scholarly journals Improving the waste utilisation efficiency of combined heat and power plants by increasing the performance of dry-ash output units

2021 ◽  
Vol 25 (2) ◽  
pp. 207-219
Author(s):  
A. D. Mekhryakov ◽  
A. N. Kudryashov ◽  
T. V. Koval

The study aims to improve the efficiency of waste utilisation from the coal-fired power industry based on an analysis of the dry-ash output unit operating at the Novo-Irkutsk Combined Heat and Power Plant, JSC “Irkutskenergo”. The unit was tested under various operating conditions of steam generating blocks following the standard methods adopted at the enterprise. The tests showed that the station steam generating block No. 3 (with a steam load of 409.2 t/h and an electrostatic precipitator efficiency of 90.46%) provided an ash supply efficiency of 7.10 t/h. When the ash is supplied from the steam generating block No. 4, operating at a steam load of 421.8 t/h and an electrostatic precipitator efficiency of 94.72%, the ash supply efficiency amounts to 9.19 t/h. Under the simultaneous operation of the steam generating blocks No. 3 and 4 at a steam load of 397.6 and 380.7 t/h, respectively, and an electrostatic precipitator efficiency of 90.46 and 94.72%, respectively, the unit efficiency was 14.23 t/h. As a result, limitations in the unit operation were identified. Thus, the airspeed in the pneumatic ash pipeline during ash transporting was 8.0-8.5 m/s, which facilitated the operation of the dry-ash output unit in a pulsed cycle. It was, therefore, recommended to increase the airspeed by accelerating the flow rate through the jet pump or by using a smaller diameter pipe. The conducted analysis showed that the efficiency of the dry-ash output unit depends mainly on the steam capacity of steam generating blocks, as well as on the flue gas cleaning efficiency in the steam generator electrostatic precipitators. The obtained results were used to determine the technical state, efficiency and reliability of the dry-ash output unit of the Novo-Irkutsk Combined Heat and Power Plant.

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1862
Author(s):  
Tammo Zobel ◽  
Christian Schürch ◽  
Konstantinos Boulouchos ◽  
Christopher Onder

Decentralized power generation by combined heat and power plants becomes increasingly popular as a measure to advance the energy transition. In this context, a substantial advantage of small combined heat and power plants is based on the relatively low pollutant emissions. However, a large proportion of the pollutant emissions is produced during a cold-start. This fact is not reflected in governmental and institutional emission guidelines, as these strongly focus on the emission levels under steady-state conditions. This study analyzes the spark advance, the reference air/fuel ratio and an electrically heated catalyst in terms of their potential to reduce the cold-start emissions of a micro combined heat and power plant which uses a natural gas fueled reciprocating internal combustion engine as prime mover and a three-way catalytic converter as aftertreatment system. Based on these measures, control approaches were developed that account for the specific operating conditions of the class of small combined heat and power plants, e.g., full-load operation and flexible, demand-driven runtimes. The experimental data demonstrates that even solutions with marginal adaptation/integration effort can reduce cold-start emissions to a great extent.


Author(s):  
G. Hariharan ◽  
B. Kosanovic

The ability of modern power plant data acquisition systems to provide a continuous real-time data feed can be exploited to carry out interesting research studies. In the first part of this study, real-time data from a power plant is used to carry out a comprehensive heat balance calculation. The calculation involves application of the first law of thermodynamics to each powerhouse component. Stoichiometric combustion principles are applied to calculate emissions from fossil fuel consuming components. Exergy analysis is carried out for all components by the combined application of the first and second laws of thermodynamics. In the second part of this study, techniques from the field of System Identification and Linear Programming are brought together in finding thermoeconomically optimum plant operating conditions one step ahead in time. This is done by first using autoregressive models to make short-term predictions of plant inputs and outputs. Then, parameter estimation using recursive least squares is used to determine the relations between the predicted inputs and outputs. The estimated parameters are used in setting up a linear programming problem which is solved using the simplex method. The end result is knowledge of thermoeconomically optimum plant inputs and outputs one step ahead in time.


