Abstracts and Key Words

HeatSourceandColdSourceTechnologyApproachesofWasteHeatUtilizationforThermalPowerPlantFlueGasandCirculatingCoolingWater
ZHANG Ruoyu，WANG Haichao， LI Xiangli，DUANMU Lin

Abstract： The application of waste heat recovery of boiler flue gas in thermal power plant in the eliminating process of white flue gas and the utilization approaches of waste heat of condenser circulating cooling water are reviewed. The eliminating process of white flue gas to use the flue gas waste heat includes flue gas reheating method，flue gas condensation method，flue gas condensation and reheating method. The flue gas condensation and reheating method realizes reasonable utilization of flue gas waste heat through multiple sets of different heat exchangers. The utilization approaches of circulating cooling water waste heat divide into absorption heat pump utilization and electrically driven heat pump utilization. In order to achieve heating，the absorption heat pump is operated in conjunction with the heater of heat-supply network，or multiple absorption heat pumps are used for cascade heating of the return water in heat-supply network. The electrically driven heat pump has a high energy efficiency ratio and can absorb wind power.

Keywords: thermal power plant; flue gas waste heat; waste heat of circulating cooling water; eliminating white flue gas

PredictionofWaterSupplyTemperatureinHeatingSystemBasedonArtificialNeuralNetwork
HU Jiangtao，WANG Xinke，LIU Gang

Abstract： A heating test system is established. The test data are water supply temperature，indoor temperature，outdoor temperature and solar irradiance. The data acquisition time interval is set to 0.5 h. BP neural network and Elman neural network are selected，and the indoor temperature，outdoor temperature and solar irradiance are used as input data to predict the water supply temperature. 500 groups of test data are selected to optimize the training of the neural network，and determine the number of input data groups and other parameters. 50 groups of test data are selected to verify the accuracy of the two neural networks for predicting water supply temperature. The prediction abilities of BP neural network and Elman neural network were evaluated on February 4 and 5，2018 (the indoor temperature was set to 16 ℃). The number of input data groups of the two neural networks is 7 groups (that is，in order to predict the water supply temperature，in addition to the current test data set，the data groups of the first 6 moments should also be inputted). The water supply temperature predicted by BP neural network and Elman neural network is basically consistent with the actual water supply temperature. The maximum relative errors are -5.66% and 4.32%，respectively. The water supply temperature predicted by BP neural network and Elman neural network can maintain the indoor temperature. Compared with the set indoor temperature，the fluctuation ranges are ±1 ℃and -0.8 to 0.9 ℃，respectively. The prediction ability of Elman neural network is stronger.

Keywords: BP neural network; Elman neural network; prediction of water supply temperature; indoor temperature

Heat-supplyNetwork，Cooling-supplyNetworkandSubstation

KeyPointsofSteamPipelineDesigninUtilityTunnel
ZHOU Chunli

Abstract： The key points of the steam pipeline design in utility tunnel (steam trap device，compensation mode and adiabatic design) are analyzed. A short pipe for collecting condensed water is set at connection between steam trap pipe and steam pipeline，and the steam trap pipe is connected to the side of the short pipe. The steam trap valve group is arranged under the steam pipeline for easy operation，and the outlet steam trap pipe of steam trap valve group is led upward from the side wall of the utility tunnel and directly buried to the nearby steam trap well. For straight pipe sections with working pipe specification of less than DN 250 mm，an external pressure axial type bellow expansion joint can be used. For straight pipe sections with working pipe specification greater than or equal to DN 250 mm，an axial pressure balanced bellow expansion joint can be used. For the inverted siphon，a natural compensation or a large tie rod type bellow expansion joint can be used. The traditional insulation material closest to the working pipe is replaced with nano aerogel felt to reduce the outer diameter of the steam pipeline. The design of the steam pipeline insulation support is based on the reduction of the metal connection area to effectively control heat loss.

Keywords: utility tunnel; steam pipeline; steam trap device; compensation mode; adiabatic design

DeformationAnalysisofSuper-largeSteelTrussforHeatingPipeline
LIU Shiyu

Abstract： The steel truss for heating pipeline produces expansion and contraction deformation due to the seasonal temperature difference, and the thrust of the pipeline acts on the fixed anchor, which causes the tensile and compression deformation of the truss. Taking the super-large steel truss of a heating pipeline project as an example, two methods are used to analyze the deformation of the steel truss. The mechanical formula method is based on the fixed anchor thrust data, and the mechanical formula is used to calculate the deformation. The Midas software method uses the Midas software to establish the overall model of the heating pipeline and the steel truss and calculate the deformation. The calculation results show that the thrust of the heating pipeline has little effect on the deformation of the truss, and the deformation of the truss is composed mainly of the thermal expansion and contraction deformation caused by the seasonal temperature difference. The two methods of the mechanical formula and the Midas software have the same deformation direction. The Darth software method has a smaller deformation amount.

