Page 439 - Design of Simple and Robust Process Plants

426 Chapter 10 The Efficient Design and Continuous Improvement of High-quality Process Plants
10.3.2.1 Technology selection
Technology selection is a formal process to select the best technology for a competi-
tive plant. The selection should be done by a highly qualified team, which should
include process researchers, among other functions. The selection should be done
on all technologies (both internally and externally), even if a particular technology
cannot be licensed. The selection should include the economics as well as environ-
mental aspects. External bench-marking can be done with a company such as Solo-
mon Associates Inc. Before the final selection is made, a patent search needs to con-
firm if a certain technology may be applied at the location under consideration. The
technology selection will be of crucial importance for the long-term success of the
project.
Timing/documentation: the selection is made during the feasibility phase, and
documented in the basis for design.

10.3.2.2 Waste minimization
The objective is to reduce the waste stream and its environmental impact on the
facilities. Under environmental impact we must consider not only air, water and soil
pollution and off-site waste disposal, but also risks to the environment and nui-
sances such as noise, and sky-line pollution such as flares, plumes and tall construc-
tions. The priorities for reduction are:

. Prevention or reduction of waste production.
. Recycle or reuse of waste material internal or external of the facility.
. Treatment of waste streams (also called ªend of pipeº treatment).
Quantified environmental studies are subject to preparation during each phase of
the project from feasibility phase to demolition. The content of these studies should
have the following elements:
. The environmental requirements (internal as well as external) should be
inventoried and considered as mandatory. It would be wise to be prepared for
more severe requirements in case the local requirements are not yet at wes-
tern world standard. Be prepared that there is an ongoing evolution to more
severe global requirements.
. The studies should include an environmental balance, not only for the treat-
ment of the continuous waste streams but also for the final rest streams in
water and air. It should also include the waste solids and its final treatment
and disposal, periodic wastes such as spent catalyst, plant-fouling materials,
regeneration waste, and demolishing materials. Be aware that the continuous
process will always be subject to variations that may result in fluctuations in
the waste streams and its concentration.
. Evaluations of alternatives are required for good decision making, and also
for the authorities. The application of the best practical means is mostly used
as reference for the authorities.