scholarly journals Numerical Modelling and Sensitivity Analysis of Natural Draft Cooling Towers

2018 ◽  
Vol 13 (4) ◽  
Author(s):  
A. Dhorat ◽  
M. A. Al-Obaidi ◽  
I.M. Mujtaba
Keyword(s):  
Sensitivity Analysis ◽  
Power Plants ◽  
Thermal Power ◽  
Operating Cost ◽  
Cooling Towers ◽  
Water Stream ◽  
Distribution Form ◽  
Average Operating ◽  
Saturation Vapour Pressure ◽  
Cost Penalty

Abstract Cooling towers are a relatively inexpensive and consistent method of ejecting heat from several industries such as thermal power plants, refineries, and food processing. In this research, an earlier model from literature was to be validated across three different case studies. Unlike previous models, this model considers the height of the fill as the discretised domain, which produces results that give it in a distribution form along the height of the tower. As there are limitations with the software used (gPROMS) where differential equations with respect to independent variables in the numerator and denominator cannot be solved, a derivative of the saturation vapour pressure with respect to the temperature of the air was presented. Results shown were in agreement with the literature and a parametric sensitivity analysis of the cooling tower design and operating parameters were undertaken. In this work the height of fill, mass flowrates of water and air were studied with respect to sensitivity analysis. Results had shown large variations in the outlet temperatures of the water and air if the mass flows of water and air were significantly reduced. However, upon high values of either variable had shown only small gains in the rejection of heat from the water stream. With respect to the height of the fill, at larger heights of the fill, the outlet water temperature had reduced significantly. From a cost perspective, it was found that a change in the water flowrate had incurred the largest cost penalty with a 1 % increase in flowrate had increased the average operating cost by 1.2 %. In comparison, a change in air flowrate where a 1 % increase in flowrate had yielded an average of 0.4 % increase in operating cost.

DEPENDENCE OF THE NOISE LEVEL OF DRY FAN COOLING TOWERS ON THE POWER OF THERMAL POWER PLANTS

2021 ◽  
Author(s):  
Владимир Борисович Тупов ◽  
Айнур Булатович Мухаметов
Keyword(s):  
Noise Level ◽  
Power Plants ◽  
Thermal Power ◽  
Electrical Power ◽  
Sound Level ◽  
Thermal Power Plants ◽  
Cooling Towers ◽  
Surrounding Area ◽  
Fan Cooling

Сухие вентиляторные градирни тепловых электрических станций могут быть источником превышения санитарных норм на территории станции и в окружающем районе. В статье проведен анализ уровня шума сухих вентиляторных градирен в зависимости от мощности тепловых электрических станций. Получена формула позволяющая определить изменение уровня звука сухих вентиляторных градирен в зависимости от электрической мощности тепловых электрических станций. Dry fan cooling towers of thermal power plants can be a source of exceeding sanitary standards on the territory of the plant and in the surrounding area. The article analyzes the noise level of dry fan cooling towers depending on the power of thermal power plants. A formula has been obtained that makes it possible to determine the change in the sound level of dry fan cooling towers depending on the electrical power of thermal power plants.

scholarly journals Benchmarking of scaling and fouling of reverse osmosis membranes in a power generation plant of paper and board mill: an industrial case of a paper and board mill study

2020 ◽  
Author(s):  
S. Z. J. Zaidi ◽  
A. Shafeeq ◽  
M. Sajjad ◽  
S. Hassan ◽  
M. S. Aslam ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Acid Treatment ◽  
Power Plants ◽  
Saturation Index ◽  
Thermal Power ◽  
Treatment Plant ◽  
Feed Water ◽  
Operational Parameters ◽  
Water Stream ◽  
Reject Water

