A BRUGG GROUP COMPANY
Project
In Gothenburg's oil harbor, Scandinavia's largest port and a central hub for maritime trade, Stena Oil acquired a bunker tank with a storage capacity of 10,000 cubic meters, bringing the company's total tank volume to over 100,000 cubic meters. Stena Oil operates its own bunker vessels in the port, supplying a wide range of ships with fuel, heating oil, lubricating oils, and other oil products. This strategic expansion increases security of supply and gives the company additional flexibility in the increasingly demanding maritime fuel trade.
In order to integrate the tank into ongoing operations, a high-performance heating system had to be installed. This was to ensure that oil products remain liquid even at varying outside temperatures. Conventional heating systems often lay long heating pipes in a serpentine pattern on the tank floor. However, this has the disadvantage of covering almost the entire floor, which makes cleaning difficult and leads to longer downtimes. The aim was therefore to find a solution that would heat the tank evenly and leave most of the bottom free.
BRUGG Scandinavia, formerly BRUGG Sweden, developed a system using NIROFLEX DN 50 a flexible, spiral-welded stainless steel pipe with high thermal transfer performance and mechanical strength. The high degree of prefabrication of these systems, for which BRUGG Pipes is renowned, enables particularly short installation and downtimes. A total of around 520 meters of piping was installed, divided into four self-contained heating circuits, which were delivered as prefabricated modules and assembled on site. The pipes run vertically along the tank walls. This causes the warm liquid in the tank to rise and the colder liquid to sink, resulting in uniform mixing. The free floor area makes inspections and cleaning much easier. Durch die Spiralform der Rohre wird die Heizfläche vergrössert, wodurch die Wärmeübertragung effizienter wird. Darüber hinaus erlaubt der modulare Aufbau eine Anpassung an variierende Medien, Betriebsdrücke und Temperaturanforderungen.
The project was initiated in 2021 but was postponed due to necessary structural renovations of the tank container and was finally completed in 2023. The planning and prefabrication phase took around four to five months, during which detailed design calculations, drawings, and logistical coordination were carried out. On-site installation was completed within a timeframe of around three weeks. An additional advantage of the new solution for the assembly operation was the reduced welding effort, as longer pipe lengths with fewer connection points could be used. The prefabrication of the heating modules significantly reduced assembly times and interface risks.
With the implementation of this heating technology, Stena Oil achieves increased thermal efficiency, shorter commissioning times after maintenance intervals, and a reduction in unplanned downtime. Die freie Tankbodenfläche führt zu einer messbaren Reduktion des Reinigungsaufwands und somit zu einer Senkung der Betriebskosten über den gesamten Lebenszyklus.
As the first installation of its kind in Sweden, the project highlights the potential of innovative pipe systems for applications in the maritime energy sector, particularly in terms of operational efficiency, ease of maintenance, and technical adaptability to changing market requirements.
Project
The Lochmead Dairy farm in Junction City, Oregon is a modern dairy cattle company, which today covers a large part of its power requirements with renewable Energy.
Since a suitable raw material is close by, in this case cattle manure, biogas can be produced on site to generate electricity that is delivered and sold to the local utility utilizing a proprietary anaerobic digestion process. For this purpose our customer, Revolution Energy Solutions LLC, constructed a biogas plant on the farm property. This plant consists of two digester tanks, an effluent storage tank, and a combined heat and power unit where the fermentation gas is converted into electricity and heat.
For optimum gas production both digesters must be maintained at a constant temperature. To maintain this temperature, external heat is required and is supplied by the cooling water of the power generator. The decision was made to use a wall mounted pipe heating system. After the evaluation of various pipe systems, the BIOFLEX system by BRUGG PIPES selected for its ease of installation and superior heat transfer capability. The BIOFLEX pipe is a
corrugated, flexible pipe made of 316L stainless steel and is made in “endless” lengths. This makes the installation of the pipe considerably faster than any other pipe and eliminates the Need for connections inside the digester that may leak down the road.
The only connections to the pipe are outside the digester. All of these facts supported the customer’s choice of the BIOFLEX pipe. Before the actual installation, the BIOFLEX system had to be adapted to the specific design of the digester. The digesters at this plant are made of glass‐fused steel sheets
that are bolted together. The supports for the pipe, also made in stainless steel, were designed such that they straddle one sheet height. This way the sheets and the pipe supports could be installed with the same tank bolts.
