CO_2驱地面采输系统缓蚀阻垢剂优选研究

CO_2驱提采技术因其诸多优点得到了广泛应用,但同时也带来了严重的地面采输系统腐蚀结垢风险。为此,分别采用电化学测试方法和静态阻垢法对油田常用的缓蚀剂和阻垢剂进行筛选,对优选的缓蚀剂和阻垢剂进行配伍性和协同性测试后,复配出效果优异的复合缓蚀阻垢剂,最后采用失重法和模拟工况阻垢率测试评价复合缓蚀阻垢剂的综合防护性能。筛选出的缓蚀剂和阻垢剂在55℃、常压下,饱和CO_2的模拟地层水中对采输系统典型钢材20钢的缓蚀率达93.06%,阻垢率达95.18%;将筛选的缓蚀剂和阻垢剂复配后,在模拟工况下,复合缓蚀阻垢剂加量500 mg/L时20钢的腐蚀速率控制在0.045 mm/a以内,阻垢性能满足油田控制指标。研究结果表明,复配的复合缓蚀阻垢剂对CO_2驱地面采输系统具有较好的防护作用,能保证其安全运行和生产。     

二氧化碳驱采油井缓蚀阻垢剂的复配实验研究

针对西部某油田注CO_2驱腐蚀结垢的特点,选用油田普遍使用的咪唑啉、季铵盐、酰胺盐、膦酸盐缓蚀剂以及氨基三亚甲基膦酸和聚天冬氨酸阻垢剂进行复配实验研究,用电化学测试方法和静态阻垢测试实验优选出性能良好的缓蚀剂和阻垢剂单剂,对所选的缓蚀剂和阻垢剂在总质量浓度240mg/L下进行最优配比实验后,采用失重法、模拟工况测试阻垢率以及扫描电镜(SEM)评价复合缓蚀阻垢剂的防护效果。实验结果表明:通过单剂筛选得出的缓蚀剂和阻垢剂在60℃饱和CO_2模拟地层水中对N80碳钢的缓蚀率高达94.13%,阻垢率高达93.98%;在总质量浓度为240mg/L时,缓蚀剂与阻垢剂按2∶1的质量比复配后的试剂,缓蚀率达91.98%,阻垢率达91.10%;在模拟实际最苛刻的生产工况下,复合缓蚀阻垢剂的防腐防垢均能满足油田控制指标。研究表明,膦酸盐和聚天冬氨酸复配的缓蚀阻垢剂可以抑制CO_2驱采油井的腐蚀结垢问题。     

含CO2高温蒸汽环境中低合金钢耐腐蚀性能评价

利用高温高压釜模拟CO_2辅助蒸汽驱注气井筒工况,在CO_2分压为2 MPa,温度为160~220℃条件下,对低合金钢进行了失重挂片腐蚀试验,得到了不同温度条件下管材的腐蚀速率,并利用扫描电镜和能谱仪观测管材在不同温度条件下的腐蚀形貌及产物组成。实验结果表明:在160~220℃范围内,随着温度的升高,低合金钢的腐蚀速率呈现先降低后增大的变化趋势,且均在160℃时腐蚀速率最高;在实验条件下,两种低合金碳钢的均匀腐蚀速率均小于油田控制指标0.076mm/a,满足注气井井筒管柱的腐蚀控制要求。     

CO_2和O_2的分压比对N80套管钢氧腐蚀行为研究

电化学阻抗谱,利用高温高压釜失重实验以及扫描电镜等技术,研究了CO_2和O_2分压对N80钢在饱含CO_2和O_2气体的吉林油田采出水中的腐蚀行为影响,以期为减氧空气驱的大规模开展提供理论基础。     

