scholarly journals Investigation on ash fouling formation of induced fan blade and heat exchanger surface in a 1000MW coal-fired power plant

2020 ◽  
Vol 24 (6 Part A) ◽  
pp. 3477-3488
Author(s):  
He-Xin Liu ◽  
Jia-Fan Xiao ◽  
Hou-Zhang Tan ◽  
Yi-Bin Wang ◽  
Fu-Xin Yang
Keyword(s):  
Heat Exchanger ◽  
Power Plant ◽  
Power Plants ◽  
High Concentration ◽  
X Ray ◽  
Low Emission ◽  
Fan Blade ◽  
Main Component ◽  
Ash Fouling ◽  
Heat Exchanger Surface

The control of fouling deposition on the main equipment has always been an im-portant issue concerned by scientific research and industrial application. How-ever, severe fouling deposits on the induced fan blade and the low temperature economiser were found in a 1000 MW coal-fired power plant with ultra-low emission. The deposit samples were collected and analysed through X-ray dif-fraction spectrometer, X-ray fluorescence, elemental analyser and SEM with en-ergy dispersive spectrometers. The result shows that the deposits are mainly composed of tschermigite (NH4)Al(SO4)2 ? 12H2O, letovicite (NH4)3H(SO4)2, cal-cium sulphate CaSO4, and quartz SiO2. The ammonium sulphate is the main component of the fouling deposits. It acts as an adhesive and makes an important contribution to the deposition. The analysis shows that the ammonia slip from denitrification system and the unreasonable temperature setting are the main reasons for fouling deposition. It is suggested that the high concentration of am-monium slip at denitrification system and the rapid condensation of the sulphuric acid mist at heat exchanger should be paid more attention in coal-fired power plants.

Research on the Inspection Strategy Change Based on Risk-Informed Method in Nuclear Power Plant

2017 ◽  
Author(s):  
Ye Shuixiang ◽  
Li Qiongzhe ◽  
Xi Haiying
Keyword(s):  
Heat Exchanger ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
System Component ◽  
Informed Decision Making ◽  
Inspection Strategy ◽  
Strategy Change ◽  
Generation Activity

In order to gain more operational benefits, many nuclear power plants will intend to optimize the generation activity to increase generating capability factor, such as, shortening the refueling schedule by optimize the inspection strategy of relevant to SSCs (structure, system, component) during reactor shutdown. Therefore, this paper will introduce the research on the inspection strategy change based on risk-informed method, and provide detailed discussion on change of the RHR heat exchanger inspection strategy by employed the above mentioned method in one nuclear power plant. The result shows that the optimization of RHR heat exchanger inspection strategy meets all the consideration of the principles in risk-informed decision-making required by RG 1.174 and the optimization proposal is acceptable.

Low-Frequency Vibroisolation Mounting of Power Plants for New Generation Airplanes with Engines of Extra-High by-Pass Ratio

2008 ◽  
Vol 39 (10) ◽  
pp. 11-17
Author(s):  
Viatcheslav S. Baklanov
Keyword(s):  
Power Plant ◽  
Power Plants ◽  
Low Frequency ◽  
Fan Noise ◽  
Oscillation Modes ◽  
Basic Source ◽  
Fan Blade ◽  
Blade Frequency ◽  
High Level ◽  
New Generation

Compliance of aircraft with new noise standards defines the tendency to switch to extra-high bypass ratio engines. Substantial noise redistribution has occurred in the aircraft of the new generation. While jet noise has been reduced dramatically, the engine still remains the basic source of noise, which is a fan noise. In the forward hemisphere, beside the discrete components at fan blade frequency, long row of discrete components has been observed around the principal blade frequencies as result of shockwave influence. This phenomenon is called “buzz-saw noise”. Fan shaft frequency reduction is one of the necessary measures for shockwaves control. Due to the decrease of frequency, the vibration spectrum shifts towards the low-frequency range. Such components will determine dynamical impact spectrum of power plant, transmitted through mounting to the airframe construction. An airframe typically possesses dozens of oscillation modes in the low-frequency spectrum part. Interaction of some of them with the influence of power plant may generation of discrete low-frequency high-level noise components in cabin. We have designed a new low frequency attachment containing built-in elastic elements with non-linear characteristics and with quasi-zero stiffness zone at proof load by cruise mode.

