石油化工企业可燃气体和有毒气体检测报警设计规范.doc

中国最大的资料库下载中国最大的资料库下载 UDCUDC SH Trade Standards of the People s Republic of China 中华人民共和国行业标准中华人民共和国行业标准 P P SHSH 3063 3063 19991999 Specifications for Design of Combustible Gas and Toxic Gas Detection and Alarm Systems in Petrochemical Industry 石油化工企业可燃气体和石油化工企业可燃气体和 有毒气体检测报警设计规范有毒气体检测报警设计规范 Issued on 15 Apr 1999 Executed since 1 Sept 1999 1999 04 15 发布发布 1999 09 01 实施实施 ISSUED BY THE STATE PETROLEUM AND CHEMICAL INDUSTRY BUREAU 国家石油和化学工业局国家石油和化学工业局 发布发布 The Chinese version of standards has precedence to their English translations which are only for internal reference 本英文版为内部资料 仅供参考 以中文 版为准 1 PREFACE The Specifications are revised by this corporation based on the original specifications Specifications for Design of Combustible Gas Detection and Alarm Systems in Petrochemical Industry SH3063 94 according to the notification of the file 1996 JBZ No 250 issued by SINOPEC The specifications consist of six chapters and two appendices The major purpose of this revision is to add the contents on the design of toxic gas detection and alarm In the revision course the problem that the original specifications contains no content on the design of toxic gas detection and alarm has been given broadly invested and studied practical experiences in toxic gas detection and alarm in petrochemical enterprises in the last years have been summarized suggestions and opinions from relevant design production research and development and detecting instrument aspects have been collected and some key issues are discussed many times finally this final version of the Specifications is confirmed If any part in the Specifications is found to revise or supplement in its implement please offer your suggestion or data to this corporation for reference in future further revision The contact address of this corporation No 27 Zhongzhou W Rd Luoyang Henan 471003 The Specifications is compiled mainly by Luoyang Petrochemical Engineering Corporation SINOPEC Units participated the complement of the Specifications include Lanzhou Design Institute SINOPEC The Instrument Plane of Yanshan Petrochemical Corporation SINOPEC Shenzhen Anhui Industrial Co Main drafters of the Specifications are Wang Huaiyi Wang Yubin Wang Zipin 2 CONTENTS 1 GENERAL PRINCIPLES 3 2 TERMINOLOGY AND SYMBOLS 3 2 1 Terminology 3 2 2 Symbols 3 3 COMMON STIPULATIONS 4 4 DETERMINATION OF DETECTION POINTS 5 4 1 Processing installations 5 4 2 Storage transportation Facilities 6 4 3 Locations where Combustible Gases and Toxic gases Diffuse and Accumulate 7 5 DETECTION ALARM SYSTEMS OF COMBUSTIBLE GASES AND TOXIC GASES 8 5 1 System composition and performance 8 5 2 Selection of the detectors 9 5 3 Selection of Alarms or Indicator alarms 10 6 INSTALLATION OF ALARMS FOR COMBUSTIBLE GASES AND TOXIC GASES 12 6 1 Installation of the detector 12 6 2 Installation of alarms or indicator alarms 12 APPENDIX A PROPERTIES TABLE OF COMBUSTIBLE GASES TOXIC GASES AND THEIR VAPORS 13 ATTACHMENT ELUCIDATION OF SOME TERMS USED IN THE SPECIFICATIONS 19 3 1 GENERAL PRINCIPLES 1 0 1 The Specifications are formulated in order to ensure the safety production and or personal safety in petrochemical enterprises by detecting the concentration of possibly leaked combustible gases and toxic gases and timely making alarm to prevent fire and or explosion hazard 1 0 2 The Specifications are applicable for the design of the detection and the alarm of combustible gases and toxic gases for petrochemical enterprises 1 0 3 The current relevant mandatory standards and specifications should be met in addition to the Specifications 2 TERMINOLOGY AND SYMBOLS 2 1Terminology 2 1 1 Combustible gas The combustible gas for the purpose of the Specifications means the gases in Class A which lower explosive limits are below 10 v v or the difference between both the upper and lower limits are more than 20 v v or the combustible gases or those containing small amount of toxic gases which are formed from liquefied hydrocarbons combustible liquids in Classes Ab and Ba by vaporization 2 1 2 Toxic gas The toxic gas for the purpose of the Specifications means hydrogen sulfide hydrogen cyanide chlorine carbon monoxide acrylonitrile epoxyethane and chlorethylene 2 1 3 Allowable maximum concentration It means the allowable maximum concentration of a or some hazardous substance s in the workshop air i e the figure which is not allowed to exceed for the hazardous substance s in the sir in working place where workers undertake their