含硫污水系统耐蚀材料的筛选与应用

针对西北地区一综合炼油厂含硫污水管线的严重腐蚀问题，分析了腐蚀原因，确立了材料筛选方案，通过实验室静态挂片试验绘制了重量损失率变化曲线和现场挂片等试验手段，筛选推荐出了树脂玻璃钢耐蚀材料。工业生产应用结果表明，MFE-2型树脂玻璃钢是适用于该厂含硫污水系统的耐蚀材料，为类似装置的长周期运行提供了借鉴和经验。     

Investigation on the changes effected by tool profile on mechanical and tribological properties of friction stir processed AZ31B magnesium alloy

The present study investigates the effect of tool shoulder profile on the mechanical and tribological properties of friction stir processed AZ31B magnesium alloy. The tool rotational speed and feed rate are the chosen process parameters. The experiments were conducted with 3 level 2 factors full factorial design. The recorded responses were tensile strength, wear losses and corrosion rate. The results were analyzed with the help microstructures of the processed samples. The study reveals that, for concave shoulder tool, the strain hardening effect was playing a major role in determining the properties of the processed materials and for the step shoulder tool, the grain size plays a major role in determining the properties of the processed materials.     

Application of Forensic Techniques for Age Dating and Source Identification in Environmental Litigation

A multitude of forensic techniques are available for age dating and source identification, including corrosion models for underground storage tanks, the commercial availability of a compound, chemical associations with discrete types of manufacturing processes, chemical profiling, proprietary additives, stable isotope analysis, degradation models, biomarkers and contaminant transport models. The selection and use of these techniques in environmental litigation must be thoroughly understood and applied to be effective as forensic evidence. When introduced as scientific evidence, the governing assumptions and quality of the data are critically evaluated and frequently successfully challenged. The purpose of this paper is to present an overview of commonly used environmental forensic techniques and their possible applications so that a user can decide which technique or combination of methods is most appropriate for their case.     

小麦在与水杨酸诱导的应答过程中PGIP的积累

以ＳＷ８９－２５８９小麦品系为材料，利用自制的小麦抗ＰＧＩＰ血清和ｄｏｔ－ｉｍｍｕｎｏｂｉｎｄｉｎｇ ａｓｓａｙ，并结合ＰＧＩＰ粗提液对ｅｎｄｏ－ＰＧ的抑制实验，研究了小麦内源多聚半乳糖醛酸酶抑制蛋白（ＰＧＩＰ）水平与水杨酸之间的应答关系。发现用水杨酸处理过的ＰＧＩＰ粗提液在ＮＣ膜上的显色斑点颜色均较Ｈ２Ｏ处理的ＰＧＩＰ粗提液深，而且对ｅｎ－ｄｏ－ＰＧ的抑制程度也高于未用水杨酸处理的ＰＧＩＰ粗提液     

Discussion of Chicgoua Noubactep on “Removal of thiobencarb in aqueous solution by zero valent iron” by Md. Nurul Amin et al. [Chemosphere 70 (3) (2008) 511–515]

The following comments are proposed to clarify some related issues on the use of zero valent iron micrometric particles for the treatment of a thiobencarb pesticide solution published in a recent article by Nurul Amin et al., [Nurul Amin Md., Kaneco, S., Kato, T., Katsumata, H., Susuki, T., Otha, K., 2008. Removal of thiobencarb in aqueous solution by zero valent iron. Chemosphere 70 (3), 511–515], and discussed later by Chicgoua Noubactep.     

Terrestrial exposure of oilfield flowline additives diminish soil structural stability and remediative microbial function

Onshore oil production pipelines are major installations in the petroleum industry, stretching many thousands of kilometres worldwide which also contain flowline additives. The current study focuses on the effect of the flowline additives on soil physico-chemical and biological properties and quantified the impact using resilience and resistance indices. Our findings are the first to highlight deleterious effect of flowline additives by altering some fundamental soil properties, including a complete loss of structural integrity of the impacted soil and a reduced capacity to degrade hydrocarbons mainly due to: (i) phosphonate salts (in scale inhibitor) prevented accumulation of scale in pipelines but also disrupted soil physical structure; (ii) glutaraldehyde (in biocides) which repressed microbial activity in the pipeline and reduced hydrocarbon degradation in soil upon environmental exposure; (iii) the combinatory effects of these two chemicals synergistically caused severe soil structural collapse and disruption of microbial degradation of petroleum hydrocarbons.     