scholarly journals Assessment of Thermo-Electric Power Plants for Rotorcraft Application

2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Ioannis Roumeliotis ◽  
Christos Mourouzidis ◽  
Mirko Zafferetti ◽  
Deniz Unlu ◽  
Olivier Broca ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Power Plant ◽  
Electric Power ◽  
Gas Turbine ◽  
Power Plants ◽  
Simple Cycle ◽  
Specific Power ◽  
Transient Operation ◽  
Thermo Electric ◽  
Hybrid Configuration

Abstract This paper assesses a parallel electric hybrid propulsion system utilizing simple and recuperated cycle gas turbine configurations. An adapted engine model capable to reproduce a turboshaft engine steady state and transient operation is built in Simcenter Amesim and used as a baseline for a recuperated engine. The transient operation of the recuperated engine is assessed for different values of heat exchanger effectiveness, quantifying the engine lag and the surge margin reduction which are results of the heat exchanger addition. An oil and gas (OAG) mission of a twin engine medium helicopter has been used for assessing the parallel hybrid configuration. The thermoelectric system brings a certain level of flexibility allowing for better engine utilization, thus first a hybrid configuration based on simple cycle gas turbine scaled down from the baseline engine is assessed in terms of performance and weight. Following the recuperated engine, thermoelectric power plant is assessed and the performance enhancement is compared against the simple cycle conventional and hybrid configurations. The results indicate that a recuperated gas turbine based thermo-electric power plant may provide significant fuel economy despite the increased weight. At the same time, the electric power train can be used to compensate for the reduced specific power and potentially for the throttle response change due to the heat exchanger addition.

Use of Condensing Heat Exchangers in Coal-Fired Power Plants to Recover Flue Gas Moisture and Capture Air Toxics

2013 ◽  
Author(s):  
Edward Levy ◽  
Harun Bilirgen ◽  
Joshua Charles ◽  
Mark Ness
Keyword(s):  
Water Vapor ◽  
Heat Exchanger ◽  
Power Plant ◽  
Flue Gas ◽  
Heat Exchangers ◽  
Power Plants ◽  
Operating Conditions ◽  
Dew Point ◽  
Air Toxics ◽  
Condensing Heat Exchanger

Heat exchangers, which cool boiler flue gas to temperatures below the water vapor dew point, can be used to capture moisture from flue gas and reduce external water consumption for power plant operations. At the same time, thermal energy removed from the flue gas can be used to improve unit heat rate. Recent data also show that emissions of air toxics from flue gas would be reduced by use of condensing heat exchangers. This paper describes results from a slip stream test of a water cooled condensing heat exchanger system at a power plant with a lignite-fired boiler. The flue gas which flowed through the heat exchangers had been extracted from a duct downstream of the electrostatic precipitator. Measurements were made of flue gas and cooling water temperatures, flue gas water vapor concentrations, and concentrations of elemental and oxidized Hg at the inlet and exit of the heat exchanger system. Condensed water was also collected and analyzed for concentrations of H2SO4 and HCl. Results on the effects of the condensing heat exchanger operating conditions on oxidation and capture of Hg and on the capture of sulfuric and hydrochloric acids are described.

Application of field portable X-ray fluorescence to the analysis of desert varnish samples in areas affected by coal-fired power plants

2012 ◽  
Vol 9 (4) ◽  
pp. 379 ◽  
Author(s):  
Piotr Nowinski ◽  
Vernon F. Hodge ◽  
Shawn Gerstenberger
Keyword(s):  
Air Pollution ◽  
Power Plant ◽  
Power Plants ◽  
Tracer Concentration ◽  
X Ray ◽  
Desert Varnish ◽  
Geographical Regions ◽  
Rock Coatings ◽  
Fluorescence Spectrometer ◽  
Non Destructive