AbstractThe present study reports the characterization of reverse osmosis (RO) technology at water treatment plant Cogen-2 in paper and Board mills, Pakistan. RO is a commonly used process to obtain de-mineralized water for high-pressure boiler operation in thermal power plants. Scaling and fouling in three-stage RO plants is a major challenge in chemical industry due to the use of raw brackish water in the power plant of paper and board mills. In our study, the feed water quality of RO was changed from soft water to raw water to make it economical. The cleaning frequency was increased three times than normal, which was unsafe for operation and it was required to control scaling and fouling to achieve the desired result. Differential pressures behavior of all stages for 2-month data was observed without acid treatment, and the results of Langelier Saturation Index (LSI) control parameters (temperature, pH, total dissolved solids, calcium hardness, and alkalinity) clearly showed the abnormality. To optimize scaling and fouling of RO, the LSI factor was controlled in total reject water for the next 2 months by acid treatment in feed water. Duration of chemical cleaning and membranes’ life has been extended by fouling and scaling control. Understanding the effect of operational parameters in RO membranes is essential in water process engineering due to its broad applications in drinking water, sanitation, seawater, desalination process, wastewater treatment, and boiler feed water operation. The product flow increased from 18.3 to 19.9 m3/h, and this was due to a decrease in the rejection flow from 8.2 to 6.7 m3/h. The total reject stream pressure also increased from 8.1 to 9 bar. A lower value of LSI of 1.6 is obtained in the reject water stream after the acid treatment.

scholarly journals Active power ouptut optimization for wind farms and thermal units by minimizing the operating cost and emissions

2020 ◽  
Vol 10 (4) ◽  
pp. 3412
Author(s):  
Nazha Cherkaoui ◽  
Abdelaziz Belfqih ◽  
Faissal El Mariami ◽  
Jamal Boukherouaa ◽  
Abdelmajid Berdai
Keyword(s):  
Objective Function ◽  
Power Plants ◽  
Fossil Fuels ◽  
Thermal Power ◽  
Economic Dispatch ◽  
Operating Cost ◽  
Wind Farms ◽  
Optimization Methods ◽  
Optimization Techniques ◽  
Grey Wolf Optimizer

In recent years, many works have been done in order to discuss economic dispatch in which wind farms are installed in electrical grids in addition to conventional power plants. Nevertheless, the emissions caused by fossil fuels have not been considered in most of the studies done before. In fact, thermal power plants produce important quantities of emissions for instance, carbon dioxide (CO2) and sulphur dioxide (SO2) that are harmful to the environment. This paper presents an optimization algorithm with the objective to minimize the emission levels and the production cost. A comparison of the results obtained with different optimization methods leads us to opt for the grey wolf optimizer technique (GWO) to use for solving the proposed objective function. First, the method used to estimate the wind power of a plant is presented. Second, the economic dispatch models for wind and thermal generators are presented followed by the emission dispatch model for the thermal units.Then, the proposed objective function is formulated. Finally, the simulation results obtained by applying the GWO and other known optimization techniques are analysed and compared.

scholarly journals Analysis of the effect of water steam concentration on water drop cooling process efficiency in conditions of water cooling towers of thermal power plants

2018 ◽  
Vol 194 ◽  
pp. 01053 ◽  
Author(s):  
Sergei Shevelev
Keyword(s):  
Power Plants ◽  
Water Drop ◽  
Thermal Power ◽  
Water Evaporation ◽  
Cooling Towers ◽  
Water Cooling ◽  
Evaporative Water ◽  
Water Steam ◽  
Effect Of Water ◽  
Water Drops

Numerical investigation of transient distribution of temperature in water drops cooled in cool blast in conditions typical for high capacity evaporative water cooling towers has been done. Water drops cooling through thermal conductivity and water evaporation has been taken into consideration. It has been proved that the analysis of temperature distribution along the radius of water drop increases reliability of evaluation results of average temperature of water drops when they are cooled. Effect of water steam concentration in steam-gas mixture layer surrounding a water drop on water cooling towers efficiency has been evaluated.

Development of Wet-Bulb-Temperatures in Germany with special regard to conventional thermal Power Plants using Wet Cooling Towers

2011 ◽  
Vol 20 (6) ◽  
pp. 601-614 ◽  
Author(s):  
Valentin Aich ◽  
Ulrike Strauch ◽  
Kevin Sieck ◽  
Dirk Leyens ◽  
Daniela Jacob ◽  
...  
Keyword(s):  
Power Plants ◽  
Thermal Power ◽  
Thermal Power Plants ◽  
Cooling Towers ◽  
Special Regard

A Simplified Model for Predicting Natural Draft Wet Cooling Tower Performance of Large Steam Power Plants

2020 ◽  
Author(s):  
Stefan aus der Wiesche
Keyword(s):  
Power Plant ◽  
Steam Turbine ◽  
Power Plants ◽  
Cooling Tower ◽  
Thermal Power ◽  
Model Parameters ◽  
Zone Model ◽  
Present Calculation ◽  
Cooling Towers ◽  
Natural Draft

