Plant Visitation to Assist Process Technology Selection
By Jerry Lacatena
Frequently when a refining company decides to pursue installation of a new
or unfamiliar process technology in their facilities, they go through
technology screening, bid solicitation, and rigorous technical and
commercial evaluations to arrive at the best choice. Part of the
evaluation may be to visit existing plants that are of similar design,
style, and capacity to the target design of interest. Sometimes the visit
may follow shortly after selection, if the client is more aware of the
licensor design specialties, issues, etc. In other cases, the visit may
occur before selection to assist in the decision process. The licensor or
contractor usually arranges visitation meetings and a unit walk-thru at
This article is only intended to provide general insights for potential
topics to include in a plant visitation, and can vary based on how
sophisticated/informed the visitors are. The expectation is that a site
visit agenda/questionnaire would be tailored to a specific technology,
licensor or contractor offering in advance, and be useful to capture
information gathered in a systematic way, particularly where more than one
site is involved.
Generally, the objectives of a visit are to better understand the unit
visited, how that may increase confidence in the licensor’s proposed
design for the client, and focus attention on potential
considerations/issues/desired provisions for potential investigation,
The visit agenda/questionnaire may also consider topics such as the
following, recognizing that these are illustrative rather than considered
- Did the plant commissioning and startup proceed as planned? Were
they aware of any areas where improvements would have facilitated
startup, such as training, licensor support, process design features,
mechanical design features, etc.?
- Did the unit meet performance guarantees during the initial test
run on design feedstock (i.e., product yield/quality, catalyst life,
etc).? How could operation be improved?
- How long has the unit been in operation, and what is the average
annual on-stream time?
- What were the major causes for downtime (i.e., process,
maintenance, equipment issues, utility issues, etc.)?
- What improvements could be considered to decrease downtime?
- What areas require the greatest attention (i.e., fouling,
corrosion, materials/fabrication, equipment, etc.)?
- What improvements could be considered to decrease/increase unit
run lengths or reduce turnaround duration, if any?
- What spare equipment was included in the design and why ( i.e.,
fouling, corrosion, safety, etc.)?
- Is the control system suited to the process for startup, normal,
and emergency operations?
- Was any issue encountered with control flexibility to establish
- Were any special safety controls implemented later?
- Does the unit produce pollutants which pose unusual, difficult
disposal, treatment, or monitoring issues?
- What special measures are required for waste disposal?
- What is the unit’s safety record, and what design features would
possibly make the unit safer?
Feed and Product Quality
- What is the range of feeds/properties that have been processed in
the last two years?
- How does the unit respond to changes in feed composition and
- What feed impurities and properties most affect product quality,
and how are they routinely analyzed?
- Were product specifications generally met, and what are the
products used for?
- What are the design capacity and turndown flexibility of the unit?
Has the unit performance been satisfactory with respect to these
areas? Have any bottlenecks been identified, or have the units proven
to provide more flexibility or capacity than originally expected?
- Were there subsequent modifications made to the unit and why
(i.e., bottlenecks, Encon, etc.)?
- What is the overall unit plot size?
- To what extent has the licensor or contractor been involved in
training, troubleshooting problems if any, and providing continuing
support? Is there a follow-up technical support agreement with the
- Were design packages complete, operating manuals adequate for
training, and analytical test methods sufficient?
Specific Technical Questions
- These would depend on the specific technology and licensor,
novelty and experience base of the process, and service application of
interest. Mature technologies may be more readily prepared than ones
that have been recently commercialized. Carmagen has technical
specialists who are familiar with virtually all areas of process
technology and issues of significance, and can assist clients with
process technology selection, site visits, and follow-up technical
support on behalf of the client as appropriate.
Clearly, the extent of information obtained during a site visit depends on
the openness of the site, confidentiality requirements, etc. But plant
visits are a useful approach that many refining companies take at the
appropriate stage of a project.