Page 88 - Impiantistica industriale

OIL INDUSTRY

Figure 4 – 3D Model View of the new Closed Blowdown System

liquid to the Fractionator Column for reprocessing.
One portion of the condensed oil is recirculated Steam, entrained hydrocarbons, and non-con-
back to the Blowdown Tower as reflux under flow densable vapors flow from the Blowdown Tower
control through the Blowdown Circulating Oil Cooler overhead to the Blowdown Condenser, where the
while another portion is heated in the Blowdown steam and entrained hydrocarbons are partially
Tower Heater and routed back to the Blowdown condensed.
Tower below the bottom shed tray. In both cases, The vapor-liquid mixture flows to the Blowdown
the Blowdown Circulating Oil is routed to the Settling Drum, where the oil is separated from the
Blowdown Tower using the Blowdown Circulating water. The Blowdown Slop Oil Pump transfers
Oil Pump, which is expected to run continuously. the oil in the Blowdown Settling Drum back to the
The API density of the Blowdown Circulating Oil Blowdown Tower or alternately to the Slop Tanks.
is analyzed daily. If the density of this stream is The Blowdown Sour Water Pump transfers the
considered higher than the expected normal value, sour water from the Blowdown Settling Drum
the LCGO make-up is fed to the Blowdown Tower under level control to Sour Water Tank.
to dilute the bottom stream of the column. Hydrocarbon vapors from the Blowdown Settling
The primary use of the circulating oil from the Drum are eventually sent to the Flare.
Blowdown Tower is to quench the vapors entering
the tower. This stream flows through the Blowdown
Circulating Oil Cooler, which is also used as reflux to Project Execution Plan
recover/condense the oil and wash coke particles
from the incoming vapor stream. The temperature Wood has worked alongside
of the Blowdown Circulating Oil Cooler discharge is
controlled by the use of 100% variable speed fans. OMV Petrom S.A. in the
The second portion of the blowdown circulating oil “Petrobrazi refinery for more
is used to heat the Blowdown Tower bottoms pool than ten years, especially
when the blowdown system is idle. The circulating
oil from the Blowdown Circulating Oil Pump is leveraging the experience of the
heated to a prescribed set point in the Blowdown Delayed Coker Technology
Tower Heater using Medium Pressure Steam and
then routed to the Blowdown Tower above the
liquid pool. The Blowdown Tower level is controlled OMV Petrom S.A. awarded Wood a contract
with a primary flow control valve to the Coke Drum to deliver the Engineering services of the early
overhead quench and a secondary valve in case the Select and Define phases executed in 2016 and
level increases to the high liquid level, to route the 2017. The objective of these early phases was to

86 86 Impiantistica Italiana - Maggio-Giugno 2019