Operational Experience With High Efficiency Cyclones: Comparison Between Boiler A and B in the Zeran Power Plant — Warsaw, Poland

2003 ◽  
Author(s):  
Ireneusz Lalak ◽  
Joachim Seeber ◽  
Frank Kluger ◽  
Stanislaw Krupka
Keyword(s):  
Heat Transfer ◽  
Power Plant ◽  
High Efficiency ◽  
Operational Experience ◽  
Significant Positive Effect ◽  
Internal Circulation ◽  
Technological Developments ◽  
The Impact ◽  
Positive Effect ◽  
Operational Data

The two 450t/h CFB units of the Zeran heat and power plant in Warsaw, Poland, are nearly identical in design, except for the cyclones. While the first CFB unit Zeran A which was commissioned in 1995 had cyclones of a prior design, the second unit Zeran B, which went into operation in late 2001, was equipped with high efficiency cyclones with the latest technological developments. The impact of the cyclone design is clearly visible in the operational data. Due to the high cyclone efficiency, the internal circulation became much higher and the fineness of the circulating particles was shifted to finer particles. As a result, the heat transfer in the furnace was boosted and the temperature profile became more even. This had a significant positive effect on the emissions, especially NOx and on the limestone consumption, which was considerably reduced.

Impact of Developments in HEI Correction Factors on Condenser Performance and Operation — A Case Study

2014 ◽  
Author(s):  
Komandur Sunder Raj
Keyword(s):  
Heat Transfer ◽  
Stainless Steel ◽  
Power Plant ◽  
Tube Bundle ◽  
Operational Experience ◽  
Correction Factors ◽  
7Th Edition ◽  
Surface Condenser ◽  
The Impact

The Heat Exchange Institute (HEI) Standards for Steam Surface Condensers were promulgated to design and predict the performance of surface condensers for power plant applications by providing basic overall tube bundle heat transfer rates and correction factors to be applied to account for different tube diameters, wall thicknesses (BWG), tube materials, circulating water inlet temperatures and, average water velocities. From 1958 to 1973, nonferrous alloys were generally the tube materials of choice for steam power plant surface condenser service. By the time the 7th edition of the HEI Standards was issued in 1978, concerns with corrosion and other issues with nonferrous tubing materials had led to increased specification of stainless steel while titanium was still in its infancy. Since then, operational experience gained with stainless steel and titanium coupled with technological advances in these materials have resulted in revisions and incorporation of additional correction factors in subsequent editions of the HEI Standards for Steam Surface Condensers. The latest edition (11th edition) was issued in October 2012. Significant developments in the HEI heat transfer correction factors since issuance of the 7th edition pertain to stainless steel and titanium. Using a case study, this paper analyzes the impact of developments in HEI heat transfer correction factors on steam surface condenser performance and operation with focus on admiralty, austenitic, super-austenitic and super-ferritic stainless steels as well as titanium tube materials. The paper examines how changes in the correction factors affect condenser performance and plant operation. It highlights the importance of using and validating the proper correction factors to predict and ensure optimum condenser performance and operation.

The impact of counterfeit risk management on healthcare supply chain performance: an empirical analysis

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mauro Falasca ◽  
Scott Dellana ◽  
William J. Rowe ◽  
John F. Kros
Keyword(s):  
Risk Management ◽  
Supply Chain ◽  
The United States ◽  
Equation Modeling ◽  
Significant Positive Effect ◽  
Healthcare Organizations ◽  
Content Type ◽  
Overall Performance ◽  
The Impact ◽  
Positive Effect

PurposeThis study develops and tests a model exploring the relationship between supply chain (SC) counterfeit risk management and performance in the healthcare supply chain (HCSC).Design/methodology/approachIn the proposed theoretical model, HCSC counterfeit risk management is characterized by HCSC counterfeit risk orientation (HCRO), HCSC counterfeit risk mitigation (HCRM) and HCSC risk management integration (HRMI), while performance is represented by healthcare logistics performance (HLP) and healthcare organization overall performance (HOP). Partial least squares structural equation modeling (PLS-SEM) and survey data from 55 HCSC managers are used to test the research hypotheses.FindingsHCRO has a significant positive effect on HCRM, while HCRM has a positive impact on HRMI. With respect to HLP, HCRM has a nonsignificant effect, while HRMI has a significant impact, thus confirming the important mediating role of HRMI. Finally, HLP has a significant positive effect on the overall performance of healthcare organizations.Research limitations/implicationsAll study participants were from the United States, limiting the generalizability of the study findings to different countries or regions. The sample size employed in the study did not allow the authors to distinguish among the different types of healthcare organizations.Originality/valueThis study delineates between a healthcare organization's philosophy toward counterfeiting risks vs actions taken to eliminate or reduce the impact of counterfeiting on the HCSC. By offering firm-level guidance for managers, this study informs healthcare organizations about addressing the challenge of counterfeiting in the HCSC.