Environmental context Rock surfaces are often covered with a dark coating called desert varnish that can capture and retain air pollutants. A field portable X-ray fluorescence spectrometer was used for direct non-destructive analysis of varnished rocks in the fallout zones of two coal-fired power plants. At one power plant where tracer studies had been carried out, the highest concentration of elements including Cr, As, Pb and Zn in the rock varnish samples, coincides with the peak tracer concentration locations. AbstractDesert varnish samples were collected near two coal-fired power plants to determine if the varnish contained a record of recent air pollution. Samples were collected: (1) in the fallout patterns of the shuttered Mohave Power Plant (MPP), located in Laughlin, NV; and (2) near the operating Reid-Gardner Power Plant (RGPP), just east of Las Vegas, NV. Small pieces of varnished rocks were analysed by field portable X-ray fluorescence spectroscopy (FPXRF). Results were obtained for 15 elements: Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, Mo, Hg and Pb. The FPXRF data indicate that the elements commonly found in fly ash from coal-fired power plants (e.g. Cr, Zn, As and Pb) had significantly higher concentrations in the rock coatings in relation to the unvarnished substrate rock. For one of the power plants, where tracer plume studies had been carried out, the highest concentrations in the desert varnish coincided with the peak tracer concentration locations. Thus, these elements in desert varnish hold promise for identifying those geographical regions affected by nearby power plants. However, additional samples are required to demonstrate unequivocally that the power plants are indeed the sources of these elements. Overall, it is apparent that desert varnish can be utilised as a passive environmental monitor to investigate recent air pollution (past 20–30 years) and that FPXRF can be used as a surveying tool to obtain multi-element data from a large number of samples.

Methods to Define Failure Probability for Power Plant Heat Exchangers

2017 ◽  
Author(s):  
Carolyn J. John ◽  
Consuelo E. Guzman-Leong ◽  
Thomas C. Esselman ◽  
Sam L. Harvey
Keyword(s):  
Heat Exchanger ◽  
Power Plant ◽  
Fresh Water ◽  
Heat Exchangers ◽  
Power Plants ◽  
Operating Experience ◽  
Operating Conditions ◽  
Microbiologically Influenced Corrosion ◽  
Water Steam ◽  
Over Time

In response to the technical challenges faced by aging plant systems and components at nuclear power plants (NPP), the Electric Power Research Institute (EPRI) has a product entitled Integrated Life Cycle Management (ILCM). The ILCM software is a quantitative tool that supports capital asset and component replacement decision-making at NPPs. ILCM is comprised of models that predict the probability of failure (PoF) over time for various high-value components such as steam generators, turbines, generators, etc. The PoF models allow the user to schedule replacements at the optimum time, thereby reducing unplanned equipment shutdowns and costs. This paper describes a mathematical model that was developed for critical heat exchangers in a power plant. The heat exchanger model calculates the probability of the tubes, shell, or internals failing individually, and then accumulates the failures across the heat exchanger sub-components. The dominant degradation mechanisms addressed by the model include stress corrosion cracking, wear, microbiologically influenced corrosion, flow accelerated corrosion, and particle-induced erosion. The heat exchanger model combines physics-based algorithms and operating experience distributions to predict the cumulative PoF over time. The model is applicable to shell and tube heat exchangers and air-to-water heat exchangers. Many different types of fluids including open cycle fresh water, closed cycle fresh water, sea water, brackish water, air, closed cooling water, steam, oil, primary water, and condensate are included. Examples of PoF over time plots are also provided for different fluid types and operating conditions.

Application of PTFE Heat Exchanger in Low Temperature Waste Heat of Big Coal-Fired Power Plants

2015 ◽  
Vol 789-790 ◽  
pp. 503-507 ◽  
Author(s):  
Wen Peng Hong ◽  
Hui Zhang
Keyword(s):  
Heat Exchanger ◽  
Power Plant ◽  
Low Temperature ◽  
Thermal Power Plant ◽  
Power Plants ◽  
Waste Heat ◽  
Rapid Development ◽  
Thermal Power ◽  
Power Plant Boiler ◽  
Plant Boiler

With the rapid development of the national economy, the use of low-temperature heat in thermal power plant boiler can not be ignored.Although low temperature economizer is widely used in low-temperature waste heat recovery of thermal power plant boiler, the problems of corrosion and fouling are very significant.New type PTFE heat exchanger filled with high thermal conductivity properties can replace the existing metal heat exchanger, fundamentally solve the problems of corrosion and fouling, meet the future development of the thermal power plant, and realize the energy recycling to maximize the benefit of energy.

