油田污水系统硫化氢的危害及其治理

油田地面系统因硫酸盐还原菌繁殖导致硫化氢不断增长,是长期注污水开发的油田所面临的普遍问题。简述了油田污水中硫化氢的危害以及常用的硫化氢去除和增长控制技术,并重点介绍了河南油田的三个应用实例:其一,采用两级普通曝气处理聚合物配制污水,在气水比(V/V)=1∶2时,残留硫化氢含量小于1 mg/L;其二,普通曝气与缓蚀杀菌剂结合控制腐蚀,单级曝气气水比(V/V)=1∶(7~10)的条件下,硫化氢含量从50~60 mg/L下降到5~10 mg/L,再添加FH-8型缓蚀杀菌剂25 mg/L,腐蚀率从1 mm/a下降到0.2 mm/a;其三,固相催化曝气氧化与生物抑制技术相结合,实现硫化氢的彻底去除和控制,用于高温聚合物驱油的污水配制聚合物,在气水比(V/V)=1∶1时,硫化氢含量从25 mg/L下降到0.5 mg/L以下,生物抑制剂则使沿程硫化氢增长量不超过0.5 mg/L。催化曝气氧化除硫与普通曝气除硫相比,具有曝气量小、除硫迅速彻底的优点。对于对硫化氢含量要求严格的系统,固相催化曝气氧化与生物抑制技术结合,在技术和经济可行性方面具有明显的优势。     

合水油田注水管线腐蚀成因与缓蚀措施

为解决合水油田庄六注注水管线严重腐蚀这一问题,通过对注水水质、挂片腐蚀形貌以及腐蚀产物组成、含量进行检测分析,查找原因,在此研究基础上开发了一种新型复配缓蚀剂,通过单因素试验和多指标正交试验设计对缓蚀剂MIQS、阻垢剂PAAS和杀菌剂MIT含量进行了优化。结果表明,溶解氧、侵蚀性CO2、Cl-过量引起的吸氧腐蚀、酸性腐蚀和点蚀是导致注水管线腐蚀的主要原因,Ca2+、细菌含量超标造成的结垢腐蚀和细菌腐蚀对其亦有一定影响;该复配缓蚀剂最佳配比为:115mg/L MIQS,30mg/L PAAS,55mg/L MIT,此条件下挂片缓蚀效果良好,腐蚀缓蚀率和点蚀缓蚀率高达99.57%和98.40%。     

壳聚糖及衍生物掺杂聚苯胺在0.5mol·L~(-1)HCl溶液中对碳钢的缓蚀性能

采用化学氧化法合成了壳聚糖掺杂聚苯胺(CTS-PANI)、羟丙基壳聚糖掺杂聚苯胺(HPCS-PANI)及羧甲基壳聚糖掺杂聚苯胺(CMC-PANI);利用红外光谱法(FTIR)对合成产物进行表征,用腐蚀试验和电化学测试研究了掺杂态聚苯胺对Q235钢在0.5mol·L~(-1) HCl溶液中的缓蚀性能。结果表明:本征态聚苯胺及掺杂态聚苯胺的缓蚀率随缓蚀剂含量的增加先增大后减小,当缓蚀剂的质量浓度达到50mg·L~(-1)时缓蚀率最大;四种缓蚀剂对Q235碳钢在0.5mol·L~(-1) HCl溶液中的缓蚀率从大到小顺序为CMC-PANIHPCS-PANICTS-PANIPANI,羧甲基壳聚糖掺杂聚苯胺的缓蚀性能最好,缓蚀率可达91.9%。     

油田产出水的腐蚀及防护研究

本文在对长庆油田的靖北、吴旗、油房庄和大水坑区块采油装置发生腐蚀原因分析的基础上,开展了产出水的缓蚀和杀菌试验研究。结果表明,引起井下管柱及集输管线腐蚀的因素主要有产出水矿化度高、H2S和SRB含量高、部分水质溶解氧超标以及井下存在CO2伴生气和不均匀结垢;优选的CI-2缓蚀剂具有较好的缓蚀效果,加量为50mg/L时,可使产出水的腐蚀速度由0.125mm/a降至0.012mm/a,缓蚀率达90%以上;经杀菌剂筛选,BI-2和BI-3对SRB、TGB具有较好的杀菌效果,为了防止产生抗药性,采用BI-2和BI-3交替加药。     

陕北气田气井腐蚀速率影响因素及规律

目的选择恰当、高效防腐对策以提高气田开发经济效益,保证气井安全生产。方法对陕北某气田的水质进行全面分析,并以通入饱和CO_2的气田气井产出水作为腐蚀介质,通过静态失重法探讨温度、矿化度、体系酸碱度、水介质中CO_2含量、H_2S含量、溶解氧含量、HCO3含量、Cl~-含量对设备管道腐蚀性的影响及其腐蚀规律。结果陕北某气田的气井产出水矿化度约为50 000 mg/L,且Cl~-、HCO3-含量偏高,水样呈弱酸性,p H值约6.5;腐蚀速率随水介质中CO_2含量、H_2S含量、溶解氧含量、HCO3-含量、Cl~-含量增加均呈增加趋势,在50℃时最大达到0.352 mm/a,p H值为7时最小为0.250 mm/a。结论陕北某气田设备管道的腐蚀主要表现为O_2腐蚀和CO_2腐蚀。     

