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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.

This article describes a new humidity sensor using the technique of differential thermal analysis (DTA). The energy of water vaporisation is estimated via the measurement of the Seebeck voltage of miniature thermocouples used in differential mode on a Peltier module causing condensation from the ambient air. This sensor uses the sensitivity of alloys V2VI3 containing [Bi, Te, Sb, Se], 400‐440μV.K^–1. Experimental measurements have been performed in a climatic chamber at constant temperature. The time variation of the differential Seebeck voltage with relative humidities H_R varying from 10 to 90 per cent makes it possible to identify with precision the point of water evaporation. For each value of the relative humidity, it is directly a function of the condensate mass. The integration of these curves over time makes it possible to calculate the energy of vaporisation and the condensate mass.

Sour water condensates are aqueous condensates which contain different concentrations of aggressive compounds such as HCl, H2S, CO2, NH3, cyanides, etc. These condensates which can be fairly corrosive are encountered in a variety of refinery processes ranging from atmospheric distillation units to hydrodesulphurisers and sour water strippers. This paper deals with the mechanism of corrosion by these condensates and the factors influencing corrosion in several typical refinery units. In addition, methods for corrosion prevention and control are also discussed.

A three‐dimensional numerical analysis was carried out to study in detail the combined heat and mass transfer processes between a moist air flow and a cooled surface when film condensation occurs. A cross‐flow was considered between the air flow and the film flow. A turbulent flow was modelled using the Wilcox k−ω turbulence model. The shape of the interface between the air and the film was treated as a moving boundary, and it was calculated with the assumptions that the interface ways remain an interface, the stress at the interface is continuous and that there is no slip at the interface. Numerical results were obtained by solving simultaneous coupled equations of the air, film and solid. The results show that the condensate film flow has a significant effect on the extended surface temperature distribution and consequently on its efficiency. It is shown that the simultaneous influence of gravity and the air flow on the condensate film results in an asymmetric velocity profile in the film as well as in the asymmetric shape of the film.

The advantages of reclaiming as much condensate as possible in any steam‐generating system are manifest. The return of hot water to the boiler results in a considerable reduction in fuel and water consumption. In addition, a low make‐up will give rise to a lower rate of corrosion attack due to carbon dioxide generated from dissolved bicarbonates. However, such a procedure greatly increases the length of piping and number of fittings which are exposed to attack. The corrosion of steam and condensate return lines, and also of steam‐using equipment, can become a major problem. Perforation of steam jackets, steam coils, pipes and fittings; choking of steam traps with corrosion products; leaking valves and joints are serious enough in themselves. The cost of replacing the corroded equipment is often considerable and excessive damage may be caused by the ingress of steam or water to the product being manufactured. In addition, a very high labour cost is often involved. Repairs to damaged plant must usually take place at weekends and during holiday time, when overtime rates are paid.

The purpose of this paper is to present the technique for evaluating the performance of a condensate system of a coal-based thermal power plant situated in the northern part of India. The data which used for system availability evaluation are not precise and are uncertain and, further, collected from concerned power plant history sheets and from discussion through plant personnel.

In the proposed model, traditional Markov birth-death process using a probabilistic approach is used to analyze the performance of a complex repairable condensate system of power plant up to a desired degree of accuracy. This approach has been demonstrated by breaking the condensate system into six subsystems arranged in series with two feasible states, namely, working and failed, labeled in a transition diagram and modeled as a Markov process, using Chapman–Kolmogorov equations, which are used for development of a probabilistic stochastic model for availability analysis in a more effecting manner, considering some suitable assumptions.

This study of analysis of reliability and availability can help in increasing the plant production and performance. The analysis is done with the help of availability matrices, which are developed using different combinations of failures and repair rates of all subsystems. To achieve the goal of maximum power generation, it is required to run the various subsystem of the concerned system of plant, failure free for a long duration. Therefore, the present approach may be a more powerful analysis tool to access the performance of all subsystems of a condensate system in terms of availability level achieved in availability matrices. The results of present study are found to be highly beneficial to the plant management for making maintenance decisions.

The present paper suggests a suitable technique for stochastic modeling and availability evaluation of an industrial system using Markovian approach and drawing a transition diagram to represent the operational behavior of the system. The present methodology includes the advantage of the ability to model and develop a more complex industrial system and helps in improving the performance and handling the uncertainties and possibilities of an industrial system.

This paper aims to evaluate the concentration effect of red mud waste filler on mechanical and thermal properties of amine functional aniline furfuraldehyde condensate (AFAFFC) modified epoxy composite along with the optimum result of modified epoxy.