腰英台油田二氧化碳驱油系统高效缓蚀剂筛选与评价

腰英台油田开展二氧化碳驱油提高采收率先导试验,需要采取有效的二氧化碳腐蚀防护措施。加注缓蚀剂是解决二氧化碳腐蚀的有效方法之一。室内采用挂片失重法,并模拟试验区的工况条件,对20种缓蚀剂样品进行了缓蚀试验评价,筛选出HS-20高效缓蚀剂样品;同时应用EDS能谱分析方法初步揭示了其腐蚀产物特征。试验结果表明,当HS-20缓蚀剂质量浓度为50mg／L,温度90℃,其缓蚀率可达95％以上。     

抗CO_2腐蚀环保型油基环空保护液研究

由于丝扣等连接件的密封性问题的存在,油气田开发过程中的CO_2不可避免会渗入环空,进而产生严重的CO_2腐蚀,有必要研制出一种环保高效的油基环空保护液以延长管柱服役寿命。首先,从6种油中优选出经济环保的白油作为基础油,其稠环芳烃含量为0. 3%,远低于欧盟2005/69/EC指令中要求的3%,符合环保要求;其次,通过配伍性实验对9种缓蚀剂进行油溶性筛选,并利用电化学方法对配伍性良好的缓蚀剂进行测试,筛选出了缓蚀性能较好的咪唑啉类缓蚀剂及其最佳注入浓度1 000 mg/L,形成一种环保型油基环空保护液,其配方为白油+1 000 mg/L咪唑啉类缓蚀剂;然后,对该油基环空保保护液进行理化性能测试,结果表明,其闪点不低于160℃、倾点为-37℃、密度为0. 82 g/cm~3,符合安全生产要求;最后,采用高温高压釜模拟注CO_2井环空腐蚀工况环境,对该油基环空保护液进行防护效果评价,实验结果表明,P110钢的在CO_2相中的腐蚀速率降到0. 05 mm/a以下,在油相中的腐蚀速率降到0. 01 mm/a,缓蚀率可达95%以上。研究结果表明,新型环保型油基环空保液具有良好的防护效果和耐温性能,符合环保要求,可用于CO_2腐蚀工况环空管柱的防护。     

水溶性缓蚀剂在中低二氧化碳气井的应用

中国石油天然气股份有限公司长庆油田分公司上古气井具有中低二氧化碳、高矿化度及介质pH值变化大的腐蚀特点,同时气井井筒温度多处于腐蚀行为和机理多变的敏感区(60～100℃),这些特点对缓蚀剂的适应性提出了较高的要求。该文主要针对上述腐蚀环境的行为特征,通过缓蚀剂物化性能、相关配伍性、电化学性能、高温高压及现场井筒挂片质量损失分析,研究开发出适合中低CO2、高矿化度水气井腐蚀环境的水溶性缓蚀剂(HGCQ),具有水溶性良好,高温及低温稳定性优良,与甲醇及甲基二乙醇胺(MDEA)配伍性好的特点。室内研究了该缓蚀剂的缓蚀机理为阳极抑制型,确定其现场最佳加注质量浓度为300 mg/L。进行了模拟占古气井筒腐蚀环境的高温高压腐蚀试验和现场一口气井3个月的质量损失挂片测试,结果表明该缓蚀剂缓蚀效果明显,可以有效控制气井管柱的腐蚀。     

注水井筒高温高压缓蚀阻垢剂的研究应用

针对油田低渗透油藏注水井筒水质变化及存在腐蚀结垢问题,在分析现场垢样成分和筛选评价现有缓蚀阻垢剂的基础上,研制了具有良好高温缓蚀性能的含氮杂环类缓蚀剂和喹啉季胺盐类化合物,并与有机磷酸类阻垢剂复配,形成高温高压缓蚀阻垢剂,在室内150℃、4MPa条件下缓蚀率和阻垢率均达到90%以上。该药剂在纯梁樊家站注水系统应用后,现场缓蚀率达91.1%,阻垢率达95.6%。     

