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Separates the bulk liquids present within the inlet stream.
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Gradually reduces the momentum of the inlet stream. thus minimising the potential of droplet shatter.
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Reduces re-entrainment of liquid from the liquid surface.
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Reduces turbulence and / or re-circulation in the liquid section.
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Provides a minimal pressure drop.
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Wave Mitigation / Sloshing Effects.
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Reduces the size of the inlet nozzle on a new build project. Hence it permits the design of smaller and lighter separators.
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Allows a greater fluid throughput for a set nozzle size, in a revamps.
Care must be taken to correctly design and size the upstream piping, inlet nozzle and of course the inlet device of a separator as these are all of paramount importance for the correct operation of the “total” separator.
Literally hundreds of separators worldwide suffer unnecessary problems with regards to separation performance, due to undersized upstream piping (often sized based on the choice / size of inlet device/nozzle) or the incorrect choice of inlet device or inlet devices that are operating well beyond their respective design points.
There are many different types of inlet devices available on the market for insertion into separator vessels, each having its own operational parameters, attributes and efficiency; historically the most common types have been “deflector plates”, “simple baffle type”, “inverted dished heads”, “pall ring boxes” and “half open pipes” amongst many others. Today though, more Contractors and Operators are moving away from these types of inlet devices towards the more advanced designs, as they understand the importance of a correctly designed inlet device and the functions undertaken by the different types.
Inlet devices are installed in both horizontal and vertical separators to:
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Minimise the size of the upstream piping and inlet nozzle.
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Minimise Droplet Shatter.
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Reduce the feed stream’s momentum.
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Separate “bulk” liquids.
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De-foam the incoming fluid.
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Ensure good gas and liquid distribution onto the downstream equipment.
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Prevent re-entrainment of liquid from the gas / liquid interface.
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Prevent mixing at the liquid / liquid interface.
Applying a momentum criteria “pv²”, to size the inlet nozzle and inlet device, commonly overcomes the problem of under sizing, i.e. the momentum of the incoming feed shall not exceed a “prescribed level” for an inlet nozzle designed with a generic type of inlet device (erosional velocities are also reviewed).
This method is a very common design parameter used by many operators, contractors and “process houses” in determining the correct size of the inlet nozzle. Dependant on the application, the higher the pv², then the smaller the inlet nozzle and in many cases the upstream piping, thus, a correctly designed inlet device can lead to a reduction in Capital Expenditure (CAPEX) as well as increasing the performance of the separator.
