Understanding the Software Options

PLANT DESIGN STAGE – SOME IDEAS ON HOW TO BE GREEN
• Properly apply the chemical engineering principles and take
an innovative approach to design the plant with some of the
following benefits: higher yields, reduced waste, lower operating
temperatures, reduced energy requirements and reduced
utilities use
• Properly apply inherent safety principles in the design, seeking
opportunities for substitution of dangerous materials, minimization
of inventories, moderation of the process conditions and so on
• Brainstorm about the most effective processes to achieve
the final result, including the potential for biotechnologybased
processes
• Develop uses for waste streams, for instance, as raw material or
as fuel in boilers
• Consider advanced control techniques that could contribute to
reduced energy consumption or to increased yields
• Consider process-intensification opportunities to maximize
throughput and minimize a unit’s plot space
• Perform state-of-the-art heat-integration studies by using the
most advanced software available
• Eliminate waste by design instead of designing for waste treatment
• Fully understand risks and previous accidents associated with
the same or similar technologies or process routes, and design
accordingly
benefits, and there are tremendous
technical and business opportunities
in this area. One prime example is
the parallel efforts that are underway
worldwide to develop cost-effective
strategies for longterm carbon sequestration
(CO 2 removal and storage).
Other examples where R&D for green
efforts have the potential to create
large-scale business opportunities include
the use of renewable raw materials,
the production of biodegradable
plastics, the production of better batteries
for electrical vehicles, improved
insulation products, improved materials
for wind turbine blades, better
catalysts, use of CO 2 as raw material
for useful products [3] and more.
The box on p. 42 presents some specific
ideas related to “R&D for green.”
Green design
Green design in this case refers to
seeking opportunities for environmental
improvements when designing
CPI plants. Green design offers tremendous
opportunities for profit and
growth, but requires the right skills
and the right attitude. It requires
good understanding of the chemical
engineering fundamentals — kinetics,
thermodynamics, mass transfer, heat
transfer — and the capability to think
out of the proverbial box.
During chemical process design,
there is a significant advantage to
reducing or even eliminating waste
formation, not only from an environmental
viewpoint, but in terms of
improving yields and reducing asso-
ciated waste-treatment and disposal
— improvements that could offer significant
advantages in terms of profitability.
Consider the example of scrubbers,
which are intended to eliminate unwanted
emissions from being vented
to the atmosphere [7]. Scrubbers also
offer opportunities for further waste
reduction by either reusing the resulting
streams in the process or by redesigning
the entire process to reduce or
eliminate such vent streams. In other
words, scrubber applications illustrate
that there are several levels of green
that could be summarized as treat, reuse,
reduce and eliminate. As an example,
in a recent project undertaken
by one of the authors and his team, a
vent stream was successfully scrubbed
with a product from the unit and the
stream was recycled to the process
unit, which helped to minimize both
emissions and material losses.
The box above lists some specific
ideas on how to become greener in the
plant design phase.
Green operation
When talking about the operation of
chemical plants, there is a need to recognize
that any efforts to be green or
sustainable during R&D and design
phases will be in vain if the plants
themselves are not properly operated.
Additionally, in today’s era of tight
environmental scrutiny and high
expectations from customers, stockholders
and the general public, it is
unlikely that any chemical process
• Consider highly efficient processes and equipment (for instance,
the use of highly efficient boilers)
• Consider high-performance packing and trays for mass transfer
operations (to improve distillation, liquid-liquid extraction,
scrubbing and so on)
• Take steps to minimize or eliminate hazardous raw materials
and materials that are harmful to people or the environment
• Consider variable-speed drives to minimize energy consumption
•Consider the use of CO 2 streams, either as an inert gas in the
process or by binding it in the products
• Consider divided-wall columns and reactive distillation
• Consider fuel gas recovery and recompression in flare
systems
• Select adequate flowmeters to ensure that no waste or inefficiencies
are created because of improper flowrates
• Design plants taking into consideration potential changes to
product portfolios in the future (that is, be sure to build in some
flexibility)
• Consider automated blowdown for cooling towers (as reliance
on manual blowdown typically results in increased production
of wastewater and increased consumption of treatment chemicals
or system fouling)
• Design for maximum use of local materials of construction [1] ❏
company would be able to remain competitive
if it were not able to continuously
improve its operations in terms
of improved yields, reduced energy use
and improved waste reduction. Many
companies have demonstrated that
operating in an environmentally sustainable
manner provides a range of
tangible and intangible advantages.
A typical plant manager needs to
handle a large set of priorities, including
objectives and requirements
related to safety and environmental
performance, costs, production targets,
quality and so on. The push for
constant improvement is often focused
on helping the company or the facility
to become (or remain) the most efficient
producer in the market, in terms
of yield and waste, emissions and energy
consumption — all key metrics
that signal the health and competitive
position of the production process in
economic terms.
There are countless examples of the
payoffs that can result from the prudent
implementation of green initiatives.
By way of example, one of the
authors (and a team of colleagues) recently
received five awards related to
the successful implementation of innovative
ideas for waste and energy reduction,
which had significant impact
not only in terms of the environment
but in terms of improved profitability,
as well. There is always room for continuous
improvement on waste reduction
and energy optimization around
the plants, but the right combination
of attitude, creativity, motivation and
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