On budget, on time, offline
Flawless project execution will not prevent a unit shutdown due to selecting the wrong metallurgy for a challenging crude slate. No matter how well it is fabricated and installed, a shell and tube exchanger with cold, high viscosity vacuum resid on the tube side will have poor heat transfer performance.
On-time shipping and installation of a too-small desalter will not prevent crude column overhead corrosion if the centerline velocity is overly optimistic for the design crude.
A high labor efficiency factor for installation of tower internals will not increase vacuum resid cut point, but properly designed stripping trays will.
Managing major projects such as grassroots crude, coker, and FCC unit construction is hard work. Large revamps are even harder. In projects costing tens of millions to billions of dollars, detailed engineering and construction are monumental tasks that consume most of the overall project budget and schedule. As a project advances from a design on paper to steel on the ground, success requires relentless focus on meeting cost and schedule expectations, leading project management to seem an end in itself. However, the success of a project rests upon the foundation that is built during conceptual design and front-end engineering.
With surprising regularity, a unit’s failure to meet performance expectations does not stem from the detailed engineering and construction phases or faulty equipment manufacturing. Instead, project failure is often the result of poor front-end flow scheme design and initial process equipment specification.
A well-defined, early phase activity that consumes only a few percent of the overall project budget may seem trivial. In reality, solid front-end fl ow scheme development and equipment design are prerequisites for successful project execution. Rework and late stage process modifications usually reside at the top of the list of post-audit culprits in late and over budget projects.
Unit startup can quickly re-designate a project from shining success to haunting failure. Selecting a partner with an extensive experience list and a specialized understanding of the unit at hand can ensure startup goals are met while minimally impacting the overall project budget.
Oil sands crude — profits and problems?
Canadian bitumen production currently runs about 1 MMbpd, with some being sold as Synbit and Dilbit. Over the next 10-12 years output is expected to increase to 3.5 MMbpd and more refiners will begin investing to process it and come to depend on the Synbit and Dilbit for a significant part of their supply. ...
Heavy crudes are here to stay. As longs as oil prices remain high, Canadian, Venezuelan, Deep Water Gulf of Mexico, Mexican and other low API gravity crude oils will play an ever more important role in supplying world refineries. And prices promise to remain high because gainsayers notwithstanding, Hubbert ...
Designing deepcut vacuum units that really work
Every barrel of vacuum gas oil (VGO) you can save from being reduced to coke in the delayed coker unit is a barrel more that can go to the FCCU. That’s a good reason to raise HVGO cutpoint. But how to do it? Some people think the job can be done just by running computer models in the engineering ...
A time for grass roots thinking ?
Within the past year or two spiking crude prices and surging refinery margins have led to overheated talk about increasing refinery capacity worldwide. Plans for construction of as many 60 grass roots refineries have been discussed. But stretched out lead times for major equipment and inflated prices, ...
A single integrated vacuum system
Failure to design the vacuum unit as an integrated system will invariably result in unsatisfactory yield and poor product quality (high vanadium, nickel, microcarbon, or asphaltenes), and ultimately, an unscheduled shutdown. To avoid these revamp problems the charge pump, fired heater, transfer line, ...
Back in the late 1970’s and early 1980’s when fuel gas prices were high, energy utilization assumed major importance. A new method of calculating heat exchanger networks was developed. It was called Pinch Technology. Today pinch has been rediscovered by engineers who have access to fast computer ...
A group of interesting articles* deals with opportunity crudes, a mixed breed that includes very heavy, sour and high total acid number types as well as those with unexceptional naphthenic acid content but which do have significant concentrations of aliphatic acids or possess the ability to generate ...
Processing heavy Canadian crude
Reducing crude oil cost is the major incentive driving crude and vacuum unit projects to handle heavy Canadian crudes. But such crudes–Albian Heavy, Christina Lake, MacKay River and others derived from oil sands–today present refiners with a unique set of problems not just because of extra-low ...
Why do many crude/vacuum units perform poorly?
In many cases it’s because the original design was based more on virtual than actual reality. There is no question: computer simulations have a key role to play but it’s equally true that process design needs to be based on what works in the field and not on the ideals of the process simulator. ...
Why produce diesel from the vacuum unit?
Look ahead five years. The economy is likely to keep tightening and the rush to control pollution will inevitably be accompanied by demands for greater energy conservation. Consequence? A growing market for diesel which yields more energy per unit volume. Yet many continue to believe that producing diesel ...