Economic Evaluation of Maintenance Strategies for Steam Generator Tubes Using Probabilistic Fracture Mechanics and a Financial Method

2007 ◽  
Vol 120 ◽  
pp. 119-126
Author(s):  
Yoshihiro Isobe ◽  
Mitsuyuki Sagisaka ◽  
Shinobu Yoshimura ◽  
Genki Yagawa
Keyword(s):  
Fracture Mechanics ◽  
Steam Generator ◽  
Net Present Value ◽  
Point Of View ◽  
Discounted Cash Flow ◽  
Pressurized Water ◽  
Economic Point ◽  
Probabilistic Fracture Mechanics ◽  
Water Reactors ◽  
Financial Indices

As an application of probabilistic fracture mechanics (PFM) and a financial method, a risk-benefit model was developed for the purpose of optimizing maintenance activities of steam generator (SG) tubes used in pressurized water reactors (PWRs). To justify whether or not it is worth while implementing the selected maintenance strategy in terms of an economic point of view, net present value (NPV) was calculated as an index which is one of the most fundamental financial indices for decision-making based on the discounted cash flow (DCF) method.

scholarly journals Engineering and Economic Perspective in The Production of Cu Nano

2020 ◽  
Vol 8 (1) ◽  
pp. 15
Author(s):  
Annisa Yuliandini ◽  
Asep Bayu Dani Nandiyanto
Keyword(s):  
Economic Evaluation ◽  
Net Present Value ◽  
Copper Acetate ◽  
Tween 80 ◽  
Point Of View ◽  
Industrial Scale ◽  
Sorbitan Monooleate ◽  
Economic Point ◽  
Economic Parameters ◽  
Break Even Point

The purpose of this study is to analyze the production of copper nanoparticles (Cu NPs) on an industrial scale in an engineering perspective and economic evaluation perspective. Energy is needed because of various energy related applications. Evaluation of Cu nanoparticle production in an engineering perspective is carried out from the selection of processes that are adapted to industrial scale, calculation of mass balance, to the adjustment of commercially available equipment. Evaluation of production from an economic point of view is done by calculating economic parameters: Gross Profit Margin, Internal Return Rate, Payback Period, Cumulative Net Present Value, Profitability Index, and Break Even Point. Briefly from the production process, we use Copper acetate hydrate (CuAc2.2H2O) (as a source of Cu), Tween 80 (polyoxyethylene-(80)-sorbitan monooleate) and ethylene glycol (as a reducing agent). The engineering viewpoint shows this process is capable of producing Cu nanoparticles which can be used as conductive nanoionic. Economic evaluation determines the process is beneficial, discussing with positive values ​​all economic parameters. However, for some variations this process is not profitable, so economic evaluation is needed.

U.S. Operating Experience With Thermally Treated Alloy 600 Steam Generator Tubes

2002 ◽  
Author(s):  
April Smith ◽  
Kenneth J. Karwoski
Keyword(s):  
Steam Generator ◽  
Operating Experience ◽  
Alloy 600 ◽  
Steam Generators ◽  
Pressurized Water ◽  
Steam Generator Tube ◽  
Water Reactors ◽  
1960S And 1970S ◽  
The 1960S ◽  
Thermally Treated

Steam generators placed in service in the 1960s and 1970s were primarily fabricated from mill-annealed Alloy 600. Over time, this material proved to be susceptible to stress corrosion cracking in the highly pure primary and secondary water chemistry environments of pressurized-water reactors. The corrosion ultimately led to the replacement of steam generators at numerous facilities, the first U.S. replacement occurring in 1980. Many of the steam generators placed into service in the 1980s used tubes fabricated from thermally treated Alloy 600. This tube material was thought to be less susceptible to corrosion. Because of the safety significance of steam generator tube integrity, this paper evaluates the operating experience of thermally treated Alloy 600 by looking at the extent to which it is used and recent results from steam generator tube examinations.

