capability of the system. Laboratory standard gas experiments showed that after adding a DS device between GC and TLI pulse valve, when the pressure set in DS was 4 psi and switched before or near the peak output of 1,2,4-TrCBz, the change of 1,2,4-TrCBz signal intensity was minimal. The impurities near the target peak were removed, and TLI-TOFMS was highly stable during continuous measurement. Moreover, the maximum intensity peak time of 1,2,4-TrCBz was stable after using DS in different switching time intervals. When connecting DS to TD-GC-TLI-TOFMS for field validation on the tail flue gas of a municipal solid waste incinerator (MSWI), results showed that a better 1,2,4-TrCBz signal could be obtained with a 69.52 % reduction of impurity peaks at the moments closer to the target peak. Furthermore, DS improved the sensitivity of the system to low concentration variations of 1,2,4-TrCBz in the flue gas. The robust system developed in this study can be better applied to incineration factories with poor combustion or suboptimal purification technology, facilitating online PCDD/Fs monitoring.

Abstract Santos basin of Brazil is a hot area of oil and gas exploration and development in the world. Many sub-salt oil fields have been discovered in recent years. The reservoirs are mainly composed of microbial carbonate rocks with strong heterogeneity, which has developed a variety of storage space types. The fluid is complex with high gas oil ratio and CO2 content. The re-injection of produced gas brings uncertainty to the production performance and the stability of facilities. The project investment is huge due to many factors such as deep-water, deep buried and far away from the coastline. The complexity of reservoir and high investment of project make the economic and effective development of reservoir full of great challenges. This paper describes the development strategies of Brazil’s sub-salt deep-water oilfield and the main successful methods to maximize recovery and profits under uncertain conditions. It includes the following three aspects: (1) abundant information acquisition to reduce the main uncertainties; (2) development plan with robustness and flexibility to deal with potential risks; (3) multidisciplinary comprehensive research to evaluate reservoir mode and development mode.

利用激光电离飞行时间质谱在线检测二英系统对某生活垃圾循环流化床焚烧炉烟气中二英排放进行连续在线监测,通过调整焚烧工况,探究不同工况对二英排放的影响.结果表明:活性炭用量从10kg/h提升至30kg/h,对二英浓度降低效果并不显著,二英稳态浓度仅下降13.33％;烟气中投用抑制剂,可使异常状况导致的高浓度二英排放能更快地恢复至正常低浓度排放水平;减少入炉垃圾量,启用辅燃,二英排放低且稳定,其毒性当量(TEQ)浓度均值为0.028 ng/m3.稳定焚烧工况,使垃圾充分燃烧,从源头减少 二英生成,是控制二英排放较有效的方法;二英与14种锅炉运行参数之间的相关性较弱,其排放是一个综合性的问题,与诸多因素有关,不能用单一参数进行衡量.

伴生气回注逐渐成为海上油田兼顾气处理和提高采收率的重要技术之一.为揭示海上深水目标油田特殊油藏条件下合理开发方式和参数,开展细管驱替、高温高压长岩心驱替等系列实验,重点研究不同驱替方式和驱替参数对开发效果的影响.实验结果表明:在地层原始条件下,目标油田伴生气(主要成分为二氧化碳和甲烷)回注可形成混相气驱.在目标油田储层物性条件下,水气交替驱最终驱油效率为83.0％,相比纯水驱和纯气驱驱油效率分别提高39.8％和9.8％.水气交替注入在大幅提高驱油效率同时,有效延缓见水时间(约为纯水驱的4倍)和见气时间(约为纯气驱的2倍).水、气注入顺序对最终驱油效率无明显影响,但实验条件下优先注气在驱替初期表现出更高的产油速度.实验参数范围内,目标油田最优注入段塞大小为0.1倍烃孔隙体积(HCPV),最优气水比为1:2.本实验研究结果可为目标油田开发方案设计及现场应用提供有益指导.