Author(s):  
Erik Rosado Tamariz ◽  
Norberto Pe´rez Rodri´guez ◽  
Rafael Garci´a Illescas

In order to evaluate the performance of new turbo gas power plants for putting in commercial operation, it was necessary to supervise, test and, if so the case, to approve the works of commissioning, operational and acceptance of all equipments and systems that constitute the power plant. All this was done with the aim of guaranteeing the satisfactory operation of these elements to accomplish the function for which they were developed. These activities were conducted at the request of the customer to confirm and observe that the evidence of the tests was carried out according to the specifications and international regulations. The putting into commercial operation activities were done in collaboration with the supplier and manufacturer of equipment, the client and the institution responsible for certification and approval of the plant. All this in a logical and chronological order for the sequence of commissioning tests, operation and acceptance. Commissioning tests were carried out on-site at normal operating conditions, according to the design and operation needs of each power plant of a group of 14. Once the commissioning tests were completely executed and in a satisfactory manner, operational tests of the plants were developed. This was done by considering that they must operate reliable, stable, safe and automatically, satisfying at least, one hundred hours of continuous operation at full load. After evaluating the operational capacity of the machine, it was necessary to determinate the quality of the plant by carrying out a performance test. Finally, it was verified if every unit fulfills the technical requirements established in terms of heat capacity of the machine, noise levels and emissions. As a result of this process, it is guaranteed to the customer that the turbo gas power plants, their systems and equipments, satisfy the requirements, specifications and conditions in agreement with the supplier and manufacturers referring to the putting into commercial operation of the plant.


Author(s):  
Cesar Celis ◽  
Sergio Peralta ◽  
Walter Galarza

Abstract The influence of different power augmentation techniques used in gas turbines on the performance of simple cycle type power plants is assessed in this work. A computational model and tool realistically describing the performance of a typical simple cycle type power plant at design and off-design point conditions is initially developed. This tool is complemented with different models of power augmentation technologies. Finally, the whole model including both power plant and power augmentation techniques is used to analyze a case study involving a particular power plant in Peru. The results from the simulations of the specific power plant indicate that power output can be increased through all the evaluated power augmentation technologies. These results show indeed that technologies based on absorption refrigeration systems produce the largest gains in terms of power output (7.1%) and thermal efficiency (0.7%). Such results confirm the suitability of these systems for simple cycle type power plant configurations operating under hot and humid operating conditions as those accounted for here. From an economic perspective, considering the net present value as the key parameter defining the feasibility of a project in this category, power augmentation techniques based on absorption cooling systems result also the most suitable ones for the studied power plant. Power augmentation techniques environmental implications are also quantified in terms of CO2 emissions.


2018 ◽  
Vol 41 ◽  
pp. 02011 ◽  
Author(s):  
Olesya Aksenova ◽  
Evgenia Nikolaeva

The article seeks to examine the efficiency of applying means of mathematical processing and computer modeling of the work processes of gas cleaning facilities of power plants to optimize the process of planning and designing of future power plant in operation. A way of solution of the gas outbursts cleaning problem at the stage of designing measures for the development of waste processing systems through mathematical processing of expected volumes of gas outbursts and computer simulation of individual pieces of equipment and working areas as a whole is offered. The authors present the results of the processing of the projected technological processes and the gas outbursts cleaning facilities in terms of E-networks and using mathematical processing in the application Simulink, which allows to build a model of the device and to carry out calculations on the screen using the library of building blocks. A 3D model of the gas cleaning facilities, which allows to visualize the technological process and to compare it with theoretical calculations at the design stage of the future power plant and, if necessary, make changes to the project, has been created by means of computer modeling.


Author(s):  
P. S. Neporozhnii ◽  
A. K. Kirsh

This paper describes the operating conditions which form the basis for determining the various types of feed pump units needed to equip the main power plant equipment in the U.S.S.R. The principles upon which the feed pump groups are selected, according to the type of equipment installed in different power plants, are considered. The system diagrams and design features of the feed pumps are presented, together with descriptions of how they are driven.


Author(s):  
R. Chacartegui ◽  
D. Sa´nchez ◽  
J. A. Becerra ◽  
A. Mun˜oz ◽  
T. Sa´nchez

In this work, a tool to predict the performance of fossil fuel steam power plants under variable operating conditions or under maintenance operations has been developed. This tool is based on the Spencer-Cotton-Cannon method for large steam turbine generator units. The tool has been validated by comparing the predicted results at different loads with real operating data of a 565 MW steam power plant, located in Southern Spain. The results obtained from the model show a good agreement with most of the power plant parameters. The simulation tool has been then used to predict the performance of a steam power plant in different operating conditions such as variable terminal temperature difference or drain cooler approach of the feed-water heaters, or under maintenance conditions like a feed-water heater out of service.