IMPACT OF MICROFINANCE ON POVERTY ALLEVIATION IN ONDO STATE, NIGERIA

2012 ◽  
Vol 02 (09) ◽  
pp. 31-37
Author(s):  
AKINLO Anthony Enisan ◽  
ONI Isaac Oluwafemi
Keyword(s):  
Poverty Alleviation ◽  
Small Scale ◽  
Significant Positive Effect ◽  
Access To Credit ◽  
Economic Opportunities ◽  
Ondo State ◽  
The Impact ◽  
Positive Effect ◽  
Micro Credit

The paper examines the impact of microfinance on poverty alleviation in Ondo State, Nigeria. The paper is based on a survey of 240 beneficiaries of microcredit loans in Ondo State. The results of the analysis show that most beneficiaries of micro credit loans are educated youth between the age brackets of 18 and 40 years. Many of the beneficiaries utilized their loans to procure durable equipment needed in their small scale enterprises. The results show that loan empowerment has a significant positive effect on beneficiaries’ welfare. Access to credit allowed the beneficiaries take advantage of economic opportunities by providing a fundamental basis for planning and expanding business activities.

scholarly journals Latch-related nipple pain in breastfeeding women: the impact on breastfeeding outcomes

2020 ◽  
Vol 28 (7) ◽  
pp. 406-414
Author(s):  
Katie Bourdillon ◽  
Tom McCausland ◽  
Stephanie Jones
Keyword(s):  
Online Survey ◽  
Physical Symptoms ◽  
Breastfeeding Duration ◽  
Significant Positive Effect ◽  
Breastfeeding Rates ◽  
Perceived Impact ◽  
The Impact ◽  
Positive Effect ◽  
Mothers Experiences

Background Nipple pain is a common issue experienced by breastfeeding mothers and if not resolved, can contribute to early cessation of breastfeeding. Aims To investigate mothers experiences of nipple pain, the solutions used to manage their issues, and the perceived impact on breastfeeding outcomes with particular focus on latch-related nipple pain with no clear underlying cause (LRNP). Methods Data was collected via an online survey of UK-based women (n=1084). Findings LRNP was the most common issue as experienced by 52% of mothers surveyed. Various solutions were utilised to try to manage LRNP. Use of Highly Purified Anhydrous (HPA) Lanolin to manage LRNP was associated with a substantial increase in breastfeeding duration (average 33.2 weeks compared to 26.5 weeks for those who didn't report using HPA Lanolin). Discussion HPA Lanolin is a key solution used by mothers in the management of latch-related nipple pain and one which they perceive as having a significant positive effect on the physical symptoms and pain associated with nipple trauma. Use of HPA Lanolin was also associated with a substantial increase in breastfeeding duration which ultimately aids women in meeting their personal breastfeeding goals and improves overall breastfeeding rates.

scholarly journals Marketing Mix Elements and Corporate Social Responsibility: Do they Really Matter to Store Image?

2020 ◽  
Vol 9 (1) ◽  
pp. 56-71
Author(s):  
Jalal Rajeh Hanaysha
Keyword(s):  
Corporate Social Responsibility ◽  
Social Responsibility ◽  
Marketing Mix ◽  
Equation Modeling ◽  
Survey Method ◽  
Store Image ◽  
Significant Positive Effect ◽  
Corporate Social ◽  
The Impact ◽  
Positive Effect

This purpose of this article is to examine the impact of corporate social responsibility (CSR) and marketing mix elements on store image in Malaysian retail sector. The data were collected through a quantitative survey method from 278 customers of retail stores in eastern Malaysia. All of the returned questionnaires were inserted into SPSS and analyzed based on the structural equation modeling (SEM) technique using AMOS 18. The findings showed that CSR has a significant positive effect on store image. Furthermore, the outcomes revealed that advertising and price have significant positive effects on store image. However, the effect of sales promotion on store image is insignificant and negative. Finally, the results confirmed that store location and store environment have a significant positive effect on store image. The findings of this study contribute to our understanding with regard to the importance of these factors in influencing store image in the retail context.

scholarly journals Surviving Andersonville: The Benefits of Social Networks in POW Camps

2007 ◽  
Vol 97 (4) ◽  
pp. 1467-1487 ◽  
Author(s):  
Dora L Costa ◽  
Matthew E Kahn
Keyword(s):  
Social Networks ◽  
Death Rate ◽  
Union Army ◽  
Significant Positive Effect ◽  
Survival Probabilities ◽  
In Captivity ◽  
The Impact ◽  
Positive Effect

Twenty-seven percent of the Union Army prisoners captured July 1863 or later died in captivity. At Andersonville, the death rate may have been as high as 40 percent. How did men survive such horrific conditions? Using two independent datasets, we find that friends had a statistically significant positive effect on survival probabilities and that the closer the ties between friends as measured by such identifiers as ethnicity, kinship, and the same hometown, the bigger was the impact of friends on survival probabilities. (JEL N41, Z13)