Desorption of arsenic from drinking water distribution system solids

Previous work has shown that arsenic can accumulate in drinking water distribution system (DWDS) solids (Lytle et~al., 2004) when arsenic is present in the water. The release of arsenic back into the water through particulate transport and/or chemical release (e.g. desorption, dissolution) could result in elevated arsenic levels at the consumers' tap. The primary objective of this work was to examine the impact of pH and orthophosphate on the chemical release (i.e. desorption) of arsenic from nine DWDS solids collected from utilities located in the Midwest. Arsenic release comparisons were based on the examination of arsenic and other water quality parameters in leach water after contact with the solids over the course of 168~hours. Results showed that arsenic was released from solids and suggested that arsenic release was a result of desorption rather than dissolution. Arsenic release generally increased with increasing initial arsenic concentration in the solid and increasing pH levels (in the test range of 7 to 9). Finally, orthophosphate (3 and 5 mg PO₄/L) increased arsenic release at all pH values examined. Based on the study results, utilities with measurable levels of arsenic present in their water should be aware that some water quality changes can cause arsenic release in the DWDS potentially resulting in elevated levels at the consumer's tap.     

Corrosion failure probability analysis of buried gas pipelines based on subset simulation

Corrosion is the main reason for the failure of buried gas pipelines. For effective corrosion failure probability analysis, the structural reliability theory was adopted in this study to establish two calculation models for pipeline corrosion failure: the pressure failure model and von Mises stress failure model. Then, two calculation models for the corrosion failure probability were established based on a corrosion depth growth model obtained from actual survey data of soil corrosion characteristics. In an example, Monte Carlo simulation (MCS) and subset simulation (SS) were used to analyze the corrosion failure probability of pipelines, and the results were compared. SS can compensate for the shortcomings of MCS as it has higher computational efficiency and accuracy. Therefore, SS was adopted to simulate variations in the corrosion failure probability of buried pipelines with the service time for the two failure probability calculation models, which were applied to a natural gas pipeline located in a chemical industry park in Zhuhai, China. A sensitivity analysis was carried out on the relevant parameters that affect the failure probability. The results showed that multiple loads caused by the covering soil, residual stress, temperature differential, and bending stress have a non-negligible effect on the pipeline reliability. The corrosion coefficients gradually become the most important factors that affect the failure probability with increased service time. The proposed methodology considers the actual operating conditions of pipelines to provide a reliable theoretical basis for integrity management.     

尿素合成塔内衬腐蚀规律研究

本文归纳总结了水溶液全循环工艺尿素合成塔内衬腐蚀规律。研究表明使用超过13年的尿素合成塔内衬均匀腐蚀规律开始分化,个别塔内衬腐蚀加剧明显;而且尿素合成塔中偏上部筒节一般为剩余壁厚最薄的筒节,可通过适当调节该筒节塔盘间距或塔板筛孔数,减少该处局部反应时间,改善温度分布,延长整塔使用寿命。另外,多塔并联使用时,应注意管道分压导致各塔氧含量不均引发的不均匀腐蚀。     

A methodology for identifying and addressing dead-legs and corrosion issues in a Process Hazard Analysis (PHA)

Identifying dead-legs and related corrosion issues continues to be a challenge in the process industry. Pipeline corrosion has been a factor in several recent incidents involving releases and fires. A review of incident reports and citations over the past ten years indicates that Process Hazard Analysis (PHA) revalidations have been noted for not addressing the hazards of a process including corrosion mechanisms and dead-legs. In order for the hazards to be addressed, they must first be accurately identified in a PHA and documented along with any recommended actions for preventive maintenance. This paper describes a methodology for identifying and addressing dead-legs and related corrosion issues in a PHA that can be used to update corporate PHA procedures to be more robust in preventing corrosion related incidents.