2020 ◽  
pp. 245-250
Author(s):  
А.В. Балакин ◽  
А.Н. Дядик ◽  
А.С. Кармазин ◽  
М.В. Ларионов ◽  
С.Н. Сурин

В статье представлена упрощенная имитационная модель, описывающая работу топливного процессора в составе воздухонезависимой энергетической установки. Рассмотрено блочное моделирование отдельных составляющих ВНЭУ, в частности, высокотемпературного реактора, блока очистки газа от серы и сажи, первого и второго блоков конверсии, сепаратора и регулирующего клапана. Имитационные модели отдельных элементов ВНЭУ позволяют рассчитывать динамические характеристики энергоустановки и создавать алгоритмы управления клапанами подачи водорода в переходных режимах. Теоретические зависимости для определения массовых расходов реагентов, температур и давлений приведены для идеальных газов с целью представления в среде LabVIEW с учетом полученных экспериментальных данных для проведения расчета маневров по регулированию давления на заданных режимах работы ВНЭУ при различных условиях ее работы. The article presents a simplified simulation model that describes the operation of the fuel processor as part of an air-independent power plant. Block modeling of the individual components of an air-independent power plant, in particular, a high-temperature reactor, a unit for cleaning gas from sulfur and soot, the first and second conversion units, a separator, and a control valve, is considered. Simulation models of individual elements of an air-independent power plant allow you to calculate the dynamic characteristics of a power plant and create algorithms for controlling hydrogen supply valves in transient conditions. Theoretical dependencies for determining the mass flow rates of reagents, temperatures and pressures are given for ideal gases for the purpose of presentation in the LabVIEW environment, taking into account the obtained experimental data for the calculation of maneuvers for regulating pressure at specified operating modes of an air-independent power plant under various operating conditions. The results of the work are described extremely accurately and informatively. The main theoretical and experimental results, actual data, discovered relationships and regularities are presented.


Author(s):  
Mikhail Balzannikov

The article describes run-of-the-river hydroelectric power plants. The authors specify the importance of performing technical and economic calculations in justifying the large-sized units of the water-supplying channel of a run-of-the-river hydroelectric power plant: turbine pits and suction (discharge) pipes. The study shows that the amount of construction work and the total cost of building a hydroelectric power plant depend on the size of these water supply units. The research objective is to analyze the validity of establishing the main dimensions of the suction pipes for modern technical and economic conditions. The researchers use the discounted income method. The calculations are performed for a hydroelectric power plant with an elbow suction pipe. The analysis of how the operating conditions of a hydroelectric power plant influence the savings of construction resources is carried out. The analysis shows that saving construction resources by reducing the length of the suction pipe is justified if the hydroelectric power plamt is designed to work only at peak power loads. For hydroelectric power plants operating at semi-peak or base power loads, the additional construction costs would be appropriate if leading to the decrease in pressure loss and to the increase in electricity generation.


2020 ◽  
Author(s):  
◽  
Romāns Oļekšijs

Change of market principles and European Union environmental targets leads to more cycling operations of combined cycle units, which used to operate in baseload regime. Due to generation imbalanced allocation, which mainly provoked by intermitting generation, power network becomes less stable. As a result, new requirements for generator connection in Europe were developed, challenging existing power plants to fulfill them. All this leads to higher operational costs of combined heat and power plants and solutions must be found to reduce costs and/or increase revenue. Cycling operation negative impact on power plant thermal equipment is well studied. This Doctoral Thesis reviews the cycling operation impact on combined heat and power plant main electrical equipment and provides empirical formulas to evaluate reliability for different operation scenarios. Solutions for power plant modernisations to fulfill new requirements and provide ancillary services are analyzed. Possible costs of ancillary service provision from combined heat and power plants as well as sites connected to transmission system are evaluated, providing information for further calculations. Detailed methodology of solar generated energy applicability for self-consumption needs was developed, which allows to choose the right power of installation to make the fastest payback time. A battery storage optimization methodology was developed to reduce self-consumption costs of power plant interacting with the solar generation or operating separately. The methodology for combined heat and power plant operation planning enhancement was developed, which use gain from ancillary service provision to move startup’s back in time or shutdowns further in future to provide highest revenue. Methodology also allows to use additional profit to grant lowest number of startup’s per year. Results of both approaches are used to make incident rate calculations by developed empirical formulas, which allow to choose optimal strategy for power plant operation. Obtained formulas can be easily used for most combined heat and power plants. Developed methodologies can be used to optimize the self-consumption of any applications. Methodology for power plant operation planning enhancement is applicable to various scenarios. All developed methodologies were tested on historical data. The results of analysis of ancillary service provision remuneration impact on combined heat and power plant main electrical equipment incident rate and possible income should lead to new researches in this area.


Sign in / Sign up

Export Citation Format

Share Document