超临界CO2缓蚀阻垢剂的合成及性能评价

针对高矿化度低渗透油藏CO_2驱油过程中超临界CO_2腐蚀结垢问题,合成一种由苯甲酸硫脲基咪唑及磷酸酯基咪唑啉、喹啉季铵盐和聚环氧琥珀酸盐为主要成分构成的缓蚀阻垢剂CQ-HS。利用高温高压实验、电化学和阻垢率评价方法,在超临界条件下研究了CQ-HS的抗CO_2腐蚀性和阻垢性能。研究结果表明,在80℃、CO_2分压9.0 MPa条件下,添加200 mg/L的缓蚀阻垢剂CQ-HS后,碳钢的腐蚀速率降为0.068 mm/a,具有良好的缓蚀性能;当缓蚀阻垢剂CQ-HS加量为200 mg/L时,其对硫酸钡锶垢的阻垢率可以达到80%以上。在超临界CO_2条件下,CQ-HS缓蚀阻垢剂同时具有缓蚀和阻垢性能,可实现一剂多用的目标。图9表1参15     

高温CO2/O2体系中P110钢的腐蚀与防护研究

海上油田在进行多元热流体热采过程中遇到了严重的管柱腐蚀问题。为解决隔热油管腐蚀问题,文章采用动态挂片法对CO2/O2体系中P110钢的高温腐蚀规律进行了研究,并且评价了一种咪唑啉缓蚀剂的缓蚀效果。结果表明,在40℃～280℃范围内,P110钢的腐蚀速率出现两个极大值,分别在60℃和180℃;高温CO2/O2体系中,少量的氧气(分压0.02MPa)即可极大地加速P110钢的腐蚀;CO2分压超过2MPa后P110腐蚀速率明显加快;所用缓蚀剂在浓度750mg·L-1时可将腐蚀速率降低至0.10772mm·a-1,缓蚀率达94.17%。应用高温缓蚀剂防腐工艺后,注热后起出的隔热油管未出现明显腐蚀,基本满足高温条件下的多元热流体热采防腐要求。     

H6P2W18O62/MCM-48催化剂的制备、表征及催化绿色合成己二酸

以MCM-48为载体,通过浸渍法制备了H6P2W18O62/MCM-48催化剂,并采用FT-IR、XRD、SEM、EDS对催化剂进行表征。以微波促进30%(质量分数)H2O2氧化环己酮合成己二酸反应为探针,考察了H6P2W18O62/MCM-48的催化性能,并通过正交实验确定了优化的工艺条件。结果表明,采用H6P2W18O62负载量40%的H6P2W18O62/MCM-48催化剂,在优化的合成己二酸的工艺条件下,即催化剂质量分数(以环己酮质量计)5.1%、n(C6H10O)∶n(H2O2)∶n(H2C2O4.2H2O)=100∶450∶1.88、反应温度95℃、微波功率300 W、反应时间3.5h,己二酸收率可达81.3%;催化剂重复使用5次,己二酸收率仍可达到64.6%。     

Petroleum Hydrocarbons Extraction Efficiency of Carbon Tetrachloride and Trichlorotrifluoroethane: A Comparative Study

Abstract

Petroleum hydrocarbons (PHC) contaminated water samples, prepared in laboratory, were analyzed using infrared spectroscopy to compare PHC extraction efficiency of carbon tetrachloride (CCl₄) and trichlorotrifluoroethane (C₂Cl₃F₃) solvents. The comparison of the results illustrated that PHC extraction efficiency of CCl₄ was greater than C₂Cl₃F₃. The higher extraction efficiency of CCl₄ was ascribed to its more non-polar nature and higher polarity index. This study supported the selection and use of CCl₄ for extraction and quantification of PHC of groundwater samples of the projects carried out in the department.     

