Our focus for this lunch and learn is an introduction to common mistakes identified in fire sizing equations for PSVs in the upstream and midstream industries. We’ll briefly touch on the assumptions in the API 521 equations for a pool fire, when not to use these equations, and the most common mistakes for vessels inside of buildings, or in areas without good drainage. We will then focus on methods where API 521 recommends for “time-dependent analysis” of fire sizing a PSV, including but not limited to:
Changes in liquid level & wetted area
Examples of how latent heat values change during a fire
Which latent heats to use from a simulator (non-obvious)
How the PSV size required significant changes during the course of a fire on a vessel
One or two software tools that are common to use in industry for fire sizing a PSV
This document discusses pressure relief systems, which are critical in the chemical process industries to safely handle overpressurization. It describes causes of overpressurization, types of safety valves and rupture disks used for relief, and components of open and closed pressure relief systems. Open systems vent non-hazardous gases to the atmosphere, while closed systems route flammable gases through flare headers and knockout drums to be burned in a flare stack. The document provides example calculations for sizing relief valves, piping, and other components to ensure systems can safely relieve pressure without resealing valves.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It defines important terminology related to PSVs and describes the types and operating principles of conventional, balanced bellow, and pilot-operated PSVs. The document outlines the procedure for early PSV sizing, including identifying capacity requirements, applicable standards, and inter-discipline interfaces. It also notes lessons learned regarding material selection and potential failure modes of bellow-type PSVs.
This document discusses overpressure scenarios and required relief rates for process equipment. It identifies key data needed for the analysis such as P&IDs and equipment specifications. Common overpressure scenarios are described such as fires, control valve failures, thermal expansion, and utility failures. Industry guidelines for analyzing these scenarios are presented. Methods for determining applicable scenarios, calculating relief rates, and addressing special cases like gas blowby are outlined. The document stresses being conservative in initial analysis and reviewing all relevant guidelines.
Pressure Relief Valve Sizing for Single Phase FlowVikram Sharma
This presentation file provides a quick refresher to pressure relief valve sizing for single phase flow. The calculation guideline is as per API Std 520.
- The document discusses sizing pressure safety valves (PSVs) for oil and gas facilities.
- It covers PSV types, causes of chattering, and outlines the step-by-step process for sizing calculations including developing relief scenarios, determining required relief areas, and selecting valve sizes.
- Relief scenarios considered include blocked outlets, thermal expansion, tube rupture, gas blow-by, inlet valve failure, and exterior fires. Relief calculations involve assessing single-phase, two-phase, and transient relief situations.
Ai Ch E Overpressure Protection Trainingernestvictor
The document provides an overview of overpressure protection and relief system design. It discusses key concepts such as causes of overpressure, applicable codes and standards, the relief system design process, relief device terminology, and methods for determining relief loads from scenarios such as blocked outlets, thermal expansion, external fires, and automatic control failures. The document is intended to educate engineers on important considerations for properly sizing and designing pressure relief systems.
Safety valves are automatic pressure relief devices that prevent excessive pressure buildup in systems like reactors, pipelines, and compressors. They open rapidly when pressure exceeds the set point to safely release pressure and reclose once normal pressure is restored. Proper safety valve design and sizing according to codes like API 520 and 526 is critical to ensure the valve can relieve the required flow rate without overpressurizing equipment. Key parameters include pressure conditions, required flow rate, orifice area, and type of valve.
The document summarizes the basics of pressure relief devices, including why they are required, common components, classification and types. It provides examples of relief scenarios and causes of overpressure. The key steps in relief device sizing calculations are outlined. An example calculation is shown for checking the adequacy of installed relief devices for a reactor system during an emergency relief scenario involving an external fire.
This document discusses pressure relief systems, which are critical in the chemical process industries to safely handle overpressurization. It describes causes of overpressurization, types of safety valves and rupture disks used for relief, and components of open and closed pressure relief systems. Open systems vent non-hazardous gases to the atmosphere, while closed systems route flammable gases through flare headers and knockout drums to be burned in a flare stack. The document provides example calculations for sizing relief valves, piping, and other components to ensure systems can safely relieve pressure without resealing valves.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It defines important terminology related to PSVs and describes the types and operating principles of conventional, balanced bellow, and pilot-operated PSVs. The document outlines the procedure for early PSV sizing, including identifying capacity requirements, applicable standards, and inter-discipline interfaces. It also notes lessons learned regarding material selection and potential failure modes of bellow-type PSVs.
This document discusses overpressure scenarios and required relief rates for process equipment. It identifies key data needed for the analysis such as P&IDs and equipment specifications. Common overpressure scenarios are described such as fires, control valve failures, thermal expansion, and utility failures. Industry guidelines for analyzing these scenarios are presented. Methods for determining applicable scenarios, calculating relief rates, and addressing special cases like gas blowby are outlined. The document stresses being conservative in initial analysis and reviewing all relevant guidelines.
Pressure Relief Valve Sizing for Single Phase FlowVikram Sharma
This presentation file provides a quick refresher to pressure relief valve sizing for single phase flow. The calculation guideline is as per API Std 520.
- The document discusses sizing pressure safety valves (PSVs) for oil and gas facilities.
- It covers PSV types, causes of chattering, and outlines the step-by-step process for sizing calculations including developing relief scenarios, determining required relief areas, and selecting valve sizes.
- Relief scenarios considered include blocked outlets, thermal expansion, tube rupture, gas blow-by, inlet valve failure, and exterior fires. Relief calculations involve assessing single-phase, two-phase, and transient relief situations.
Ai Ch E Overpressure Protection Trainingernestvictor
The document provides an overview of overpressure protection and relief system design. It discusses key concepts such as causes of overpressure, applicable codes and standards, the relief system design process, relief device terminology, and methods for determining relief loads from scenarios such as blocked outlets, thermal expansion, external fires, and automatic control failures. The document is intended to educate engineers on important considerations for properly sizing and designing pressure relief systems.
Safety valves are automatic pressure relief devices that prevent excessive pressure buildup in systems like reactors, pipelines, and compressors. They open rapidly when pressure exceeds the set point to safely release pressure and reclose once normal pressure is restored. Proper safety valve design and sizing according to codes like API 520 and 526 is critical to ensure the valve can relieve the required flow rate without overpressurizing equipment. Key parameters include pressure conditions, required flow rate, orifice area, and type of valve.
