Boushehr Petrochemical

Sweet Sweetening Production


Bushehr petrochemical complex is set to be constructed in ASSALUYE economic special zone, with the capacity to produce one million tons of ethylene annually.

Gas feed is provided by south pars phases 6, 7 and 8. It is then processed in the sweetening plant, de-ethanizer, methanol and olefin plants.

Gas sweetening plant must utilize huge turbo-compressors to increase the gas pressure entering sweetening tower. In case of a problem in turbo-compressor performance, gas feed of all other plants is stopped. Therefore, it is vital to have the most reliable machines feed sweetening tower.

IGT25 is one of the most reliable machines, which is fully designed by Iranian experts in Turbotec Co.  The nominal power of IGT25 is 25,400KW in ISO condition. The turbine output power is drastically dropped due to high ambient temperature in South pars (48 °C). However, as a result of high technical modifications, IGT25 is able to serve a minimum power of 20,500KW in the most sever ambient condition of south pars.

To meet the client’s expectations, IGT25 has been customized for this project to increase the TBO (Time Between Overhaul) from 40,000 to 48,000 equivalent operating hours. In addition, IGT25 is coupled with a HRSG to produce low-pressure superheat steam for natural gas process.

On the other hand, the client insisted on API 616, 5th edition full compliance. Therefore, some parts / sensors have been changed to fulfill the client’s requirement.

IGT25 is installed in BUSHEHR petrochemical complex as a combination of one + one (one turbo-compressor in operation and the other as spare one) with a common HRSG.

Turbotec has designed, implemented and test the IGT25 control system (Software and Hardware). The main characteristics of new control system are:

  • A completely new control configuration.
  • The first project started with National-Turbine software.
  • The first project started with Turbotec designed hardware.
  • HRSG logic change (Cold purge, Hot purge, …)
  • HMI (Human Machine Interface) modification

As a result of HRSG installation, the exhaust duct needs be rotated from vertical to horizontal position (see the figure above). Due to this rotation more than 900 parts, especially piping components have been modified.

All required documents and drawings have been prepared and sent to client as per VPIS (Vendor Print Index and Schedule).

VPIS included:

  1. Arrangement & Layout + General Documents
  2. All required P&IDs for machine, Auxiliaries and accessories
  3. Mechanical design and operational data
  4. System descriptions
  5. Instrument and electrical design and operational data
  6. Handling and Installation
  7. Maintenance and spare parts
  8. Quality, Performance, procedures and manufacturing
  9. Packing and shipping
All the required documents for HRSG design and operational data have been controlled, checked, verified and approved by Turbotec. However, the HRSG contractor has not issued any documents about the Diverter Damper, which controls the exhaust gasses passage. Both Turbo compressors were started on Feb. 2019 successfully.