Keywords: heating pipeline; super-large steel truss; deformation; fixed anchor thrust; Midas software

BuildingHeating，AirConditioning，VentilationandThermalEnvironmentInfluenceofOccupantWindowingBehaviouronComprehensiveHeatTransferCoefficientofBuildingEnvelope
PENG Peng, TIAN Zhe, LU Yakai

Abstract： Based on the heat balance analysis method, the basic heat transfer coefficient of the building envelope reflecting the insulation performance and air tightness of the building envelope as well as the comprehensive heat transfer coefficient comprehensively considering the insulation performance and air tightness of the building envelope and the windowing ventilation heat release caused by the occupant windowing behaviour are defined. Taking a residential building in Tianjin as an example, the actual measurement and questionnaire are used to analyze the influence of occupant windowing behaviour on the comprehensive heat transfer coefficient of the building envelope. As the indoor and outdoor temperature difference decreases (the corresponding outdoor temperature rises on the premise that the indoor temperature remains basically stable), the increase in the comprehensive heat transfer coefficient of the building envelope is caused by an increase in the occupant windowing behaviour. As the indoor and outdoor temperature difference increases, the decrease in the comprehensive heat transfer coefficient of the building envelope is caused by a decrease in the occupant windowing behaviour, so that the comprehensive heat transfer coefficient of the building envelope tends to the basic heat transfer coefficient of the building envelope. The results are basically consistent with the results of the resident questionnaire (when the outdoor temperature is higher, the occupant windowing phenomenon is more common; when the outdoor temperature is lower, the windowing time is reduced, or even the window is not opened). Taking the comprehensive heat transfer coefficient of the building envelope under different indoor and outdoor temperature differences as the data sample, the indoor and outdoor temperature difference at the inflection point of the occupant windowing behaviour is calculated by the Pearson correlation analysis method. For the residential building, the indoor and outdoor temperature difference at the inflection point of the occupant windowing behaviour is 24.02 ℃.

Keywords: residential building; building envelope; windowing behaviour; comprehensive heat transfer coefficient

RenewableEnergy，DistributedEnergySourceandCombinedCooling，HeatingandPowerEconomicComparisonofGasTurbineInletAirCoolingMode
GUO Jiasheng，LIU Yuquan，BAO Chun， LI Yong，LIU Wei

Abstract： Taking a gas distributed energy station in a certain park in Guangzhou (using gas turbine as the prime mover) as an example，it is proposed that the steam-type lithium bromide absorption chiller (hereinafter referred to as absorption chiller) and the electric refrigeration unit are used to cool the gas turbine inlet air. The selection and cost estimation of two types of refrigeration equipment are performed. Under the condition of 100% annual load rate (the load rate of power generation) of the gas turbine generator set，the gas consumption of the gas turbine before and after the gas turbine inlet air cooling，the output electric power of the gas turbine generator set and the steam production of the waste heat boiler are estimated. The project revenue and static investment payback period when using two types of refrigeration equipment are calculated to determine the optimal refrigeration equipment. The costs of the absorption chiller and the electric refrigeration unit are 420×104and 350×104yuan，respectively. The typical annual project incomes are 45.43×104and 213.45×104yuan，respectively. The static investment payback periods are 9.24 and 1.64 years，respectively. The electric refrigeration unit is used to cool the gas turbine inlet air，which is economical.

Keywords: gas turbine; inlet air cooling; income; static investment payback period

GasCombustion，GasAppliancesandGasConsumptionEquipmentDevelopmentofMulti-gasSourceMixedCombustionDevice
HOU Liquan，SHI Lei，ZHANG Changjian， HOU Beiran，XIONG Chuchao， LIU Huan，LUO Jinghui

Abstract： Coke oven gas，mine gas and natural gas are difficult to achieve good combustion results on one boiler due to their different pressures and low calorific values. In view of this，a multi-gas source mixed combustion device (has been authorized by the national invention patent) is developed. The multi-gas source mixed combustion device is mainly composed of combustible gas mixing device，diffusion burner，blower，combustible gas and air ratio control device，ignition gun，fire detection device，valve group，main control cabinet and so on. A buffer tank has been added to the conventional structural design，equipped with a special frequency converter fan and an electric ball valve，which are automatically controlled by a program in the process of the purging，ignition，gas-air ratio，combustion，load regulation and flameout. Coke oven gas，mine gas and natural gas can be burned separately or two or three gas sources can be burned simultaneously.

