A device for detecting build-up of deposits on pipeline walls was developed recently by Cybernétix and Institut Francais du Petrole, in partnership with Total. It was then tested early last year for 100 days on an onshore production line operated by Geopetrol, in southwest France.
The detectors are installed on the outer wall of the pipeline and are linked to the same acquisition system. The system for detecting deposits is based on a simple thermal principle: a defined quantity of heat is injected for a short given time, using a heat source, while a sensor records the thermal responses.
A one-hour measurement cycle is imposed, including five minutes of heating, with recordings every two seconds, repeated every hour during the time of the campaign. The measurement data acquired by both deposit detectors are processed in real time by a computerized method to give the deposit thicknesses. The method is derived from the modelling of heat transfer in the pipeline wall and fluid in various conditions.
This product is intended to be an efficient, non-intrusive sensor both for the detection of wax formation, and for control of wax removal. In addition, measurement of wax thickness allows optimization of the pigging operation schedule and a reduction of chemical inhibitors.
The trial program results revealed that the wax appearance temperature (WAT) of the produced oil was 28°C, while a deposit sample exhibited a WAT of 53°C.
Cybernétix is proposing this product as a turnkey system, comprising a sensor clamp package and the associated monitoring computer running the acquisition software and the IFP thickness calculation model. Cybernétix also proposes offering the deposit detection system on a project management basis, including detailed engineering, procurement, construction, and all the associated services from site installation to commissioning, start-up and maintenance.
