Industries: Offshore Marine [FPSO/FSO/FLNG]

Floating Production Storage and Offloading vessels, or FPSOs, are offshore production facilities that house both processing equipment and storage for produced hydrocarbons. The basic design of most FPSOs encompasses a ship-shaped vessel, with processing equipment, or topsides, aboard the vessel’s deck and hydrocarbon storage below in the double hull. After processing, an FPSO stores oil or gas before offloading periodically to shuttle tankers or transmitting processed petroleum via pipelines. The processing equipment aboard the FPSO is similar to what would be found atop a production platform. Usually built in modules, FPSO production equipment can consist of water separation, gas treatment, oil processing, water injection and gas compression, among others. Hydrocarbons are then transferred to the vessel’s double-hull for storage.

Crude oil that is stored onboard is frequently transferred to shuttle tankers or ocean barges going ashore, via a loading hose. Loading oil from the stern of the FPSO to the bow of the shuttle tanker is known as tandem loading. While gas is many times transferred to shore via pipeline or re-injected into the field to boost production

Heat Exchangers in FPSO

Heat exchangers, separators, scrubbers, compressors and other equipment units are critical for the proper operation of the processing plant. The hydrocarbon stream received at the first production separator is a mixed stream comprising oil, water and gas phase. This mixed stream is processed in order to separate the oil dominated, water dominated and gas phase. Insufficient cooling of the gas stream reduces compressor efficiency, insufficient heating results in lesser quantities of gas bubbling out in the 3 phase separators and also insufficient cooling causes lesser condensate extraction from scrubber units, upstream of the compressor units

Heat Exchanger Failure Mechanism:
  • Process corrosion
  • Process fouling
  • Stress corrosion cracking (SCC) of tubes
  • Steam/condensate corrosion/li>
Minimize future in-service tube failures.
Three main areas for improvement to minimize future in-service tube failures.
  • Tube testing
  • Retubing strategy
  • Design improvements.
Tube testing

Technologies for inspecting heat exchanger tubes are rapidly changing and continuously improving. Variance in test results depending on both the instrument and operator. The impact of human factors on non-destructive examination (NDE) performance is more prominent with the increased complexity and sophistication of today`s NDE techniques. Root cause analysis of some of the tube failures identified the need for reliable technicians and technologies. APRIS provides solution to tube inspection problems with important advantages to offshore industry by minimizing downtime and improving operational productivity.