Keywords: multi-gas source; mixed combustion device; swirling diffusion burner; mobile servo device; ignition device

EvaluationofOperationPerformanceofGas-firedHeatingandHotWaterCombi-boilersBasedonPrincipalComponentAnalysis
ZHOU Weiye，LIU Wenbo， LYU Xinyu，WANG Yan

Abstract： Six indicators including the heating heat efficiency at the rated heat input during the operation of the gas-fired heating and hot water combi-boilers，the O2volume fraction in the dry flue gas，the CO volume fraction in the dry flue gas，the CO2volume fraction in the dry flue gas，the NOxvolume fraction in the dry flue gas and the flue gas exhaust temperature are selected，and 40 samples are randomly selected for related experiments. The operation performance evaluation model of gas-fired heating and hot water combi-boilers is established by principal component analysis. The principal component analysis results show that the three principal component indexes converted by this method can replace 88.9% information of the original six indicators. This method can simplify complex information and obtain quantitative evaluation indicators，which can be applied to quantitative evaluation of the operation performance of gas-fired heating and hot water combi-boilers. Considering the non-uniqueness of the feature vector，it should be paid attention whether the feature vector selected by the software is suitable，and the verification and determination methods are given. The verification results show that the feature vector selected by SPSS data analysis software is suitable for the principal component 1 and principal component 2 in the paper case，is not suitable for the principal component 3，and should be multiplied by -1 before participating in the operation.

Keywords: gas-fired heating and hot water combi-boiler; operation performance evaluation model; principal component analysis; feature vector

GasTransmission，Distribution，StorageandTransportation

GasPipelineDeformationunderGroundSubsidenceCausedbyPipeJackingConstruction
XIE Tongcai，WU Hua，HUANG Nan

Abstract： Based on the theory of ground subsidence trough，the ground subsidence caused by the pipe jacking construction of a water supply pipeline is analyzed，and the maximum ground subsidence，the width of the subsidence trough and the bending curvature radius of gas pipeline caused by ground subsidence are calculated. According to the relevant specifications，the minimum allowable curvature radius of gas pipeline is obtained，and whether the curvature radius of the gas pipeline meets the requirements is determined. The video of the world largest pipe jacking construction project is included at the end of the paper.

Keywords: third party construction; gas pipeline deformation; ground subsidence; subsidence; subsidence trough; curvature radius

ExperimentalStudyonPressureRegistrationCharacteristicsofInternalRegistrationGasRegulator
ZHAI Jun，LI Haomin，HU Jing， YUE Ming，CHEN Hao

Abstract： The test system of internal registration regulator is set up. A DN 40 mm medium-low pressure internal registration regulator is selected as the measured regulator. Taking air as the experimental medium，the variations of the outlet pressure of the regulator and the signal tube collecting pressure with the flow rate are tested at the inlet pressures of 0.10，0.25 and 0.40 MPa，respectively. Under the condition of the inlet pressure of 0.10 MPa，the outlet pressure of the regulator decreases with increase of the flow rate. At the inlet pressures of 0.25 MPa and 0.40 MPa，the outlet pressure of the regulator increases first and then decreases with increase of the flow rate. At each inlet pressure，the signal tube collecting pressure decreases with increase of the flow rate. The pressure registration deviation of the internal registration regulator (the difference between the outlet pressure of the regulator and the signal tube collecting pressure) is proportional to the second power of the flow rate. The proportional coefficient gradually increases with increase of the inlet pressure of the regulator.

Keywords: internal registration regulator; pressure registration characteristics; outlet pressure; signal tube collecting pressure; pressure registration deviation

NaturalGasSupplySystemofBenchTestforMarineDualFuelEngine
SU Dongwang， XU Xiuqin

Abstract： Combining with engineering example，the design of natural gas supply system of bench test for marine dual fuel engine is discussed. Taking the municipal medium-pressure pipeline natural gas or LNG as the gas source，the process flow and type selection of main equipment are discussed. The design of the gas supply of the double wall pipe，the annular space ventilation and the inner pipe purging in the gas supply system is carried out.

