Cu possibility of some thing going wrong is

Cu by mially upetators when working
with but to always respect it’ y operators when working w h TEA is never to
fear is 2) Process description. See P Diagrams and attached sketch The
TEA, or tri-ethyl aluminum is supplied from America or Europe in a 20 M3 Witco
No 9 container mounted in steel ISO frame to facilitate intermodal transport by
sea and road. When the “Witco container arrives at the plant, it is moved
and stored in the container area. When required by the process, the container
is weighed to ensure it contains the correct amount of TEA and then moved to
the TEA loading bay. When it is safe to do so, the container is connected and
transferred into the TEA system. This is the most dangerous part of the TEA
system and many things can go wrong. It is important to be careful, mindful and
alert when completing this procedure. From the Witco container, TEA is
transferred into the V 2300 buffer tank. The tank has a holding capacity of
0.54 m3 and should last 24 hours. After a transfer the system must always be
flushed with white oil. If there is no TEA left in the lines then the
possibility of some thing going wrong is reduced. The white oil is supplied via
a pneumatic barrel pump. The same system is used to flush the pumps. Never
assume that the lines is flushed, always flush them before any breaking of TEA
lines is done. The tank is under a constant nitrogen blanket and pressurized to
ensure the integrity of the blanketing. The positive pressure in the tank and
TEA system prevents Oxygen and other contaminants to enter the system as TEA
reacts violently and spontaneously with oxygen and explodes when it comes into
contact with water The V 2300 pressure is been controlled by a “Split
range controller, (the same as V 2200). The high pressure will be let down to a
safe area (fire pit but first go through the TEA vent pot (V 2301), which is
filled with white oil. The white oil absorbs the TEA residue. The TEA present
in the oil should be monitored on a weekly basis. Half of the oil should be
drained when necessary. (fig.6 TEA system +wetco
container pic)

6-Reactor System.

 Purpose of The homopolymer reactors or reactor
systems is the heart of the PP plant. Its primary function is to convert raw
materials as propylene, hydrogen and catalyst into polypropylene powder. The
reactor system is a closed loop system, primarily utilizing fresh feeds such as
hydrogen and propylene and converting these chemicals into raw PP. By
circulating or ‘recycling’ these chemicals, the system optimizes the feedstock’s
to consume the maximum amount of fresh feeds in the conversion process The
reactors fresh feeds arrive from a large variety of sources, each of which will
be briefly discussed in this module. However, for a detailed description of
those fresh feed systems, refer to their own individual modules.

Propylene
is converted to polypropylene using a ZIEGLER type catalyst at a pressure of
30-32 bar G and a temperature of 75-85 °C. The catalyst system comprises a
solid catalyst (PTK4 W) and the liquid co-catalyst of Tri ethyl aluminum (TEA).
The co-catalyst is an indispensable part of the catalyst system. The molecular
mass of the polymer (chain length) is controlled by the addition of Hydrogen
and is measured by the Melt Flow Index (MFI) of the polymer, The stereo-regularity
or tacticity of the polymer chains is controlled by the addition of a
stereo-modifier, Silane, (an alkoxi ca compound sold under the name of CHMS or
“C Donor”) to the polymerization reactor. Stereo-regularity is
measured by the Xylenes Soluble” of the polymer The MFI and the Xylenes
solubles are the parameters which must be controlled in the polymerization
reactors. For more 

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