The document summarizes the basics of pressure relief devices, including why they are required, common components, classification and types. It provides examples of relief scenarios and causes of overpressure. The key steps in relief device sizing calculations are outlined. An example calculation is shown for checking the adequacy of installed relief devices for a reactor system during an emergency relief scenario involving an external fire.
Pressure relief devices are important safety components that protect process equipment from overpressure. Standards like the ASME Boiler and Pressure Vessel Code provide guidelines for the proper design, installation, and sizing of relief valves, rupture disks, and other pressure relief devices. These standards help ensure personnel safety and prevent equipment damage in the event excess pressure develops from sources like explosions, fires, or pump failures.
This document outlines a continuing education course on overpressure protection and relief system design. The course contents include an introduction to relief systems, applicable codes and standards, the work process for relief system design, relief device terminology, and causes of overpressure and determining relief loads. The presentation provides information on different types of relief devices, relief system discharge configurations, references and codes, and the multi-step design process and required design data. Key relief device terminology is also defined.
This document discusses pressure relief systems. It begins by defining pressure relief events and overpressure hazards. It then outlines potential lines of defense like inherently safe design, passive control, and installing relief systems. The document goes on to define relief systems and explain why they are used. It provides terminology and code requirements related to relief systems. The bulk of the document is focused on the methodology for designing relief systems, including locating reliefs, choosing device types, developing scenarios, sizing reliefs through calculations, choosing a worst case, and designing the full relief system. It emphasizes the importance of proper installation, inspection, and maintenance of relief systems.
Pressure Safety Valve Sizing - API 520/521/526Vijay Sarathy
No chemical process facility is immune to the risk of overpressure to avoid dictating the necessity for overpressure protection. For every situation that demands safe containment of process gas, it becomes an obligation for engineers to equally provide pressure relieving and flaring provisions wherever necessary. The levels of protection are hierarchical, starting with designing an inherently safe process to avoid overpressure followed by providing alarms for operators to intervene and Emergency Shutdown provisions through ESD and SIL rated instrumentation. Beyond these design and instrument based protection measures, the philosophy of containment and abatement steps such as pressure relieving devices, flares, physical dikes and Emergency Response Services is employed
Accumulation and Over-pressure: difference between accumulation and overpressureVarun Patel
Accumulation is pressure above the maximum allowable working pressure that vessel experience during high pressure event. Hence, when we say ‘accumulation’, its mean we are talking about the vessel or equipment.
On the other hand, Overpressure is pressure above the set pressure of the pressure safety valve that PSV experience during high pressure event. Hence, when we say ‘accumulation’, its mean we are talking about the pressure relief valve.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It discusses important terminologies, types of PSVs, sizing basis, applicable standards, and the early sizing procedure. The procedure involves selecting possible orifice areas to meet capacity requirements. The objectives of early sizing are to remove holds in piping and instrumentation diagrams and allow early release of piping designs. The document also discusses inter-discipline interfaces, lessons learned, and quality management system documents related to PSV sizing.
This document discusses simulation of an aspen flare system using Aspen Flare System Analyzer software. It describes defining the composition, flare network scheme, sources such as control valves and pressure safety valves, and scenarios to simulate, such as all relief devices activating. The outcomes of the simulation can be used to design and verify the flare header size and other parameters meet API standards. The simulation aims to size the flare system and verify its performance under different operating conditions.
1. The document discusses procedures for calculating pressure safety valve (PSV) sizes for various scenarios that could lead to overpressure. It covers scenarios like closed outlets, external fires, control valve failures, hydraulic expansion, heat exchanger tube ruptures, and power or cooling failures.
2. Calculation methods include enthalpy balances for fractionating columns and the use of relief equations specified in codes like API 521. Worst cases are chosen from all possible scenarios to determine the required PSV size.
3. Key scenarios discussed in detail include closed outlets on vessels, external fires, failures of automatic controls, hydraulic expansion, heat exchanger tube ruptures, total and partial power failures, reflux losses,
Sizing of relief valves for supercritical fluidsAlexis Torreele
The document provides an overview of Jacobs, an engineering company, and discusses their approach to sizing relief valves for supercritical fluids. It then presents a case study example of calculating the relief requirements for a vessel containing methane undergoing an external fire. The key steps involve: (1) gathering process data; (2) determining heat input from the fire; (3) calculating fluid properties as temperature increases; (4) determining mass and volume relief rates; (5) calculating choked flow rates; and (6) sizing the required relief valve orifice. The example demonstrates that relief of supercritical fluids can involve complex two-phase flow that requires specialized modeling approaches.
The document discusses various scenarios that could lead to overpressure in vessels and equipment and the procedures to calculate the size of pressure safety valves (PSVs) to prevent overpressure. It describes scenarios like closed outlets, external fires, failure of automatic controls, hydraulic expansion, heat exchanger tube ruptures, power failures, and more. It provides methods to calculate the relief rates needed for PSVs using equations, charts, and procedures outlined in design codes like ASME and API standards. The goal is to size PSVs correctly to ensure accumulated pressure stays below the maximum allowable to maintain safety.
The document discusses the design of emergency relief systems for exothermic batch reactors. It covers key components of a relief system including pressure relief devices, piping and headers, containment systems, and treatment systems. It also discusses models for sizing relief devices, including vessel and vent flow models as well as heat models. The CHEMCAD software is identified as a useful tool for designing relief systems and sizing relief devices.
This document summarizes API STD 521 Part-I, which provides guidance on overpressure protection for refinery equipment. It discusses overpressure causes and protection philosophies. It also lists the minimum recommended contents for relief system designs and flare header calculations. These include analyzing overpressure causes, operating conditions, relief device sizing, and documentation of simulation inputs and outputs. Various overpressure causes are outlined, such as closed outlets, absorbent or cooling failures, accumulation of non-condensables, abnormal heat input, explosions, and depressurizing. Protection measures against these causes like relief valves, rupture disks, and explosion prevention are also mentioned.
