scholarly journals Errors in Boiler Efficiency Standards

2009 ◽  
Author(s):  
Fred D. Lang
Keyword(s):  
Performance Monitoring ◽  
Calorific Value ◽  
Carbon Taxes ◽  
Steam Generators ◽  
Fuel Feed ◽  
Fuel Flow ◽  
Boiler Efficiency ◽  
Financial Consequences ◽  
Contractual Obligations ◽  
Industrial Standards

This paper presents both criticism and suggested changes to boiler efficiency standards associated with fossil-fired steam generators. These standards include the widely used ASME PTC 4.1, PTC 4 and DIN 1942, and others. The chief criticism is inconsistent application of thermodynamic principles. Specifically, conceptual errors are made with application of reference temperatures and the treatment of shaft powers. When using computed fuel flow as a touchstone, it becomes obvious that arbitrary use of reference temperatures and/or use of capricious energy credits cannot dictate a system’s computed fuel flow. Efficiency, calorific value and fuel flow must have fixed definitions concomitant with a system’s useful energy flow. Thermodynamics is not an arbitrary discipline, the computed fuel needs of a system must describe the actual. Boiler efficiency requires the same treatment, as an absolute value, as actual fuel feed and emission flow. Boiler efficiencies and associated calorific values have obvious standing when judging contractual obligations, for thermal performance monitoring, and for confirming carbon emissions. Note that a 0.5 to 1% change in efficiency may well have significant financial consequences when testing a new unit, or the on-going costs associated with fuel and carbon taxes. This paper demonstrates that errors greater than 2% are entirely possible if following the current standards. This paper appeals to the resolution of efficiency at the 0.1% level. The power plant engineer is encouraged to read the Introduction and Summary & Recommendations sections while the thermodynamicist is requested to throughly review and critique the mid-sections. The author hopes such reviews will advocate for improvement of these important industrial standards.

Flight performance monitoring with optimal filtering applications

2019 ◽  
Vol 124 (1272) ◽  
pp. 170-188
Author(s):  
V. A. Deo ◽  
F. Silvestre ◽  
M. Morales
Keyword(s):  
Kalman Filter ◽  
Performance Monitoring ◽  
The Body ◽  
Flight Performance ◽  
Performance Parameters ◽  
Sideslip Angle ◽  
Fuel Flow ◽  
Aircraft Performance ◽  
Lift And Drag

ABSTRACTThis work presents an alternative methodology for monitoring flight performance during airline operations using the available inboard instrumentation system. This method tries to reduce the disadvantages of the traditional specific range monitoring technique where instrumentation noise and cruise stabilisation conditions affect the quality of the performance monitoring results. The proposed method consists of using an unscented Kalman filter for aircraft performance identification using Newton’s flight dynamic equations in the body X, Y and Z axis. The use of the filtering technique reduces the effect of instrumentation and process noise, enhancing the reliability of the performance results. Besides the better quality of the monitoring process, using the proposed technique, additional results that are not possible to predict with the specific range method are identified during the filtering process. An example of these possible filtered results that show the advantages of this proposed methodology are the aircraft fuel flow offsets, as predicted in the specific range method, but also other important aircraft performance parameters as the aircraft lift and drag coefficients (CL and CD), sideslip angle (β) and wind speeds, giving the operator a deeper understanding of its aircraft operational status and the possibility to link the operational monitoring results to aircraft maintenance scheduling. This work brings a cruise stabilisation example where the selected performance monitoring parameters such as fuel flow factors, lift and drag bias, winds and sideslip angle are identified using only the inboard instrumentation such as the GPS/inertial sensors, a calibrated anemometric system and the angle-of-attack vanes relating each flight condition to a specific aircraft performance monitoring result. The results show that the proposed method captures the performance parameters by the use of the Kalman filter without the need of a strict stabilisation phase as it is recommended in the traditional specific range method, giving operators better flexibility when analysing and monitoring fleet performance.

Monitoring and Improving Coal-Fired Power Plants Using the Input/Loss Method: Part IV

2004 ◽  
Author(s):  
Fred D. Lang
Keyword(s):  
Error Analysis ◽  
Power Plants ◽  
Heat Rate ◽  
Calorific Value ◽  
Mineral Matter ◽  
Fuel Flow ◽  
Direct Measurements ◽  
On Line ◽  
Plant Data ◽  
Loss Method

