Rejection of Waste Heat From Power Plants Through Phased-Cooling

1975 ◽  
Vol 97 (1) ◽  
pp. 117-124
Author(s):  
J. A. MacFarlane ◽  
J. S. Goodling ◽  
G. Maples
Keyword(s):  
System Performance ◽  
Power Plants ◽  
Heat Dissipation ◽  
Waste Heat ◽  
Cooling Water ◽  
Meteorological Conditions ◽  
Optimum Number ◽  
Cooling Systems ◽  
Storage Pond ◽  
Power Plant Cooling

Because of the disadvantages associated with present power plant cooling systems, a new concept in waste heat dissipation, called “phased-cooling”, is introduced. Heated condenser cooling water is held in a storage pond during certain hours of the day, to be cooled at a later time by traveling across a cooling surface. A thermodynamic analysis of the system is performed, and the equations of heat transfer from a water surface are presented. The developed model is then used for prediction of system performance. The optimum number of storage hours is shown to be dependent upon the size of the system, the season, and meteorological conditions. Phased-cooling evaporation losses are approximately 40 percent less than those of cooling towers and cooling ponds. Condenser inlet temperatures are significantly lower than those of cooling ponds of similar size.

Waste Heat Recovery and Saving Fresh Water Consumption in Power Plants

2012 ◽  
Author(s):  
Kwangkook Jeong
Keyword(s):  
Power Plant ◽  
Fresh Water ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Power Plants ◽  
Waste Heat ◽  
Combined Cycle ◽  
Water Recovery ◽  
Cooling Effects ◽  
Power Plant Cooling

A section to delineate ‘waste heat recovery’ has been written to contribute for the ASME Power Plant Cooling Specification/Decision-making Guide to be published in 2013. This paper informs tentative contents for the section on how to beneficially apply waste heat and water recovery technology into power plants. This paper describes waste heat recovery in power plant, current/innovative technologies, specifications, case study, combined cycle, thermal benefits, effects on system efficiency, economic and exergetic benefits. It also outlines water recovery technologies, benefits in fresh water consumptions, reducing acids emission, additional cooling effects, economic analysis and critical considerations.

Head loss through porous dikes

1988 ◽  
Vol 15 (5) ◽  
pp. 766-775
Author(s):  
Subhash C. Jain ◽  
Forrest M. , Jr. ◽  
Tim H. Lee
Keyword(s):  
Reynolds Number ◽  
Porous Media ◽  
Material Properties ◽  
Power Plants ◽  
Heat Dissipation ◽  
Cooling Water ◽  
Head Loss ◽  
Scale Model ◽  
Flow Through ◽  
Full Scale Tests

Porous dikes have been proposed for use in blocking access of fish to cooling water intakes in power plants using large cooling ponds for heat dissipation. Flow through such dikes is neither of the Darcy type nor quadratic, the friction factor depending on both the Reynolds number and material properties. Full-scale tests of the dike material proposed for the LaSalle County power plant confirmed the material-property and Reynolds-number dependencies reported in the literature and permitted calibration of the head-loss parameters for the prototype material under two placement configurations. Limited tests on dike clogging by surface debris permitted quantification of the additional head loss which clogging could cause. Key words: porous media, cooling ponds, dikes, scale model tests.

scholarly journals THE WAVE PRESSING PLATE FOR PROTECTING COOLING WATERWAYS OF COASTAL POWER PLANTS

1984 ◽  
Vol 1 (19) ◽  
pp. 194 ◽  
Author(s):  
S.C. Chow ◽  
Frederick L.W. Tang ◽  
H.H. Hwung
Keyword(s):  
Power Plant ◽  
Water Surface ◽  
Nuclear Power ◽  
Power Plants ◽  
Wave Motion ◽  
Cooling Water ◽  
Northern Coast ◽  
Horizontal Plate ◽  
Hydraulics Laboratory ◽  
Power Plant Cooling

A horizontal plate laid on water surface to reduce the wave motion is proved to be effective theoretically and verified by model tests done at Tainan Hydraulics Laboratory. This principle has been put into practice on the northern coast of Taiwan for protecting a nuclear power plant cooling water intake against intruding waves. The design and construction of wave prevention works of such type are described succinctly in the paper. Also the effect of wave diminishing has been affirmed by measuring the respective waves heights outside and inside of the wave pressing plate.

