Requirements for the management of liquid petroleum products are specific to an individual company that operates a bulk storage facility. The following provides an overview of the operations performed at many oil and gas facilities.
Inventory Control or Custody Transfer
Inventory control is a term used to describe the management of inventories that generally do not change ownership when they are moved or used. Custody transfer implies two parties have an agreed upon system for accurately measuring the amount of product transferred. The system is often specified and approved by authorities, such as NMI, to international accepted standards for assessment of taxes or duties. A tank gauging system may be selected based on accuracy, repeatability or the ability to perform multiple measurements, such as temperature or density profiles. Tank gauges may not even be integrated into an inventory system, instead the gauge may only provide level outputs to alarm, relay or other host systems.
Product Movements and Operations
The logistics process is used by facility operators to plan daily activities. Here, instrument reliability and repeatability is often more important than absolute accuracy. Complete integration and functionality to view and track all product movement totals, discrepancies and supervisory control of pumps and valves may be required. This could include obtaining tank-to-tank transfers, charges, shipments, receipts, yields (rundowns), water drains and blends with the ability to compare this data, archive and print reports.
Accounting and Reconciliation
Oil & gas facilities often need to accurately manage transactions and reconcile book versus physical inventory.
Generally, companies need to see the beginning daily book inventory, all configured transactions by day, the end of day physical inventory and the gain/loss for each day and month. They need to see this data for a selected product or transaction type. Every company is accountable; reconciliation, error reporting and query tools should also provide the auditing and traceability that is often required. Integrating instruments and systems will allow the immediate data acquisition and response required for accurate daily accounting and reconciliation.
As the industry is becoming more aware of the impact of overfills, leaks and emissions of environmentally damaging product, programs are initiated to reduce the risks and comply with international, national and local environmental regulations. Bulk storage facilities primarily look for a system to provide and manage alarms and detect leaks that can integrate with instruments already installed. Without a specific leak detection system, long term historical data can be analyzed to identify possible leaks or calculate emissions, but extensive custom reporting is often required.