Process vessels storage potential

Because process heating is expensive, lagging is invariably applied to heated process vessels to minimise heat loss, particularly during long-term hot storage. Such adiabatic or near-adiabatic systems are potentially hazardous if materials of limited thermal stability, or which possess self-heating capability, are used in them. Insufficiently stabilised bulk-stored monomers come into the latter category. 

Confined Space any space not intended for continuous human occupancy and having a limited means of egress. A permit-required confined space contains or has the potential for a hazardous atmosphere (toxic, flammable, or oxygen deficient) and/or engulfinent or entrapment hazards. Confined or enclosed spaces include, but are not limited to, storage tanks, process vessels, bins, boilers, ventilation or exhaust ducts, sewers, underground utility vaults, tunnels, pipelines, and open top spaces more than 4 feet in depth such as pits, tubs, vaults, and vessels. 

Describe the process of creating a vacuum in a storage vessel as a result of condensation. Develop an example to illustrate the potential magnitude of the vacuum. 

Storage vessels are usually located on tank farms. The space around a tank and the distances to other equipment depend on the materials stored, their potential hazardousness and the possibility of the unexpected changes in storage conditions. Fluid storages should be in a safe location away from process and public areas. It is also important to prevent fire spreading between tanks by keeping the level of heat radiation in an acceptable level (Mecklenburgh, 1985). 

The greatest safety hazard in chemical engineering operations is without question caused by uncontrolled chemical reactions, either within the chemical reactor or when flammable chemicals escape from storage vessels or pipes. Many undergraduate students are never exposed to the extremely nonlinear and potentially hazardous characteristics of exothermic free radical processes. 

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