Pressure vessels drum size

Reducing vessel size depends on the gas-oil ratio and the pressure level of gas compression. Two smaller vertical vessels—one servicing a high-pres- sure relief header and one servicing g a low-pressure relief header—will oc- 4 cupy less space than one large low-pressure relief drum., ... 

Dresden-I showed that it was possible to operate with a steam quality high enough that external risers and an external steam drum were no longer necessary. Modern BWRs incorporate steam separators and driers mounted above the core inside the pressure vessel itself. A further advance is the adoption of internal jet pumps, mounted on the inside of the pressure vessel, for circulation of the coolant through the core. These are driven by external loop pumps, but the fraction of the core recirculation flow which is required to drive the jet pumps is only about one third of the whole, leading to a reduction in the number and size of the external loops, with a consequent reduction in the severity of the potential effects of breaches of the primary circuit. 

Closed drain headers are normally provided for safe drainage of equipment containing severely toxic, corrosive, pollutant or high cost chemicals (e.g., phenol, sulfuric acid, monoethanolamine, sulfur dioxide, catacarb) where there is an appreciable inventory in a number of processing vessels in a plant. The header should be at least 50 mm in diameter, and should be tied into the major vessels and equipment with 25 mm minimum size connections (20 mm is considered adequate for pumps). The header may be routed to a gravity drain drum (with recovery to the process by pump or gas pressurization), or to a pumpout pump returning to the process, or in the case of sulfuric acid, to an acid blowdown drum. 

In some cases, it is possible to combine the functions of blowdown and disengaging drums in one vessel. However, PR devices discharging liquid hydrocarbons lighter than pentane should not be connected into the drum if there is a possibility that such liquids could accumulate and be released to the sewer through the seal leg. Also, the drum vent should be sized to prevent pressure buildup due to vaporization. In these applications, the design criteria for both services must be met and special attention should be paid to potential hazards and problems which may be introduced, such as ... 

Process flowsheets embody the material and energy balances and include the sizes of major equipment of the plant. They include all vessels, such as reactors, separators, and drums special processing equipment heat exchangers pumps and so on. Numerical data include flow quantities, compositions, pressures, and temperatures. Major instrumentation essential for process control and the complete understanding of the flowsheet without reference to other... 

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