The document discusses sizing calculations for pressure safety valves (PSVs). It begins with introductions to relief systems, definitions of key terms like set pressure and accumulation. It then describes different types of PSVs and issues like chattering. The document outlines the steps for sizing calculations, which include developing a process safety diagram and relief scenarios. It provides examples of relief scenarios like blocked outlet, thermal expansion, and tube rupture. The goal of the document is to provide guidance on properly performing PSV sizing calculations.
This presentation covers process safety considerations and when a dynamic simulation is required. We also provide a modelling approach and a case study on Coker Bottoms Steam Generator, which includes information on device selection and device sizing.
Safety is the most important factor in designing a process system. Some undesired conditions might happen leading to damage in a system. Control systems might be installed to prevent such conditions, but a second safety device is also needed. One kind of safety device which is commonly used in the processing industry is the relief valve. A relief valve is a type of valve to control or limit the pressure in a system by allowing the pressurised fluid to flow out from the system.
Oil & Gas Pipelines are often subjected to an operation called ‘Pigging’ for maintenance purposes (For e.g., cleaning the pipeline of accumulated liquids or waxes). A pig is launched from a pig launcher that scrapes out the remnant contents of the pipeline into a vessel known as a ‘Slug catcher’. The term slug catcher is used since pigging operations produces a Slug flow regime characterized by the alternating columns of liquids & gases. Slug catcher’s are popularly of two types – Horizontal Vessel Type & Finger Type Slug catcher. However irrespective of the type used, the determination of the slug catcher volume becomes the primary step before choosing the slug catcher type.
This document provides definitions and information related to fire and explosion hazards. It defines key terms like hazard, risk, fire, explosion, ignition sources, and stages of combustion. It also discusses flash point, fire point, auto-ignition temperature, and flammability limits. The document outlines how to prevent and mitigate explosions through ventilation, ignition source control, containment, material substitution, and separation. It also discusses hazardous area classification and electrical equipment certification for different zones and gas/vapor groups.
The document summarizes key differences between the 5th and 6th editions of API-2000 standards for venting of atmospheric storage tanks. Some significant differences include:
- The 6th edition includes the EN 14015 venting model which can calculate higher venting loads than the API 2000 model.
- The 6th edition includes a new section on mitigating risks of internal deflagration in tanks.
- Recent experiments show flame propagation through pressure/vacuum valves is possible, inconsistent with statements in the 5th edition.
- Refrigerated tank venting requirements were re-written based on other standards instead of just hexane.
- New section provides consistency in testing venting device capacities
Excel sheet Download Link: https://www.scribd.com/document/385945712/PSV-Sizing-Tool-API-Based-Calc-Sheets
PSV Sizing for Blocked Liquid Discharge Condition
PSV Sizing for Blocked Gas Discharge Condition
PSV Sizing for Fire Case of Liquid Filled Vessel
PSV Sizing for Control Valve Fail Open Case
Relief Valve Sizing for Thermal Expansion
Restriction Orifice Sizing for Gas Flow
Restriction Orifice Sizing for Liquid Flow
Single Phase Flow Line Sizing Tool
Gas Control Valve Sizing Tool
Process furnaces are widely used in petroleum refineries and petrochemical plants to generate heat through the combustion of fuels. This heat is transferred to process fluids inside coil tubes and can range from a few thousand to a few million MW. Common applications include crude distillation units and reaction heaters containing catalysts. Furnaces come in various designs like vertical cylindrical, box type, or cabin furnaces and must maximize heat transfer while minimizing emissions and fuel consumption. Burners, refractory, insulation and controls are important components that require consideration for optimal furnace performance.
Guidelines for Engineering Design for Process Safety (Process Safety Guidelin...gurkanarifyalcinkaya
This document discusses pressure relief systems and emergency relief device design. It describes various scenarios that can lead to overpressure such as fires, blocked outlets, operational failures of equipment or utilities, and process upsets. These scenarios include fires, blocked flow, cooling water or power failure, and equipment malfunctions. The document emphasizes that relief systems should be designed to safely handle any scenarios that could cause overpressure while minimizing the need for relief devices to actuate. Regulations and industry standards provide guidelines for relief system design.
CHEN401 - Tutorial 1 - Review on Physical & Chemical Properties & Classificat...AdhamAyman5
Petroleum, or crude oil, is a naturally occurring mixture of hydrocarbons and other organic compounds. It is formed from the remains of ancient organisms buried underground that are subjected to heat and pressure over long periods of time. Crude oil consists mainly of hydrocarbons such as alkanes, cycloalkanes, and aromatics, along with some impurities like sulfur, nitrogen, and oxygen compounds. The properties of crude oil, such as specific gravity, color, odor, viscosity, and boiling point range, depend on its chemical composition and can help characterize the oil. During the refining process, crude oil is separated into fractions and purified to produce useful petroleum products like gasoline, diesel and others.
Pressure relief devices are important safety components that protect process equipment from overpressure. Standards like the ASME Boiler and Pressure Vessel Code provide guidelines for the proper design, installation, and sizing of relief valves, rupture disks, and other pressure relief devices. These standards help ensure personnel safety and prevent equipment damage in the event excess pressure develops from sources like explosions, fires, or pump failures.
This document outlines a continuing education course on overpressure protection and relief system design. The course contents include an introduction to relief systems, applicable codes and standards, the work process for relief system design, relief device terminology, and causes of overpressure and determining relief loads. The presentation provides information on different types of relief devices, relief system discharge configurations, references and codes, and the multi-step design process and required design data. Key relief device terminology is also defined.
This document discusses pressure relief systems. It begins by defining pressure relief events and overpressure hazards. It then outlines potential lines of defense like inherently safe design, passive control, and installing relief systems. The document goes on to define relief systems and explain why they are used. It provides terminology and code requirements related to relief systems. The bulk of the document is focused on the methodology for designing relief systems, including locating reliefs, choosing device types, developing scenarios, sizing reliefs through calculations, choosing a worst case, and designing the full relief system. It emphasizes the importance of proper installation, inspection, and maintenance of relief systems.
