Page 15 - Industrial Plants 2014

pH control was achieved in a wastewater stripping
column minimizing the usage of steam for stripping
operation. Herein a brief description of plant and
process will be provided, highlighting operation and
control challenges, followed by a brief description of
project goals and technologies implemented to deal
with the problems. Conclusions will show some
results and achievements in term of process
manageability and energy efficiency improvements.

Integrated Gasifcation Combined

Cycle (IGCC)

IGCC plants are among the most advanced and
effective plants for power generation from refinery
residuals, such as vacuum residue, heavy oil,
petroleum coke and coal. The fossil
fuel is converted by a partial oxidation IGCC plants are among
process to produce synthesis gas the most advanced
(syngas), rich in CO and H ; the
2 and effective plants for
syngas is then burned to generate power generation from
electricity by combined cycle. refnery residuals, such
The plant converts about 120 tons/h as vacuum residue,
of heavy residual oil, provided by the heavy oil, petroleum
nearby refinery, into more than 500 coke and coal
MW of electric power and can be
divided in three main areas (figure 1):
• Solvent Deasphalting Unit (SDA) treats the
heavy residues from the refinery: the
deasphalted oil (DAO) is sent back to the
refinery, while the asphalt is fed to the
Gasification Unit;
• gasification transforms the asphalt into syngas;
ocal environmental regulations this section includes different units,
impose to industrial plant operators encompassing units for sulphur, carbon, acid
to treat process wastewater in order gas and heavy metal recovery, which are
to comply with discharge limits. Most removed prior the combustion;
of the industrial plants and utilities • Combined Cycle Unit (CCU) includes two trains
L have process units devoted to for power generation, each of them with a gas
wastewater where those are treated by mean of turbine, a HRSG and a steam turbine. Fig. 1 - IGCC plant
physical or chemical methods. On the other side, scheme
industrial plant goal is to maximize productivity and
optimize operation cost; hence, the concept of
Watergy is becoming a fundamental for plant
managers. This expression describes the envelope
which includes water management and energy and
is becoming more and more popular in the industrial
market.
This paper will describe how advanced automation
technologies support an IGCC (Integrated
Gasification Combined Cycle) wastewater treatment
plant to comply with regulation and, at the same
time, to optimize operation and increase energy
efficiency. In particular, authors will describe how, by
mean of Model Predictive Control (MPC), an effective

IndustrIal Plants - May 2014
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