Due to the influence of long-term waterflooding, the reservoir physical properties and percolation characteristics tend to change greatly in offshore unconsolidated sandstone reservoirs at ultrahigh water-cut stage, which can affect the remaining oil distribution. Remaining oil characterization and proper development strategy-making are of vital importance to achieve high-efficiency development of mature reservoirs. The present numerical simulation method is difficult to apply in reservoir development due to the problems of noncontinuous characterization and low computational efficiency. Based on the extended function of commercial numerical simulator, the time-varying equivalent numerical simulation method of reservoir physical properties was established, and the research of numerical simulation of X offshore oilfield with 350,000 effective grids was completed. The results show that the time-varying reservoir properties have a significant impact on the distribution of remaining oil in ultrahigh water-cut reservoir. Compared with the conventional numerical simulation, the remaining oil at the top of main thick reservoir in X oilfield has increased by 18.5% and the remaining oil in the low-permeability zone at the edge of the nonmain reservoir has increased by 27.3%. The data of coring well and the implementation effect of measures in the X oilfield are consistent with the recognition of numerical simulation, which proves the rationality of numerical simulation results. The new method is based on a mature commercial numerical simulator, which is easy to operate and has reliable results.

For the long-term operation of municipal solid waste incineration (MSWI), online monitoring and feedback control of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) can be used to control the emissions to national or regional standards. In this study, 500 PCDD/F samples were determined by thermal desorption gas chromatography coupled to tunable-laser ionization time-of-flight mass spectrometry (TD-GC-TLI-TOFMS) for 168 h. PCDD/F emissions range from 0.01 ng I-TEQ/Nm3 to 2.37 ng I-TEQ/Nm3, with 44% of values below 0.1 ng I-TEQ/Nm3 (the national standard). In addition, the temperature of the furnace outlet, bed pressure, and oxygen content are considered as key operating parameters among the 13 operating parameters comprising four temperature parameters, four pressure parameters, four flow parameters, and oxygen content. More specifically, maintaining the furnace outlet temperature to be higher than 800 °C, or bed pressure higher than 13 kPa, or the oxygen content stably and above 10% are effective methods for reducing PCDD/F emissions. According to the analysis of the Pearson coefficients and maximal information coefficients, there is no significant correlation between operating parameters and PCDD/F I-TEQ. Only when there is a significant change in one of these factors will the PCDD/F emissions also change accordingly. The feedback control of PCDD/F emissions is realized by adjusting the furnace outlet temperature, bed temperature, and bed pressure to control the PCDD/F to be less than 0.1 ng I-TEQ/Nm3.

2020年12月,全球首例针对二噁英在线检测的团体标准《生活垃圾焚烧烟气二噁英激光电离飞行时间质谱在线检测系统技术要求》(T/CAEPI 28-2020)正式发布.文章针对新发布的团体标准,详细解读了制定的背景、意义与作用,重点分析了关键技术内容及参数要求,可对该标准的理解、应用与推广起到积极的作用.

The current derived models for predicting polychlorinated dibenzo-p-dioxins and -furans (PCDD/F) emissions from incineration can only be applied to a specific incinerator due to high deviation or systematic errors. And the models fail to provide quantized guidance for the operation of full-scale municipal solid waste incinerators. To address the problem, explainable Bayesian support vector regression (E-BSVR) has been established to generalized predict and maximumly reduce the PCDD/F emissions. First, forty-two PCDD/F samples were determined from a whole year experiment in a full-scale incinerator. Meanwhile, 1,2,4-trichlorobenzene(1,2,4-TrCBz), carbon monoxide, sulfur dioxide, oxynitride, particulate matter, fluoride, and hydrogen chloride were measured, as input features. Second, after box-cox transformation normalization, and hyperparameters tuning, the R-Squared and root mean square error (RMSE) of the proposed method are 0.983 and 0.044, exhibiting high accuracy. The high accuracy (R-Squared = 0.992) and generalization are also proven on the dataset with high PCDD/F emissions. Then, the performances of BSVR are compared with kernel ridge regression, multiple linear regression, and unary linear regression, indicating afar smaller RMSE of BSVR. Finally, the optimal operating parameters are calculated through local interpretable model-agnostic explanations and the partial dependence plot. Results indicate that reducing the content of organic chlorine in municipal solid waste and inhibiting the deacon reaction are important methods for reducing PCDD/F emissions. The optimal operating parameters for the maximal reduction of PCDD/F emissions are 1,2,4-TrCBz < 0.098 ug/m3, fluoride > 0.452 mg/m3. As a whole, the E-BSVR method can be used as a reliable and accurate approach for the prediction and reduction of PCDD/F emissions.

