Taylor-Wharton EF-1500 - Manual (Page 13)

BT-481 REV. B
13
Internal Vaporizer, External Vaporizer Inlet, and Economizer Circuit
The Internal Vaporizer circuit vaporizes cryogenic liquid and warms it to ambient temperature for use in the final
application. Opening the gas use valve (V-11) allows liquid, driven by the pressure within the vessel, to flow through the
vaporizer. The vaporizer uses heat from the ambient air to convert the liquid into a gas and warm it. The vaporizer is
attached to the inside surface of the vacuum jacket. .
The vaporizer inlet circuit provides pressurized cryogenic liquid to an external vaporizer. An external vaporizer is not
supplied with the Express Fill 1,500. Opening the gas withdrawal valve (V-4) allows liquid, driven by the pressure
within the vessel, to flow into the external vaporizer. The vaporizer uses heat from the ambient air to convert the liquid
into a gas and warm it.
The economizer circuit reduces product loss due to normal evaporation of the liquid within the vessel. The pressure
builder outlet valve (V-6) and the economizer circuit isolation valve (V-5) must be open for the circuit to function. The
economizer regulator (PCV-2) opens when the pressure within the vessel exceeds the economizer setpoint. This allows
gas from the top of the vessel to flow into the vaporizer circuit. Provided that gas from the vaporizer is being withdrawn
for use, the vessel pressure will be reduced. The primary safety valve (SV-1) will be prevented from opening, avoiding
product loss.
The economizer circuit may be isolated for maintenance without emptying or depressurizing the vessel. Closing the
pressure builder outlet valve (V-6) and the economizer circuit isolation valve (V-5) isolates the circuit. Two relief valves
(SV-2 and SV-3) prevent the circuit from over pressurizing in the event that the valves are closed while the circuit
contains cold gas or liquid.
Figure 5: Internal Vaporizer, External Vaporizer inlet, and economizer circuit highlighted in red.
CN-4
SV-3
PCV-2
V-6
SV-2
V-5
V-4
V-11
CN-7