The Input/Loss Method is a unique process which allows for complete thermal understanding of a power plant through explicit determinations of fuel chemistry including fuel water and mineral matter, fuel heating (calorific) value, As-Fired fuel flow, effluent flow, boiler efficiency and system heat rate. Input consists of routine plant data and any parameter which effects system stoichiometrics, including: Stack CO2, Boiler or Stack O2, and, generally, Stack H2O. It is intended for on-line monitoring of coal-fired systems; effluent flow is not measured, plant indicated fuel flow is typically used only for comparison to the computed. The base technology of the Input/Loss Method was documented in companion ASME papers: Parts I, II and III (IJPGC 1998-Pwr-33, IJPGC 1999-Pwr-34 and IJPGC 2000-15079/CD). The Input/Loss Method is protected by US and foreign patents (1994–2004). This Part IV presents details of the Method’s ability to correct any data which effects system stoichiometrics, data obtained either by direct measurements or by assumptions, using multi-dimensional minimization techniques. This is termed the Error Analysis feature of the Input/Loss Method. Addressing errors in combustion effluent measurements is of critical importance for any practical on-line monitoring of a coal-fired unit in which fuel chemistry is being computed. It is based, in part, on an “L Factor” which has been proven to be remarkably constant for a given source of coal; and, indeed, even constant for entire Ranks. The Error Analysis feature assures that every computed fuel chemistry is the most applicable for a given set of system stoichiometrics and effluents. In addition, this paper presents comparisons of computed heating values to grab samples obtained from train deliveries. Such comparisons would not be possible without the Error Analysis.

scholarly journals Fuel Used Analysis on Boiler Efficiency Variations and Water Intake Temperature Affected by Palm Oil Varieties

2021 ◽  
Vol 4 (1) ◽  
pp. 94-105
Author(s):  
Zulham Effendi ◽  
Siti Aisyah ◽  
Rionaldo Hastyanda
Keyword(s):  
Water Temperature ◽  
Palm Oil ◽  
Calorific Value ◽  
Feed Water ◽  
Fuel Mass ◽  
Fuel Savings ◽  
A Value ◽  
Boiler Efficiency ◽  
Intake Water ◽  
Additional Fuel

Several factors that affect the use of fuel in boilers are combustion efficiency, quality of feed water management, calorific value, and the potential for available fuel from oil palm varieties. The purpose of this research is to identify the use of fuel and its potential savings based on variations in boiler efficiency and water temperature that entered the boiler. The materials used in this research are FFB mass balance data and boiler fuel composition. Based on the analysis results, the lowest used fuel mass and the highest fuel savings are found in the DxPLangkat variety with an intake water temperature of 105o C and 80% boiler efficiency. The use of fuel is 4,231 kg/hour with shell savings of 967 kg/hour with a value of IDR 725,701. Fiber savings was 487 kg/hour with a value of IDR 121,751.The highest used fuel mass and the lowest fuel savings were found in the Yangambi derivative variety with an intake water temperature of 85o C and 60% boiler efficiency.The fuel consumption is 5,830 kg/hour with shell savings totalling -380 kg/hour. There is no fiber analysis because it is used up hence additional fuel is needed. Additional fuel can be done by asking for other palm oil mill units or buying. If they buy a shell with a requirement of 380 kg/hour, the funds required are IDR 284,939.

scholarly journals Exergy efficiency analysis of lignite-fired steam generator

2018 ◽  
Vol 22 (5) ◽  
pp. 2087-2101
Author(s):  
Drenusha Krasniqi-Alidema ◽  
Risto Filkoski ◽  
Marigona Krasniqi
Keyword(s):  
Steam Generator ◽  
Flue Gas ◽  
Power Plants ◽  
Thermal Power ◽  
Calorific Value ◽  
Feed Water ◽  
Low Grade ◽  
Gas Temperature ◽  
Steam Generators ◽  
Energy And Exergy

The operation of steam generators and thermal power plants is commonly evaluated on a basis of energy analysis. However, the real useful energy loss cannot be completely justified only by the First law of thermodynamics, since it does not differentiate between the quality and amount of energy. The present work aims to give a contribution towards identification of the sources and magnitude of thermodynamic inefficiencies in utility steam generators. The work deals with a parallel analysis of the energy and exergy balances of a coal-fired steam generator that belongs to a 315 MWe power generation unit. The steam generator is de-signed for operation on low grade coal - lignite with net calorific value 6280 to 9211 kJ/kg, in a cycle at 545?C/177.4 bar, with feed water temperature 251?C, combustion air preheated to 272?C and outlet flue gas temperature 160?C. Since the largest exergy dissipation in the thermal power plant cycle occurs in the steam generator, energy, and exergy balances of the furnace and heat exchanging surfaces are established in order to identify the main sources of inefficiency. On a basis of the analysis, optimization of the combustion and heat transfer processes can be achieved through a set of measures, including retrofitting option of lignite pre-drying with flue gas and air preheating with dryer exhaust gases.

scholarly journals Efficiency of an aquatubular boiler from the burning of four cultivars of sugar cane