Conjugate heat transfer simulation of turbine blade high efficiency cooling method with mist injection

2014 ◽  
Vol 228 (15) ◽  
pp. 2738-2749 ◽  
Author(s):  
Yuting Jiang ◽  
Qun Zheng ◽  
Guoqiang Yue ◽  
Ping Dong ◽  
Jie Gao ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Boundary Layer ◽  
Conjugate Heat Transfer ◽  
High Efficiency ◽  
Turbulence Models ◽  
Operating Conditions ◽  
Cooling Performance ◽  
Convective Cooling ◽  
Mist Cooling ◽  
The Impact

The idea of utilizing a finely dispersed water-in-air mixture has been proven to be a feasible technique to produce very high cooling rates. The accuracy of numerical simulation program for conjugate heat transfer methodology is verified with the Mark II transonic high pressure turbine stator which is cooled by internal convection through radial round pipes, and different turbulence models and transition models are employed to analyze the influence on results. On the basis of it, the mist cooling is simulated under typical gas turbine operating conditions for internal convective cooling to discuss the improvement of cooling performance. Though the results indicate that mist cooling can decrease the temperature of boundary layer without impact on the temperature of the mainstream and the thickness of boundary layer, the cooling capacity is limited by inadequate evaporation of mist. Considering the distribution of thermal stress and mist evaporation, a compound cooling blade of film cooling with trailing edge ejection is acquired which is modified from the blade of Mark II internal convective cooling; the effects of various parameters including mist concentration and mist diameter on the improvement of cooling performance are investigated, meanwhile the impact of curvature on cooling efficiency and mist trajectory is analyzed finally.

Through Flow Calculations for Convective Cooling Turbines

2014 ◽  
Author(s):  
Li Haibo ◽  
Chunwei Gu
Keyword(s):  
Heat Transfer ◽  
Gas Turbine ◽  
Calculation Method ◽  
Conjugate Heat Transfer ◽  
High Efficiency ◽  
Thermodynamic Efficiency ◽  
Inlet Temperature ◽  
Flow Calculation ◽  
Through Flow ◽  
The Impact

Conjugate heat transfer is a key feature of modern gas turbine, as cooling technology is widely applied to improve the turbine inlet temperature for high efficiency. Impact of conjugate heat transfer on heat loads and thermodynamic efficiency is a key issue in gas turbine design. This paper presented a through flow calculation method to predict the impact of heat transfer on the design process of a convective cooled turbine. A cooling model was applied in the through flow calculations to predict the coolant requirements, as well as a one-dimensional mixing model to evaluate some key parameters such as pressure losses, deviation angles and velocity triangles because of the injection cooling air. Numerical simulations were performed for verification of the method and investigation on conjugate heat transfer within the blades. By comparing these two calculations, it is shown that the through flow calculation method is a useful tool for the blade design of convective cooled turbines because of its simplicity and flexibility.

Validation of Advanced Steam Turbine Technology: A Case Study of an Ultra Super Critical Steam Turbine Power Plant

2011 ◽  
Author(s):  
Rainer Quinkertz ◽  
Thomas Thiemann ◽  
Kai Gierse
Keyword(s):  
High Pressure ◽  
Power Plant ◽  
Steam Turbine ◽  
Power Plants ◽  
High Efficiency ◽  
State Of The Art ◽  
Cooling System ◽  
Operational Experience ◽  
Internal Cooling ◽  
Steam Turbines

High efficiency and flexible operation continue to be the major requirements for power generation because of the benefits of reduced emissions and reduced fuel consumption, i.e. reduced operating costs. Ultra super critical (USC) steam parameters are the basis for state of the art technology of coal fired power plants with highest efficiency. An important part of the development process for advanced steam turbines is product validation. This step involves more than just providing evidence of customer guaranteed values (e.g. heat rate or electric output). It also involves proving that the design targets have been achieved and that the operational experience is fed back to designers to further develop the design criteria and enable the next step in the development of highly sophisticated products. What makes product validation for large size power plant steam turbines especially challenging is the fact that, due to the high costs of the required infrastructure, steam turbine manufacturers usually do not have a full scope / full scale testing facility. Therefore, good customer relations are the key to successful validation. This paper describes an extensive validation program for a modern state of the art ultra supercritical steam turbine performed at an operating 1000 MW steam power plant in China. Several measuring points in addition to the standard operating measurements were installed at one of the high pressure turbines to record the temperature distribution, e.g. to verify the functionality of the internal cooling system, which is an advanced design feature of the installed modern high pressure steam turbines. Predicted 3D temperature distributions are compared to the actual measurements in order to verify and evaluate the design rules and the design philosophy applied. Conclusions are drawn regarding the performance of modern 3D design tools applied in the current design process and an outlook is given on the future potential of modern USC turbines.

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