ASMEPTC4锅炉性能试验规程BoilerEfficiency

2019 Babcock Power Inc.  All Rights Reserved 1 Riley Power    Babcock Power Environmental    Babcock Power Services    Boiler Tube Company of America    Vogt Power Thermal Engineering International (USA) Inc.    TEiC Construction Services    TEiC Heat Exchanger Services    Struthers Wells  ASME PTC 4 Boiler Efficiency 锅炉性能试验规程锅炉性能试验规程 History and Overall Introduction Brian Vitalis Senior Technical Advisor PTC 4 Launch Event in Xian China 4-6 June 2019 2019 Babcock Power Inc.  All Rights Reserved 2 Scope of Presentation History and Introduction of ASME PTC 4 1. Brief History 2. PTC 4.1 1964 Key concepts 3. Reasons for changes 4. PTC 4 1998, 2008, 2013 5. Key concepts scope / outline 2019 Babcock Power Inc.  All Rights Reserved 3 History First ASME boiler efficiency code in 1884 1884 First ASME boiler efficiency code 1915 Issued as set of 10 PTC codes revisions 1946 PTC 4.1 Modernize, better address the increasing size of units 1964 PTC 4.1 Complete re-write.  Increasing unit size.  Includes Short Form revision activity 1998 PTC 4 Complete re-write.  Introduce uncertainty. 2019 PTC 4 translation / launch in China revn 2019 Babcock Power Inc.  All Rights Reserved 4 PTC 4 Series of Codes: Parts of the Boiler PTC 4: Overall boiler / steam generator PTC 4.2: Pulverizers PTC 4.3: Air heaters PTC 4.4: Heat recovery type steam generators PTC 11: Fans PTC 21: Particulate collection PTC 40: FGD 2019 Babcock Power Inc.  All Rights Reserved 5 Other PTC Test Codes in Power Plant And many others PTC 4:  Boiler /  Steam Generator PTC 6: Steam Turbine PTC 12.2:  Condenser PTC 12.3:  Deaerators PTC 12.1:  Feedwater Heaters PTC 46: Overall power plant 2019 Babcock Power Inc.  All Rights Reserved 6 PTC 4.1 1964 Basic Concepts Gross Efficiency Definition Output (heat added to steam) Credits Losses Input Gross Input (energy from fuel plus any heat credits) 2019 Babcock Power Inc.  All Rights Reserved 7 PTC 4.1 1964 Basic Concepts Efficiency: Input-Output and Heat Loss Methods Output (heat added to steam) Credits Losses Input Gross Input (energy from fuel plus any heat credits) For Heat Loss method, Measure only the losses and credits Reduced need to measure flow rates, since air and flue gas quantities may be expressed relative to the fuel heat quantity. For Input-Output method, Need to measure flow quantities of both input and output. Measurement uncertainties on these large quantities can have large effect on uncertainty of result. 2019 Babcock Power Inc.  All Rights Reserved 8 PTC 4.1 1964 Short Form Short Form Obsolete / No longer used Use of Code prior to widespread use of computers called for some simplification. The 1964 revision in use until the 1998 replacement included Short Forms which were manual calculation tables. Among other simplifications, they omitted calculation of the heat input credits. There are now no longer similar shortcuts prescribed in the current Code, but the Code does allow Parties to the test to agree to simplifications to suit their needs. 2019 Babcock Power Inc.  All Rights Reserved 9 PTC 4.1 1964: Revision / Re-write Why revise it? PTC 4.1-1964 continued to be used and was periodically re-affirmed throughout the period of accelerated power plant building and scale-up in USA:  1960s through 1980s. It was one of the most used ASME codes ever published. So, why did we want to change it? A continuing need to keep up with new, larger boiler technology including supercritical pressures and the greater commercial values placed on boiler efficiency; To address the special considerations for fluidized bed boilers; To account for new measurement technology; To take advantage of increasing availability of computers for calculations. This was especially helpful in calculating enthalpy (heat content) of various fluids, instead of the prior graphical method of approximating specific heat of fluids; To implement concept of Fuel Efficiency, for alignment with overall plant evaluation considerations; Add procedures for calculating uncertainty of the results, in order to plan the level of test effort according to the needs of the situation (large or small unit, large or small commercial values at stake, acceptance test or routine monitoring test, and so on.). 2019 Babcock Power Inc.  