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The purpose of this paper is to assess the serious corrosion problems of the water injection system on the offshore oil field and to study the type, and effect factors and mechanisms of corrosion on the offshore oil field in order to develop an effective corrosion inhibitor for the sea water injection system.

The corrosion of metal in a water injection system was studied by weight‐loss and electrochemical methods.The effect factors and mechanisms of corrosion on the offshore oil field were proposed from the trend of corrosion.

FeCO₃ is the main corrosion product in the water injection system of the Chengdao Offshore Oil Field. The corrosion rate of coupons in sea water injection systems reaches a maximum peak at a temperature of 50‐60°C. The corrosion rate of coupons exposed in all three water samples increased with an increase in the dissolved oxygen concentration. When the mixed ratio of sea water and produced water and well water is 1:3:1 or 1:2:2, the corrosion rate of carbon steel is lower than is the case in pure water. The electrochemical mechanism of corrosion indicates that corrosion in the well water, produced water, and sea water samples were all controlled by the oxygen absorption process, which controlled the cathodic reaction. The corrosion rate of coupons followed the ranking order: well water; produced water; sea water.

This paper provides the main corrosion product in the water injection system of the Chengdao Offshore Oil Field, and provides new information on the effect factors and mechanisms of corrosion on the offshore oil field.

The hydrologic losses due to net evaporation in the Aral Sea have interesting analogs in the interior-drainage basins of the American West. Each of the three places discussed here – the Salton Sea, Owens Lake, and Mono Lake – has its own unique historical and geographic circumstances, but the story of each place has certain parallels to the Aral Sea disaster. Each place experienced dramatic water losses during much of the 20th century, but the emergence of environmental science and law in recent decades has caused significant policy changes. The Salton Sea is still declining, and modest efforts by state and federal agencies to halt the decline are inadequate. A proposal to build dikes to save part of the water body and convert the rest to salt evaporation ponds cited the Aral Sea as a model for the Salton Sea's future. The dry Owens Lake bed yields windblown dust that exceeds the Clean Air standard for fine particulate matter (PM 10), so Los Angeles is now required to release additional water back into the basin to create more shallow wetlands. In Mono Lake, a negotiated settlement has reversed the water loss while protecting vital interests of all parties, and a substantial ecological restoration plan is being implemented. The history of the American analogs to the Aral Sea, especially the success story of Mono Lake, may indicate potential pathways to progress in reducing problems caused by large-scale water diversion.

In this chapter, the title theme of “Disaster by Design” is explored and justified. Even from early times, the Aral Region was subject to alterations of natural conditions due to human intervention, often deliberate and designed. After the final conquest by Russia, the region became a fixed colony as part of the Soviet Union, ripe for exploitation characteristic of the Soviet approach to nature broadly and to stigmatized areas specifically. The Aral region was selected for irrigated cotton and other cultivation even though the consequences for desiccation of the sea, desertification, and salinization were understood. The decision was so calculated that even a cost–benefit analysis was offered to show that the Aral fishery was worth but a fraction of the cotton potential. The destruction of the region was made possible by a Soviet system of central planning and peripheral control. The brief glimmer of hope for the region evidenced during glasnost was the only moment where the Aral's fate was not sealed. The outcome is a model of ecological disaster by design, an environmental injustice, and an indication of the abusive nature of authoritarian power.

An investigation of the behaviour of a soluble resin coating on a steel substrate was carried out by open circuit potential and electrochemical techniques. Exposure conditions were with artificial sea‐water and natural sea‐water. The anticorrosion properties of the soluble resin material and its protection of the steel panel from marine corrosion were estimated by comparison with the untreated steel. The weight effect of the film coating and the temperature of the media were also studied.

Central Asian nations all gained their independence from the former Soviet Union in 1991. Unfortunately, with their independence, they also inherited many environmental problems. By far, the most pervasive issue is the shrinking of the Aral Sea. The enormity of the environmental crisis of the Aral Sea has been attested by environmentalists both in Central Asia and in other parts of the world. In this chapter, the broad scope of the disaster is set forth along with its principle causes. An overview of the geography and water supply in the region is given. And the daunting challenge of cross boundary impact and thus need for multinational cooperation is discussed. The challenge in the region today is twofold. First, it must address the Aral Sea disaster. And second, it must create the conditions to sustainably manage transboundary water resources to head off new catastrophe.

The corrosion behaviour of lead and its alloys in sea‐water is of great commercial interest in view of the considerable use of submerged telecommunications cables and the growing use of lead anodes for cathodic protection of marine structures. This article is concerned with the corrosion of lead in sea‐water and saline solutions and with the anodic behaviour of lead in chloride solutions.

This paper aims to study the influence of load and environment medium on the fretting behavior of SAF 2507 SDSS.

In this study, the effect of load on the fretting behavior of SAF 2507 SDSS in air and sea water were studied. The fretting wear tests under different loads were conducted with a ball-on-flat contact configuration. The friction coefficient, wear volume, surface morphology and oxidation component were determined.

With the increase of applied load, the friction coefficient decreases both in air and sea water. The fretting mechanism is gradually transformed from partial slip regime to slip regime in air while the fretting counterparts are all in the state of gross slip in sea water. In sea water, the friction coefficient is lower while the wear loss is higher compared with that in air.

This research suggests that the fretting behavior of SAF 2507 SDSS is related to load and environment medium.

The results may help us to choose the appropriate load under different environments.

The main originality of the research is to reveal the fretting behavior of SAF 2507 SDSS under different loads in air and sea water, which would help us to realize fretting behavior of SAF 2507 SDSS is controlled by the combination of applied load and lubricating environment.

The peer review history for this article is available at: http://dx.doi.org/10.1108/ILT-08-2019-0335.

The basic aspects and mechanism of corrosion of steel piles in sea water are briefly discussed. The effects of parameters viz. pH, salinity, dissolved oxygen, temperature and wind velocity responsible for the corrosion of steel piles have been presented. The methods used for corrosion control and the impressed current cathodic protection technique in particular, with its merits, when applied to under‐water marine structures are outlined. The values and importance of potential required at the surface under protection, surface current density requirement and its distribution for the protection of steel structures under different service conditions useful for the design of cathodic protection systems are presented. The characteristics of various types of anode materials with a special reference to the latest platinized (Platinum‐Niobium) niobium anodes, with their merits, over other types of anodes are tabulated. The basic considerations required for the design of cathodic protection and the design of the system have been presented.

Introduction Although nickel is generally regarded as a corrosion resistant material its resistance to sea water is only moderate. In fast flowing sea water its corrosion rate is very low; of the order of 0.0005 in/yr. Under stagnant conditions, however, it is susceptible to pitting and crevice corrosion attack. Consequently, alloying has been a common method of improving corrosion resistance to obtain a material having the excellent resistance of nickel to fast flowing sea water together with an improved resistance to pitting corrosion.

Marine corrosion is one of those generic titles that many understand but very few can define. Basically it is corrosion due to sea‐water but, in fact, the worse corrosion is experienced when the sea‐water is present in the form of a mist. Any consideration of marine corrosion must, in consequence, be based on the corrosivity of sea‐water, sea‐water‐laden atmospheres, and mixtures of these.