Pressure Safety Valve Sizing - API 520/521/526Vijay Sarathy
No chemical process facility is immune to the risk of overpressure to avoid dictating the necessity for overpressure protection. For every situation that demands safe containment of process gas, it becomes an obligation for engineers to equally provide pressure relieving and flaring provisions wherever necessary. The levels of protection are hierarchical, starting with designing an inherently safe process to avoid overpressure followed by providing alarms for operators to intervene and Emergency Shutdown provisions through ESD and SIL rated instrumentation. Beyond these design and instrument based protection measures, the philosophy of containment and abatement steps such as pressure relieving devices, flares, physical dikes and Emergency Response Services is employed
Accumulation and Over-pressure: difference between accumulation and overpressureVarun Patel
Accumulation is pressure above the maximum allowable working pressure that vessel experience during high pressure event. Hence, when we say ‘accumulation’, its mean we are talking about the vessel or equipment.
On the other hand, Overpressure is pressure above the set pressure of the pressure safety valve that PSV experience during high pressure event. Hence, when we say ‘accumulation’, its mean we are talking about the pressure relief valve.
This document provides an overview of early sizing considerations for pressure safety valves (PSVs). It discusses important terminologies, types of PSVs, sizing basis, applicable standards, and the early sizing procedure. The procedure involves selecting possible orifice areas to meet capacity requirements. The objectives of early sizing are to remove holds in piping and instrumentation diagrams and allow early release of piping designs. The document also discusses inter-discipline interfaces, lessons learned, and quality management system documents related to PSV sizing.
This document discusses simulation of an aspen flare system using Aspen Flare System Analyzer software. It describes defining the composition, flare network scheme, sources such as control valves and pressure safety valves, and scenarios to simulate, such as all relief devices activating. The outcomes of the simulation can be used to design and verify the flare header size and other parameters meet API standards. The simulation aims to size the flare system and verify its performance under different operating conditions.
1. The document discusses procedures for calculating pressure safety valve (PSV) sizes for various scenarios that could lead to overpressure. It covers scenarios like closed outlets, external fires, control valve failures, hydraulic expansion, heat exchanger tube ruptures, and power or cooling failures.
2. Calculation methods include enthalpy balances for fractionating columns and the use of relief equations specified in codes like API 521. Worst cases are chosen from all possible scenarios to determine the required PSV size.
3. Key scenarios discussed in detail include closed outlets on vessels, external fires, failures of automatic controls, hydraulic expansion, heat exchanger tube ruptures, total and partial power failures, reflux losses,
Sizing of relief valves for supercritical fluidsAlexis Torreele
The document provides an overview of Jacobs, an engineering company, and discusses their approach to sizing relief valves for supercritical fluids. It then presents a case study example of calculating the relief requirements for a vessel containing methane undergoing an external fire. The key steps involve: (1) gathering process data; (2) determining heat input from the fire; (3) calculating fluid properties as temperature increases; (4) determining mass and volume relief rates; (5) calculating choked flow rates; and (6) sizing the required relief valve orifice. The example demonstrates that relief of supercritical fluids can involve complex two-phase flow that requires specialized modeling approaches.
The document discusses various scenarios that could lead to overpressure in vessels and equipment and the procedures to calculate the size of pressure safety valves (PSVs) to prevent overpressure. It describes scenarios like closed outlets, external fires, failure of automatic controls, hydraulic expansion, heat exchanger tube ruptures, power failures, and more. It provides methods to calculate the relief rates needed for PSVs using equations, charts, and procedures outlined in design codes like ASME and API standards. The goal is to size PSVs correctly to ensure accumulated pressure stays below the maximum allowable to maintain safety.
The document discusses the design of emergency relief systems for exothermic batch reactors. It covers key components of a relief system including pressure relief devices, piping and headers, containment systems, and treatment systems. It also discusses models for sizing relief devices, including vessel and vent flow models as well as heat models. The CHEMCAD software is identified as a useful tool for designing relief systems and sizing relief devices.
This document summarizes API STD 521 Part-I, which provides guidance on overpressure protection for refinery equipment. It discusses overpressure causes and protection philosophies. It also lists the minimum recommended contents for relief system designs and flare header calculations. These include analyzing overpressure causes, operating conditions, relief device sizing, and documentation of simulation inputs and outputs. Various overpressure causes are outlined, such as closed outlets, absorbent or cooling failures, accumulation of non-condensables, abnormal heat input, explosions, and depressurizing. Protection measures against these causes like relief valves, rupture disks, and explosion prevention are also mentioned.
The document discusses sizing calculations for pressure safety valves (PSVs). It begins with introductions to relief systems, definitions of key terms like set pressure and accumulation. It then describes different types of PSVs and issues like chattering. The document outlines the steps for sizing calculations, which include developing a process safety diagram and relief scenarios. It provides examples of relief scenarios like blocked outlet, thermal expansion, and tube rupture. The goal of the document is to provide guidance on properly performing PSV sizing calculations.
This presentation covers process safety considerations and when a dynamic simulation is required. We also provide a modelling approach and a case study on Coker Bottoms Steam Generator, which includes information on device selection and device sizing.
Safety is the most important factor in designing a process system. Some undesired conditions might happen leading to damage in a system. Control systems might be installed to prevent such conditions, but a second safety device is also needed. One kind of safety device which is commonly used in the processing industry is the relief valve. A relief valve is a type of valve to control or limit the pressure in a system by allowing the pressurised fluid to flow out from the system.
Oil & Gas Pipelines are often subjected to an operation called ‘Pigging’ for maintenance purposes (For e.g., cleaning the pipeline of accumulated liquids or waxes). A pig is launched from a pig launcher that scrapes out the remnant contents of the pipeline into a vessel known as a ‘Slug catcher’. The term slug catcher is used since pigging operations produces a Slug flow regime characterized by the alternating columns of liquids & gases. Slug catcher’s are popularly of two types – Horizontal Vessel Type & Finger Type Slug catcher. However irrespective of the type used, the determination of the slug catcher volume becomes the primary step before choosing the slug catcher type.
This document provides definitions and information related to fire and explosion hazards. It defines key terms like hazard, risk, fire, explosion, ignition sources, and stages of combustion. It also discusses flash point, fire point, auto-ignition temperature, and flammability limits. The document outlines how to prevent and mitigate explosions through ventilation, ignition source control, containment, material substitution, and separation. It also discusses hazardous area classification and electrical equipment certification for different zones and gas/vapor groups.