job The figure is also called as the highest limit 2 2 Symbols 2 2 1 LEL means the lower explosive limit v v of a combustible gas 2 2 2 TLV means the allowable maximum concentration of a hazardous substance in the workshop air 4 3 COMMON STIPULATIONS 3 0 1 In a Region 2 or additional Region 2 where combustible gases will be used or produced in the processing installations or storage transportation facilities including the tank farms handling facilities and filling stations used for gases in Class A liquefied hydrocarbons liquids of Class Ab combustible gas detection and alarm instruments should be set in conformity with the Specifications In the Region where toxic gases will be used or produced in the processing installations or storage transportation facilities toxic gas detection and alarm instruments should be set in conformity with the Specifications 1 For a combustible gas or the gas containing a toxic gas and it may be caused from a leakage event that the concentration of the combustible gas reaches 25 of LFL and the toxic gas cannot reach the allowable maximum concentration a combustible gas detecting alarm instrument should be set 2 For a toxic gas or the gas containing a combustible gas and it may be caused from a leakage event that the toxic gas reaches the allowable maximum concentration and the concentration of the combustible gas cannot reach 25 of LFL a toxic gas detecting alarm instrument should be set 3 For a gas which is both combustible and toxic only one toxic gas detecting alarm instrument needs to be set 4 For a place where are a or some combustible gas es and a or some toxic gas es a combustible gas detection and alarm instrument and a toxic gas detecting and alarm instruction should be simultaneously set Note For the division of Region 2 or Additional Region 2 see the Specifications for Design of Power Installations in the Environments with Explosive and Fire Hazard GB 50058 3 0 2 The monitor alarm of combustible gases and toxic gases should be the alarms of Class I or Class I1 The routine monitor alarm should be Class I alarm For the process that needs an interlocking protection system Class I or Class II alarm should be adopted A junction output signal is transmitted to the interlocking protection system at the same of Class II alarming 3 0 3 For the hazardous area where nobody is allowed to enter as required for the sake of a special processing need necessary recording or printing device should be done in addition to implementation of the continuous detection indication alarm of the releasing source of the combustible gas and or the toxic gas 3 0 4 The alarm signal should be transmitted to the control room or operation posts where are operators constantly watched the processing installations and storage transportation facility 3 0 5 All combustible gas detection and alarm instruments must be subject to certification of a state designated institution and a state authorized inspection unit in manufacture explosion proof and fire proof performances of their measuring instruments All toxic gas detection and alarm 5 instruments must be subject to certification of a state designated institution and a state authorized inspection unit in manufacture of their measuring instruments All toxic gas detection and alarm instruments of flame proof type must be subject to certification of a state designated institution and a state authorized inspection unit in explosion proof performances of their measuring instruments in addition to that for the common type 3 0 6 Any enterprise that uses the combustible gases and toxic gas alarm instruments should be equipped with the necessary standardization device and standard gas 3 0 7 The detector should be set on the windward side of the least frequent wind direction at the releasing source of the combustible gas or toxic gas 3 0 8 The radius of the effectively detectable horizontal plane of a combustible gas detector should be 7 5 m for indoor use or 15 m for outdoor use Usually one detector may be set for the effective coverage The distance of a toxic gas detector from the leasing source is preferably not more than 2m for outdoor use or 1m for indoor use 3 0 9 According to the stipulation in for the Specifications the combustible gas alarm or toxic gas alarm of fixed type should be adopted for the place where the alarm should be set In case it is impracticable to set the alarm of fixed type for insufficient condition the portable detection and alarm instrument should be