Taylor-Wharton VJ Bulk Tank - Manual (Page 5)

INTRODUCTION
This manual provides information for the user to operate and maintain Taylor-Wharton Cryogenics VJ-
Series Carbon Dioxide Storage Vessels. These tanks are primarily intended for liquid withdrawal at a
normal operating pressure between 260 psig (18 bar/1793 kPa) and 320 psig (22 bar/2206 kPa), the
maximum allowable working pressure is 350 psig (24 bar/2413 kPa). If your application requires the
withdrawal of gaseous product, the flow rate must not exceed the ability of the tank to maintain a
minimum pressure of 200 psig (14 bar/1379 kPa) at all times. The constant withdrawal of gaseous
product at high flow rates will cause a decrease in tank pressure. This effect can be overcome by
installing an electric pressure building vaporizer. Supply and return connections are provided on the
tank to allow for the addition of this feature if required.
CAUTION: To avoid irreparable damage to the structure of the tank, an internal pressure of
no less than 200 PSIG (14 bar/1379 kPa) must be maintained at all times.
These instructions are for experienced operators only. If you are not fully familiar with the principles of
operations and safe practices for cryogenic equipment and supply systems, we urge you to read and fully
understand the SAFETY PRECAUTIONS and REFERENCE PUBLICATIONS listed in this manual.
Tank specifications, flow diagram and an elevation with bottom view of the tank showing controls
and piping may be found on the General Arrangement Drawings located in the back of this manual.
Additional copies of these drawings may be obtained from the factory. Please include information on
the tank model number and part number in making drawing requests. Tank Specifications, Rigging
Details and Vacuum System Components are also shown in this manual.
PROPERTIES OF CARBON DIOXIDE
Under normal atmospheric conditions, Carbon Dioxide exists as a colorless, odorless gas, which is about
1.5 times heavier than air.
When confined to a storage tank, depending upon the pressure carbon dioxide can exist in any three
states of matter; SOLID, LIQUID and GAS. The point at which all three states may exist is 75 psia
[60.4 psig (4 bar)]. This is the triple point. At temperatures and pressure below these values, carbon
dioxide may either be a solid or a gas, depending on the conditions.
At temperatures and pressures above the triple point, carbon dioxide liquid with overlaying gas may exist
in equilibrium within a closed vessel.
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