scholarly journals Comparison between OCl−-Injection and In Situ Electrochlorination in the Formation of Chlorate and Perchlorate in Seawater

2019 ◽  
Vol 9 (2) ◽  
pp. 229 ◽  
Author(s):  
Jongchan Yi ◽  
Yongtae Ahn ◽  
Moongi Hong ◽  
Gi-Hyeon Kim ◽  
Nisha Shabnam ◽  
...  
Keyword(s):  
Reaction Time ◽  
Electrode Material ◽  
Power Plants ◽  
Cooling System ◽  
Cooling Water ◽  
Injection System ◽  
No Production ◽  
Cooling Systems ◽  
Environmentally Friendly Method

To prevent biofouling from occurring in the cooling systems of coastal power plants, chlorine is often added to the cooling water. In this study, we have evaluated the fate of the total residual oxidants and the formation of inorganic chlorination byproducts including ClO3− and ClO4− during in situ electrochlorination with seawater. Then, the results were compared with those during direct OCl−-injection to seawater. The in situ electrochlorination method based on Ti/RuO2 electrodes produced much less ClO3−, while a similar level of total residual oxidants could be achieved with a reaction time of 5 min. Moreover, no ClO4− was observed, while the direct OCl−-injection system could still result in the production of ClO4−. The less or no production of ClO3− or ClO4− by the electrochlorination of seawater was mainly attributed to two reasons. First, during the electrolysis, the less amount of OCl− is available for ClO3− formation. Secondly, the formation of ClO3− or ClO4− is affected by the electrode material. In other words, if the electrode material is carefully chosen, the production of harmful reaction byproducts can be prevented or minimized. In short, based on the results from our study, electrochlorination technology proves to be a marine environmentally friendly method for controlling biofouling in the pipes of the cooling system in a coastal power plant.

Thermal Effects of Nuclear Power Stations

1974 ◽  
Vol 9 (1) ◽  
pp. 188-195
Author(s):  
G. Bethlendy
Keyword(s):  
Thermal Effects ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Sea Water ◽  
Waste Heat ◽  
Thermal Power ◽  
Cooling Water ◽  
District Heating ◽  
Before And After

Abstract Even with the latest technology, more than 60% of the heat produced by any thermal engine - whether the fuel is coal, oil, gas or uranium - must be taken back into the environment by cooling water or exhaust gas. For economical reasons, the usual means of disposing of the “waste” heat from a thermal-power plant is to pump river, lake or sea water through the parts of the plant concerned. Nuclear power plants use their heat as efficiently as older thermal plants, 30–33%. Modern thermal plants, however work with as high as 40% efficiency, and release about 10–13% of their total fuel-heat into the air through the stack. As a result of the combination of all these factors, nuclear power plants release about 68–70% of total input heat into the cooling water. In practice this means that the plant must be able to draw upon a source of cooling water which is large enough, which flows quickly or is cold enough not to be seriously effected by the return of warmed-up water from the power station. Where this is not possible, it may be necessary to build relatively expensive cooling ponds and/or towers so that the heat is also released to the air rather than only to a local body of water. The thermal effects could be detrimental or beneficial depending on the utilization of the water body. At the present time the utilities are aware of these problems and very extensive aquatic studies are being made before and after the construction of the plants. Some beneficial uses of waste heat are being sought via research and demonstration projects (e.g. in agriculture, aquaculture, district heating, etc.).

Modeling Power Generation Water Usage

2015 ◽  
Author(s):  
Jaron J. Peck ◽  
Amanda D. Smith
Keyword(s):  
Power Generation ◽  
Thermoelectric Power ◽  
Power Output ◽  
Power Plants ◽  
Cooling Tower ◽  
Cooling Water ◽  
Rankine Cycle ◽  
Closed Circuit ◽  
Cooling Systems ◽  
Temperature Range