equipped 4 LOCATION OF THE DETECTION POINTS 4 1 Processing installations 4 1 1 Detectors should be set at the following releasing sources of combustible gases or toxic gases 1 The compressors for gases of Class A or toxic gases the pumps for liquefied hydrocarbons and the dynamic seals of pumps for liquids Class Ab liquids or of the multicell pumps for liquids Class Ba and of the pumps for the liquids which may volatilize out toxic gases 2 The sampling port from which the gases of Class A liquefied hydrocarbons or liquids of Class Ab or the liquids which may volatilize out toxic gases may leak in the case of abnormal running and the liquid discharge outlets which may discharge liquids containing liquefied hydrocarbons liquids of Class Ab or the liquids which may volatilize out toxic gases in the case of abnormal running 3 The flange and valve group on equipment or pipelines from which gases of Class A toxic gases or liquefied hydrocarbons may leak in the case of abnormal running 4 1 2 For those releasing sources stipulated in Clause 4 1 1 and located in a completely or partially open area of equipment if the detection point set on the windward side of the least 6 frequent wind direction The distance of the detection point from the releasing source should not be more than 15 m for the combustible gas detection or 2m for the toxic gas detection if the detection point set on the leeward side of the least frequent wind direction the distance should not be more than 5 m for the combustible gas detection or 1m for the toxic gas detection 4 1 3 For those releasing sources stipulated in Clause 4 1 1 and located in a completely or partially enclosed factory building a detector per 15 m should be set and the distance of the combustible gas detector from any releasing source is not be more than 7 5 m preferably The distance the toxic gas detector from any releasing source is not more than 1 m preferably 4 1 4 When equipments of different classes of fire hazard are located in a completely or partially enclosed factory building the detector should be set within the scope of 7 5 m from the releasing source stipulated in Clause 4 1 1 4 1 5 For the leasing source of a combustible gas that is lighter than air stipulated in Clause 4 1 1 located in a completely or partially enclosed factory building a or more detector s should be set at the highest point easy to accumulate the combustible gas in addition to a detector to be set above the leasing source 4 2 Storage transportation Facilities 4 2 1 For the storage tank used for liquefied hydrocarbons or liquids of Class Ab the detectors should be set in the following positions 1 A detector per 30m should be set inside the firewall of the liquefied hydrocarbon tank group and the distance between the detector and the flange or valve of the drain outlet or bottom connection pipe of the tank should not be longer than 15m 2 Inside the firewall of the liquids of Class Ab a or more detector s should be set and the distance between the detector and the flange or valve of the tank drain outlet sampling port or bottom side connection pipe should not be longer than 15 m 4 2 2 For the handling facilities used for liquefied hydrocarbons or the liquids of Class Ab a or more detector s should be set at the following positions 1 For the railroad platform equipped with small filling risers a detector is set for every tank wagon length preferably and the horizontal distance between the detector and the inlet of the wagon should not be longer than 15 m 2 For the railroad platform equipped with big filling risers a detector is set preferably 3 The horizontal distance between the position filling tank car and the filling riser in an automobile handling station should not be longer than 15 m The detector should be located in accordance with the stipulation in for Clause 4 1 2 of the Specifications when there is a surge tank in the automobile handling station 4 2 3 Detectors for the pumps and compressors of the handling facilities should be set in accordance with the stipulations in for Clauses 4 1 1 through 4 1 3 of the Specifications 7 4 2 4 Detectors in the filling station of liquefied hydrocarbons should be set in accordance with the following requirements 1 For completely or partially closed cylinder filling workshop the distance between the filling port and the detector should be within the range of 5 7 5m 2 The completely or partially closed cylinder warehouse should accord with the stipulations in for Clause 4 1 