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The present article provides an overview of the effect of hydrogen sulphide (H 2 S) on corrosion in polluted waters, including sea, river, brackish, geothermal and sewage waters. H 2 S is a weak, reducing acid which originates from sulphide minerals by natural acidification and/or from sulphurbearing, decaying organic matter by bacterial action. Human and industrial activities increase the generation of corrosive gases, dissolved in water: CO 2 , H 2 S and NH 3 . Carbon steel, stainless steel, aluminium alloys and copper base alloys are corroded by H 2 S, producing metallic, nonstable sulphide films. The H 2 S content in various waters, the electrode potential pH (Pourbaix) diagrams for Fe and Cu in H 2 S containing systems, and the electrochemical and corrosion performance of steel in oxygen depleted, H 2 S polluted waters, which indicate active corrosion behaviour, are presented and discussed.

The seas play an essential role for the peoples living on their coastal regions, since the marine infrastructure is located in the coasts. Seawater is a corrosive environment that affects infrastructure particularly in polluted seawater. Corrosion and pollution are pernicious chemical, physical processes that impair the quality of the environment and the durability of the marine structures and materials. They are aggravated by the discharge into the sea coast of municipal, industrial and agricultural effluents, which contain and produce toxic and highly corrosive components by biological and chemical degradation. Reinforced concrete and carbon steel are the main engineering materials used for the construction of marine installations and equipment but other metals and alloys: aluminium; copper, stainless steels are applied, too. Laboratory and field corrosion tests in seawater were carried out applying gravimetric, electrochemical and surface examination methods, based on American Society of Testing and Materials (ASTM) and National Association of Corrosion Engineers (NACE) standards. This work is the result of a cooperation between academic institutions in Mexico and Israel. The data generated advance the management of sea corrosion prevention and mitigation, and provide a guide for marine infrastructure maintenance and corrosion control. Several cases of corrosion in the sea coasts based on the authors experience and knowledge are presented.

Purpose -Aggressive environments that enhance indoor corrosion in industrial plants decrease the yielding of electronic equipment, causing electrical failures. The purpose of the present paper is to evaluate corrosion rates in metals used in electronic devices as a function of temperature, humidity and the concentrations of some air pollutants in order to predict the optimal conditions preventing or minimizing corrosion. Design/methodology/approach -Atmospheric pollutants mainly sulphur oxides, penetrating through small crevices and holes into electronic plants in combination with climatic factors such as humidity and heat, promote corrosion. The corrosion rate of the five most used metals in the electronics industry: carbon steel, copper, nickel, silver, and tin, were studied gravimetrically as a function of variations in humidity, temperature and air pollutant concentrations from 2003 to 2005. The samples were exposed in an instrumented boot to indoor conditions and gravimetric measurements were performed together with measurements of the above-mentioned parameters. Mathematical simulation applying Math Lab software was carried out as well. The ternary diagrams for pollutants, temperature and relative humidity were applied as a useful tool to correlate these parameters in indoor conditions with the corrosion rate of metals applied in the electronics industry. Findings -The obtained results have shown that the presence of even small concentrations of air pollutants promoted corrosion processes when time of wetness conditions were reached. Practical implications -The study was carried out in order to minimize the corrosion losses of the electronic plants situated especially in Mexicali City located on a semi-desert zone in the Northwest of Mexico. Originality/value -This paper establishes the relationship of variations of pollutants concentration, temperature and the relative humidity with the corrosion rate of metals in indoor conditions in the electronics industry located in the semi-arid zone of Mexicali. Design was characterized and simulated using the MathLab software.

Purpose -The aim of this work is to study the corrosion and scaling factors, mechanisms and processes affecting the materials, equipment and installations of the Cerro Prieto geothermal field (GTF). Design/methodology/approach -The physicochemical characteristics of the geothermal well and fluids were analysed, recorded and related to the corrosion and scaling phenomena. Findings -The high temperature and salinity of the steam-brine mixture and the presence of hydrogen sulphide and carbon dioxide impart a severe level of corrosivity. Originality/value -Corrosion and scaling control assure an efficient production regime, provide for the durability of the GTF engineering materials and equipment and contribute to environmental quality.

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Other critical problems, that impact on infrastructure and industry are climate change, global warming and greenhouse emissions, all interrelated phenomena.This chapter presents important aspects of corrosion in industrial infrastructure, its causes, impacts, control, protection and prevention methods. Materials in industryMetallic materials play a key role in the development of a country and its sustained growth in the context of the global economy. Table 1 shows a classification and the properties of dif-