Discussion of Oxygen Threshold Level for Corrosion Management in Seawater Injection Systems

2021 ◽  
Author(s):  
Jean Vicente Ferrari
Keyword(s):  
Corrosion Rate ◽  
Oxygen Reduction ◽  
Water Injection ◽  
Steel Corrosion ◽  
Threshold Level ◽  
International Standards ◽  
Limiting Current ◽  
Order Of Magnitude ◽  
The Impact ◽  
Oxygen Concentrations

Abstract Generally, in water injection systems, oxygen levels starting from around eight ppm are deoxygenated to below 50 ppm, following international standards' guidelines. This work aims to discuss the impact of such a magnitude value of oxygen contamination on steel corrosion in seawater injection systems by analysing theoretical polarisation curves and results from published works with different approaches. Corrosion models consider mass-transfer controlled diffusion of oxygen to predict the maximum steel corrosion rate, which depends on the oxygen limiting current, which in turn is strongly influenced by flow velocity. The effect of free chlorine on corrosion in seawater injection systems has also been considered and included in an oxygen equivalent parameter. In such systems, where oxygen reduction is the key cathodic reaction, the corrosion process may be under cathodic activation control, independent of flow at higher velocities or when erosion-corrosion begins. In this work, theoretical polarisation curves were constructed by using published oxygen and chlorine cathodic limiting currents (iLc) on carbon steel and a noble metal electrode, respectively. Aerated (200 ppb and 9000 ppb of oxygen) and deaerated conditions (50 ppb of oxygen) and the presence of 300 ppb of chlorine were applied to the assumed exchange current densities (io). Neutral (pH 7) and acid (pH 4) conditions (considering the presence of CO2) were also assumed to be at room temperature and pressure. Since the corrosion rate in lower oxygen concentrations (ppb order of magnitude) may result in corrosion rates of the same order of magnitude than in higher oxygen concentrations (ppm order of magnitude) when comparing and analysing results from experimental, semi-empirical or mechanistic approaches, it is necessary to weigh up the effects of both steel surface (bare or scaled/corrosion products) and flow. At oxygen concentrations below 200 ppb and under acid conditions, the contribution of H+ reduction on corrosion rate starts to be higher than oxygen reduction, mainly in the absence of chlorine.

Test and Study on Impact of Corrosion on Bond Force between Steel and Concrete

2010 ◽  
Vol 36 ◽  
pp. 176-181
Author(s):  
Xian Feng He ◽  
Shou Gang Zhao ◽  
Yuan Bao Leng
Keyword(s):  
Reinforced Concrete ◽  
Corrosion Rate ◽  
Concrete Structure ◽  
Steel Corrosion ◽  
Reinforced Concrete Structure ◽  
Bond Force ◽  
Steel Bars ◽  
Protection Layer ◽  
Corrosion Of Steel ◽  
The Impact

The corrosion of steel will have a bad impact on the safety of reinforced concrete structure. In severe cases, it may even be disastrous. In order to understand the impact of steel corrosion on the structure, tests are carried out to study corrosion and expansion rules of steel bars as well as the impact rules of corrosion on bond force between steel and concrete. The results show that wet and salty environment will result in steel corrosion; relatively minor corrosion will not cause expansion cracks of protection layers; when steel rust to a certain extent, it will cause cracks along the protection layer; when there exists minor corrosion in steel and the protection layer does not have expansion cracks, the bond force is still large and rapidly decreases as the corrosion rate increases.

Assessment of the steel corrosion rate at the infrastructure facilities of hydrocarbon deposits as a function of the mineralization and temperature

2021 ◽  
Vol 87 (6) ◽  
pp. 41-44
Author(s):  
R. K. Vagapov ◽  
A. Yu. Prokopenko ◽  
I. S. Tomsky
Keyword(s):  
Corrosion Rate ◽  
Steel Corrosion ◽  
Gas Production ◽  
Safety And Reliability ◽  
Equipment And Pipelines ◽  
Gas Fields ◽  
High Degree ◽  
The Impact ◽  
Hydrocarbon Deposits ◽  
Oil Gas

Active and promising hydrocarbon deposits, including those on the sea shelf, are often characterized by an increased content of corrosive carbon dioxide and hydrogen sulfide. Corrosive gases present in the produced crude is a serious threat to the safety and reliability of the equipment and pipelines operating at gas production facilities. We present the results of assessing the dependence of the steel corrosion rate in the presence of CO2 on the salinity and temperature. The experimental data were processed using the methods of mathematical statistics. It is shown that the obtained dependences provide calculation of the corrosion rate with a high degree of reliability. The impact of each factor (salinity and temperature) on the steel corrosion rate was evaluated separately. The results obtained can be used to control and predict the danger of corrosion destruction of the infrastructure facilities of oil – gas fields.