Keywords: marine; dual fuel engine; bench test; gas supply system; double wall pipe; jacketed pipe

LiquefiedNaturalGas

CalculationofEvaporationRateof150m3LNGStorageTankandExperimentalAnalysisofInfluencingFactors
ZHOU ke，ZHU Bo

Abstract： The calculation method of the evaporation rate of LNG storage tank is given. Taking a 150 m3LNG storage tank as an example，the composition of natural gas is obtained by sampling and detecting the evaporated natural gas，and the density of each component under the standard conditions is queried. The evaporation rate of the LNG storage tank is calculated by the measured gas-phase space pressure，temperature and liquid level. The effects of initial filling rate，nitrogen content of LNG and ambient temperature on the evaporation rate of the storage tank are analyzed. The study finds that the daily evaporation rate of the storage tank increases with time，but the increase magnitude decreases. The lower the initial filling rate，the higher the evaporation rate of the storage tank，and too low filling rate of the storage tank should be avoided as much as possible. The higher the nitrogen content of LNG，the lower the evaporation rate of the storage tank. Filling nitrogen into the storage tank can effectively inhibit the evaporation of LNG. The higher the ambient temperature，the greater the evaporation rate of the storage tank，the faster the pressure rise in the LNG storage tank，and the shorter the safe storage time of LNG.

Keywords: LNG storage tank; evaporation rate; initial filling rate; nitrogen content; ambient temperature

BuildingGasSupply

DesignSchemeofGasEmergencyAutomaticShut-offValveinCommercialComplex
LI Boqi，CHEN Lu

Abstract： Three design schemes of gas emergency automatic shut-off valves in commercial complex are discussed，including regulator box total control type，floor-isolated control type and merchant-isolated control type. In front of the main control valve at the regulator box outlet，in front of the floor branch control valve and in front of the merchant control valve，the emergency automatic shut-off valve step is set up step by step，and the control range of each emergency automatic shut-off valve is subdivided step by step. The system layout，advantages and disadvantages of the three schemes are analyzed，and suggestions are given.

Keywords: commercial complex; emergency automatic shut-off valve; gas alarm control system

GasEquipmentandMaterials

AnalysisofFatigueLifeofDiaphragmforCityGasPressureRegulator
YAN Rongsong，ZHAO Zijun，GAO Wenxue， YANG Wenliang，ZHAI Jun

Abstract： Based on the mechanical properties of city gas pressure regulator diaphragm samples (hereinafter referred to as diaphragm)，the instantaneous tensile stress-strain relationship of the sample is measured，and the Mooney-Rivlin model is determined as a sample constitutive model. The maximum tensile stress fatigue life curve of the sample is obtained by experiment. With the help of ANSYS software，a three-dimensional model of the diaphragm is established，and the equivalent stress cloud of the diaphragm is simulated using the Mooney-Rivlin mode. The average stress and maximum tensile stress under the equal life condition for the maximum tensile stress fatigue life curve are corrected using the Goodman model. The vulnerable position and the fatigue life of the diaphragm under the conditions of 3 kPa and 10 kPa are predicted by simulating the opening and closing process of the gas pressure regulator through 103 333 cycles. The results show that the equivalent stress of the diaphragm caused by the pressure load is the largest at the corrugated section，and the diaphragm corrugation section is the main vulnerable part of the diaphragm. Before and after the cycle，the maximum equivalent stress at a pressure load of 10 kPa is 1.4 times the maximum equivalent stress at a pressure load of 3 kPa. At pressure loads of 3 kPa and 10 kPa，the maximum equivalent stress experienced by the diaphragm after the cycle is 2.5 times the maximum equivalent stress before the cycle. The fatigue life of the diaphragm is 57 066 times at a load of 3 kPa，and the fatigue life of the diaphragm is 33 004 times at a load of 10 kPa. From a security perspective，taking the most unfavorable working conditions，the fatigue life of the diaphragm in actual engineering applications is determined to be 33 004 times，which is 1.1 times the design life (30 000 times).

Keywords: city gas pressure regulators; diaphragm; constitutive model; tensile stress fatigue life curve

AdaptabilityofRemoteICCardGasMeterinFieldofDomesticGasMetering
SHAO Zehua

Abstract： Combined with the current situation of remote IC card gas meter in China，the function and operating system of remote IC card gas meter adopting short-range wireless communication technology and remote wireless communication technology are introduced. The analysis believes that the remote IC card gas meter adopting short-range wireless communication technology has low measurement accuracy，high labor intensity for meter-reading，low efficiency and poor information security，and that the remote IC card gas meter adopting remote wireless communication technology has redundant function，complicated operating system，low communication performance，low information security，high power consumption and no guaranteed gas safety. It is pointed out that the remote IC card gas meter cannot meet the needs of gas companies and gas users for safety，fairness and wisdom，and is not applicable in the field of domestic gas metering. The corresponding solution is given：upgrade the ordinary IC card gas meter as an overall design and IC card smart gas meter with information security function or upgrade to a remote control smart gas meter supporting low-power WAN communication technology，and after the popularization of the IOT smart gas meter，natural gradual replacement can be realized. The IOT smart gas meter is a product that represents the development direction of gas meter.

