Methods and systems for spillback control of in-line mixing of hydrocarbon liquids

A method of admixing one or more hydrocarbon liquids, petroleum liquids, or renewable liquids, the method comprising:

• blending two or more liquids of the one or more of the hydrocarbon liquids, petroleum liquids, or renewable liquids, at least one of the two or more liquids being stored in a tank of a first set of tanks and at least another of the two or more liquids being stored in a tank of a second set of tanks, each tank of the first and second sets of tanks being connected to one or more blend pipes to blend the two or more liquids into a blended liquid;
• determining or measuring a first flow rate of the one or more liquids flowing from the first set of tanks into the one or more blend pipes;
• determining or measuring a blend flow rate of the blended liquid in the one or more blend pipes;
• determining a second flow rate of the one or more liquids flowing from the second set of tanks into the one or more blend pipes;
• and
• in response to a difference between a target ratio and a ratio of the first flow rate to the second flow rate:
• determining ratio adjustments for the first flow rate relative to the second flow rate, and
• adjusting one or more control valves based on the ratio adjustments, to modify a first spillback flow rate of a flow of the one or more liquids from the first set of tanks recirculated in a first spillback loop and the first flow rate to drive the ratio towards the target ratio.

A method of admixing one or more hydrocarbon liquids or renewable liquids, the method comprising:

• blending two or more liquids of the one or more of the hydrocarbon liquids or renewable liquids, at least one of the two or more liquids being stored in a tank of a first set of tanks and at least another of the two or more liquids being stored in a tank of a second set of tanks, each tank of the first and second sets of tanks being connected to one or more blend pipes to blend the two or more liquids into a blended liquid;
• determining a target blend ratio of one or more liquids flowing from the first set of tanks into the one or more blend pipes and one or more liquids flowing from the second set of tanks into the one or more blend pipes;
• measuring a first flow rate of the one or more liquids flowing from the first set of tanks into the one or more blend pipes;
• measuring a blend flow rate of the blended liquid in the one or more blend pipes;
• determining a second flow rate of the one or more liquids flowing from the second set of tanks into the one or more blend pipes;
• determining a first spillback flow rate of a flow of the one or more liquids from the first set of tanks when recirculated in a first spillback loop positioned upstream of the one or more blend pipes;
• and
• adjusting the first flow rate based on the first flow rate, a target first flow rate, and the first spillback flow rate.