LNG Risk Management

Managing the risks of onshore and offshore LNG facilities via a thorough understanding of the design and key issues associated with liquefied natural gas.

Our multifaceted approach takes into consideration the needs of regulators, engineering contractors and most importantly, you. LNG terminals, send-out facilities and associated pipelines, and power plants around the world rely on our extensive experience to complete QRAs, HAZOP and hazard identification studies, safety integrity level (SIL) reviews, and consequence analysis modeling.

Learn More

Have a Question on LNG Risk Management?

Contact Us

Our Team

Georges A. Melhem, Ph.D., FAIChE

President & CEO The founder of ioMosaic and internationally renowned expert in the areas of pressure relief and flare systems design, chemical reaction systems, process safety and risk analysis. Read more...

Neil Prophet

Senior Vice President and Partner He brings over 20 years of experience in pressure relief and flare systems design project management and engineering expertise for chemical, pharmaceutical and petrochemical companies. Read more...

John Barker, Ph.D.

Director The head of our international offices in the U.K. and the Kingdom of Bahrain and an expert in risk management for oil, gas and transportation. Read more...

Marcel Amorós Martí

Director and Partner His expertise consists of a diverse range of industries from chemical and petrochemical to oil and gas and utilities. Read more...

Charles Lea, P.E.

Director, Minneapolis Office Lead He directs a number of large technical projects across multiple offices and is also responsible for all project management in our Minneapolis office. Read more...

Featured Resources

 

Quantify Non-Equilibrium Flow and Rapid Phase Transitions (RPT)

Although non-equilibrium flow and rapid phase transitions (RPT) are well researched, the literature published so far does not explicitly quantify the RPT phenomenon or provide reliable methods for the calculation of non-equilibrium flow for mixtures. Download this paper for a clear understanding of how non-equilibrium flow and rapid phase transitions develop and how they should be quantified for pure components and mixtures alike.

Read the White Paper

Mechanical Integrity Considerations in LNG Depressurization

In a typical LNG installation, a rapid depressurization can cause cryogenic temperatures in both upstream and downstream connected process equipment and piping. This phenomenon, sometimes referred to as auto-refrigeration, can compromise the equipment’s mechanical integrity and pose a risk of material embrittlement. As vessel metal walls are exposed to temperatures below the minimum design metal temperature (MDMT), permanent damage is possible. The potential for brittle failure is even more pronounced for a non-fire scenario. The level of severity depends on the initial pressure, initial temperature, content inventory, depressurizing rate, fluid composition, surrounding conditions, and heat transfer mechanisms.

Emergency depressurizing valves must therefore be sized to ensure a reasonable compromise between the impact of pressure and temperature. This paper examines the effects of different liquid levels, depressurizing valve sizes, vessel wall thicknesses, thermal insulations, and fluid compositions. The primary objective is to identify and illustrate the key factors that influence the mechanical integrity of a typical LNG installation, particularly at the mid to lower end of methane fluid compositions, and their impacts on carbon steel.

Introduction

Emergency depressurizing systems (EDPs) are designed to reduce pressure by expelling the fluids and/or inventory from the protected equipment, thereby reducing the risk of equipment failure. Typical scenarios considered for emergency depressurization are external fire, uncontrolled reactions, and process vessel leaks.

Figure 3: Wall Segment Temperature Profile

Figure 3: Wall Segment Temperature Profile (50% Initial Liquid Level, 2" EDPV).

In the event of a pool fire or jet flame impingement, not only do the system contents experience a rise in temperature and pressure, but the temperature of the system’s walls rises as well. As the temperature of the metal increases, its mechanical strength decreases. Since the portion of the vessel filled with liquid predictably absorbs most of the heat, the main area of concern would be the unwetted or dry wall exposed to fire. As heating continues, the tensile strength is further reduced. Eventually, the wall metal temperature will reach the vessel’s ultimate tensile strength, causing equipment failure.

Much literature has been devoted to addressing system depressurization for fire scenarios; this paper focuses on the scenario of a vessel leak, alternatively referred to as a non-fired or cold depressurization. Due to expansion cooling and condensation of light ends, rapid depressurization can cause cryogenic temperatures in both upstream and downstream connected process equipment and piping.


Featured Case Studies

Process Safety Management Quality Audits

Companies have implemented their process safety management programs to comply with OSHA and EPA requirements, but they continue to have accidents. Process safety management programs can meet the letter of the law, but may not be effective in preventing accidents. Traditional audit programs look at documentation and procedures, but do little to evaluate the program quality or effectiveness.

View Case Study
An LNG plant in the U.S. was planning the renovation and expansion of its existing facilities, as well as replacing and installing new pipelines for transmission and distribution. Before construction began, the client needed to be sure the potential risks were identified and successfully managed to prevent any release of LNG and damage to their existing equipment and storage tank. 
Read more...
An LNG manufacturer had four nearly identical trains with three flare header systems. The client decided they wanted to use a new and more stringent criteria than previously performed under a different design criterion. The large scope and tedious nature of the data entry was a challenge since all calculations needed to be checked to determine the maximum pressure each flare pipe line would be exposed to.
Read more...

The California Energy Commission was directed to assist in the development of clean alternate transportation fuels. As part of this effort, they support the commercialization of fuel cell vehicles operating on hydrogen fuel. In order to be used extensively in the transportation sector, the safety of hydrogen production, storage, and supply needed to be addressed.

Read more...

Featured Videos

Latest News

Want to Get the Latest News from ioMosaic?

Sign Up Now