陕北油田集输管线腐蚀原因分析及腐蚀防护技术研究

目的 通过分析陕北延长油田某联合站集输系统管线的腐蚀行为,找出该区块集输系统的腐蚀原因,进而提出控制腐蚀的有效方法.方法 基于灰关联分析理论,分析了集输系统采出液腐蚀的主要影响因素及其对管线设备腐蚀的影响程度.应用EDX能谱仪和DXS-500全自动三维成像显微镜,对集输管线内腐蚀产物和Q235钢进行表征.采用正交试验方法,合成适用于该集输管线的缓蚀剂,通过极化曲线和缓蚀性能评价对缓蚀剂进行定性和定量分析.结果 管线腐蚀的主要影响因素为pH值、S2?、SRB、CO2、Cl?等,能谱分析得出腐蚀产物主要组成有Fe、O、C、S元素.采用投加50 mg/L氧化性高效脱硫杀菌剂和50 mg/L缓蚀剂的措施后,挂片表面光滑且呈红色和黄色,坑的数量大幅度减少,坑的深度大幅度减小,最大腐蚀深度由80.937μm减少到16.25μm,腐蚀速率降低到0.0324 mm/a,缓蚀率达到90％以上.结论 Cl?破坏金属表面钝化膜、CO2和H2S协同作用共同影响着金属的腐蚀速率.采用氧化性高效脱硫杀菌剂配合所合成的缓蚀剂来控制腐蚀完全可行,可有效解决集输管线的腐蚀问题.     

一种HAP型高效缓蚀阻垢剂的研制及应用

目的通过对延长油田JX区块腐蚀结垢情况分析,针对性地研制并筛选缓蚀阻垢剂配方,获得阻垢、缓蚀效果最佳的HAP缓蚀阻垢剂。方法采用EDTA滴定法、称重法和腐蚀挂片分析技术,在温度为90℃时,对缓蚀阻垢剂的缓蚀效果和阻垢性能进行评价,通过反复对比分析,筛选配方,并进行了现场试验。结果与未添加缓蚀阻垢剂时相比,油井产出液分离水的腐蚀速率由0.125~0.161 mm/a下降到0.023~0.034 mm/a,缓蚀率达到了80%以上;混合结垢量由130~290 mg/L下降到7~15 mg/L,阻垢率达到了91%以上。结论应用EDTA滴定法、称重法和腐蚀挂片分析技术优选了缓蚀阻垢剂配方,在高温环境下,缓蚀阻垢剂综合性能优良,现场试验中的缓蚀阻垢效果显著。     

苏里格气田甲醇污水预处理中的防腐阻垢技术研究

针对苏里格气田某天然气处理厂的高浓度甲醇污水腐蚀现状,室内开发出,油田用除氧剂等。通过现场考察、室内试验及理论分析,对目前处理工艺流程增加除氧剂加药口,并将阻垢剂加药口从过滤器后换至反应沉降罐前,试验结果表明：该技术稳定性好,油田除氧剂现场加药量为0.1%,阻垢剂加药浓度为130mg/L,加药25天后过滤器出口腐蚀速率低至0.038mm/a,在75℃未出现结垢现象,解决了甲醇回收再利用设备的腐蚀和结垢问题,对整个系统起到很好的保护作用。     

CFD油田注水管线腐蚀分析及缓蚀剂评价

为了控制CFD油田注水管线腐蚀情况,通过水样及管线运行工况分析,研究了管线腐蚀主要影响因素,分析表明CFD油田注水管线腐蚀受温度、Cl-及水体流动影响较大。为缓解管线腐蚀,采用旋转挂片法考察了几种缓蚀剂的缓蚀效果。室内试验表明在90℃,0.3MPaCO2+3.0MPaN2,转速451转/分的条件下,缓蚀剂YFHC-093具有良好的缓蚀效果。现场试验结果表明缓蚀剂YFHC-093加注浓度在25mg·L-1时,可将注水管线腐蚀速率控制在0.0366mm·a-1以下,低于油田腐蚀标准。     

渤海某油田生产管线缓蚀剂筛选及性能评价

针对渤海某油田生产管线腐蚀情况,采用静态与旋转挂片法考察了几种缓蚀剂的缓蚀效果,室内试验表明,BHH-01C加药浓度为40 mg·L-1时,可将腐蚀速率控制在0.046mm·a-1以下,缓蚀效果良好。现场试验结果表明缓蚀剂BHH-01C加注浓度在20mg·L-1时,可将WHPA与WHPD平台生产管线腐蚀速率控制在0.00415mm·a-1及0.042 mm·a-1以下,低于油田腐蚀标准。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.