In a nutshell

Furnaces being a vital part of the refining process, monitoring their integrity is critical for any facility, as was the case at the Refidomsa facility in the Dominican Republic. This brief case study reviews the utilization of an Electromagnetic Transducer (EMAT) technology-based Circumferential Hand Scanning Tool (CIRC) in combination with visual inspection and ultrasound (UT) imaging for a comprehensive inspection of two furnaces.

The Dominican Petroleum Refinery, Refidomsa, processes around 30 million barrels of crude oil per year and currently holds over 60% of the hydrocarbon market share in the Dominican Republic. Located close to the Haina Occidental Port, this refinery is responsible for processing all of the crude oil that enters the country. This means that the Refidomsa refinery produces approximately 34,000 barrels of refined product per day. Given the large throughput of this facility, it is of utmost importance to Refidomsa that all parts of the facility maintain their integrity and remain safe for operation.
One part of the facility that requires integrity inspection are the fire heating furnaces, specifically the heating coils inside the furnace units. These furnaces are an essential part of the refining process where the product passes through internally and is heated to a specific temperature by direct fire, undergoes further transformation in the reactors, or is separated by distillation to obtain diverse kinds of final products, such as gasoline, diesels and fuel oil. Due to the high volume demands of the facility, the operator required minimal downtime of the furnaces. The inspections must be performed efficiently and within a tight schedule of previously-planned shutdown segments in order to avoid a complete shutdown of the facility and minimize associated risks. The demanding inspection parameters required extensive pre-inspection planning and a high level of trust in the expertise of the ROSEN team.

Through close cooperation with the Refidomsa, ROSEN integrity engineers evaluated the asset, identified the inspection requirements and formulated a plan, which included visual and technical inspections, to assess the status of the furnaces.
First, visual inspections were performed to identify areas of concern. Then, the ROSEN Circumferential Hand Scanning Tool (CIRC) was used to identify anomalies. The CIRC system is an external inspection system that utilizes Electromagnetic Transducer (EMAT) technology. The CIRC tool provides a differential gauge unit, measuring any change in the acoustic path through two acoustic transducers, which can detect any changes in material through a significantly long acoustic path. The tool delivered full data coverage of the heat exchanger coils within the furnaces. The data from the CIRC inspection was downloaded and then confirmed using the images collected via an ultrasonic (UT) hand scanner. All of this collected information was consolidated in a report for Refidomsa.
Combining EMAT technology with UT and visual inspection of the heat exchangers enabled the operator to obtain information on all areas of the furnaces, including the difficult to access areas and even some so-called “blind zones.” This combination of inspection technologies provided a complete and comprehensive understanding of the integrity status of these installations.

In order to avoid unnecessary downtime, the inspections were performed within an eight-hour shutdown window. In total, 271 tubes and 60 bends, in two furnaces, were inspected.
The inspection was completed within the agreed-upon time frame and delivered high-quality data to the satisfaction of Refidomsa. The operator gained valuable information on the integrity status of the furnaces, with limited shutdown of operations, enabling further safe, efficient, and compliant future operations.