All Rights Reserved 10 PTC 4 1998 was another complete re-write The code number identifier and title were revised To better signify its overarching scope, the boiler efficiency test code was elevated in number, as PTC 4 (replacing 4.1, which was made obsolete). The other 4-series test codes for subsystems and equipment (e.g. PTC 4.3 for air heaters) are still used, but this equipment is included within the system envelope of PTC 4. The code was re-named Fired Steam Generators. Although it uses much of the same methodology from PTC 4.1, there are a few notable changes in concept. In addition to the few changes in concept, the update explains and defines the calculations in much greater detail than before, while allowing for each test to be customized or simplified to suit the purpose of each project. 2019 Babcock Power Inc.  All Rights Reserved 11 PTC 4 1998: Change definition or basis of efficiency measure Applied a different definition of efficiency The earlier PTC 4.1 used what some may consider an intuitive technical concept of efficiency, where the energy input to the system includes ALL energy and heat sources relative to the Reference Temperature.  We call this Gross Efficiency. .Gross meaning complete or total, in referring to the energy Input to the system. However, the Short Form provided in that Code omitted the determination of sensible heat inputs (called Credits), and in the days before widespread computer use, such shortcuts were typically followed. So, rather than considering the total or Gross energy input to the system, many users were considering only the chemical energy from the fuel (the fuels heating value) as input to the system. Evaluations of the complete power plant performance also favored expressing performance relative to only the fuels heating value, since that is how fuel is typically priced, and plant economics are determined. In spite of not including sensible heat credits in the Input, there is a way to account for these additional energy streams as efficiency Credits, which are now to be determined separately from the efficiency Losses. The committee considered 16 different but all technically correct efficiency definitions. x 2019 Babcock Power Inc.  All Rights Reserved 12 Fuel Efficiency Gross Efficiency PTC 4 1998: Change definition or basis of efficiency measure Applied a different definition of efficiency x energy added to steam Fuel HHV plus all other energy inputs or Credits Fuel HHV only Here, the effect of all input Credits are spread and diluted among all efficiency losses In this method, input Credits are each determined separately from Losses Input: How the energy input Credits are accounted for: 2019 Babcock Power Inc.  All Rights Reserved 13 Gross vs. Fuel Efficiency: Conceptual Comparisons Gross Efficiency (PTC 4.1) Fuel Efficiency (PTC 4) EfficGross = 100% - %Losses EfficFuel = 100% - %Losses + %Credits Each of the losses is expressed as percentage of Gross heat input, or Each of the losses is expressed as percentage of the Fuel HHV heat input, or Note that the effect of input Credits is distributed and affects the value of all calculated Losses. Note that the input Credits do not affect the value of the Losses. There is no discrete accounting of each of the input Credits (but their combined effect is distributed among the Losses). The heat input Credits in this case are individually calculated and reported, in a manner similar to the Losses. %Loss = ( + ) %Loss = ( ) With a net positive value of input Credits, For each Gross Efficiency Loss value, the corresponding value on Fuel Efficiency basis will be greater. For Gross Efficiency, Input credits are not individually accounted for. For Fuel Efficiency, they offset the Losses. Compared to overall Gross Efficiency value, the Fuel Efficiency value will be greater. However, both bases account for all of the same energies into and out of the system, and will result in the exact same calculated fuel flow rate. EfficGross = ( +) EfficFuel= ( ) MrF = 100 - 2019 Babcock Power Inc.  All Rights Reserved 14 ASME PTC 4.1-1964 Reaffirmed 1991 2019 Babcock Power Inc.  All Rights Reserved 15 PTC 4 Code Structure / Organization Sect. Title Contents / Practical Application 1 Object and Scope Provides several variations of steam generator process / boundary diagrams Identify equipment to include within energy balance, and the fluid streams which must be measured (IN / OUT) 2 Definitions / Terms For reference. Includes definitions, abbreviations, units and conversions Note: Code is now in process of being converted from US units to SI units as primary un