Research of atmospheric corrosion activity on oil pumping stations with tank farms

2021 ◽  
pp. 88-92
Author(s):  
Павел Олегович Ревин ◽  
Алексей Витальевич Макаренко ◽  
Андрей Алексеевич Губенков ◽  
Ирина Олеговна Осина
Keyword(s):  
Corrosion Rate ◽  
Atmospheric Corrosion ◽  
Gravimetric Method ◽  
Steel Corrosion ◽  
Steel Structure ◽  
Climatic Conditions ◽  
International Standards ◽  
Corrosion Activity ◽  
Climatic Regions ◽  
Pumping Stations

В настоящее время в отечественных национальных и международных стандартах отсутствуют данные по коррозионной активности атмосферы регионов, в которых расположены нефтеперекачивающие станции с резервуарными парками, эксплуатируемые российским оператором магистральных нефте- и нефтепродуктопроводов. В нормативных документах ПАО «Транснефть», регламентирующих требования к антикоррозионным покрытиям для наружной поверхности резервуаров, определены три категории коррозионной активности атмосферы по ISO 12944-2:2017. Данная классификация учитывает климатические условия регионов, но не учитывает скорость коррозии стали. В этой связи с целью определения скорости коррозии стальных конструкций в различных климатических районах, где расположены объекты организаций системы «Транснефть», была проведена серия испытаний. На 28 НПС в восьми климатических районах были установлены стенды с образцами из стали 09Г2С. Скорость коррозии металла образцов определяли гравиметрическим методом после выдержки в течение шести месяцев, одного года, двух, трех, четырех и пяти лет. Установлено, что скорость коррозии металлических образцов составила от 55 до 236 г/(м∙год), что соответствует категории коррозионной активности атмосферы С2 и С3 по ISO 12944-2:2017 и ГОСТ 34667.2-2020. Наибольшая скорость коррозии - от 177 до 236 г/(м∙год) - наблюдалась в районах расположения НПС в непосредственной близости от моря (до 1,5 км от береговой линии). Currently, there is no data included in the state and international standards on the corrosion activity of the atmosphere in the regions in which oil pumping stations with tank farms are situated, which are operated by Russian main oil and oil products pipeline operators. In the regulatory documents of Transneft PJSC, which specify the requirement for anticorrosion coatings for the outer surfaces of tanks, three categories of atmospheric corrosion activity are defined as per ISO 12944-2:2017. This classification takes into account the climatic conditions of the regions, but not the steel corrosion rate. In this regard, in order to determine the corrosion rate of steel structure in various climatic regions, where Transneft facilities are situated, a series of tests was performed. The test bench with 09G2S steel samples was installed on 28 oil pumping stations in eight climatic regions. The corrosion rate of the metal samples was determined by the gravimetric method after tempering within the period of six months, one year, two, three, four and five years. It has been established that the corrosion rate of the metal samples amounted from 55 to 236 g/(m·per year), which corresponds to the atmospheric corrosion activity category C2 and C3 as per ISO 12944-2:2017 and GOST 34667.2-2020. The highest corrosion rate, from 177 to 236 g/(m·per year) - was observed in the OPS location regions with close proximity to sea (1,5 km to shore line).

IFRS IMPLEMENTATION AS ONE OF THE FACTORS FOR IMPROVING THE INVESTMENT CLIMATE IN UKRAINE

2017 ◽  
Author(s):  
Kateryna Sova ◽  
◽  
Natalia Yatsenko ◽  
Denys Zagirniak ◽  
◽  
...  
Keyword(s):  
Financial Reporting ◽  
Direct Investment ◽  
Financial Statements ◽  
International Standards ◽  
Investment Climate ◽  
The European Union ◽  
Economic Activities ◽  
Financial Reporting Standards ◽  
Almost All ◽  
The Impact

