Process system explosions

The Chemical Process Industry (CPI) uses various quantitative and qualitative techniques to assess the reliability and risk of process equipment, process systems, and chemical manufacturing operations. These techniques identify the interactions of equipment, systems, and persons that have potentially undesirable consequences. In the case of reliability analyses, the undesirable consequences (e.g., plant shutdown, excessive downtime, or production of off-specification product) are those incidents which reduce system profitability through loss of production and increased maintenance costs. In the case of risk analyses, the primary concerns are human injuries, environmental impacts, and system damage caused by occurrence of fires, explosions, toxic material releases, and related hazards. Quantification of risk in terms of the severity of the consequences and the likelihood of occurrence provides the manager of the system with an important decisionmaking tool. By using the results of a quantitative risk analysis, we are better able to answer such questions as, Which of several candidate systems poses the least risk Are risk reduction modifications necessary and What modifications would be most effective in reducing risk ... 

Illustrate the layered accident investigation process, using Example 13-1 as a guide, to develop the underlying causes of the duct system explosion described in section 13-1. 13-2. Repeat Problem 13-1 for the bottle of isopropyl ether accident described in section 13-2. 13-3. Repeat Problem 13-1 for the nitrobenzene sulfonic acid decomposition accident described in section 13-2. 

Explosion phenomena have occurred in all types of confined and unconfined units reactors, separation and storage units, filter systems, pipe lines, and so forth. Typical reactions that may cause explosions are oxidations, decompositions, nitrations, and polymerizations. Examples of chemical and processing system characteristics that increase the potential for an explosion are the following ... 

Detonations produce much higher pressures than what be considered ordinary explosions. In most cases a process vessel or piping systems will be unable to contain detonation pressure. The only safe procedure is to avoid process system detonations is to preventing the formation of flammable vapor and air mixtures within vessels and piping systems. While the flame speed of explosions is at relatively slow speed, detonations travel at supersonic speeds and will be more destructive. 

Release of combustible chemical vapors to atmosphere during process upset. Explosion impacted capability of the fire suppression system. 

As for Allende s inclusions, variable contributions of a component produced in neutron-rich nuclear statistical equilibrium best explains the Ti- Ca data. Some parts of the solar nebula were depleted in these isotopes as deficits are also seen. There are several possibilities for explaining the variations in Ti. 1) The neutron-rich component itself may be heterogeneous and incorporate locally less neutron-rich statistical equilibrium products (Hartmann et al. 1985). 2) Ti may result from another process like explosive Si or He burning (Clayton 1988). This component would be associated with the neutron-rich component but not completely homogenized. In all cases, carriers are solid grains which may have behaved differently than the gaseous nebula during the formation of the solar system. A minimum number of components may be calculated to account for the Ca and Ti isotopic data, which number up to 3 (Ireland 1990) but to be conservative at the 5ct level, clearly resolved effects are present only on 3 isotopes ( Ca, Ti, Ti). 

Much of process safety deals with the prevention of catastrophic events, such as fires and explosions. This is accomplished by containing hazardous materials within the process system. The Center for Chemical Process Safety (CCPS) has developed many Guidelines that assist companies in this effort (see Section 1.3 and References). 

The mine-handling system is the last demilitarization processing system. Operators unpack mines from their drum containers in the unpack area. Each mine is then cycled through a glove box onto a conveyer in the explosion-contaiiunent vestibule. This conveyer takes them to a workstation where the arming plugs, fuses, and activators are removed and placed in a fuse box. The fuse box and the mine are then transported to the explosion-containment room, where a mine machine punches the mine and drains the agent, A burster punch... 

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