2020 ◽  
Vol 9 (11) ◽  
pp. e5469119859
Author(s):  
Marcelo Costa Dias ◽  
Antonio Manoel Batista da Silva ◽  
Lúcio Rogério Junior
Keyword(s):  
Sugar Cane ◽  
Energy Production ◽  
Energy Use ◽  
Production Systems ◽  
Direct Method ◽  
Calorific Value ◽  
Production Chain ◽  
South Central ◽  
Boiler Efficiency ◽  
Steam Production

The growing demand for energy from renewable sources increasingly seeks to implement efficient energy production systems. Thus, the objective of this work is to determine the thermal efficiency of an aquatubular boiler that will burn the bagasse from four sugarcane cultivars: SP 80-1816, RB72-454, SP80-3280 and SP81-3250. This efficiency will be determined through the calculation methods: PCI - lower calorific value, PCS - higher calorific value and direct method. These cultivars were planted in the south-central region of Brazil where the largest sugar cane producers in the country are located. The results obtained show the importance of the energy analysis that each cultivar provides for energy cogeneration, as well as the benefits that will directly influence its production chain for controlled management. Among the benefits of controlled management are: maximizing processes and optimizing the energy use of each cultivar. The optimum efficiency of the boiler in energy production in relation to steam production depends on the intrinsic variables of each cultivar, such as bagasse and moisture content. When calculating the boiler efficiency, the SP 80-1816 variety proved to be more advantageous in relation to the others, considering the same characteristics of the production process, planting region, harvest time and the same type of boiler used. Still related to the study, the cultivar SP 80-1816 requires a smaller amount of bagasse in the boiler feed to produce heat, which results in greater energy production considering the same amount of bagasse of the studied varieties.

Modeling and Simulation for Multiple Damage Progression of Tank-to- Engine Fuel Feed System

2020 ◽  
Vol 13 (5) ◽  
pp. 751-757
Author(s):  
Li Wenjuan ◽  
Liu Haiqiang ◽  
Zhang Bo
Keyword(s):  
Modeling And Simulation ◽  
System Analysis ◽  
System Modeling ◽  
Engine Fuel ◽  
Feed System ◽  
Vane Pump ◽  
Fuel Feed ◽  
Remaining Service Life ◽  
Subsequent Investigation ◽  
Fuel Flow

Background: A centrifugal vane pump driven by a three-phase AC motor is a key component for modern equipment. Therefore, its condition directly affects the operating and safety performance of the system. Modeling and simulation are effective methods for the system analysis. Methods: A mathematical model of a Tank-to-Engine Fuel Feed System (T-EFFS) is designed based on its phased-mission behavior and structure redundancy. Both of the damage modes that arise frequently in a given type of system are tracked: the fuel feed pump seal damage due to fatigue and the vane damage due to corrosion. Then, a multiple degradation T-EFFS model is established to simulate the fuel pressure at the system outlet under different damage modes. The morphological spectrum decrement index is used to describe the damage of the system. Results: The results show that the T-EFFS model can describe the phased-mission behavior of the system and meet the requirement of the fuel flow rate for the entire mission profile. Then, the decrease in the fuel pressure of the T-EFFS with the cumulative effects of vane damage and crack growth under different behavior modes is simulated along its life span. Conclusion: This work aims to provide a model and data support for a subsequent investigation. The results can be used to fit the health background curve of the system, predict the performance degradation trend of the system at given life points, and further evaluate its remaining service life.

Use of Multiple Variable Mathematical Method for Effective Condition Monitoring of Gas Turbines

2010 ◽  
Author(s):  
Ezenwa A. Ogbonnaya ◽  
Kombo Theophilus-Johnson
Keyword(s):  
Condition Monitoring ◽  
Gas Turbines ◽  
Performance Monitoring ◽  
Process Equipment ◽  
Fuel Flow ◽  
Port Harcourt ◽  
Periodic Monitoring ◽  
Multiple Variable ◽  
One Year ◽  
Rivers State

All over the globe, gas turbines (GTs) play tremendous role in energy and power generation. Condition monitoring is also being used to obtain early warning of impending equipment failure to prevent costly downtime and damage to process equipment. Several scheduled visits were thus made to AFAM IV, GT 18, TYPE 13D plant located near Port Harcourt, in Rivers State of Nigeria. Continuous and periodic monitoring of the thermodynamics/performance parameters such as temperature, pressure, air pumping capability and fuel flow were carried out. These activities lasted for over a period of one year on hourly basis to examine the state of health of the engine compared with the data taken. The diagnostic method of trend performance monitoring was jointly used with multiple variable mathematical models (MVMMs), because they relate deterioration to consequences. A software code-named “THAPCOM” written in C++ programming language was used proactively monitor the engine based on this MVMMs. The values observed on the third month revealed that ηO was 27.0% and AL was 48MW. A significant variation in the results obtained shows that there is a deviation between the monitored data taken from the console and the reference data in the manufacturer’s manual. These are indications of impending failure or health uncertainty of the engine. This allowed maintenance to be scheduled, or other actions taken to avoid catastrophy.