3 of the Specifications Around the warehouse partially in the open air a detector should be set per 15 30ml one detector should be set when the circumference is longer than 15 m 3 The distance between the detector and the drain outlet or valve group of the surge tank should be within the range of 5 7 5 m 4 2 5 For the completely or partially enclosed workshop to fill hydrogen cylinders the detectors should be set in the highest point above the filling port where the gas easily stays indoor 4 2 6 For the docks to handle liquefied hydrocarbons liquids of Classes Ab and Ba a detector should be set in the horizontal area of 15 m radius from the transferring arm When the detector cannot be set so the detection of the combustible gases should accord with the stipulations in for Clause 3 0 9 of the Specifications 4 2 7 Toxic gas detectors used for toxic gas storage and transportation facilities should be set in accordance with the stipulations in for Clauses 4 1 2 and 4 1 3 4 3 Locations where Combustible Gases and Toxic Gases Diffuse and Accumulate 4 3 1 The detector or detectors should be set in a point 5m from the fired heater or outside the firewall between the heater and the equipment for the gases of Class A and liquefied hydrocarbons or a probable releasing sources in the case of abnormal running 4 3 2 A detector should be set in the control room and power distribution room as well as places within 30 m from the processing equipment set or storage transportation for the gases Class A toxic gases liquefied hydrocarbons and the liquids of Class Ab meeting the following conditions 1 The door or window of the room faces the processing equipment set or storage transportation facilities 2 The control room or power distribution room where the overground power cable troughs or tubes and pipelines for the instrument enter 4 3 3 A detector should be set in the non explosion proof online instrument cubicle located within Region 2 For detection of the combustible gas lighter than air the detector should be set the highest point where the combustible gases easily accumulate in the instrument cubicle 4 3 4 Detectors should be set on those spots out of the effectively detectable coverage of the detector 1 The lowest ground of pit and or sewage ditch where the combustible gases and or toxic 8 gas may accumulate in the area of the processing unit or storage transportation facilities which use or generate liquefied hydrocarbons and or toxic gases 2 The corner pockets where the gases of Class A toxic gases easily accumulate 5 DETECTION ALARM SYSTEMS OF COMBUSTIBLE GASES AND TOXIC GASES 5 1 System Composition and Performance 5 1 1 Such a system should be a combustible gas alert instrument consisting either of a detector and an alarm of combustible gas or toxic gas or of a detector and a indicator alarm of combustible gas or toxic gas as its essential part Besides it also may be a detection and alarm system consisting of a special data acquisition system and a detector 5 1 2 The system composition should meet the following requirements 1 For the detector that adopts mV signal frequency signal or 4 20mA signal as its output it is recommended to use an indicator alarm as its special alarm controller a alarm consisting of a signal setter and a flash alarm unit also may be used the signal to the interlocking protection system and the alarm recorder preferably comes from the alarm controller or the signal setter 2 For the detector adopting contact output mode it is recommended to connect the alarm signal to the flash alarm system or the interlocking protection system and output of the signal to the alarm recorder may be realized by the flash alarm system or the interlocking protection system 3 It is recommended to adopt a special data acquisition unit or device as the data acquisition system of a combustible gas and or a toxic gas and it is unsuitable to connect a detector used for a combustible gas and or a toxic to some other signal acquisition unit or device consequently mutual substitution between both the acquisition units or devices must be avoided 5 1 3 When the signal setter and the alarm controller are adopted the alarm recorder should be set in accordance with the stipulation in for Clause 3 0 3 of the Specifications and the alarm recorder should have both alarm printing and history data storing functions The alarm recorder may be a DCS or some other data acquisition system or a selected special industrial microcomputer or system 5 1 4 Tec