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The purpose of this study was to investigate the corrosion of low molecular organic acids from water-steam cycles such as acetic acid and formic acid in mental parts of steam turbine initial condensation zone.

The corrosion behavior of gray cast iron in initial condensate containing different concentrations of acetic acid and formic acid was studied by weight loss test, scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction.

The results indicated that gray cast iron had a certain degree of corrosion in the simulated initial condensate containing acetic acid and formic acid, but the acid corrosion of gray cast iron was not only caused by low molecular organic acid but also affected by inorganic anions such as Cl⁻. When Cl⁻ existed, after removing corrosion products, surface analysis results proved that the surface of gray cast iron was rough and uneven with many cracks, which was corrected more serious.

The corrosion behavior of thermal equipment by low molecular organic acids and inorganic anions in water-steam cycles was studied. The research results can provide theoretical guidelines for corrosion control of steam turbine in power plants.

Methods used to prevent the corrosion of feed line surfaces and minimise accumulation of corrosion product in the feed water are mentioned in this article, including acid washing prior to operation and the use of volatile and filming amines as inhibitors. The type of corrosion occurring on the steam side of the cupro‐nickel feed heater tubes and in the mild‐steel surge tanks of the closed‐circuit water steam cycle of C.E.G.B. boiler plant is described in some detail.

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 describe the process of synthesizing lamellarly‐shaped anticorrosion pigments having a chemically active layer whose core consists of metal aluminium on which a thin spinel film is synthesised.

Anticorrosion pigments were synthesised by reaction of metal aluminium lamellar particles whose surface was oxidised to Al₂O₃ during the first stage and by subsequent reaction with ZnO and/or MgO at 800‐1,150°C producing a thin spinel layer that is chemically bonded to the metal core of the pigment particles. Core‐shell pigments including MgAl₂O₄/Al, Mg_0.8Zn_0.2Al₂O₄/Al, Mg_0.6Zn_0.4Al₂O₄/Al, Mg_0.4Zn_0.6Al₂O₄/Al, Mg_0.2Zn_0.8Al₂O₄/Al and ZnAl₂O₄/Al were synthesised. The prepared pigments were characterised by means of X‐ray diffraction analysis and scanning electron microscopy. The synthesised anticorrosion pigments were used to prepare epoxy coatings that were tested upon application for their anticorrosion properties and resistance against a chemical environment.

The lamellar shape of the particles, as well as good‐quality coverage with a thin spinel layer, was identified in the prepared pigments. All of the synthesised pigments exhibit good anticorrosion efficiency in epoxy coatings. Compared to lamellar kaolin and metal core of aluminium without coverage, the protective function of the synthesised pigments in coatings is demonstrably better.

The synthesised pigments find convenient applications in coatings protecting metal bases from corrosion.

Synthesis of a spinel layer on the metal core of aluminium is a novel method; so is the application of these substances in coatings designed for the protection of metals from corrosion. Of great benefit is the fact that the synthesised pigments are free of any substances harmful to the environment.

Integrated solar combined cycle (ISCC) using parabolic trough collector (PTC) technology is a new power plant that has been installed in few countries to benefit from the use of hybrid solar-gas systems. The purpose of this paper is to investigate the challenges in modeling the thermal output of the hybrid solar-gas power plant and to analyze the factors that influence them.

To validate the proposal, a study was conducted on a test stand in situ and based on the statistical analysis of meteorological data of the year 2017. Such data have been brought from Abener hybrid solar-gas central of Hassi R’mel and used as an input of our model.

The proposal made by the authors has been simulated using MATLAB environment. The simulation results show that the net solar electricity reaches 18 per cent in June, 15 per cent in March and September, while it cannot exceed 8 per cent in December. Moreover, it shows that the power plant responses sensibly to solar energy, where the electricity output increases accordingly to the solar radiation increase. This increase in efficiency results in better economic utilization of the solar PTC equipment in such kind of hybrid solar-gas power plant.