The document summarizes key differences between the 5th and 6th editions of API-2000 standards for venting of atmospheric storage tanks. Some significant differences include:
- The 6th edition includes the EN 14015 venting model which can calculate higher venting loads than the API 2000 model.
- The 6th edition includes a new section on mitigating risks of internal deflagration in tanks.
- Recent experiments show flame propagation through pressure/vacuum valves is possible, inconsistent with statements in the 5th edition.
- Refrigerated tank venting requirements were re-written based on other standards instead of just hexane.
- New section provides consistency in testing venting device capacities
Excel sheet Download Link: https://www.scribd.com/document/385945712/PSV-Sizing-Tool-API-Based-Calc-Sheets
PSV Sizing for Blocked Liquid Discharge Condition
PSV Sizing for Blocked Gas Discharge Condition
PSV Sizing for Fire Case of Liquid Filled Vessel
PSV Sizing for Control Valve Fail Open Case
Relief Valve Sizing for Thermal Expansion
Restriction Orifice Sizing for Gas Flow
Restriction Orifice Sizing for Liquid Flow
Single Phase Flow Line Sizing Tool
Gas Control Valve Sizing Tool
Process furnaces are widely used in petroleum refineries and petrochemical plants to generate heat through the combustion of fuels. This heat is transferred to process fluids inside coil tubes and can range from a few thousand to a few million MW. Common applications include crude distillation units and reaction heaters containing catalysts. Furnaces come in various designs like vertical cylindrical, box type, or cabin furnaces and must maximize heat transfer while minimizing emissions and fuel consumption. Burners, refractory, insulation and controls are important components that require consideration for optimal furnace performance.
Guidelines for Engineering Design for Process Safety (Process Safety Guidelin...gurkanarifyalcinkaya
This document discusses pressure relief systems and emergency relief device design. It describes various scenarios that can lead to overpressure such as fires, blocked outlets, operational failures of equipment or utilities, and process upsets. These scenarios include fires, blocked flow, cooling water or power failure, and equipment malfunctions. The document emphasizes that relief systems should be designed to safely handle any scenarios that could cause overpressure while minimizing the need for relief devices to actuate. Regulations and industry standards provide guidelines for relief system design.
CHEN401 - Tutorial 1 - Review on Physical & Chemical Properties & Classificat...AdhamAyman5
Petroleum, or crude oil, is a naturally occurring mixture of hydrocarbons and other organic compounds. It is formed from the remains of ancient organisms buried underground that are subjected to heat and pressure over long periods of time. Crude oil consists mainly of hydrocarbons such as alkanes, cycloalkanes, and aromatics, along with some impurities like sulfur, nitrogen, and oxygen compounds. The properties of crude oil, such as specific gravity, color, odor, viscosity, and boiling point range, depend on its chemical composition and can help characterize the oil. During the refining process, crude oil is separated into fractions and purified to produce useful petroleum products like gasoline, diesel and others.
A student technical seminar on the use of condensing economisers used in thermal power industry and the need to increase their use for lesser carbon footprint.
This document contains information about a refrigeration and air conditioning (RAC) course, including lesson objectives, recaps of topics like latent and sensible heat, diagrams of vapor compression cycles and phase changes, and diagrams labeling RAC system components. It discusses concepts like superheat, subcooled liquid, where latent and sensible heat occur in RAC systems, and lists components like the compressor, condenser, evaporator, expansion device, and others. The document aims to teach students about heat transfer and vapor compression cycles in RAC systems through definitions, diagrams, and a labeling activity.
The document discusses propane safety issues arising from tropical storm Irene that hit Connecticut. Large propane tanks were tipped over or washed into Long Island Sound, creating environmental and safety concerns. It also discusses regulations for propane storage and installation from NFPA 58, including container requirements, installation of aboveground cylinders, and underground container installation. Proper testing and safety precautions are needed when working with propane due to its heavier-than-air properties.
This document provides information on fire network design, including definitions of fire terms, classes of fire, extinguishing methods and agents, passive and active fire protection systems, and considerations for firefighting system design. It discusses water capacity and rates, sources of water, fire pumps, and piping design for firewater distribution systems. The key aspects covered are fire protection philosophy, sizing systems based on the largest single fire scenario, and maintaining adequate water pressure and flow rates throughout the network.
This document discusses gas turbine fuel flexibility and the use of different fuel sources like LNG. It notes that customers are concerned about gas interchangeability and flexibility given changes like increased LNG imports. The document covers different fuel types and properties, technologies for fuel delivery, and how gas turbine designs impact fuel flexibility and emissions. It analyzes factors like the Wobbe index, hydrocarbon dew point, and fuel composition that influence interchangeability and equipment operability.
Richard Gallagher of Zurich presented the keynote presentation at the Fire Protection Research Foundation’s SUPDET 2010 conference in Orlando on February 18, 2010. Mr. Gallagher summarized presentations of seven leading engineering firms who offered their ideas on how best to protect a high challenge warehouse from fire.
On February 18, 2010, Richard Gallagher of Zurich presented the keynote presentation at the Fire Protection Research Foundation’s SUPDET 2010 event where he summarized the presentations of the previous day. Seven leading engineering firms presented their ideas on how best to protect a high challenge warehouse from fire.
The document provides an overview of lead free vapor phase reflow soldering. It discusses the basics, including understanding component variation, recommended time and temperature profiles, and how vapor phase technology ensures temperatures remain within specifications. The history of vapor phase is summarized, followed by explanations of how it works and how it addresses past challenges like tombstoning and environmental concerns. Solutions are presented for automation, throughput and maintaining consistent low temperatures compared to convection.
Fire protection systems are required to ensure safety from potential fire hazards in buildings. A document outlines various fire sources and describes different types of fire suppression agents like water, carbon dioxide, halon, foam, powder and sand. It also discusses types of fires and fire protection system components like sprinklers, risers and design criteria for sprinkler systems based on hazard classification. Shop drawings are detailed drawings used to guide construction, showing pipe sizes, dimensions and details coordinated with other building services.
