Title : Optimizing loading pumps energy consumption at Saudi Aramco Abha & Jeddah plants
Abstract:
The Problem:
Plant hydrocarbon loading pumps are one of the main energy consumers responsible for delivering the fuels (diesel oil, PG-91 & PG-95) to the gas station customers under pre-determined flowrate to satisfy customers’ demand in safe and reliable manner. Each truck loading bay has two arms to load the customer’s truck where each one of them has flowrate of 1,800 Liter Per Minte (LPM), yielding to 3,600 LPM flowrate per bay. Furthermore, the existing operation philosophy of the loading process is that each two arms will send a command signal to start one pump. Meaning that, one loading bay will operate one pump, two loading bays will operate two pumps and so on. However, investigating the operation configuration with increased number of operating pumps, it was found that excessive and recycled flows are encountered which are more than the bays’ demands in terms of flowrate, imposing additional energy consumption and electrical burdens for Abha & Jeddah plants.
Successful Approach:
Comprehensive and holistic assessment was conducted to the loading system configuration and revealed that changing the pump demand’s sequence will satisfy the operational requirements in very effective and optimized approach. The initiative calls for operating one pump for every three arms demand in contrast with the previous setup, resulted in reducing the number of pumps in demand which will be realized whenever three loading bays or more are operated in parallel. Thus, after implementing the initiative, two pumps will be operated for three loading bays demand and three pumps will be operated for four loading bays demand and so on. The assessment was the driver for the implementation of the initiative where pumps’ performance curve has been examined across the proposed change in the delivered flowrate to ensure pumps will not operate outside the allowable range from Best Efficiency Point and as permitted by API. Moreover, vibration analysis was carried out during the execution of the initiative to confirm there is no abnormality observed while in pumps are operation. As a result, pumps were found to be satisfactory in terms of performance considering the new proposed set-up in addition to meeting the customer’s daily demand.
Positive Outcomes:
The initiative has contributed significantly to enhancing the operation of loading pumps for the respective plants without imposing any financial burdens on the department cost sheet. It optimizes the energy consumption of the pumps as there will be fewer operating pumps per demand. Moreover, it improves the reliability and availability of the pumps as there will be more standby pumps. Furthermore, it minimizes the excessive recycled flow resulted from operating more pumps than required. It is anticipated that the implementation of the initiative at Abha & Jeddah plants will lead to an annual energy saving of 1.11 million KWh with equivalent to an anticipated annual cost saving of $ 95,000. Moreover, it will result in 745 tons of CO2 emission reduction.
