Successful upgrade to Rabigh II refinery

When there is a power outage at a refinery the size of Rabigh II, the impact is more than just high costs for the plant operator. After a power failure it is therefore essential to get the power station back in service as quickly as possible; using three black start diesel generators.

The challenge with this project was to implement a cost effective and reliable solution with high availability and compatible with local conditions. The refinery, located in the desert on the edge of the Red Sea, is largely surrounded by sand. The client therefore specified IP55 ingress protection to guard against harmful sand deposits inside equipment and provide complete touch protection. For HPS it was additionally important to be able to build the necessary control cabinets for the emergency generators in-house in order to maximise their internal value-added chain.

The refinery upgrade was the first project in the Middle East for the Asian prime contractor. Putting pressure on other companies involved in the project with regard to quality and delivery times. Within its scope of delivery, HPS relied on internationally proven partners such as Eaton. “Eaton's products are globally known and accepted. That was a strong selling point for this project, as always”, according to Bernd Mähnss, Managing Director of HPS.

The three black start emergency generators are located in the power house, each connected to the medium-voltage system through its own control unit. Each generator needs a motor control centre (MCC) for the auxiliary drives, amounting to some 20 motors for various pumps and fans. For this, HPS chose Eaton's xEnergy technology with IP55 ingress protection. As an xEnergy partner, HPS is licensed to build the switchboard system in-house, so it fulfils the company's requirements for maximising internal value creation. HPS opted for the withdrawable version to meet the requirement for extremely high availability in the event of a grid outage.

The MCC solution is designed with a suitable spare module for each power stage in the system. If a module becomes defective, a service technician can withdraw it without any sort of special tool and replace it with the spare module. The key advantages of this are that replacement takes only a few seconds so the auxiliary drive is quickly available again, the defective auxiliary drive module can be repaired immediately, and only the drive concerned has to be switched off instead of the entire system. This also makes an important contribution to boosting cost effectiveness. “Given the specified requirements, the xEnergy system, with its good functionality, easy handling and modern design, was a perfect fit for this project”, says Mähnss. “This was our first project with xEnergy withdrawable modules, and together with Eaton we developed a solution that got us to our target.”

HPS completed the project successfully, and on time, in roughly nine months. “The system has been commissioned and accepted by the customer, and now it's ready to go”, says Mähns “in cooperation with the prime contractor, who did a very good job of project management, we were able to fulfil our tasks perfectly with xEnergy, and we are pleased with how smoothly things went and our successful contribution to this international project.”

The Rabigh II refinery has a reliable and high availability drive control system for the emergency generators that is able to restart the steam turbines of the power station in the event of an emergency.

“We developed a solution that fully meets the customer's requirements and our own requirements”, notes Mähnss. “We use Eaton products to give our customers security, because they have never let us down. xEnergy is an especially good solution for us because it lets us put together versatile systems, build the modules ourselves and adapt them flexibly to meet customer requirements. In future we will continue to rely on Eaton technology and jointly implement many more projects in Germany and at the international level.”

Read the article online at: https://www.hydrocarbonengineering.com/refining/30092016/successful-upgrade-to-rabigh-ii-refinery/