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Safe storage, handling, and transportation of reactive chemicals is challenging. Characterization of both desired and undesired chemistries requires a variety of methods including theoretical and computational screening, testing, and detailed modeling. A multitude of process and environmental conditions

Safe storage, handling, and transportation of reactive chemicals is challenging. Characterization of both desired and undesired chemistries requires a variety of methods including theoretical and computational screening, testing, and detailed modeling.

Fatigue failure of relief and/or process piping caused by vibration can develop due to the conversion of flow mechanical energy to noise. Factors that have led to an increasing incidence of noise vibration related fatigue failures in piping systems include but are not limited to

A classic scenario in risk assessments is the exposure of process/storage vessels and piping to an external pool fire or a jet fire. The heat from a fire causes the temperature of the metal walls to increase and subsequent heat transfer from the metal walls causes the pressure and temperature of the vessel and piping contents to increase.

Direct scale-up methods have been used to develop relief requirements and vent sizing for runaway reactions since the early 1990s. Direct scale-up methods have been popular because one is able to measure in a laboratory test the required relief size in equivalent vent area per unit mass of a reacting mixture, in 2/kg, and then scale it up to plant scale equipment sizes.

Reliable flow estimates are essential for the sizing and selection of process equipment including but not limited to relief devices, process piping, and depressuring systems. In addition, reliable flow estimates from loss of containment scenarios can significantly influence the quality of consequence, risk analysis, and facility siting studies as well.

A common scenario that is encountered in pressure relief systems design centers around the calculation of vapor generation rates from liquids under external heating, internal heating, or fire exposure. Pressure relief design is all about a volume balance. As the heating increases the liquid temperature and generates more vapor (volume) in a vessel, the pressure increases to fit the additional vapor generation (volume created) within the confines of the vessel.

High viscosity two-phase flow occurs in many industrial scale reactors handling polymer systems. For example, a runaway reaction in a monomer tank can lead to high viscosity two phase flow.

Flame arresters are used in chemical processing facilities to prevent flames from burning into process vessels during either emergency relief or normal operations. Flame arresters work by forcing the flame through one or more narrow passages that are long enough to decelerate the flow and increase the residence time for heat transfer and that are small enough to increase heat loss from the flame surface to prevent the flame from propagating.

Due to the design vintage of many petroleum refineries and petrochemical plants, existing pressure relief and flare systems may be overloaded because of prior unit expansions / upgrades have increased the load on the flare for combined flaring scenarios beyond the original design intentions.

Large equipment items, such as distillation column systems, compressors, or major pressure vessels, are commonly protected by multiple pressure relief devices mounted on a common inlet manifold. In selecting this type of design, the potential exists to inadvertently overlook the flow characteristics associated with such a common inlet manifold.

This paper examines an overpressure relief protection for pipeline, specifically designed for hydrogen peroxide transport over an extended distance. Presented as a case study, it includes a series of sensitivity analyses, accounting for all credible overpressure scenarios, to obtain an optimal placement of relief devices along the pipeline.

The purpose of this article is to present a basic understanding of flames, flame arresters, and the multitudinous designs of flame arresters to help an Emergency Relief System (ERS) designer in selecting an appropriate flame arrester. The need to understand the characteristics of the flammable system and appropriate testing is presented. Various prominent manufacturers of flame arresters are presented and a recommendation to select the final product is also presented.

In a 2001 comprehensive investigation report on reactive chemicals, the United States Chemical Safety and Hazard Investigation Board (CSB) reported that 22% of reactive chemicals incidents occurred in storage equipment and 25% occurred in reactors. 167 incidents were considered between 1980 and 2001. Although not specific to polymer systems, the storage equipment category includes monomer storage tanks and the reactors category includes polymerization reactors. Free-radical polymerization reactions are the best studied reactions in all of chemistry.

The API and ASME guidelines and standards for emergency relief systems both state that total nonrecoverable inlet pressure losses between protected equipment and a spring-loaded relief valve should be limited to 3% of the relief valve set pressure.