The article is devoted to the study of the impact of the introduction of International Financial Reporting Standards (IFRS) on changes in the investment climate in Ukraine. The relevance of the topic is that improving the practice of applying IFRS as a tool for exchanging financial information is one of the key conditions for improving the investment climate in Ukraine. The authors have created the generalized scheme that illustrates the chronological list of enterprises that are required by law to prepare financial statements in accordance with IFRS. It was noted that in 2018, in accordance with Part 2 of Article 12 of the law on accounting and financial reporting in Ukraine and resolution of the Cabinet of Ministers of Ukraine No. 547 from 11.07.2018, the criteria of enterprises that are required to prepare financial statements in accordance with IFRS were updated. This step significantly increased the level of application of international standards due to the adoption of such a decision at the legislative level. The dynamics of the number of IFRS enterprises in Ukraine was analyzed. The analysis showed that over the past three years, the number of almost all enterprises that must apply international standards has been growing. The advantages of using IFRS for different users of financial statements were determined. It was determined that the priority users of IFRS financial statements are investors. At the same time, it was noted that the main advantage for other users of financial statements prepared in accordance with international standards is the improvement of the investment climate. The dynamics of the Investment Attractiveness Index of Ukraine based on the Likert scale in the period from 2016 to 2020 was analyzed. The direct investment receipts to Ukraine from the European Union countries were studied. The dynamics of direct investment in the Ukrainian economy was analyzed for two types of economic activities that should form financial statements in accordance with IFRS, namely, the extractive industry and quarrying, as well as financial and insurance activities.

Alteraciones sistémicas y metabólicas producidas por lesión medular

2019 ◽  
Vol 1 (1) ◽  
pp. 59-75
Author(s):  
Gabriel Guízar Sahagún
Keyword(s):  
Spinal Cord ◽  
Daily Living ◽  
Autonomic Function ◽  
Clinical Presentation ◽  
Scientific Literature ◽  
International Standards ◽  
Therapeutic Approaches ◽  
Cord Injury ◽  
Life Threatening ◽  
The Impact

Besides the well-known loss of motor and sensory capabilities, people with spinal cord injury (SCI) experience a broad range of systemic and metabolic abnormalities including, among others, dysfunction of cardiovascular, respiratory, gastrointestinal, urinary, and endocrine systems. These alterations are a significant challenge for patients with SCI because such disorders severely interfere with their daily living and can be potentially life-threatening. Most of these disorders are associated with impairment of regulation of the autonomic nervous system, arising from disruption of connections between higher brain centers and the spinal cord caudal to the injured zone. Thus, the higher and more complete the lesion, the greater the autonomic dysfunction and the severity of complications.This article summarizes the medical scientific literature on key systemic and metabolic alterations derived of SCI. It provides information primarily focused on the pathophysiology and clinical presentation of these disorders, as well as some guides to prevent and alleviate such complications. Due to the impact of these alterations, this topic must be a priority and diffuse to those involved with the care of people with SCI, including the patient himself/herself. We consider that any collaborative effort should be supported, like the development of international standards, to evaluate autonomic function after SCI, as well as the development of novel therapeutic approaches.

Pound Wise and Penny Foolish? Weight Loss and The Dynamics of Health Care Spending

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Thomas G Koch
Keyword(s):  
Weight Loss ◽  
Cost Savings ◽  
Cost Effective ◽  
Economic Consequences ◽  
Health Care Spending ◽  
Order Of Magnitude ◽  
Dynamic Measures ◽  
The Cost ◽  
The Impact ◽  
The Relationship

Current estimates of obesity costs ignore the impact of future weight loss and gain, and may either over or underestimate economic consequences of weight loss. In light of this, I construct static and dynamic measures of medical costs associated with body mass index (BMI), to be balanced against the cost of one-time interventions. This study finds that ignoring the implications of weight loss and gain over time overstates the medical-cost savings of such interventions by an order of magnitude. When the relationship between spending and age is allowed to vary, weight-loss attempts appear to be cost-effective starting and ending with middle age. Some interventions recently proven to decrease weight may also be cost-effective.

scholarly journals Caribbean Consortium for Research in Environmental and Occupational Health (CCREOH) Cohort Study: influences of complex environmental exposures on maternal and child health in Suriname

BMJ Open ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. e034702
Author(s):  
Wilco Zijlmans ◽  
Jeffrey Wickliffe ◽  
Ashna Hindori-Mohangoo ◽  
Sigrid MacDonald-Ottevanger ◽  
Paul Ouboter ◽  
...  
Keyword(s):  
Cohort Study ◽  
Occupational Health ◽  
Pregnant Women ◽  
Fish Consumption ◽  
Depression Scale ◽  
Environmental Exposures ◽  
International Standards ◽  
Long Term Effects ◽  
The Impact ◽  
Environmental And Occupational Health