In the development of deep water carbonate oil field, due to economic factors, it is usually used to extend well test to evaluate reservoir connectivity, estimate reservoir boundaries and connectivity volume, analyze long-term production capacity of oil wells, reduce the risk of production wells in the later period, and provide oilfield development decisions for operators. In this paper, through interpretation of extended test data of a deep-water carbonate reservoir in Brazil, the horizontal and vertical connectivity of the reservoir is evaluated, as well as the vertical and horizontal heterogeneity of the reservoir. Meanwhile, through long-term production data, the productivity of the carbonate reservoir is analyzed, it provides parameters for determining the productivity of new wells. The efficient application and interpretation of extended test data is of great significance to the recognition and productivity evaluation of carbonate reservoirs.

The composition of the fuel and operational conditions change dramatically under the long-term operation of municipal solid waste incineration (MSWI). Therefore, it is difficult to provide effective rapid feedback to control PCDD/F emissions, presenting as International Toxic Equivalent Quantity (I-TEQ). To address this problem, a PCDD/F emission prediction method is developed, based on formation pathway identification clustering (FPIC) and Box-Cox transformation (BCT). Meanwhile, 1,2,4-trichlorobenzene is measured by the thermal desorption gas chromatography coupled to tunable-laser ionization time-of-flight mass spectrometry (TD-GC-TLI-TOFMS). In the method, FPIC includes de novo synthesis, chlorobenzene(CBz)-route synthesis, chlorophenol (CP)-route synthesis, and the chlorination of dibenzofuran (DD) or dibenzodioxin (DF). The PCDD/F emission data was divided into Cluster 1 (I-TEQ>0.1 ng/Nm(3)) and Cluster 2 (I-TEQ<0.1 ng/Nm(3)) by FPIC due to PCDD/F in Cluster 1 main from CProute and PCDD/F in Cluster 2 main from de novo synthesis and CBz-route synthesis. Also, the BCT was used to transform the I-TEQ and 1,2,4-trichlorobenzene data and to construct effective models. The accurate and precise PCDD/F emissions are predicted with the vast majority of error percentage within [ similar to 40%, 40%], and errors within [similar to 0.126, 0.016] I-TEQ (ng/Nm(3)). The absolute value of the relative difference between predicted I-TEQ and measured I-TEQ (vertical bar RD vertical bar) of the linear model constructed by the method has a significant reduction to 20.28%. FPIC and BCT can be used as an effective method to online predict PCDD/F emission in long-term operation thereby allowing the rapid operational feedback to control PCDD/F emission from the incinerator. (C) 2021 Elsevier Ltd. All rights reserved.

巴西桑托斯盆地M油田盐下巨厚湖相碳酸盐岩储层发育硅化作用,目前尚未有相关研究探讨其成因机制.为此,综合利用岩心、薄片、流体包裹体测试和X射线荧光分析等资料,对M油田不同硅化作用特征开展成因探讨,并在此基础上分析其对储层的影响.研究结果表明:硅化作用在M油田较为普遍,超过一半样品受硅化作用影响,但仅有17％的样品属于中-强硅化作用.硅化作用成因类型包括3种,分别为沉积型、早期成岩型和热液型.沉积型和早期成岩型硅化作用对储层物性影响有限.综合证据显示,强热液硅化层段与侵入岩空间分布关系密切;同时其主要氧化物含量介于侵入岩和碳酸盐岩围岩之间,呈二者混染特征,且流体包裹体均一温度较高(87～193℃),证明热液硅化作用为岩浆期后热液所致.岩浆期后热液倾向于沿碳酸盐岩地层内部的断层、裂缝、不整合面等构造薄弱带以及与这些薄弱带相连通的高基质孔隙带流动,使储层发生强烈硅化作用.当硅质含量大于10％,对储层物性产生较大影响.

为进行油藏数值模拟,需要先对细网格地质模型的属性进行粗化,粗化过程会产生信息损失,为最大程度地减小粗化过程中的地质信息的损失,需要对现有的粗化方法进行筛选.通过文献调研,深入分析了目前常用的渗透率粗化方法的粗化原理,并对比了不同粗化方法的优缺点,发现不同粗化方法适用条件不同,并且不同粗化方法对于属性粗化结果的影响不同.以Libra油田为例进行了机理模型研究,利用不同粗化方法对细模型渗透率分别进行粗化,并对细模型及各粗化后的模型分别进行数值模拟.选取含水率和日产油率作为对比参数,通过对数值模拟结果的对比进行了粗化方法优选.最后确定最适合研究区的粗化方法为流动法,其粗化结果更接近细模型.