Keywords: remote IC card gas meter; short-range wireless communication; remote wireless communication; IOT smart gas meter

GasInformatization

CompositionandApplicationofIntegratedPlatformforSmartGasSafeOperation
GUO Weidong，LIU Bin，QIN Yong

Abstract： The production and operation services of gas enterprises are divided into three stages：engineering construction period，operation service period and value-added service period. The composition of the integrated platform for smart gas safe operation and its application in three stages are discussed.

Keywords: geographic information system; smart gas; safe operation; gas value-added service; platform

DesignandApplicationPracticeofSmartGasEngineeringProjectManagementPlatform
FANG Rui，CONG Peixue，QIU jun

Abstract： Combining with the actual situation of the engineering construction，the smart gas engineering project management platform is established，including four subsystems：engineering project management system，engineering construction management system，engineering inspection management system and engineering statistical analysis system. The functions of the four subsystems are introduced，the technical implementation of the engineering project management platform is analyzed，and the application effects are introduced.

Keywords: smart gas; engineering project management platform; engineering management; engineering construction; engineering inspection

GasStandardsandCodes

SuggestionsonRevisingGasStorageandPeakShavingProvisionsinCodeforDesignofCityGasEngineering
YAN Haipeng，MA Junfeng，HAN Xu

Abstract： The current situation of the serious insufficiency of natural gas storage and peak shaving capacity in China as well as the policy requirements for deepening the reform of natural gas system and building a multi-level natural gas reserve system are analyzed. The reasons and basis of revising the relevant provisions of gas storage and peak shaving in theCodeforDesignofCityGasEngineeringare expounded. By thinking from the aspects of the concept and mutual relationship of peak shaving and gas storage，main body of peak shaving responsibility，quantification of gas storage responsibility，calculation base of gas storage scale，gas storage mode and transportation guarantee and principle of alternative gas source for reserve，the concrete problems existing in the revision of the code and the suggestions are proposed.

Keywords:codefordesignofcitygasengineering; reform of petroleum and natural gas industry; production，supply，storage and marketing system; gas storage and peak shaving; natural gas reserve; underground gas storage reservoir; LNG receiving station; interconnection

RevisionofTechnicalSpecificationforPolyethyleneFuelGasPipelineEngineering
LIN Wenzhuo，BAI Liping，GAO Lixin，ZHAO Qihui

Abstract： Compared withTechnicalSpecificationforPolyethylene(PE)FuelGasPipelineEngineering(CJJ 63-2008)，the major revised standard clauses inTechnicalStandardforPolyethylene(PE)GaseousFuelPipelineEngineering(CJJ 63-2018) are discussed，including maximum working pressure and maximum allowable working pressure，allowable storage time and storage conditions，welded fitting problems，hot-fusion equipment and connection requirements，hot-fusion joint quality inspection，tracing，warning device and protection board settings. The basis and origin of the revision of these clauses are introduced.

Keywords:technicalstandardforpolyethylene(PE)gaseousfuelpipelineengineering; standard revision; standard paraphrase (interpretation)

GasEnterpriseManagement

DisposalofNaturalGasWeldingTorchBlockageCausedbyPipeWaterAccumulation
GENG Tongmin，HOU Fenglin，DU Keli，LIU Xiaoling

Abstract： In order to solve the blockage of gas welding torch in general assembly workshop of an air conditioning company，the water dew point at different locations of the natural gas pipeline network is tested，while the water content of natural gas is analyzed. It is concluded that there is water accumulation at the end of the buried pipeline network before the gas service pipe of the general assembly workshop. The processes such as pressure maintenance，gas release，replacement and purge of the courtyard pipeline network are carried out to discharge the water accumulated in the courtyard pipeline network. The blockage caused by the excessive water content of natural gas in the natural gas welding torch is solved.

Keywords: welding torch blockage; courtyard pipe water accumulation; water dew point; water content

ManagementandApplicationofDomesticIntelligentGasMeterunderDifferentMeterReadingModes
QIAO Heng，SHEN Xiaodong，SHEN Yue

Abstract： The importance of metering management of gas meters is indicated，and the current status of metering management of diaphragm gas meters for residential users is described. The classification，application comparison and development suggestions of intelligent gas meters for residential users are given. The annual costs of pure manual meter reading mode，intelligent remote meter reading mode and mobile APP self-service meter reading combined with manual meter reading mode are analyzed.

Keywords: metering management of intelligent gas meter; unaccounted-for-gas rate; meter reading mode; mobile APP self-service meter reading