scholarly journals Analisa Pengaruh Perubahan Beban Output Turbin Terhadap Efisiensi Boiler

2020 ◽  
Vol 3 (2) ◽  
pp. 44
Author(s):  
Jatmiko Edi Siswanto
Keyword(s):  
Calorific Value ◽  
Extraction Process ◽  
Steam Boiler ◽  
Electric Generator ◽  
Oil Processing ◽  
A Value ◽  
Boiler Efficiency ◽  
Boiling Process ◽  
Boiler Operation ◽  
To Come

In palm oil processing companies to become oil, the boiling process is carried out to make it easier for the loose fruit to come from the bunches, to stop the development of free fatty acids and will cause the tbs to soften so the oil extraction process becomes easier. The boiling process requires steam from steam. Steam is obtained by heating a vessel filled with water with fuel. Generally, boilers use liquid, gas and solid fuels. Steam functions as a boiling and electric generator, the company uses a boiler as a steam producer to support the production process. A boiler or steam boiler is a closed vessel used to produce steam through an energy conversion process. To find out the boiler efficiency, a calculation is carried out by taking the parameters needed for boiler operation, from the analysis the highest boiler efficiency results are 83.56% and the lowest is 75.25%, where the heating value with 13% fuel at 1000 Kw load is 83, 56%. And the calorific value with 10% fuel at a load of 750 Kw is smaller with a value of 75.25%.

scholarly journals Performance and boiler efficiency using low-grade coal on 400 MWe coal-fired power plant: case study of Suralaya Power Plant Unit 2

2021 ◽  
Vol 882 (1) ◽  
pp. 012033
Author(s):  
Eko Supriyanto ◽  
Nur Cahyo ◽  
Ruly Sitanggang ◽  
Rasgianti ◽  
Meiri Triani ◽  
...  
Keyword(s):  
Power Plant ◽  
Heat Loss ◽  
Heat Rate ◽  
Calorific Value ◽  
Plant Performance ◽  
Low Grade ◽  
Hydrogen Burning ◽  
Steam Power ◽  
Boiler Efficiency ◽  
Loss Method

Abstract In a coal steam power plant, changes in coal quality significantly affect plant performance, especially in its boiler. A coal-fired power plant with a capacity of 400 MWe had been commissioned using coal with a calorific value of 5,242 kCal/kg. This study aims to determine the effect on unit performance and boiler efficiency due to changes in fuel use with the typical calorific value of 3,520 kCal/kg, 34,17% lower than the initial design. The performance tests were conducted using the heat loss method at loads: 50%, 65%, 75%, and 100%. The test result showed that using low-grade coal reduces boiler efficiency by 6.26%. There were four dominant boiler losses: heat loss due to moisture in dry flue gas, heat loss due to combustible in refuse, heat loss due to moisture in fuel, and heat loss due to hydrogen burning. Furthermore, the gross plant heat rate using low-grade coal was increased from 2,120 kCal/kWh to 2,718 kCal/kWh; however, the electric price becomes cheaper from 1.99 cent-USD/kWh becomes 1.31 cent-USD/kWh.

Dynamic Simulation of the Gravel Bed Combustor-Gas Turbine System

1991 ◽  
Author(s):  
Carl A. Palmer ◽  
Kenneth W. Ragland
Keyword(s):  
Gas Turbine ◽  
Flow Rate ◽  
Control Strategies ◽  
Control Variable ◽  
Load Level ◽  
Primary Control ◽  
Fuel Feed ◽  
Gravel Bed ◽  
Fuel Flow ◽  
Cogeneration System

A novel gravel bed, downdraft, woodchip combustor that directly-fires a gas turbine for use in a cogeneration system has been developed. In this combustor, the fuel burning rate is determined by pressure, temperature, air flow rate, and fuel moisture content, and not by the fuel feed rate. When the gravel bed combustor is connected to a gas turbine system, the operator loses the freedom to directly set the fuel flow rate, which is the primary control variable for conventional gas turbine systems. Other control problems introduced by the gravel bed include a large thermal lag and a sizable pressure drop. This paper presents a computer model that integrates the dynamic characteristics of an actual gas turbine with the characteristics of the gravel bed combustor. The program determines system behavior and helps evaluate possible control strategies. The system is controlled using the CO2 level leaving the gravel bed. The bypass valve setting determines the load level. Both the slow temperature dynamics and quick turbomachinery dynamics must be considered when operating the system.

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