The obtained results would be expected to provide the possibility for designing other power plants in Algeria when such conditions are met (high DNI, low wind speed, water and natural-gas availability).

This paper presents a new model able to predict the thermal solar energy and the net solar-electricity efficiency of such kind solar hybrid power plant.

The design and retrofit of the heat exchangers in a boiler should take into account the processes occurring on the side of combustion and steam. For this reason, this study aims to couple a one-dimensional hydrodynamic model of steam with computational fluid dynamics (CFD) simulation of flue gas.

Radiant/semi-radiant platen heat exchangers are simplified as plane surfaces for CFD, while convective heat exchangers are introduced into the CFD simulation as energy/momentum absorption sources.

Numerical simulation is performed for a 1,000 MWe coal-fired ultra-supercritical boiler. The calculation results are validated by the thermodynamic design data. Tube outside surface temperature, as well as ash deposit temperature distributions, are obtained.

Complex tube arrangements can be completed with the aid of AutoCAD, and therefore, the simulation could offer detailed information of heat exchangers. In a word, a more reliable modeling of the whole steam generation process is achieved.

The purpose of this paper is to evaluate the energy, economic and environmental performance of commercial water heating systems in Hong Kong special administrative region (SAR), China.

The research team contacted 50 facilities managers in Hong Kong, and 16 of them agreed to participate in this territorial-wide survey. The overall efficiency of different water heating systems was determined through measurements of inlet water temperatures, outlet steam/water properties, the amount of steam/water produced and the amount of energy consumed. The cost effectiveness and the amount of greenhouse gases produced per megajoule (MJ) output were also determined.

Results show that electric water heating systems had the highest mean overall efficiency, followed by gas- and oil-fired systems. However, the difference between the mean overall efficiency of the three types of water heating systems was not statistically significant, as the systems had been inspected and maintained regularly. Oil-fired systems were found to be the most cost-effective when taking fuel prices into consideration. Environmental analysis showed that gas-fired systems produced the least amount of greenhouse gases per MJ output.

Water heating is one of the major uses of energy in buildings. Hence, the efficiency of a water heating system can have a significant effect on the overall performance of a building. This paper not only provides insight on the energy performance but it also evaluates the economic and environmental performance of water heating systems.

This chapter aims to identify new perspectives of geothermal energy investments. For this purpose, all studies in the Web of Science regarding the geothermal energy are taken into consideration. These studies are evaluated with the help of text-mining approach. In this framework, most frequently stated words, two words, and three words are identified. It is concluded that technological development with respect to the geothermal energy is an important issue in this framework. After that, it is also determined that risk is another important factor in this regard. Finally, new implications regarding the geothermal energy are also considered by the researchers. Geothermal energy has a positive contribution to solve many different problems, such as energy dependency, current account deficit problem, and carbon emission. Hence, this study generated the significant issues to improve these investments. While considering the results, it is understood that technological developments related to the geothermal energy projects should be followed effectively. In addition, an effective risk evaluation should be conducted before implementing these projects.

Colleges and universities that are interested in reducing their environmental impacts are faced with the difficulties of providing incentives for sustainable behavior and attempting to quantify the gains that policies would provide. In this paper, we use a case study to demonstrate the benefits as well as the difficulties encountered with one type of incentive program, a revolving loan fund. During the five‐year tenure of the case study fund, the program yielded a 34 percent return on conservation investments, with associated decreases in resource usage, ambient air emissions, and water consumption. Using a past damage function study, we estimate that the reduced emissions result in over US$100,000 of avoided environmental externalities per year. Although the economic returns and environmental benefits were significant, participation declined rapidly after the initial rollout of the program and relatively non‐technical conservation measures were generally the focus of projects. Through surveys of both participating and non‐participating facility directors, we determined that lack of knowledge of effective conservation measures and limitations in staff availability were the key barriers preventing more extensive participation. Increased flow of information, through such actions as frequent facility director correspondence and independent energy audits of facilities, would be likely to encourage sustainable resource consumption in future applications of revolving loan funds and other campus greening efforts.

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