Hardisty Cavern Storage Facility: Maximizing Process Equipment Utilization Through Innovative Automation Techniques

The Hardisty Cavern Facility at Hardisty, Alberta — consists of four underground salt caverns totalling 3.0 million barrels of petroleum products storage — was recently completed. This project is unique in that it integrates existing underground salt caverns into a significant North American crude oil transportation hub. Approximately 400 million barrels of oil move through this hub annually. This project utilizes existing caverns developed in the late 1960’s with significant upgrades and new infrastructure to integrate the Hardisty Cavern Facility into the crude oil transportation hub. This paper discusses the automation related innovations implemented and the challenges encountered during the course of the project. One example of innovation involves utilizing a single variable frequency drive (VFD) to perform multiple functions. Due to process requirements, the VFD was required to operate one or two cavern injection pumps. Electrical power grid constraints dictated that the VFD be used for starting and stopping the 1500 horsepower (1119 kW) pump motors. Process conditions also required that the pump motor loads be automatically transferred from VFD to the utility power grid without interruption to production. Operational flexibility was another key component of the facility automation requirements. Storage requirements for multiple petroleum products necessitated operator-selectable flow paths within the automation system. In addition, flexibility, safety, efficiency and maintainability requirements resulted in a distributed process philosophy across three separate process areas.