class HeatExchangerNetwork(ID='', T_min_app=5.0, units=None, ignored=None, Qmin=0.001, force_ideal_thermo=False, cache_network=False, avoid_recycle=False, acceptable_energy_balance_error=None, replace_unit_heat_utilities=False)[source]#

Create a HeatExchangerNetwork object that will perform a pinch analysis on the entire system’s heating and cooling utility objects. The heat exchanger network reduces the heating and cooling utility requirements of the system and may add additional capital cost.

  • ID (str) – Unique name for the facility.

  • T_min_app (float) – Minimum approach temperature observed during synthesis of heat exchanger network.

  • units (Iterable[Unit], optional) – All unit operations available to the heat exchanger network. Defaults to all unit operations in the system.


Original system stream and heat exchanger objects are preserved. All stream copies and new HX objects can be found in a newly created flowsheet ‘<sys>_HXN’ where <sys> is the name of the system associated to the HeatExchangerNetwork object.



>>> import biosteam as bst
>>> bst.settings.set_thermo(['Water', 'Methanol', 'Glycerol'])
>>> feed1 = bst.Stream('feed1', flow=(8000, 100, 25))
>>> feed2 = bst.Stream('feed2', flow=(10000, 1000, 10))
>>> D1 = bst.ShortcutColumn('D1', ins=feed1,
...                     outs=('distillate', 'bottoms_product'),
...                     LHK=('Methanol', 'Water'),
...                     y_top=0.99, x_bot=0.01, k=2,
...                     is_divided=True)
>>> D1_H1 = bst.HXutility('D1_H1', ins = D1.outs[1], T = 300)
>>> D1_H2 = bst.HXutility('D1_H2', ins = D1.outs[0], T = 300)
>>> F1 = bst.Flash('F1', ins=feed2,
...                outs=('vapor', 'liquid'), V = 0.9, P = 101325)
>>> HXN = bst.HeatExchangerNetwork('HXN', T_min_app = 5.)
>>> sys = bst.System.from_units('sys', units=[D1, D1_H1, D1_H2, F1, HXN])
>>> sys.simulate()
>>> # See all results
>>> round(HXN.actual_heat_util_load/HXN.original_heat_util_load, 2)
>>> abs(HXN.energy_balance_percent_error) < 0.01
>>> HXN.stream_life_cycles
[<StreamLifeCycle: Stream_0, cold
    life_cycle = [
            <LifeStage: <HXprocess: HX_0_2_hs>, H_in = 5.75e+06 kJ, H_out = 4.25e+07 kJ>
            <LifeStage: <HXutility: Util_0_hs>, H_in = 4.25e+07 kJ, H_out = 7.09e+07 kJ>
    ]>, <StreamLifeCycle: Stream_1, cold
    life_cycle = [
            <LifeStage: <HXprocess: HX_1_4_hs>, H_in = 0 kJ, H_out = 3.34e+04 kJ>
            <LifeStage: <HXprocess: HX_1_2_hs>, H_in = 3.34e+04 kJ, H_out = 5.39e+06 kJ>
            <LifeStage: <HXprocess: HX_1_3_hs>, H_in = 5.39e+06 kJ, H_out = 2.46e+07 kJ>
            <LifeStage: <HXutility: Util_1_hs>, H_in = 2.46e+07 kJ, H_out = 2.79e+08 kJ>
    ]>, <StreamLifeCycle: Stream_2, hot
    life_cycle = [
            <LifeStage: <HXprocess: HX_0_2_hs>, H_in = 4.52e+07 kJ, H_out = 8.46e+06 kJ>
            <LifeStage: <HXprocess: HX_1_2_hs>, H_in = 8.46e+06 kJ, H_out = 3.1e+06 kJ>
            <LifeStage: <HXutility: Util_2_cs>, H_in = 3.1e+06 kJ, H_out = 1.14e+06 kJ>
    ]>, <StreamLifeCycle: Stream_3, hot
    life_cycle = [
            <LifeStage: <HXprocess: HX_1_3_hs>, H_in = 2.18e+07 kJ, H_out = 2.6e+06 kJ>
            <LifeStage: <HXutility: Util_3_cs>, H_in = 2.6e+06 kJ, H_out = 2.6e+06 kJ>
    ]>, <StreamLifeCycle: Stream_4, hot
    life_cycle = [
            <LifeStage: <HXprocess: HX_1_4_hs>, H_in = 7.51e+05 kJ, H_out = 7.18e+05 kJ>
            <LifeStage: <HXutility: Util_4_cs>, H_in = 7.18e+05 kJ, H_out = 7.18e+05 kJ>
line: str = 'Heat exchanger network'#

class-attribute Name denoting the type of Unit class. Defaults to the class name of the first child class

heat_utilities: list[HeatUtility, ...]#

All heat utilities associated to unit. Cooling and heating requirements are stored here (including auxiliary requirements).

power_utility: PowerUtility#

Electric utility associated to unit (including auxiliary requirements).

F_BM: dict[str, float]#

All bare-module factors for each purchase cost. Defaults to values in the class attribute _F_BM_default.

F_D: dict[str, float]#

All design factors for each purchase cost item in baseline_purchase_costs.

F_P: dict[str, float]#

All pressure factors for each purchase cost item in baseline_purchase_costs.

F_M: dict[str, float]#

All material factors for each purchase cost item in baseline_purchase_costs.

design_results: dict[str, object]#

All design requirements excluding utility requirements and detailed auxiliary unit requirements.

baseline_purchase_costs: dict[str, float]#

All baseline purchase costs without accounting for design, pressure, and material factors.

purchase_costs: dict[str, float]#

Itemized purchase costs (including auxiliary units) accounting for design, pressure, and material factors (i.e., F_D, F_P, F_M). Items here are automatically updated at the end of unit simulation.

installed_costs: dict[str, float]#

All installed costs accounting for bare module, design, pressure, and material factors. Items here are automatically updated at the end of unit simulation.

equipment_lifetime: int | dict[str, int]#

Lifetime of equipment. Defaults to values in the class attribute _default_equipment_lifetime. Use an integer to specify the lifetime for all items in the unit purchase costs. Use a dictionary to specify the lifetime of each purchase cost item.

run_after_specifications: bool#

Whether to run mass and energy balance after calling specification functions

prioritize: bool#

Whether to prioritize unit operation specification within recycle loop (if any).

parallel: dict[str, int]#

Name-number pairs of baseline purchase costs and auxiliary unit operations in parallel. Use ‘self’ to refer to the main unit. Capital and heat and power utilities in parallel will become proportional to this value.

responses: set[GenericResponse]#

Unit design decisions that must be solved to satisfy specifications. While adding responses is optional, simulations benefit from responses by being able to predict better guesses.