This document provides an overview of a fire protection training session at QPS in Vadodara, India. It introduces the trainer, Abhijit Haldankar, who has over 25 years of experience in process and environmental safety. The agenda covers fire basics, regulations and standards, fire protection system design, fire water demand calculations, fire water pumps, and other fire protection topics. A recent fire incident at an FRP coating company is also described, where a fire started in a sheet metal coating machine and spread to a nearby resin storage area.
The document discusses regulations and safety concerns regarding propane tanks and liquefied petroleum gas (LPG) in Connecticut following tropical storm Irene. It notes that many homes along the Connecticut shoreline were damaged by the storm and large propane tanks were tipped over or washed away, posing environmental and safety risks. It also summarizes portions of NFPA 58, which sets standards for LPG storage, use, handling and transportation, including chapters on container requirements, installation standards, and annexes providing additional explanatory material.
Heavy Oil recovery traditionally starts with depletion drive and (natural) waterdrive with very low recoveries as a result. As EOR technique, steam injection has been matured since the 1950s using CSS (cyclic steam stimulation), steam drive or steam flooding, and SAGD (steam assisted gravity drainage). The high energy cost of heating up the oil bearing formation to steam temperature and the associated high CO2 footprint make steam based technology less attractive today and many companies in the industry have been actively trying to find alternatives or improvements. As a result there are now many more energy efficient recovery technologies that can unlock heavy oil resources compared with only a decade ago. This presentation will discuss breakthrough alternatives to steam based recovery as well as incremental improvement options to steam injection techniques. The key message is the importance to consider these techniques because steam injection is costly and has a high CO2 footprint
Johan van Dorp holds an MSc in Experimental Physics from Utrecht University and joined Shell in 1981. He has served on several international assignments, mainly in petroleum and reservoir engineering roles. He recently led the extra heavy-oil research team at the Shell Technology Centre in Calgary, focusing on improved in-situ heavy-oil recovery technologies. Van Dorp also was Shell Group Principal Technical Expert in Thermal EOR and has been involved with most thermal projects in Shell throughout the world, including in California, Oman, the Netherlands, and Canada. He retired from Shell after more than 35 years in Oct 2016. Van Dorp (co-)authored 13 SPE papers on diverse subjects.
This document provides an overview of combustion and rocket nozzle flow for a course on rocket and mission analysis. It discusses key equations governing combustion chamber exit velocity and how operating rockets fuel-rich or lean can impact performance. Examples are provided on calculating combustion chamber temperature and dissociation of products using NASA's CEA program for hydrogen-oxygen combustion. The document aims to build understanding of combustion thermochemistry and nozzle flow concepts.
This is presentation given by PG&E representatives about a large Liquified Natural Gas (LNG) project being developed in Felton, CA. This project is one of the largest ever developed in the industry.
A Boiling Liquid Expanding Vapor Explosion (BLEVE) occurs when a pressurized liquid-containing vessel is exposed to high heat and ruptures catastrophically. When the vessel fails, debris can travel hundreds of feet with tremendous force and the escaping fuel can ignite, causing an expanding fireball. BLEVEs pose serious hazards and require large evacuation distances due to potential blast effects and projectiles. Emergency responders should control LP gas leaks and fires by stopping gas flow if possible, diluting vapors to prevent ignition, and cooling exposed vessels to prevent BLEVEs.
Developing Fit-for-Purpose Solutions: Gas Coolers - G. Dal Belin Peruffo - Al...Centro Studi Galileo
The document discusses CO2 gas coolers and their advantages over traditional HFC outdoor units. It provides an overview of gas cooler design considerations like high pressure requirements, single-phase fluid behavior at high air temperatures, and methods to reduce thermal bypassing. These include symmetrical tubing circuits, slits between tube rows, and future developments like inner grooved copper-iron alloy tubes. The document emphasizes Alfa Laval's laboratory testing and data collection to optimize gas cooler performance and ensure it through the Eurovent certification process.
Mark Rice - Planning for Emergency Mass-Depopulation of Swine in Response to ...John Blue
Planning for Emergency Mass-Depopulation of Swine in Response to a Foreign Animal Disease Outbreak - Mark Rice, North Carolina State University, from the 2015 World Pork Expo, June 3 - 5, 2015, Des Moines, IA, USA.
More presentations at http://www.swinecast.com/2015-world-pork-expo
Optimizing Gradle Builds - Gradle DPE Tour Berlin 2024Sinan KOZAK
Sinan from the Delivery Hero mobile infrastructure engineering team shares a deep dive into performance acceleration with Gradle build cache optimizations. Sinan shares their journey into solving complex build-cache problems that affect Gradle builds. By understanding the challenges and solutions found in our journey, we aim to demonstrate the possibilities for faster builds. The case study reveals how overlapping outputs and cache misconfigurations led to significant increases in build times, especially as the project scaled up with numerous modules using Paparazzi tests. The journey from diagnosing to defeating cache issues offers invaluable lessons on maintaining cache integrity without sacrificing functionality.
Batteries -Introduction – Types of Batteries – discharging and charging of battery - characteristics of battery –battery rating- various tests on battery- – Primary battery: silver button cell- Secondary battery :Ni-Cd battery-modern battery: lithium ion battery-maintenance of batteries-choices of batteries for electric vehicle applications.
Fuel Cells: Introduction- importance and classification of fuel cells - description, principle, components, applications of fuel cells: H2-O2 fuel cell, alkaline fuel cell, molten carbonate fuel cell and direct methanol fuel cells.
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
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Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
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the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...
Psv fire training weldfit
1. Fire Case PSV Sizing Common Mistakes
Presenter: Eric Parvin, Parv Consulting
Hosted by: Adam Murray, Weldfit
2. PSV Evaluations
Very brief review of our company:
We do much more than PSVs-but that is one specialty. We are voting members of API 520/521, contributing
editor of GPSA Engineering Data Book 14th ed., former adjunct professor at Colorado School of Mines, and a
PE in many US states and P.Eng. in Alberta, Canada.
We offer training in PSV’s, distillation tray design, and overall fractionation train designs.
Our process engineering expertise ranges from upstream to refineries and chemical plants, and is extensive
in equipment design, troubleshooting and more. See our website for details: www.parvconsulting.com.