美洲深水油气田已成为世界石油行业的热点之一,然而受水深影响,勘探开发面临巨大挑战.中海油公司(简称中海油)自2013年进入巴西2000m深水油气领域以来,逐渐形成了特色的超深水油气田评价井部署决策技术、延长测试部署与设计技术、深水巨厚碳酸盐岩储层非均质性精细表征与方案优化技术,应用于L油田并成功实现首次采油.中海油建立了海外油气田开发类比大数据平台,为1500m至2000 m深水巴西C&V油田、墨西哥1&4油田的成功并购提供了技术保证.

对油藏连通模式作出合理判断是决定油田开发成功的关键因素之一.巴西X深水盐下油田发育复杂油水系统,在其油藏评价阶段难以通过常规开发手段快速、有效地落实油藏连通模式.为此,尝试采用一种新的开发策略 —— 延长测试(EWT),基于动静态结合分析方法,建立了X油田的"局部遮挡式"油藏模式.基于油田断层、隔夹层发育模式静态认识,结合测试目的,部署了"1注1采"测试井位.利用"垂向多层完井、错层观察,平面中央激动、全局部署"的压力监测设计技术和多情景模拟的工作制度优化技术,在2口EWT井的生产实践中成功获取了全油田多层段压力响应变化规律.

近年来,智能完井技术在全球范围内得到越来越广泛的应用,但目前成熟的商业数值模拟软件中并没有专门的智能完井模块,等效方法无法实现多种智能完井控制策略特别是积极控制策略的模拟,不能充分体现智能完井的增油效果.文章在广泛调研基础上,借助斯伦贝谢公司Petrel-RE软件和INTERSECT模拟器高级油田管理的相关功能,实现了不同智能完井控制策略的模拟,同时考虑现场实施中井下流入控制阀存在可靠性的问题,建立井下流入控制阀失效率模型,与智能完井数值模拟方法结合形成了智能完井技术实施效果的综合评价方法,并在巴西L油田进行了应用.

Taking production as the core indicator,a new concept of"operational efficiency"is put forward,based on which a new evaluation method for well production efficiency is introduced.On the basis of the classification of oil field production events,several principles for calibrated production calculation are summarized.Then,the clas-sified prediction method of oil well operation efficiency is conducted to guide the formulation of maintainable job content.This method shows distinct superiority at production forecast and oilfield management, and reflects the spirit of delicate oilfield management.

自2006年以来,巴西盐下深水区块连续取得重大勘探发现,成为重要的储量接替区,截至2017年6月,累计产油气17×108bbl.该地区水深高达2000m,地质背景和油藏条件复杂,油田经济有效开发难度大.总结了巴西盐下深水油田面临的主要开发风险,介绍了巴西国家石油公司在有效识别和把控风险方面形成的特色理念和做法,如经济有效的资料录取与油田评价、增加开发方案设计的适应性和灵活性、建立早期生产系统、分阶段开发等,这些举措是油田成功开发的关键.

深水油田勘探开发存在经验不足,深水环境及地下因素复杂多变、单井投资费用高企,以及项目成本回收压力大等挑战,简单复制陆上和浅海的勘探开发一体化模式已无法满足深水油田勘探开发的需要.为此引入地质工程一体化理念,综合考虑地下不确定性、时间要素和成本要素,提出一套适合深水油田的油藏评价及决策体系,并在此基础上开展评价模式、决策方法以及钻完井配套技术研究.在巴西盐下深水油田的评价实践表明,以分区评价为核心的“一体双轴”的评价模式和以信息价值为代表的深水油田评价井决策方法,将有利地推动深水油田的勘探开发一体化进程,缩短评价周期,进而实现油藏评价的效益最大化和评价决策的科学化.盐下钻完井配套技术的应用,大幅提高了钻井效率,在为开发井积累经验的同时,降低了钻井成本.地质工程一体化理念在巴西利布拉油田的应用,证明了地质工程一体化作业模式在深水油田以及油藏评价阶段的适应性,从而扩大了地质工程一体化的应用领域.