Power generation from waste heat in integrated crude oil refining, aromatics, and utilities facilities

A method of recovering heat energy generated by a petrochemical refining system, the method comprising:

• circulating a first heating fluid through a first heating fluid circuit thermally coupled to a first plurality of heat sources from a first plurality of sub-units of a petrochemical refining system, the first plurality of sub-units comprising a hydrocracking plant;
• circulating a second heating fluid through a second heating fluid circuit thermally coupled to a second plurality of heat sources from a second plurality of sub-units of the petrochemical refining system, the second plurality of sub-units comprising a diesel hydrotreating reaction and stripping plant;
• circulating a third heating fluid through a third heating fluid circuit thermally coupled to a third plurality of heat sources of a third plurality of sub-units of the petrochemical refining system, the third plurality of sub-units comprising a CCR plant, a portion of the aromatics plants separation system, and a utility system sour water stripping plant;
• circulating a fourth heating fluid through a fourth heating fluid circuit thermally coupled to a fourth plurality of heat sources of a fourth plurality of sub-units of the petrochemical refining system, the fourth plurality of sub-units comprising an aromatics plant benzene extraction unit and a CCR/aromatics plant;
• circulating a fifth heating fluid through a fifth heating fluid circuit thermally coupled to a fifth plurality of heat sources of a fifth plurality of sub-units of the petrochemical refining system, the fifth plurality of sub-units comprising a para-xylene separation unit;
• generating electrical power through a power generation system that comprises an organic Rankine cycle (ORC), the ORC comprising (i) a working fluid that is thermally coupled to the first through fifth heating fluid circuits to heat the working fluid with the first through fifth heating fluids, and (ii) an expander configured to generate electrical power from the heated working fluid;
• actuating, with a control system, a first set of control valves to selectively thermally couple the first heating fluid circuit to at least a portion of the first plurality of heat sources;
• actuating, with the control system, a second set of control valves to selectively thermally couple the second heating fluid circuit to at least a portion of the second plurality of heat sources;
• and
• actuating, with the control system, a third set of control valves to selectively thermally couple the third heating fluid circuit to at least a portion of the third plurality of heat sources;
• actuating, with the control system, a fourth set of control valves to selectively thermally couple the fourth heating fluid circuit to at least a portion of the fourth plurality of heat sources;
• and
• actuating, with the control system, a fifth set of control valves to selectively thermally couple the fifth heating fluid circuit to at least a portion of the fifth plurality of heat sources.

A method of recovering heat energy generated by a petrochemical refining system, the method comprising:

• identifying, in a geographic layout, a first heating fluid circuit thermally coupled to a first plurality of heat sources from a first plurality of sub-units of a petrochemical refining system, the first plurality of sub-units comprising a hydrocracking plant;
• identifying, in the geographic layout, a second heating fluid circuit thermally coupled to a second plurality of heat sources from a second plurality of sub-units of the petrochemical refining system, the second plurality of sub-units comprising a diesel hydrotreating reaction and stripping plant;
• identifying, in the geographic layout, a third heating fluid circuit thermally coupled to a third plurality of heat sources of a third plurality of sub-units of the petrochemical refining system, the third plurality of sub-units comprising a CCR plant, a portion of the aromatics plants separation system, and a utility system sour water stripping plant;
• identifying, in the geographic layout, a fourth heating fluid circuit thermally coupled to a fourth plurality of heat sources of a fourth plurality of sub-units of the petrochemical refining system, the fourth plurality of sub-units comprising an aromatics plant benzene extraction unit and a CCR/aromatics plant;
• identifying, in the geographic layout, a fifth heating fluid circuit thermally coupled to a fifth plurality of heat sources of a fifth plurality of sub-units of the petrochemical refining system, the fifth plurality of sub-units comprising a para-xylene separation unit;
• identifying, in the geographic layout, a first power generation system, comprising:
• an organic Rankine cycle (ORC), the ORC comprising (i) a working fluid that is thermally coupled to the first through fifth heating fluid circuits to heat the working fluid with the first through fifth heating fluids, and (ii) an expander configured to generate electrical power from the heated working fluid;
• and
• a control system configured to actuate:
• a first set of control valves to selectively thermally couple the first heating fluid circuit to at least a portion of the first plurality of heat sources, a second set of control valves to selectively thermally couple the second heating fluid circuit to at least a portion of the second plurality of heat sources, a third set of control valves to selectively thermally couple the third heating fluid circuit to at least a portion of the third plurality of heat sources, a fourth set of control valves to selectively thermally couple the fourth heating fluid circuit to at least a portion of the fourth plurality of heat sources, and a fifth set of control valves to selectively thermally couple the fifth heating fluid circuit to at least a portion of the fifth plurality of heat sources;
• and
• identifying, in the geographic layout, a power generation system location to position the power generation system, wherein a heat energy recovery efficiency at the power generation system location is greater than a heat energy recovery efficiency at other locations in the geographic layout.