A revamp project is one in which there is some new work but the majority of it involves more or less extensive modifications to an existing urea plant unit. For example revamping a urea plant by a replacement of a stripper or high-pressure condenser. The new stripper or high-pressure condenser would be in most cases not simply a one-to-one replacement but rather one that incorporates the latest design features and probably a larger type. Consequently, installing it all likely calls for considerable pipe and instrument modifications.
Since only the briefest time possible can be allowed for the existing unit to be shut down for the installation of the new stripper or high-pressure condenser, careful and detailed sequencing of the work is essential.
A revamp of any kind is a daunting task. The project goal is to add years to the lifetime of the facility, while minimizing production stoppages and to ensure that safety, health and environmental issues are all addressed. Timing and scope are constant challenges. Generally, a change in the scope on a revamp project impacts the schedule to an extent not experienced on a green-field or brown-field project.
Traditional work-process disciplines appear to fall short when it comes to challenges of a revamp project. Hopefully the answers to be found in the quest will enable new procedures and work processes that specifically address a revamp project.

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