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An effective chemical conditioning technique was successfully tested and investigated to control and minimize the chemistry-related damages within mixed metallurgy steam and water cycle of Heller dry cooled combined cycle power plants (CCPPs), in which cooling water and condensate are completely mixed in direct contact condenser. This study aims to perform a comprehensive experimental research in four mixed metallurgy steam and water cycle.

A comprehensive experimental study was carried out in four mixed metallurgy steam and water cycle fabricated with ferrous- and aluminum-based alloys which have various corrosion resistance capabilities in contact with water. Chemical conditioning was conducted using both volatile and non-volatile alkalizing agents, and, to perform chemical conditioning effectively, quality parameters (pH, conductivity, dissolved oxygen, sodium, silica, iron, aluminum and phosphate) were monitored by analyzing grab and online samples taken at eight key sampling points.

Results indicated that pH was the most critical parameter which was not mainly within the recommended ranges of widely used standards and guidelines at all key sampling points that generally increases the occurrence of chemistry-related damages. The other quality parameters were mostly satisfactory.

In this research, the development of a suitable chemical conditioning technique in mixed metallurgy steam and water cycle, fabricated with ferrous and aluminum-based alloys, was studied. The obtained results in this thorough research work was evaluated by comparison with the chemistry limits of the widely used standards and guidelines, and combined use of volatile and solid alkalizing agents was considered as a promising chemical conditioning technique for utilization in mixed metallurgy units of Heller dry cooled CCPPs.

The purpose of this paper is to research the morphologies of the oxide films formed on the internal surfaces of water wall tubes in a 600 MW furnace at 300° while using CPT, CT, AVT(R) and AVT(O) water chemistry. In these water chemistry conditions, a layer of oxide film spontaneously forms in the furnace wall which could prevent corrosions in boiler water directly contact with the inner tube and reduce the probability of tube perforation.

The different morphologies, specific functions and distribution in the oxide film were identified by electrochemical workstation, XRD, SEM and EDAX.

It is concluded that metal surface was rugged and had deep corrosion in CPT. Ions penetrated into the oxides of large particles with gaps and intergranular corrosion occurred in CT conditions. In AVT(R), the oxide film uniformly covered on the metal surface played a protective role, but could be easily washed away by solution. The oxide film formed in AVT(O) was similar to AVT(R), but the difference is that large solid particles of Fe₂O₃ cover the outermost oxide film, which prevents the oxide film from being taken away by the flowing solution. In consequence, the degree of corrosion sustained by the tube walls is lowest in the case of AVT(O).

The results can provide reference for reducing the high temperature corrosion of metal in the actual operation.

The aim of this paper is to study the effect of the parametric sensitivity of all critical parameters of feed water and other operating variables on the corrosion rate and oxide scale deposition on economizer tubes of a typical coal-fired 250-MW boiler.

In this paper, a multilayer perceptron-based artificial neural network (ANN) model has been developed to envisage the corrosion rate and oxide scale deposition rate in economizer tubes of a coal-fired boiler. The neural network architecture has been optimized using an efficient gradient-based network optimization algorithm to minimize the training and testing errors rapidly during simulation runs.

The parametric sensitivity of all critical parameters of feed water and other operating variables on the corrosion rate and oxide scale deposition activities has been investigated. It has been observed that dissolved oxygen, dissolved copper content, residual hydrazine content and pH of the feed water have a relatively predominant influence on the corrosion rate, whereas dissolved iron content, silica content, pH and temperature of the feed water have a moderately major influence on oxide scale deposition phenomenon. There has been very good agreement between ANN model predictions and the measured values of corrosion rate and oxide scale deposition rate substantiated by the regression fit between these values.

This paper details the development of an alternative model to accurately predict corrosion rate and deposition rate on the inner surface of economizer tubes of a boiler over first principle-based kinetic model.

Examines the sixteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

With the proliferation of environmental science literature during the past two decades, librarians find it increasingly difficult to determine which sources of information are relevant to their clientele. This difficulty is compounded for the non‐science librarian by a lack of familiarity with journals currently available and the decidedly technical language of most environmental science publications. There are, however, a wide range of periodicals which are appropriate for informed readers at academic university libraries and public libraries that offer a wealth of information on the environmental sciences. It is this type of publication that will be identified in this annotated bibliography. As with all selected bibliographies, it does not attempt to identify all environmental science journal titles that may be used in an academic university library or public library. Titles selected will be those thought to be appropriate for the informed reader.

The contamination of groundwater by natural arsenic is currently a worldwide epidemic. Arsenic-contaminated groundwater has been reported in Argentina, Chile, Mexico, China, Hungary, West Bengal in India, Bangladesh, and Vietnam. Of these regions, Bangladesh and West Bengal are the most seriously affected in terms of the size of the population at risk and magnitude of health problems. Hence, chronic exposure to arsenic >50′′μg/L in drinking water can result in serious health problems. Common symptoms of arsenic-related ailments are skin, cardiovascular, renal, hematological, and respiratory disorders. Therefore, this chapter focuses on nature, origin, and extent of groundwater arsenic contamination, probable causes, and its impacts on food, drinking water, and social coverage. It further discloses mitigation approaches proposed and practiced by the different research groups to combat this problem and finally concludes.

This paper considers the use and application of the “grey system” modelling methodology for the prediction and characterisation of boiler water R‐values in electric power generating plants. It has been confirmed that the GM (1,1) model can pinpoint precisely the properties of the water chemistry cycle. It is considered that the grey system methodology can strengthen significantly the effectiveness of system diagnosis, thereby enabling the development and application of automated water chemistry management systems in power plants.

The purpose of this paper was to investigate the effects of SO₄2− concentration on the corrosion behaviour of T23 and T12 steels in simulated water chemistry condition solution of 600 MW fossil-fired power boilers.

The influence and mechanism of SO₄2− ions on the pitting corrosion of T23 and T12 steels in simulated oxygenated treatment water chemistry solution was studied using electrochemical potentiodynamic polarization scans and electrochemical impedance spectroscopy.

The results showed that T23 and T12 were susceptible to pitting corrosion in the simulated solution with full SO₄2− concentration for the competitive adsorption of OH− and SO₄2− on the surface of steels. The pitting sensitivity of the steels improved with increasing SO₄2− concentration. The corrosion resistance for SO₄2− of T23 was stronger than that for T12.

This study is an attempt to provide direction for regulating the concentration of SO₄2− in boiler water and for selecting the material for boiler water wall tubes.