Investigations on Optimal Design of a U-Tube Steam Generator

2010 ◽  
Author(s):  
Hui-min Qin ◽  
Chang-qi Yan ◽  
Meng Wang ◽  
Shi-jing He
Keyword(s):  
Optimal Design ◽  
Steam Generator ◽  
Optimization Techniques ◽  
Point Of View ◽  
Geometric Constraints ◽  
Optimal Designs ◽  
Optimal Method ◽  
Obvious Effect ◽  
Pressurized Water ◽  
Performance Point

Steam generator is one of the key equipments in the pressurized water reactor, from the performance point of view, it is necessary to apply optimization techniques to the design of the steam generator. In this work, the optimal designs of a U-tube steam generator (UTSG), taking minimization of the total volume and net weight as objective respectively, are carried out by considering thermohydraulic and geometric constraints using a complex-genetic algorithm (CGA). And the sensitivities of some parameters which influence the total volume and net weight of UTSG are also analyzed. Under the condition of constant secondary thermalhydraulic parameters of the steam generator, the optimal design indicates an obvious effect taking either the overall volume or the total weight of the steam generator as the objective. The optimization results show that the proposed optimal method is feasible and effective. And the results of optimal designs and sensitivity analysis would provide guidance in the engineering design of UTSG.

Probabilistic Fracture Mechanics Benchmarking Study Involving the xLPR and PASCAL-SP Codes: Analysis by PASCAL-SP

2020 ◽  
Author(s):  
Akihiro Mano ◽  
Jinya Katsuyama ◽  
Yinsheng Li
Keyword(s):  
Fracture Mechanics ◽  
Stress Corrosion ◽  
Stress Corrosion Cracking ◽  
Nuclear Power ◽  
Power Plants ◽  
Corrosion Cracking ◽  
Energy Agency ◽  
Pressurized Water ◽  
Water Reactor ◽  
Probabilistic Fracture Mechanics

Abstract A probabilistic fracture mechanics (PFM) analysis code, PASCAL-SP, has been developed by Japan Atomic Energy Agency (JAEA) to evaluate the failure probability of piping within nuclear power plants considering aged-related degradations such as stress corrosion cracking and fatigue for both pressurized water reactor and boiling water reactor environments. To strengthen the applicability of PASCAL-SP, a benchmarking study is being performed with a PFM analysis code, xLPR, which has been developed by U.S.NRC in collaboration with EPRI. In this benchmarking study, deterministic and probabilistic analyses are undertaken on primary water stress corrosion cracking using the common analysis conditions. A deterministic analysis on the weld residual stress distributions is also considered. These analyses are carried out by U.S.NRC and JAEA independently using their own codes. Currently, the deterministic analyses by both xLPR and PASCAL-SP codes have been finished and probabilistic analyses are underway. This paper presents the details of conditions and comparisons of the results between the two aforementioned codes for the deterministic analyses. Both codes were found to provide almost the same results including the values of stress intensity factor. The conditions and results of the probabilistic analysis obtained from PASCAL-SP are also discussed.

scholarly journals Economic Evaluation and Techno-Economic Sensitivity Analysis of a Mass Integrated Shrimp Biorefinery in North Colombia

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2397
Author(s):  
Antonio Zuorro ◽  
Kariana Andrea Moreno-Sader ◽  
Ángel Darío González-Delgado
Keyword(s):  
Sensitivity Analysis ◽  
Economic Evaluation ◽  
Net Present Value ◽  
Raw Materials ◽  
Integrated Approach ◽  
Economic Feasibility ◽  
Point Of View ◽  
Economic Point ◽  
The North ◽  
Water Pinch

The high freshwater consumption requirements in shrimp biorefinery approaches represents one of the major drawbacks of implementing these technologies within the shrimp processing industry. This also affects the costs associated with the plant operation, and consequently, the overall economic performance of the project. The application of mass integration tools such as water pinch analysis can reduce frewshwater consumption by up to 80%, contributing to shrimp biorefinery sustainability. In this work, the economic evaluation and the techno-economic sensitivity analysis for a mass integrated approach for shrimp biorefinery were performed to determine the economic feasibility of the project when located in the North-Colombia region and to identify the critical techno-economic variables affecting the profitability of the process. The integrated approach designed to process 4113.09 tons of fresh shrimp in Colombia reaches a return on investment (%ROI) at 65.88% and a net present value (NPV) at 10.40 MM USD. The process supports decreases of up to 28% in capacity of production and increases of 12% and 11% in the cost of raw materials and variable operating costs without incurring losses, respectively. These findings suggest that the proposed design of the water recycling network coupled to a shrimp biorefinery approach is attractive from an economic point of view.

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