Wilson boiler blowdown systems are built around the Wilson centrifugal blowdown separator. The boiler blowoff is piped
tangentially into the separator. In the resulting vortex the pressure is released, allowing the steam flash to rise through the vent
while the water and sludge fall through the drain. A stainless steel wear plate protects against erosion in the blowoff entry area.
No water is retained in the separator.
Wilson separators are sized according to boiler operating pressure and blowoff valve size. These are the only two factors
that determine the rate of flow to the separator. Vents are sized to keep internal flash pressures to a maximum of 5 psig
as recommended by the National Board of boiler and pressure vessel inspectors and as required by some state and municipal
code authorities. Sizing information for standard models is tabulated on the following pages.
ASME design pressure of the separator should equal a minimum of 25% of the boiler maximum allowable working pressures
(mawp) as recommended by the National Board. Design pressure for each standard model is shown on the following pages.
Most codes covering this type of equipment includes a maximum temperature limitation on wastes entering public sewers.
Anti-pollution laws, which are widespread and universal, also include temperature limits for discharge to sewers and public
waters. The Wilson aftercooler, properly sized for conditions, efficiently takes care of this problem.
Wilson equipment designed for hot water relief valve service is widely used for most economical and efficient disposal
of relief valve discharge.
• Local boiler and plumbing codes vary and should be checked.
• Select a separator model by boiler blowoff valve size, boiler operating pressure and local codes.
• The inlet connection on the separator must match the boiler blowoff valve size. One separator can be used in a battery of boilers. In this case, the header piping should remain the same size as the largest blowoff valve in the battery. It should not be increased
• For required cooling of blowdown discharge before entering public sewers
• Type of connections desired: threaded, beveled for welding, or flanged.
Auxiliary equipment available:
• Cooling water control package
• Mounting brackets and supports
Vents sized for maximum of 5 psig in separator. The drains sized for flow of blowdown effluent plus aftercooler water for maximum temperature 140F to sewer. For sizing details refer to Wilson separator selection charts A&B. Note: Custom sizes are available. Consult the factory for more information.
1) Vessel connections may be threaded, flanged, or welded or any combination required by your application. Consult factory.
2) Material thickness must comply with state and local regulations. All separators shown are constructed to A.S.M.E. Code.
3) Separator design pressures are suitable with boiler maximum allowable working pressures to four times the separator design pressure (Per National Board recommendations). Ex:A separator with a 150 psig design pressure may be used with a 600psig
maximum allowable working pressure boiler.
4) Separators may be registered with the National Board (optional).
Aftercooler For Hot Liquids
Aftercooler configured to match separator drain size
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or call: Phone: 712-243-5300