We also host a “Process Pop Quiz” on LinkedIn from time to time. See here for past articles and pop quizzes
at: https://www.linkedin.com/in/eric-parvin-p-e-p-eng-b2519b29/
Current Customers:
Syncrude, Suncor, Big West Oil, Consumer Energy, Hellervik Midstream, Encana, Keyera, Halker, Southcross,
Weldfit, and more.
3. Why the Class?
Lots of errors found when performing independent audits of others
• Software Improvements in Industry
• Hysys Dynamics / Safety Analysis Tool
• VMG PSV Sizing
• Many other PSV software now available (iPRSM, PSPPM, others)
I encourage other EPC firms to join our class—drives unity and consistency among
the EPC’s.
Don’t Want “3 Engineers, 4 Opinions”—nobody wins.
Because of this happening with one client, we have developed a PSV guideline on
how to address all scenarios, especially fire sizing.
3
4. PSV’s Don’t Prevent…
Recent event: Port Neches, TX explosion
Fire went on for ~ 12 hour before the tower in the picture below
”took off”. Please remember—PSV’s prevent overpressure, they do
not prevent over-temperature. Normal carbon steel vessels will
typically yield at lower pressures when temperatures exceed 800-
1000F.
Initial explosion:
https://www.youtube.com/watch?v=yosSaBMHLKc
Secondary explosion (the vessel that launches is a distillation
tower)
https://www.youtube.com/watch?v=FBh8ahDa04Y
And
https://www.youtube.com/watch?v=18WZaFGPpoM
The afternoon explosion, people >52 miles away said the walls in
their homes shook.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
4
5. Fire Cases Normally Apply
Can I dismiss fire?
ASME VIII Div. 1 UG-125-UG-140 discusses this in sections…in short
• If no flammables are around—you can:
• Must have appropriate multi-discipline sign-off
• Other requirements listed in ASME code
• If flammables are around, then need to have a PSV sized for fire case—period.
• Seen several upstream clients “dismiss” fire as not needing to size it
• Fabricators for heater treaters or other upstream common vessels provide a nozzle
TOO SMALL for appropriate PSV (NOTE: fabricators are not necessarily responsible
for sizing this…analogous to internal flange gasket).
• If you’re in a code compliant state, ASME must be followed.
• If you’re in a non-code state, but the vessel is ASME stamped, check your state’s
requirements—interpretations may still mandate following ASME for PSV sizing if
it’s built to ASME code even though the state is not a code compliant state.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
5
6. Fire—For Today’s Discussion
Pool Fire (Large Liquid Pool) of Refinery Liquids.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
6
FOR THE HEAT FLUX INTO THE VESSEL
Familiar Equation
Q = C * F * Aws 0.82
C = 21000 or 34500
F = Environmental Factor (e.g. fireproof insulation)
Aws = Wetted Surface Area (ft2)—area inside the vessel where liquid absorbs heat
Most commonly see Q= 21000 * Aws0.82
There’s a lot of assumptions in that 21000 number….
Won’t discuss insulation today
7. Fire—C coefficient
The 21,000 coefficient assumes
• Good Drainage
AND
• Good firefighting techniques.
Right—typical well pad in remote Weld County, CO.
Below—typical refinery.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
7
8. Fire—Wetted Area
Wetted Area factor is dependent on the liquid level assumed inside.
We have followed behind many other larger EPC firms and PSV
specialists that use high liquid level (HLL) or a conservative value,
and report a PSV as being to small.
What level do you use?
• Should be only the area within 25 ft. of “local grade” (solid surface, including elevated
decking with solid flooring)—see 4.4.13.2.2 for details as to why.
• See API 521 4.4.13.2.3—provides the liquid level to use in most vessel applications
• For example, towers, NORMAL liquid level plus height of liquid on all trays above it
• For working storage (reflux drums, feed drums), use maximum liquid level
• Other examples exist in API
• 4.4.13.2.2 states that vessel heads inside skirts can be NEGLECTED from wetted area
(MANY contractors don’t take credit for this)
• Connected piping should be considered—(not detailed today)
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
8
9. Fire—Wetted Area
Q = C * F * Aws 0.82
Rarely noticed is API 521 4.4.13.3…if the fire is in a confined area,
then the heat flux can be higher, and this section of API 521 states
that the 0.82 power should be changed to 1.0.
Potential examples: Inside compressor houses; inside specialty
chemical housing areas; heater treaters inside sheds for
winterization; air compressor buildings (which have flammables in
there too); and anywhere there’s a building, shed, or confining space
for a fire to occur. A vessel against a wall is also to be considered.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
9
10. Fire—Wetted Area
What about when a single PSV protects multiple vessels?
The wetted area of 3 vessels is shown below. Assume the same liquid is in each vessel for
ease of comparison (e.g. latent heat = 200 BTU/lb).
Q= 21,000 * (A1+A2+A3)^0.82 or 21,000*(A1^0.82 + A2^0.82 + A3^0.82) ?
Area 1 = 100 ft2
Area 2 = 200 ft2
Area 3 = 300 ft2
Group 1, total Q = _3.98MMBTU/hr_ or Group 2, total Q = __4.79MMBTU/hr_
Difference of 20%. The correct way is Group 2.
API has commented on this previously, but also remember the equations were derived
empirically using single vessels. Also “simple math” tells you this is true.
Now we have a heat flux—what next?
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
10
11. Fire—Latent Heat
Once you have the wetted area you can find the mass flow rate for the relief scenario through
the PSV by m = Q / λ (instead of λ we will use “LH” from now on)
What is latent heat?
• At normal (below supercritical) conditions, it’s interpreted by most as the energy to vaporize
1 lb. of liquid into vapor.
• From a chemical (single component) perspective, it’s the change in enthalpy between 1 lb of
liquid and 1 lb of vapor formed
• Is determined AT RELIEVING CONDITIONS--Can be at full accumulation pressure
• For fire cases—it’s the energy required to ”liberate” one pound of material from the liquid.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
11
12. Fire—Latent Heat
Where does API discuss latent heat?
API 521 4.4.13.2.5.2
Also:
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
“On occasion, a multicomponent liquid can be heated at a pressure and temperature that
exceed the critical temperature or pressure for one or more of the individual components.