Climate change can have a large effect on thermoelectric power generation. Typical thermoelectric power plants rely on water to cool steam in the condenser in order to produce electricity. Increasing global temperatures can increase average water temperatures as well as decrease the amount of water available for cooling due to evaporation. It is important to know how these parameters can affect power generation and efficiency of power systems, especially when assessing the water needs of a plant for a desired power output and whether a site can fulfill those needs. This paper explains the development of a model that shows how power and efficiency are affected due to changing water temperature and water availability for plants operating on a Rankine cycle. Both a general model of the simple Rankine cycle as well as modifications for regeneration and feedwater heating are presented. Power plants are analyzed for two different types of cooling systems: once-through cooling and closed circuit cooling with a cooling tower. Generally, rising temperatures in cooling water have been found to lower power generation and efficiency. Here, we present a method for quantifying power output and efficiency reductions due to changes in cooling water flow rates or water temperatures. Using specified plant parameters, such as boiler temperature and pressure, power and efficiency are modeled over a 5°C temperature range of inlet cooling water. It was found that over this temperature range, power decrease ranged from 2–3.5% for once through cooling systems, depending on the power system, and 0.7% for plants with closed circuit cooling. This shows that once-through systems are more vulnerable to changing temperatures than cooling tower systems. The model is also applied to Carbon Plant, a coal fired power plant in Utah that withdraws water from the Price River, to show how power and efficiency change as the temperature of the water changes using USGS data obtained for the Price River. The model can be applied to other thermoelectric power stations, whether actual or proposed, to investigate the effects of water conditions on projected power output and plant efficiency.

Application of Optimal Preview Control to Power Plant Cooling Systems

1979 ◽  
Vol 101 (2) ◽  
pp. 162-171 ◽  
Author(s):  
D. R. Gunewardana ◽  
M. Tomizuka ◽  
D. M. Auslander
Keyword(s):  
Power Plants ◽  
Cooling Tower ◽  
Dynamic Control ◽  
Cooling Water ◽  
Control Policy ◽  
Substantial Improvement ◽  
Ambient Conditions ◽  
Preview Control ◽  
Cooling Systems ◽  
Control Scheme

This paper deals with the application of dynamic control to cooling systems of power plants. The operation of heat dispersal systems with control can result in a saving of power and cooling water. The performance of all cooling systems depends, mainly, upon the ambient conditions and the heat load to be dissipated. Hence, a control scheme that makes use of information obtained by previewing the weather and load conditions, i.e., preview control, is ideally suited for this problem. An iterative procedure is presented for determining the optimal preview control policy for a dynamical system whose dynamics vary depending upon the mode of operation that the controller selects. The algorithm is applied to two types of cooling systems: one consisting of a spray pond and a natural draft wet cooling tower, and the other consisting of a spray pond and a dry cooling tower. The preview control scheme is shown to be a substantial improvement over the uncontrolled case.

scholarly journals Feasibility Analysis of a Membrane Desorber Powered by Thermal Solar Energy for Absorption Cooling Systems

2020 ◽  
Vol 10 (3) ◽  
pp. 1110 ◽  
Author(s):  
Jonathan Ibarra-Bahena ◽  
Eduardo Venegas-Reyes ◽  
Yuridiana R. Galindo-Luna ◽  
Wilfrido Rivera ◽  
Rosenberg J. Romero ◽  
...  
Keyword(s):  
Experimental Data ◽  
Water Vapor ◽  
Solar System ◽  
Waste Heat ◽  
Cooling Water ◽  
Solution Temperature ◽  
Hydrophobic Membrane ◽  
Cooling Systems ◽  
Libr Solution ◽  
Absorption Cooling

In absorption cooling systems, the desorber is a component that separates the refrigerant fluid from the liquid working mixture, most commonly completed by boiling separation; however, the operation temperature of boiling desorbers is generally higher than the low-enthalpy energy, such as solar, geothermal, or waste heat. In this study, we used a hydrophobic membrane desorber to separate water vapor from an aqueous LiBr solution. Influencing factors, such as the H2O/LiBr solution and cooling water temperatures, were tested and analyzed. With the experimental data, a solar collector system was simulated on a larger scale, considering a 1 m2 membrane. The membrane desorber evaluation shows that the desorption rate of water vapor increased as the LiBr solution temperature increased and the cooling water temperature decreased. Based on the experimental data from the membrane desorber/condenser, a theoretical heat load was calculated to size a solar system. Meteorological data from Emiliano Zapata in Mexico were considered. According to the numerical result, nine solar collectors with a total area of 37.4 m2 provide a solar fraction of 0.797. The membrane desorber/condenser coupled to the solar system can provide an average of 16.8 kg/day of refrigerant fluid that can be used to produce a cooling effect in an absorption refrigerant system.

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