Abstract Flexible plant operation and rapid load changes become major issues for steam turbine operation. In thermal power plants, the steam turbine performance is closely related to the condenser, and an accurate prediction of coolant temperature as function of changing weather conditions is necessary in order to optimize power plant fleet operation. In this contribution, a one-dimensional model for simulating the performance of large natural draft wet cooling towers is presented. The evaporation zone model rests on the evaporative cooling theory developed by Merkel and Poppe. The off-design behavior of the cooling tower, that is relevant to part load performance, is modeled by an empirical power-law approach. A user-friendly method is presented in order to identify required model parameters by means of already available power plant data. The simulation tool can be employed easily for existing power plants for which the original cooling tower design and construction data lost their validity. The outcome of the present calculation method is successfully compared with field data from representative cooling towers at Middle-European sites.

scholarly journals Application of BARON Solver for Solution of Cost Based Unit Commitment Problem

2020 ◽  
Vol 12 (4) ◽  
pp. 807-827
Author(s):  
Vineet Kumar ◽  
◽  
R Naresh ◽  
Keyword(s):  
Power Plants ◽  
Unit Commitment ◽  
Thermal Power ◽  
Operating Cost ◽  
Optimal Solution ◽  
Ramp Rate ◽  
Unit Commitment Problem ◽  
Commitment Problem ◽  
Ramp Rate Limits ◽  
Algebraic Modelling

This paper presents the solution to cost-based unit commitment (CBUC) problem with and without ramp rate limits of thermal power plants using general algebraic modelling system (GAMS) with BARON solver. The BARON solver in GAMS environment takes care of different units and system constraints to find an optimal solution. To validate the effectiveness of the proposed GAMS solution, simulations have been performed on six different systems consisting of 10-units, 20-units, 40-units, 60-units, 80-units and 100-units, respectively. The analysis also includes the valve-point loading along with the ramp rate limits of thermal units. Results obtained with BARON solver in GAMS have been compared with other approaches available in literature. Comparative analysis shows that the performance of GAMS is better as compared to other existing techniques in terms of operating cost obtained and satisfaction level of constraints.

A Review on Utilization of Fly- Ash and Pond-Ash as a Partial Replacement of Cement in Concrete Mix Design

2018 ◽  
pp. 413-418
Author(s):  
Harshkumar Patel ◽  
Yogesh Patel
Keyword(s):  
Fly Ash ◽  
Electricity Generation ◽  
Power Plants ◽  
Renewable Energy Sources ◽  
Thermal Power ◽  
Strength Test ◽  
Partial Replacement ◽  
Pond Ash ◽  
Research Activities ◽  
Ash Disposal

Now-a-days energy planners are aiming to increase the use of renewable energy sources and nuclear to meet the electricity generation. But till now coal-based power plants are the major source of electricity generation. Disadvantages of coal-based thermal power plants is disposal problem of fly ash and pond ash. It was earlier considered as a total waste and environmental hazard thus its use was limited, but now its useful properties have been known as raw material for various application in construction field. Fly ash from the thermal plants is available in large quantities in fine and coarse form. Fine fly ash is used in construction industry in some amount and coarse fly ash is subsequently disposed over land in slurry forms. In India around 180 MT fly is produced and only around 45% of that is being utilized in different sectors. Balance fly ash is being disposed over land. It needs one acre of land for ash disposal to produce 1MW electricity from coal. Fly ash and pond ash utilization helps to reduce the consumption of natural resources. The fly ash became available in coal based thermal power station in the year 1930 in USA. For its gainful utilization, scientist started research activities and in the year 1937, R.E. Davis and his associates at university of California published research details on use of fly ash in cement concrete. This research had laid foundation for its specification, testing & usages. This study reports the potential use of pond-ash and fly-ash as cement in concrete mixes. In this present study of concrete produced using fly ash, pond ash and OPC 53 grade will be carried. An attempt will be made to investigate characteristics of OPC concrete with combined fly ash and pond ash mixed concrete for Compressive Strength test, Split Tensile Strength test, Flexural Strength test and Durability tests. This paper deals with the review of literature for fly-ash and pond-ash as partial replacement of cement in concrete.

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