PurposeThe Caribbean Consortium for Research in Environmental and Occupational Health prospective environmental epidemiologic cohort study addresses the impact of chemical and non-chemical environmental exposures on mother/child dyads in Suriname. The study determines associations between levels of environmental elements and toxicants in pregnant women, and birth outcomes and neurodevelopment in their children.ParticipantsPregnant women (N=1143) were enrolled from December 2016 to July 2019 from three regions of Suriname: Paramaribo (N=738), Nickerie (N=204) and the tropical rainforest interior (N=201). Infants (N=992) were enrolled at birth. Follow-up will take place until children are 48 months old.Findings to dateBiospecimens and questionnaire data on physiological and psychosocial health in pregnant women have been analysed. 39.1% had hair mercury (Hg) levels exceeding values considered safe by international standards. Median hair Hg concentrations in women from Paramaribo (N=522) were 0.64 µg/g hair (IQRs 0.36–1.09; range 0.00–7.12), from Nickerie (N=176) 0.73 µg/g (IQR 0.45–1.05; range 0.00–5.79) and the interior (N=178) 3.48 µg/g (IQR 1.92–7.39; range 0.38–18.20). 96.1% of women ate fish, respective consumption of the three most consumed carnivorous species, Hoplias aimara, Serrasalmus rhombeus and Cichla ocellaris, known to have high Hg levels, was 44.4%, 19.3% and 26.3%, respectively, and was greater among the interior subcohort. 89% frequently consumed the vegetable tannia, samples of which showed presence of worldwide banned pesticides. 24.9% of pregnant women had Edinburgh Depression Scale scores indicative of probable depression.Future plansFish consumption advisories are in development, especially relevant to interior women for whom fish consumption is likely to be the primary source of Hg exposure. Effects of potentially beneficial neuroprotective factors in fish that may counter neurotoxic effects of Hg are being examined. A pesticide literacy assessment in pregnant women is in progress. Neurodevelopmental assessments and telomere length measurements of the children to evaluate long-term effects of prenatal exposures to toxicant mixtures are ongoing.

scholarly journals Investigation of Corrosion Rate and Rust Expansion Form of Segment Reinforcement for Shield Tunnel by Combined Action of Soil Loading, Chloride Ion and Stray Current

2021 ◽  
Vol 13 (6) ◽  
pp. 3444
Author(s):  
Zheng Li ◽  
Hao Jin ◽  
Shuo Yu
Keyword(s):  
Corrosion Rate ◽  
Steel Corrosion ◽  
Chloride Ion ◽  
Shield Tunnel ◽  
Uniform Corrosion ◽  
Stray Current ◽  
Soil Loading ◽  
Capacity Degradation ◽  
Expansion Form ◽  
Combined Action

Segment reinforcement corrosion can cause bearing-capacity degradation of shield tunnel, which is unsafe for the metro operation. Therefore, a three-dimensional computational model was proposed in this paper to study the corrosion rate and rust expansion form of segment reinforcement by the combined action of soil loading, chloride ion and stray current. The results show that the arch waist segment steel corrosion rate in the middle is larger than the ends. The rust expansion form of segment reinforcement appears be an eccentric circle. The radius size and circular center are related to the non-uniform corrosion coefficient and the maximum corrosion current density.

scholarly journals Ice Coverage Induced by Depositing a Water Drop onto the Supercooled Substrate at Extreme Low Vapor Pressure

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 691
Author(s):  
Yugang Zhao ◽  
Zichao Zuo ◽  
Haibo Tang ◽  
Xin Zhang
Keyword(s):  
Vapor Pressure ◽  
Substrate Temperature ◽  
Water Drop ◽  
Industrial Processes ◽  
Aircraft Icing ◽  
Ice Coverage ◽  
Fundamental Understanding ◽  
Order Of Magnitude ◽  
The Impact ◽  
Kinetics Of

Icing/snowing/frosting is ubiquitous in nature and industrial processes, and the accretion of ice mostly leads to catastrophic consequences. The existing understanding of icing is still limited, particularly for aircraft icing, where direct observation of the freezing dynamics is inaccessible. In this work, we investigate experimentally the impact and freezing of a water drop onto the supercooled substrate at extremely low vapor pressure, to mimic an aircraft passing through clouds at a relatively high altitude, engendering icing upon collisions with pendant drops. Special attention is focused on the ice coverage induced by an impinging drop, from the perimeter pointing outward along the radial direction. We observed two freezing regimes: (I) spread-recoil-freeze at the substrate temperature of Ts = −15.4 ± 0.2 °C and (II) spread (incomplete)-freeze at the substrate temperature of Ts = −22.1 ± 0.2 °C. The ice coverage is approximately one order of magnitude larger than the frozen drop itself, and counterintuitively, larger supercooling yields smaller ice coverage in the range of interest. We attribute the variation of ice coverage to the kinetics of vapor diffusion in the two regimes. This fundamental understanding benefits the design of new anti-icing technologies for aircraft.

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