Debotlenecking.
A partir de los balances de materia y energía PPS simula los procesos
para identificar límites y restricciones. Con los resultados propone las modificaciones
necesarias para incrementar la capacidad de procesamiento de la planta, los rendimientos,
mejorar la calidad de productos y optimizar el uso de energía. Resulta frecuente que esto
se logre implementando mínimas modificaciones.
Expansiones de capacidad. Si resultado del análisis “Debotlenecking” se observa que los
equipos ya no pueden dar la capacidad requierida, entonces PPS balancea el tamaño de
los equipos, consumos de servicios y especificación de productos para lograr una
expansión de la capacidad. solución integral que garantice el tiempo de inactividad mínimo
Retrofitting and revamping. Refers to making suitable changes and/or additions to existing
process configurations and equipment. It may involve new technology such as membrane
separation or reactive distillations to supplement or replace distillations. One example of
equipment and configurations changes in a process is heat exchanger network retrofitting,
which involves area additions in existing exchangers and/or installation of new exchangers
for increased energy recovery and re-use. Obviously, process retrofitting and revamping
should maximize the use of the existing equipment in the plant as much as possible.
Analysis, simulation and optimization techniques could be used to achieve the chosen
objective of the process retrofitting/revamping. However, process retrofitting/revamping
is more than operation optimization because the former considers changes to the process
configuration and equipment in addition to operating conditions. Hence, solving a process
retrofitting/revamping problem and implementing the solution found are more complex
and challenging than those in the case of operation optimization.
Con una filosofía de control adaptada al proceso y al nivel de complejidad, lo cual requiere
Con válvulas de control seleccionadas, para manejar sin intervención del operador
cambios en la alimentación o en el suministro de servicios, siendo rigurosamente
simuladas las distintas condiciones extremas en las que deberá operar la planta.
Chemical Process Retrofitting and Revamping: Techniques and Applications
edited by Gade Pandu Rangaiah
reequipamiento y modernización. Se refiere a hacer cambios y / o adiciones adecuadas a las
configuraciones actuales de los procesos y equipos. Puede tratarse de nuevas tecnologías, como la
separación de membrana o destilaciones reactivas para complementar o sustituir destilaciones. Un
ejemplo de equipos y configuraciones de los cambios en un proceso es intercambiador de calor de
reequipamiento de la red, que implica adiciones de área en los intercambiadores y / o instalación
de nuevos intercambiadores para una mayor recuperación de energía y re-uso existentes.
Obviamente, reequipamiento proceso y renovación deben maximizar el uso de los equipos
existentes en la planta tanto como sea posible. Las técnicas de análisis, simulación y optimización
se podrían utilizar para lograr el objetivo elegido del proceso de reequipamiento / renovación. Sin
embargo, el proceso de reequipamiento / renovación es más que la optimización de la operación
porque el primero tiene en cuenta los cambios en la configuración del proceso y equipo, además
de las condiciones de funcionamiento. Por lo tanto, la solución de un proceso de reequipamiento /
renovar problema y aplicar la solución encontrada es más complejo y desafiante que aquellos en el
caso de la optimización de las operaciones.
Retrofitting: How to have successful
revamps in stead of failed projects
Starting a successful revamp(Return to Contents)
Successful revamps require many different elements [2]. Nevertheless, starting on
the right path at the beginning tremendously improves success rates. The two
starting elements are (1) building the right revamp team and (2) understanding
current operation.
First, a brief review of team importance: "In the final analysis, people, not
procedures, make a project successful." [3] Never forget this point, and do anything
it takes to get the right people for your job: especially in a revamp. Procedures only
account for standard situations. By definition, revamps are not standard situations.
Limits and capabilities of the existing plant must be recognized and used. Every
plant is different. None fits a standard mold. Depending on people, supported by
sound engineering principles, not on mindless application of procedures, is the
basis for success in a fast-track retrofit.
Second, the current operation of the plant needs understanding. Every plant is
different. Every facility has different limitations and spare capabilities. These can
vary greatly from the calculated values of how the plant is supposed to run based
on paper documentation. Plant testing defines the current plant performance.
Analysis of plant performance identifies real limits and potential in the unit.
Insist on a plant test. Plant testing is vital to a successful revamp. Examining
performance of the real process and equipment surpasses the usefulness of any
modeling or engineering calculations. The basic techniques for successful revamps
all hinge on plant test results [4].
Good test run data identifies areas of concern for the retrofit team as well as
potential areas to avoid investment and modifications. To assure that an effective
revamp, the owner must realize (1) necessity of the plant test and be prepared to
pay for it in money, personnel commitment, and time and (2) insist that all
organizations involved take it seriously.
Moving from the plant test to conceptual design(Return to Contents)
Plant test analysis allows for meeting objectives with minimum modifications.
Minimum modifications reduce investment and cost. Every item that does not have
to be changed is one less thing to pay for or to have to execute during a turnaround.
How do you minimize the amount of work required in the plant while making sure
that you modify everything that must be done? The answer is simple, have a very
good defined plant test of the existing operation and test operations on all the
major equipment items.
Plant tests identify required changes early in the revamp work. From the test run
data, the first step should be a prompt evaluation of major equipment items and
utility systems. By major equipment items and utilities we include:
Large vessels (towers, major drums, tanks)
Rotating machinery (compressors, pumps, centrifuges, blowers, fans, filters)
Fired heaters
Special alloy equipment (Monel, Hastelloy, tantalum, titanium, zirconium)
Steam, electricity, water, fuel supply
Detailed engineering is not required at this point. What the revamp team requires
for this step are experienced engineering generalists. The evaluating engineer must
understand operations, equipment design, and procurement to an extent to make
an informed and prudent engineering judgment with limited information.
Equipment specialists should become involved as needed. When pushing the limits
of equipment, problems encountered only rarely in normal types of operations may
occur. The main questions to answer are "What is the limit of the existing shell,
casing, fire box, or other major constraint?" and "What is the ultimate limit of that
size item in this service?" Answers to these questions define the major
modifications required.
As an alternative to straight replacement of major equipment items, modifications
to the process flow scheme should be evaluated at this stage. Process flow scheme
modifications can often selectively unload flows from one equipment item to
another.
Integrating process scheme changes and equipment modifications and service
changes generates the conceptual process to meet the revamp objectives. The plant
test analysis and data again play a pivotal role. Knowing what true capabilities are
available, the benefit of modifying process changes can be accurately determined.
Without plant test results, changing the process becomes a hit-or-miss affair with
high risk. Plant test results minimize technical risk and assure the most effective
revamp process scheme.
