Comparative Coreflood Studies for Precipitation and Adsorption Squeeze with PPCA as the Scales Inhibitor

Comparative adsorption and precipitation squeezes carried out on field core materials demonstrate that significant lifetime enhancement is achievable for precipitation squeeze with respect to more conventional adsorption squeeze. Coreflood tests have been carried out under reservoir conditions (135°C) employing a poly-phosphinocarboxylate (PPCA) as the scales inhibitor. Field treatment simulations, carried out starting from coreflood data and considering the characteristics of a North Sea formation taken as the reference, confirmed the higher performance, in term of squeeze lifetime, of the precipitation squeeze with respect to adsorption. The results pointed out the importance of choosing the appropriate formulation once the operative conditions are known, in order to promote the inhibitor precipitation into the formation. Some implications of these results for the optimization of the precipitation squeeze technology for field applications, with particular emphasis to formation damage, are also discussed.     

Improvement of corrosion protection of steel by incorporation of a new phosphonated fatty acid in a phosphorus-containing polymer coating obtained by UV curing

Six formulations containing diacrylate monomers (from 89 to 92.5% (w/w)) as well as a phosphonated methacrylate monomer (from 1 to 10% (w/w)) were prepared. All formulations were UV-cured and the corrosion performance of the resulting coatings applied onto a steel substrate was assessed by electrochemical impedance spectroscopy (EIS). It was first shown that the coatings containing phosphonic acid methacrylate (MAPC1(OH)₂) instead of methacrylate phosphonic dimethyl ester (MAPC1) presented higher corrosion protection related to the strong adhesive properties of phosphonic acid on the metal substrate. A minimum MAPC1(OH)₂ content of 2.5% was determined to provide the highest impedance values (best efficiency). Then, a new bio-based compound, i.e. phosphonic acid-bearing oleic acid (phosphonated fatty acid), was synthesized and added as an inhibitor to the formulations. In the presence of this compound, the corrosion protection was notably improved. The beneficial effect of phosphonated fatty acid was explained by its inhibitive action at the steel/coating interface and by the improvement of the barrier properties.     

防垢剂BZF－2的研制与应用

桩西油田产出原油综合含水已达６０％－７０％，原用防垢剂ＨＥＤＰ已失去有效抑制集输站结垢的性能。本工作针对结垢最严重的桩５２站的应用，研制了以有机膦化合物和聚氧乙烯醚为主成份的防垢剂ＢＺＦ－２，在室内考察了不同条件下的防垢率、腐蚀性、配伍性等性能，在桩５２站进行了为期４个月的现场试验，加量为１０．３ｍｌ／ｌ、防垢率≥９８．０％，加药设备管线的腐蚀率大大降低。     

Synthesis and evaluation of the inhibitor effect of a new class of triazole compounds

In this work, a new class of triazole molecules, containing heteroatoms such as nitrogen and sulphur, is prepared. The effect of these molecules on the corrosion behaviour of iron was investigated. Electrochemical studies were performed in aerated chloride acid solution (1 M) by potentiodynamic polarisation curves. Surfaces were characterised by scanning electron microscopy.

The recorded electrochemical data showed that the corrosion resistance was greatly enhanced in the presence of inhibitor. The maximal protection efficiency exceeded 94%. The corrosion protection could be explained by the adsorption of inhibitor through the S- or N-atom and formation of a protective layer attached to the metal surface.     