For example, vapors that are physically or chemically bound in solution can be liberated
from the liquid upon heating. This is not a standard latent-heating effect but is more
properly termed degassing or dissolution. Vapor generation is determined by the rate of
change in equilibrium caused by increasing temperature.” (italics added)
For these and other multicomponent mixtures that have a wide boiling range, it might be
necessary to develop a time dependent model where the total heat input to the vessel not
only causes vaporization but also raises the temperature of the remaining liquid, keeping it
at its boiling point.
12
13. Fire—Latent Heat
SENSIBLE HEAT: when boiling a fluid (let’s HD-5 propane) from bubble point to vapor, what’s
the enthalpy equation look like:
Q = m * Cp * dT + m * LH
The first term is the sensible heat portion of heating the liquid while simultaneously boiling
liquid into a vapor (latent heat, LH).
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
13
14. Fire—Latent Heat
Q = m * Cp * dT + m * LH
For multi-component systems that begin to boil, does this term exist?
Sensible heat does “exist” when boiling large boiling point range materials—
in fact it’s quite significant. It makes your LH for boiling off 1 pound of fluid
at relief conditions 10%+ higher.
Call this “Latent Heat with sensible heat effects”
(Hysys graph
Of the 2 curves)
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
14
15. Fire—Latent Heat
For multi-component systems or wide boiling point ranges, where do you evaluate LH?
Some rules of thumb to recall:
• As T increases, PSV area required increases
• As T rises, LH reduces, PSV area required increases more
• As T rises, MW increases, PSV area required decreases slightly
• As T rises, you are boiling off liquids, wetted area decreases, heat input decreases, PSV
area required decreases.
So let’s take a look at the competing variables in a vertical cylindrical
vessel (QUALITATIVELY, not a real example)
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
A=
W TZ / M( )
1
2
CKd
P1
Kb
15
18. Fire—Latent Heat
Working through a pseudo relief case, you can develop an area required graph like this one.
Notice the dip around the 10% mark and then localized peak in area required.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0% 20% 40% 60% 80% 100% 120%
PSV Area Required
Area Required
18
19. Fire—Latent Heat
Have seen similar systems (esp. In horizontal drums that start nearly liquid full) these other
colored curves for area required first-hand in various systems, especially crude oil, gasoline,
diesel, and other wide boiling point range hydrocarbon mixtures.
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0% 20% 40% 60% 80% 100% 120%
PSV Area Required
Area Required
19
20. Fire—Latent Heat
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
Before we look at an example of latent heats, let’s discuss popular methods
to extract latent heat from a simulator:
A) Liquid “Properties” tab
B) Vapor Condensing
C) “100 drums, 100 latent heats”…(not shown)
D) Set up a “case study” with 1 drum—”True Latent Heat” below
20
24. Fire—Latent Heat
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
Gasoline range material (e.g. LSR Naphtha)—case study across all Boiling
Ranges
Anywhere from 15%-21% difference
between Method D and Method A
24
25. Fire—Latent Heat
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
So where have we seen SIGNIFICANT differences in latent heat values when
accounting for sensible heat effects?
• Hydrogen solubility in liquids (hydrotreaters, reformers)
• Seen LHE/SE values in the 2000 BTU/lb range at 10% boiloff point, vs.
150-200 simple simulation LH values.
• Methane solubility in liquids
• Seen values in the 800-2000 BTU/lb range…
• Ethane solubility
• Not as significant as methane, but still increases significantly in
heavier oils (e.g. not in LPG streams)
25
26. Fire—Software Options
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
How do you review this detail yourself? A few options exist…
Hysys has a “Safety Analysis” tool. You can program a PSV.
SO LONG AS YOU DON’T CROSS THE SUPER-CRITICAL RANGE (Hysys defaults
it at z<0.8), you can run a “Semi-Dynamic” analysis.
26
28. Fire—PSV Software Options
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
PSPPM also has a good version of doing the same thing as Hysys.
We have an approach to PSPPM, iPRSM, Hysys, and a few other PSV
software calculation tools to ensure the correct values are used to give the
overall PSV area required on the time dependent analysis.
Salus also has a good tool for doing semi-dynamic analysis similar to Hysys.
VMG can perform a more rigorous fully dynamic analysis to flare systems
and is a good tool as well.
28
29. Fire—Other Factors to Consider
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
Fire—for liquid full vessels
A) In the 1990s it became popular to assume for liquid full vessels, you must assume 2 phase
relief through the PSV
B) Research later concluded that this is not necessarily needed so long as the PSV inlet line is
at “a high point” from the source of vapor generation.
If the PSV is installed at a low point in the vessel (e.g. on the bottom piping of a heat
exchanger), then you “should” design the PSV to relieve the same volumetric expansion of
vapor generation but as liquid expulsion. (Notice it says “should”, not “shall”)
See API 521 Section 4.4.13.2.5.3 for details (3rd paragraph).
Examples:
• Liquid filled filters with PSV coming off side of filter
• PSVs protecting heat exchangers with PSV off bottom of exchanger piping (seen it)
29
30. Fire Case Heat Flux Checklist
Is this a pool fire case? – If no, other methods are necessary.
All calculations are assumed to be blocked in vessel fires
Q=21,000 x F x A0.82
Prompt and effective firefighting and firefighting equipment are available to the area (if not, change 21,000 to
34,500)
Good drainage in the area. (if no, change 21,000 to 34,500)
If taking credit for insulation
Has it been field verified as installed properly and materials of construction of jacketing and banding verified
to withstand fire temperatures?
Has the fill material & thickness of insulation under the jacketing been verified?
Wetted area
Correct liquid levels used, and elevation (25 ft. rule) applied properly?
Skirt on vessel? (If yes, was area of skirt excluded?)
Is it a confined fire? (if yes, change the 0.82 value to 1)
Determine if any other exceptions to wetted area are applicable to the situation at hand.
For protection of multiple vessels, fire variables calculated for each vessel independently
Verify how the level transmitter is calibrated and spanned vs. PI data.
Confirm the types of heads and presence of water boots
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
30
32. Thank you!
Copyright: Parv Consulting
(Eric Parvin / Melissa Parvin) 2016
Thank you for your interest in the class and coming today.
If we can be of any service to you on PSVs, distillation, exchanger or
vessel design, or any operating issues you may have, please contact us.
Special thanks to:
Adam Murray, Weldfit