scholarly journals Modification of a Ceramic Brick Additives of Inorganic Technogenic Products of Water Treatment of Combined Heat and Power Plant

2020 ◽  
Vol 19 (3) ◽  
pp. 204-214
Author(s):  
A. S. Kauchur ◽  
V. K. Sheleh ◽  
V. I. Zhornik ◽  
S. A. Kovaliova
Keyword(s):  
Water Treatment ◽  
Power Plant ◽  
Power Plants ◽  
Raw Materials ◽  
Combined Heat And Power ◽  
Ceramic Brick ◽  
X Ray ◽  
Ir Studies ◽  
Inorganic Waste ◽  
Chemical Water

Waste of combined heat and power plants represents a certain danger to the environment, and hence the economic problems. However such waste contains substances that are advisable to use for production of construction and finishing materials. Technogenic products of water treatment from the Yuzhnaya combined heat and power plant (sludges of chemical water treatment – code 8410500) are a calcite mixture containing more than 64 wt. % calcite. The mineralogical composition of inorganic waste has been determined while using X-ray and IR-spectral researches. Mechanical activation of calcite inorganic wastes leads to grinding of calcite and a decrease in the amount of adsorbed water, which affects the increase in the content of silica frame structures, the reactivity of which directly depends on their quantity. Changes in the structure of silicon dioxide during mechanical activation are established according to IR studies. The results of X-ray and IR studies of the Zapolie deposit clay used in ceramic brick production technology make it possible to attribute it to raw materials with high reactivity. An experimental batch of ceramic bricks has been produced at JSC “Obolsky Ceramic Plant” with addition of calcite inorganic waste from combined heat and power plants. An X-ray diffraction analysis of samples of the obtained bricks having standard composition and with addition of waste has been carried out. The influence of calcite inorganic waste content in the feedstock on the process of ceramic brick structure formation has been stu-died in the paper. Addition of chemical water treatment waste containing calcium carbonate up to 15 wt. % to the Zapolye clay mixture helps to reduce a firing temperature and an appearance of the melt. This leads to crystallization processes of solid minerals from the melt and an increase in the amount of glass phase which contributes to improvement of strength properties in ceramic bricks. The possibility of using inorganic waste (sludges of chemical water treatment – code 8410500) of combined heat and power plants as a component of emaciated additives in clay raw materials in the process of ceramic brick production has been established in the paper.

scholarly journals Analysis and Treatment Measures of Continuous Emission Monitoring System Fouling in a Coal-Fired Power Plant after Ultra-Low Emission Transformation

2020 ◽  
Vol 71 (5) ◽  
pp. 239-250
Author(s):  
Zhenmin Zhang ◽  
Yujie Zhu ◽  
Jianjun Shen ◽  
Anqi Tu ◽  
Yu Wu ◽  
...  
Keyword(s):  
Power Plant ◽  
Phosphoric Acid ◽  
Monitoring System ◽  
Continuous Emission ◽  
X Ray Diffraction ◽  
X Ray ◽  
Emission Monitoring ◽  
Low Emission ◽  
Treatment Measures ◽  
Continuous Emission Monitoring

Scanning electron microscopy (SEM) micro-morphology analysis, X-ray diffraction (XRD) and energy-dispersive X-ray diffraction (EDX) component analysis were conducted on the fouling of continuous emission monitoring system (CEMS) sampling tube at the outlet of limestone-gypsum wet flue gas desulfurization (WFGD) of unit 1 in a 600 MW supercritical coal-fired power plant in Inner Mongolia Autonomous Region. The results show that the main component of fouling was ammonium dihydrogen phosphate, which was generated by the reaction between phosphoric acid in the phosphoric acid titration device and the NH3 escaping from the selective catalyst reduction (SCR) denitrification system, and corresponding treatment measures were taken. It indicates that the average value of ammonia escape was reduced from 1.79 ppm to 1.54 ppm through the ammonia injection optimization test of the SCR denitrification system (at the load of 410 MW of the unit), which effectively reduced the generation of fouling. This research provides reference for improving the reliability of coal-fired unit operation after ultra-low emission transformation.

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