Nanocatalysts: Effect of Active-phase and Promoter on Catalytic Properties and Performance in the Hydrodesulfurization Reaction

The influence of various amounts of phosphorus addition on performance of NiMoP/Al₂O₃ and CoMoP/Al₂O₃ nanocatalysts was examined in hydrodesulfurization of thiophene. The nanocatalysts were synthesized via sonochemical technique. The prepared samples were characterized by XRD, FESEM, BET, and FTIR analysis. The catalytic activity in hydrodesulfurization reaction was investigated in a batch stirred slurry reactor at 160°C and atmospheric pressure. The characterizations confirmed highly dispersion of active phase and formation of amorphous AlPO₄ species on the support surface. The results obtained from thiophene hydrodesulfurization showed the nanocatalysts contained 1 wt% of phosphorus had the highest activity. The CoMoP/Al₂O₃ and NiMoP/Al₂O₃ nanocatalysts with optimum phosphorus loading nearly gave 100% conversion of thiophene, so that the sulfur compound concentration in final solution was less than 50 ppm.     

Nanosized Platinum-Loaded H-ZSM-5 Zeolite Catalysts for n-Hexane Hydroconversion

Abstract

A series of nanosized platinum-containing catalysts was successfully loaded on/in zeolite H-ZSM-5 via exchanging the zeolitic proton with platinum from Pt tetramine dichloride complex. Another series of Pt/H-ZSM-5 catalysts was prepared via wet impregnation of H₂PtCl₆ solution for comparison. The latter series was found to produce lower Pt dispersion. Pt dispersion was determined by H₂ chemisorption. Catalyst characterization via ammonia temperature-programmed desorption (TPD), temperature-programmed reduction (TPR), and transmission electron microscopy (TEM) was examined for all catalysts and showed large differences in particle sizes. The data on n-hexane reactions of the catalysts of both series confirmed the formation of Pt nanoparticles in the exchanged catalysts. The relatively lower density and strength of acid sites acquired by Pt-exchanged catalysts contributed to this difference; stronger acid sites in the impregnated catalysts are in favor of hydrocracking reactions, which inhibit isomerization selectivity.     

Characterization of Al2O3–ZrO2 Mixed Oxide Supported Mo Hydrotreating Catalyst

Abstract

A series of molybdenum catalysts supported on Al₂O₃–ZrO₂ mixed oxide containing 50% ZrO₂ and 50% Al₂O₃ were prepared by incipient wetness technique and characterized by BET surface area, X-ray diffraction, temperature programmed reduction and oxygen chemisorption. The catalytic activities for hydrodesulphurization (HDS), hydrogenation (HYD), and hydrocracking (HYC) were determined using thiophene, cyclohexene, and cumene as model compounds, respectively. Results indicate that up to 8 wt% Mo loading, the catalyst is well dispersed and crystallite growth occurred beyond this loading. Also both oxygen uptake and catalytic activities increase with Mo loading up to 8 wt% and then decreases at higher loading. A linear correlation was obtained between oxygen uptake and all catalytic activities and the correlation coefficients obtained suggest that the order of catalytic activities for HDS, HYD, and HYC is: HDS > HYD > HYC. Furthermore, the catalytic activities of the mixed oxide supported catalyst for HDS, HYD, and HYC were higher than those supported on pure alumina and pure zirconia. The incorporation of 3% Co on 8% Mo catalyst was determined to result in enhanced activity for HDS, HYD, and HYC.     

复合SiO2-WO3催化剂的制备、表征及氧化脱除苯并噻吩性能

 采用溶胶-凝胶法制备了SiO₂-WO₃催化剂,并采用XRD、FT-IR、BET、TG-DTA等方法对催化剂进行表征。以苯并噻吩(BT)为模型化合物,H₂O₂为氧化剂,考察了催化剂的活性元素、制备方法、n(W)/n(Si)和焙烧温度对其催化氧化脱硫活性的影响。结果表明,W的引入降低了SiO₂的比表面积,SiO₂-WO₃催化剂中W的主物相为WO₃。在以W为活性组元,且n(W)/n(Si)为0.1时,500℃焙烧得到的SiO₂-0.1WO₃催化剂具有最好的催化脱硫活性。在模拟油20 mL、催化剂SiO₂-0.1WO₃用量0.04 g、n(H₂O₂)/n(S)为15.9、乙腈/模拟油体积比0.3、65℃反应60 min的条件下,苯并噻吩模拟油脱硫率可达99.3%。     

