In Spec In-Line Blender
A Refinery In-Line Blender that utilized knock engines and NIR analyzers was run in manual control for years. The track record of automatically blended batches meeting spec was spotty at best, with significant re-blend costs. The resulting practice of overcompensating octane give-away cost the plant significantly.

A Blender Control System with new and re-used NIR analyzers (and without knock engines) was installed and commissioned with minimum downtime. Mangan was selected for the project, and the careful design and thorough commissioning, tuning and training resulted in automatic blend runs with a lower tolerance than had been hoped for. The Blender runs reliably and the Refinery is benefiting with the ability to meet Clean Fuel Specs with reduced capital requirements.



Gas Plant GC Resurrection
A Gas Chromatagraph measuring 8 streams (5 gas, 3 liquid) as a part of a closed loop control scheme had been bypassed with all loops placed in manual for an extended period of time. The analyzer was no longer supported by the original vendor, and the local technicians had reached their limit of spare parts and capabilities.

Mangan analyzer staff re-engineered and re-built the sample systems and analyzer using adapted off-the-shelf parts. We added another stream measurement, calibrated the analyzer, and re-commissioned and tuned the associated control systems, allowing the gas plant throughput to increase 4%. The increased yield paid for the work in less than one month. The operating company is moving forward with audits and re-builds in the remaining plants.



(5) SIS in (5) Weeks
A Refinery expedited a series of Capital Projects as a result of a fire repair effort. The projects had hoped to include upgraded Safety Instrumented Systems. The design of the systems benefited from standards mutually established by the Client and Mangan staff. These simplified the design process to the point of check-box data sheets for the majority of the installation. With this efficient basis for design, Mangan engineered, tested and commissioned (5) new systems in the (5) week re-building period.



Terminal Vapor Recovery System Repair
A Pipeline Company Marine Terminal Vapor Recovery system, consisting of (9) PLC’s networked to a local control room, had operated unreliably for an extended period of time. The resulting downtime had caused serious demurrage charges for the tanker operators, jeopardizing the Terminal business.

Mangan reverse engineered the process and mechanical configuration along with the process controls. (9) bed-sheet logic diagrams and associated P&ID’s were generated to display the programmed control system. Operations found a list of surprises that could have accounted for the unreliable operation. Remediation steps were defined and installed, and the system has operated reliably since. Additionally, a comprehensive document and training package was assembled to enable the facility to manage continuous operations in the future.


Alky Refrigeration Compressor Tune-up
A Major Refrigeration Compressor had been tripping unexplainably, and operating in and out of recycle for years. The recycle flow was so loud it could be heard driving through the refinery gate. Repeated attempts to diagnose the problems had failed, and the Alkylation Unit was running at a reduced rate to compensate for the unpredictable operation.

Mangan staff installed high resolution recorders on a dozen process variables, and a careful review of controller installation and configuration was conducted. The investigation revealed process pockets that caused icing, limiting tuning constants that choked a cascaded flow loop, and floating ground loops that could produce signal errors. The easier Remediation efforts were prioritized, and with minimal effort the compressor recycle valve closed and the compressor ran reliably.



FCC PRT Trips
An FCC Power Recovery Train Project installed a large Variable Speed Drive on the turbine generator. The system was installed and commissioned by a blended E&C team, but was immediately plagued by unexpected trips. For a year efforts were made to diagnose the cause. In the meantime the drive was operated in manual mode, reducing the optimized operation that had justified much of the capital investment.

Mangan staff installed high resolution recorders on key proves variables and immediately (the same day!) discovered safety system diagnostic circuits that were generated on digital output circuits. These had electronic interposing relays with very low coil burdens that were being "bumped" by the diagnostic circuits. Suitably specified electro-mechanical relays were installed to replace these, and the system has operated reliably in automatic mode since.