For effective toughening, different compositions were made by adding various concentration of AFAFFC to epoxy. The concentration of 2, 5 and 10 parts per hundred parts of epoxy resin of aluminium silicate-based pristine red mud waste was incorporated into the each modified epoxy matrix. These filled modified matrixes were cured with ambient temperature curing agent triethylene tetramine and evaluated with respect to their impact, tensile and flexural strengths. The morphology was analyzed by scanning electron microscopy and dynamic mechanical analysis. The thermal stability by thermogravimetric analysis was also reported.

The modification of epoxy resin using AFAFFC and filler showed significant enhancement of mechanical strength over unmodified epoxy. The increase depends on the concentration of the modifier and filler. The reason behind this is that in the initial stage of curing, the AFAFFC are miscible with the epoxy and form a homogeneous solution. This good mixing promotes the chemical reaction and network formation. During the curing process, as the molecular weight increases, the component separates with in the reaction medium to form a second dispersed phase.

The present paper discussed the effect of only one type of modifier, i.e. AFAFFC, and one filler, i.e. red mud waste filler effect. Besides these by changing the amine and aldehyde, other modifiers could be synthesised and the efficiency of modification of epoxy resin using these modifiers and other filler besides red mud waste such as paddy husk, bamboo dust, etc., could also be studied.

The present study regarding the concentration effect of modifier and filler was novel, and AFAFFC modified filled epoxy could be used in the field of coating, casting, adhesives, potting and encapsulation of semiconductor devices.

The purpose of this paper is to propose a cradle-to-cradle (C2C) zero discharge production planning system with a fuzzy hybrid optimization model that uses fuzzy comprehensive evaluation to establish fuzzy indicators, and then defuzzify the fuzzy indicators to construct a fuzzy multiobjective programming (FMOP) model.

The FMOP model pursues overall satisfaction using a particle swarm optimization algorithm to produce the best output values for the maximum waste paper recovery rate, the condensate reuse quality and minimum total cost of the zero discharge production planning system.

Recovered waste heat is seldom recycled and consumed in Taiwan. There is a need to capture and utilize heat recovery and use it in the production process supply. In contrast, waste materials are used as resources to perform waste paper recovery and recycle the waste heat of evaporation collection in the production process.

This paper develops a system to establish the best output value for an overall high satisfaction level. According to the results, the waste paper recovery rate is 99.8 percent, condensate reuse quality water is 102.6 tons and the total cost of the zero discharge production planning system is NT$1,312,012.

The purpose of this paper is to evaluate the improvement of mechanical and thermal properties of cured epoxy modified with amine functional chloroaniline formaldehyde condensate (AFCFC) and to determine the optimum level of modification.

To evaluate toughening, different compositions were made by adding various concentration of AFCFC to epoxy. The impact, adhesive, tensile and flexural strengths of the modified and the unmodified epoxy were characterised by dynamic mechanical analysis. Thermogravimetric properties of modified epoxy were also reported.

The modification of epoxy resin using AFCFC showed significant enhancement of mechanical strength over unmodified epoxy. The reason behind this is that, in the initial stage of curing, the AFCFC are miscible with the epoxy and form a homogeneous solution. This homogeneity promotes the chemical reaction and network formation. During the curing process, as the molecular weight increases, the component separates within the reaction medium to form a second dispersed phase.

The toughening agent AFCFC has been synthesised by using chloroaniline and formaldehyde. By changing amine and aldehyde, other toughening agents could be synthesised and the efficiency of modification of epoxy resin using these could also be studied.

AFCFC modified epoxy could be used in the field of coating, casting, adhesives, potting and encapsulation of semiconductor devices.

To evaluate the improvement of mechanical and thermal properties of cured epoxy modified with amine functional aniline formaldehyde condensate (AFAFC) along with the optimum result of modified epoxy.

For effective toughening, different compositions were made by adding various concentration of AFAFC to epoxy. The impact, adhesive, tensile and flexural strengths of the modified and the unmodified epoxy were characterized by dynamic mechanical analysis. Thermo gravimetric of modified epoxy was also reported.

The modification of epoxy resin using AFAFC showed significant enhancement of mechanical strength over unmodified epoxy. The reason behind this is that in the initial stage of cure the AFAFC are miscible with the epoxy and form a homogeneous solution. This good mixing promotes the chemical reaction and network formation. During the curing process, as the molecular weight increases, the component separates with in the reaction medium to form a second dispersed phase.

The toughening agent AFAFC have been synthesized by using aniline and formaldehyde. Besides this, by changing the amine and aldehyde, another toughening agent could be synthesized and the efficiency of modification of epoxy resin using these could also be studied.

AFAFC modified epoxy could be used in the field of coating, casting, adhesives, potting and encapsulation of semiconductor devices.