植物型缓蚀剂的研制及应用

用直接浸泡--回流法从绿茶茶叶和米糠中提取了两种缓蚀剂TL和BR。利用失重法研究了缓蚀剂TL和BR浓度、介质酸度和腐蚀时间对碳钢的缓蚀作用的影响，以及TL、BR分别与六次甲基四胺(CN)复配后的缓蚀效果，并探讨了TL、BR的缓蚀机理。失重试验和极化曲线测试结果表明：缓蚀剂TL和BR对碳钢具有良好的缓蚀作用，属于阴极型缓蚀剂。     

硅钨杂多化合物的复配缓蚀剂及其缓蚀机理研究

通过旋转挂片试验,对硅钨杂多化合物的复配缓蚀剂进行了缓蚀性能的研究。结果表明：Ｎａ８［ＳｉＷ１１Ｏ３９］－ＺｎＣｌ２复配缓蚀剂具有良好的缓蚀性能,Ｎａ８［ＳｉＷ１１Ｏ３９］－ＺｎＣｌ２－葡萄糖酸钠复配缓蚀剂具有优良的缓蚀性能。通过极化曲线和光电子能谱初步探讨了缓蚀剂的作用机理。它们是阳极型缓蚀剂,Ｚｎ＾２＋的主要作用是在金属表面快速成膜,硅钨杂多化合物的作用不仅在金属表面,而且在次表面也起成膜作用     

Novel thiophene symmetrical Schiff base compounds as corrosion inhibitor for mild steel in acidic media

The inhibiting effect of two Schiff bases on the corrosion of the mild steel (MS) in 1 M HCl has been studied by electrochemical impedance spectroscopy (EIS) and Tafel polarisation measurements. The Schiff bases, 4,4′-bis(3-carboxaldehyde thiophene) diphenyl diimino ether (L₁) and 4,4′-bis(3-carboxaldehyde thiophene) diphenyl diimino ethane (L₂), were synthesized using 3-carboxaldehydethiophene and its corresponding amine. Polarisation curves reveal that both compounds are mixed type (cathodic/anodic) inhibitors and inhibition efficiency (% IE) increases with increasing concentration of compounds. It is suggested that their effects depend on their concentrations and the molecular structures. Adsorption of compounds on mild steel surface is spontaneous and obeys Langmuir’s isotherm.     

对叔丁基邻苯二酚的生产与应用

介绍了对叔丁基邻苯二酚的应用,简述目前国内采用的两种传统工艺生产方法,以及固本酸为催化剂的新工艺方法,相互比较,显而易见,新工艺法将是今后工业生产的发展方向。     

Bayesian uncertainty analysis with applications to turbulence modeling

In this paper, we apply Bayesian uncertainty quantification techniques to the processes of calibrating complex mathematical models and predicting quantities of interest (QoI's) with such models. These techniques also enable the systematic comparison of competing model classes. The processes of calibration and comparison constitute the building blocks of a larger validation process, the goal of which is to accept or reject a given mathematical model for the prediction of a particular QoI for a particular scenario. In this work, we take the first step in this process by applying the methodology to the analysis of the Spalart-Allmaras turbulence model in the context of incompressible, boundary layer flows. Three competing model classes based on the Spalart-Allmaras model are formulated, calibrated against experimental data, and used to issue a prediction with quantified uncertainty. The model classes are compared in terms of their posterior probabilities and their prediction of QoI's. The model posterior probability represents the relative plausibility of a model class given the data. Thus, it incorporates the model's ability to fit experimental observations. Alternatively, comparing models using the predicted QoI connects the process to the needs of decision makers that use the results of the model. We show that by using both the model plausibility and predicted QoI, one has the opportunity to reject some model classes after calibration, before subjecting the remaining classes to additional validation challenges.     

Electrochemical and optical microscopy study of red pepper seed oil corrosion inhibition by self-assembled monolayers (SAM) on 304 SS

Corrosion inhibition by red pepper seed oil (capsicol) on 304 stainless steel (SS) was studied in 1 M HCl solutions. The oil was extracted from the seed of the red pepper (Capsicum annuum L.), which was cultivated in East Java, Indonesia. Electrochemical and optical microscopy techniques were used to observe the performance of the corrosion-inhibition process. The inhibition efficiency reached 92.32% for an immersion time in capsicol of 30 min at room temperature and decreased with temperature. This inhibition behavior by capsicol was also justified by comparing the pictures of the samples with and without the inhibitor after corroding for one week.