Inżynieria Ekologiczna Nr 2

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IN¯YNIERIA EKOLOGICZNA NR 2
to process refinery gases. The Wap-Flaro system reduces- and in some cases, eliminates
the need for burn off of refinery gases.
The burning of ‘flare gas’ is expensive and damaging to the environment. The concentration
of high temperature burning produces a pollution plume down wind of the refinery
flare stacks plus the fact that it is wasteful to burn off valuable refinery gases. Typically, if
operating a 50,000 bbl per day oil refinery, then ‘so called’ refinery gases, (as listed be-
low) would be burned through the flare stack.
Hydrogen 0.1%,
Methane 1.3%,
Ethane 1.9%,
Ethylene 0.6%,
Plus hydrogen sulphate, (H 2 S) pentane etc.
Consider that approximately 16.5% by weight of the total feedstock is produced as
refinery gases during the refining process. Assume that the specific gravity of the oil is
0.9%. 1 bbl would weigh 189 kgs. So we have 189 multiplied by 50,000 multiplied by
0.9 equals 8,505,000 kgs total of product and refinery gas output would be 16.5% of
this, so: 8,505,000 kgs multiplied by 16.5% equals 1,403,325 kgs per day. If this remains
unrecovered, i.e. burned off in the flare stack, it represents a total loss and remains an
environmental problem.
Let us assume that due to poor heat conductivity, the maximum recovery rate of refinery
gases would be 80% leaving 20% only for processing. At this level we now have 1,403,325
divided by 0.8 multiplied by 0.2 which equals 350,831 kgs per day. Present value = 0.105
USD/kg, so we have 350,831 multiplied by 0.105 which equals $36,837 US per day in
value of recoverable refinery gas.
The Wap-Flaro Process
The principal is very simple. It uses waste heat as the energy source to condense the
gases into liquid form. Wap-Flaro system is a refinery petroleum gas recovery apparatus
driven by normally wasted heat, comprising primarily the cooling system, the heat exchanging
petroleum gas recovery system and the appropriate peripheral equipment so that the
wasted heat from the refining process is used as a power source for creating a vacuum
cooling function to cool the water being heat exchanged with the petroleum gas down to a
temperature of 12–13 °C. The heat in the gas is removed and the gas is condensed into
liquid for reuse. The petroleum gases, ethane, propane etc. which are ordinarily burned in
the torch tower are then recovered for reuse.
As indicated, not only will the Wap-Flaro system reduce the environmental problems on
refineries, but will dramatically increase the efficiency and profitability showing potential increased
profits in the order of $36,800.00 per day, an excellent benefit for refinery operators
to consider, especially since it far outweighs the installation and running costs of Wap-Flaro.
OPEC Ltd. Wielka Brytania
Tel. kontaktowy do Przedstawicielstwa
w Warszawie: (0-22) 647 39 45, 647 06 84
Propylene 2.7%,
Propane 2.3%,
Butylene 4.0%,
n. Butane 2.7%.