Production of olefins from syngas over Al2O3 supported Ni and Cu nano-catalysts

The most important products that can be produced from syngas are methanol, dimethyl ether and light olefins (ethylene and propylene). The light olefins are the most important syngas products, because many of the chemicals are produced from them. The aim of this work was to study the olefins production from syngas over Al₂O₃-supported Ni-Cu nano-catalysts. In addition, the effect of various factors such as catalyst on olefin production and CO conversion has been investigated. The concentration of heavier olefins (C5) was greater than the remaining olefins, since the rate of reactions must be increased to form C1 to C4. In the case of a Ni/Al₂O₃ catalyst, C1 and C4 was initially increased and then decreased with an increase in Ni loading from 0% to 15%.     

Design of Catalyst Support for Deep Hydrodesulfurization of Gas Oil

Abstract

Alumina-silica (Al₂O₃-SiO₂) composite supports were examined to find the optimum state of support (i.e., composition and morphology). SiO₂ content in the Al₂O₃-SiO₂ support induced a shift of the main peak to higher frequency ascribed to an increased amount of Mo₈O₂₆ ^4?. A 75 wt% Al₂O₃-25 wt% SiO₂ support had homogeneously dispersed alumina particles of smaller size with high crystallinity. Hydrodesulfurization (HDS) of straight-run gas oil and its conventionally hydrotreated straight-run gas oil was performed over NiMo sulfides supported on Al₂O₃-SiO₂ composites. The high crystallinity of NMASA2-27 may be related to the high HDS and hydrogenation activity of NiMo sulfides due to its moderate interaction with the alumina surface.     

氧化镁改性微米TS-1催化丙烯环氧化

合成了粒径在1~2 μm的廉价微米TS-1,并经MgO改性,杀灭其上少量的酸中心;采用SEM、XRD、BET对MgO改性前后的TS-1进行了表征,并考察了其在甲醇溶剂体系丙烯环氧化的催化性能。结果表明,TS-1催化剂经MgO改性后,可以显著提高其催化丙烯环氧化反应的环氧丙烷(PO)选择性,减少副反应的发生;在最优化反应条件CH₂O₂ =1.0 mol/L, θ = 60℃, t = 60 min, p_C3↓H6↓ = 0.6 MPa,以及按每1 gTS-1需80 mL CH₃OH的比例下,H₂O₂转化率达到99.5%,环氧丙烷选择性达到96.7%,环氧丙烷收率比未改性的微米TS-1也有明显提高。     

Application of Light Hydrocarbon (C7+) and Biomarker Analyses in Characterizing Oil from Wells in the North and North Central Sinai,Egypt

Abstract

Seven representative oil show samples from wells in the north and north central Sinai have been characterized by means of a variety of organic geochemical techniques (C₇ hydrocarbon and biomarker analyses), to illustrate origin, differences, and similarity among oils. These oils were obtained from Cretaceous and Jurassic reservoirs. The C₇ oil correlation star diagram (OCSD) suggests closely related oils, derived mainly from similar source rocks, while the C₇ oil transformation star diagram (OTSD) and C₇ light hydrocarbon analyses indicate a minor degree of transformation of some oils, as Misri-1, Halal-1, and Nakhl-1 oils were subjected to evaporative fractionation. Moreover, the studied oils show no sign of water washing and biodegradation. Molecular characteristics suggest pre-Tertiary shales and carbonate source rocks, deposited under a saline oxic environment, rich in terrigeneous organic sources with significant bacterial and algal input. Since the studied oils are of mixed marine and terrestrial origin, C₇ signature of these oils is not representative of their origin and should be supported by other geochemical evidence (e.g., biomarkers) to predict their origin.