Patent Description:
Different tools and techniques may be utilized for refrigeration and/or heat pumping. There may be a need for new tools and techniques that may improve performance and/or efficiency.

Methods, systems, and devices for freeze point suppression cycle control are provided in accordance with various embodiments. Some embodiments are applicable in the field of refrigeration and heat pumping. Some embodiments pertain to control of freeze point suppression cycles. Specifically, some embodiments focus on the control of a temperature at which a freeze point suppression cycle may be able to absorb heat.

A further understanding of the nature and advantages of different embodiments may be realized by reference to the following drawings.

This description provides embodiments, and is not intended to limit the scope, applicability, or configuration of the disclosure. Rather, the ensuing description will provide those skilled in the art with an enabling description for implementing embodiments of the disclosure. Various changes may be made in the function and arrangement of elements.

Thus, various embodiments may omit, substitute, or add various procedures or components as appropriate. For instance, it should be appreciated that the methods may be performed in an order different than that described, and that various stages may be added, omitted, or combined. Also, aspects and elements described with respect to certain embodiments may be combined in various other embodiments. It should also be appreciated that the following systems, devices, and methods may individually or collectively be components of a larger system, wherein other procedures may take precedence over or otherwise modify their application.

Some embodiments provide for the control of a low temperature inside a freeze point suppression cycle. Some embodiments involve the integration of multiple components coupled with a controller that may that automatically control the cycle temperature via electrical signals and automatic control loops.

Some embodiments include a low concentration side sensor, a flow modulator, and a controller. Some embodiments may also include a high concentration side sensor and one or more pumps.

The controller, such as a processor, may receive one or more signals from one or more components and may send signals to the one or more components, which may maintain a useful temperature inside the freeze point suppression cycle's mixing tank, for example. This temperature's usefulness may be categorized namely by being below the melting point of the solid used in the freeze point suppression cycle. In some embodiments, the controller's goal may be to maintain a temperature as far below the pure freeze point of the solid used in the cycle as the user inputs; this may create useful refrigeration by the temperature difference between the pure freeze point and freeze point created by the mixture of the solid and the freeze point suppressant.

The physical process used by the controller may include modulating the flow through a separation system, which may concentrate a freeze point suppressant in order to maintain a concentration inside the mixing tank. To this end, the controller may capture the condition on the low concentration side of the cycle and the high concentration side in order to operate the separation system appropriately and maintain a low temperature, for example.

Turning now to <FIG>, a system <NUM> is provided in accordance with various embodiments. System <NUM> may be referred to as a freeze point suppression cycle control system. The system <NUM> may include a first sensor <NUM> positioned to determine an indicator value of freeze point suppressant property of a liquid <NUM>; the liquid <NUM> may include a mixture of a melted solid and a freeze point suppressant. The system <NUM> may include a flow controller <NUM> that may be utilized to control a flow of the liquid <NUM> to a separator <NUM>. The system <NUM> may include a controller <NUM> coupled with the first sensor <NUM> and with the flow controller <NUM>; the controller <NUM> may control the flow the liquid <NUM> to the separator <NUM> utilizing the flow controller <NUM> based on at least the determined indicator value of the freeze point suppressant property of the liquid <NUM>. In some embodiments, the controller <NUM> may include one or more processors. The controller <NUM> may be coupled with the first sensor <NUM> and flow controller <NUM> such that it may receive and/or send signals in a variety of configurations, such as through a physical connection or a wireless connection. While the flow controller <NUM> may be shown such that is positioned between the sensor <NUM> and the separator <NUM>, it may be positioned elsewhere in system <NUM>, such as between separator <NUM> and sensor <NUM> or as part of separator <NUM>, such as to control flows associated with separator <NUM>.

Some embodiments of the system <NUM> include a second sensor <NUM> positioned to determine an indicator value of a freeze point suppressant property of a concentrated freeze point suppressant <NUM>; the second sensor <NUM> may be coupled with the controller <NUM>. In some embodiments, the first sensor <NUM> includes a temperature sensor and the second sensor <NUM> includes a temperature sensor. In some embodiments, the first sensor <NUM> includes a spectrometer and the second sensor <NUM> includes a refractometer. In some embodiments, the first sensor <NUM> includes a temperature sensor and the second sensor <NUM> includes a refractometer. Some embodiments may utilize sensors for the first sensor <NUM> and/or the second sensor <NUM> that may include combinations or permutations of sensors configured to determine or facilitate determining temperature, spectrum, refractive index, density, concentration, conductivity, capacitance, pressure, heat capacity, freezing point, and/or boiling point, for example.

Some embodiments of the system <NUM> include a pump configured to deliver the liquid <NUM> to at least the first sensor <NUM> or the flow controller <NUM>. The liquid <NUM> may also be referred to as a dilute freeze point suppressant. Some embodiments include the separator <NUM> configured to form the concentrated freeze point suppressant <NUM> from the liquid <NUM>. In some embodiments, the separator <NUM> includes at least a thermal separator or a mechanical separator. In some embodiments, the separator <NUM> includes a distillation vessel; for example, the separator <NUM> may include a distillation column. Some embodiments may utilize separators such as an opened kettle boiler, a recirculating plate boiler and separator, and/or a random-packed distillation column.

Separator <NUM> may utilize a wide variety of separation tools and techniques including, but not limited to: reverse osmosis, nano-filtration, photonic-driven precipitation, precipitation by chemical reaction, precipitation by solubility change, surfactant absorption, ion exchange, activated carbon absorption, flash separation, distillation, multi-effect distillation, vapor compression distillation, evaporation, membrane distillation, and/or gas permeable membrane separation. Some embodiments include a mixing tank configured to combine the concentrated freeze point suppressant <NUM> with a solid to form a portion of the liquid <NUM>.

In some embodiments, the controller <NUM> is further configured to utilize the determined indicator value of freeze point suppressant property of the liquid <NUM> to determine a target property value of the concentrated freeze point suppressant <NUM>. In some embodiments, the controller <NUM> is further configured to control the flow of the liquid <NUM> to the separator <NUM> utilizing the flow controller <NUM> based on at least the determined indicator value of the freeze point suppressant property of the concentrated freeze point suppressant <NUM> and/or the determined target property value of the concentrated freeze point suppressant <NUM>.

In some embodiments of system <NUM>, the indicator value of the freeze point suppressant property of the liquid <NUM> includes at least a concentration value of the liquid, a density value of the liquid, a conductivity value of the liquid, a capacitance value of the liquid, a refractive index value of the liquid, a temperature value of the liquid, a pressure value of the liquid, a heat capacity value of the liquid, a freezing point value of the liquid, or a boiling point value of the liquid. In some embodiments, the target property value of the concentrated freeze point suppressant <NUM> includes at least a concentration value of the concentrated freeze point suppressant, a density value of the concentrated freeze point suppressant, a conductivity value of the concentrated freeze point suppressant, a capacitance value of the concentrated freeze point suppressant, a refractive index value of the concentrated freeze point suppressant, a temperature value of the concentrated freeze point suppressant, a pressure value of the concentrated freeze point suppressant, a heat capacity value of the concentrated freeze point suppressant, a freezing point value of the concentrated freeze point suppressant, or a boiling point value of the concentrated freeze point suppressant. In some embodiments, the indicator value of the freeze point suppressant property of the concentrated freeze point suppressant <NUM> includes at least a concentration value of the concentrated freeze point suppressant, a density value of the concentrated freeze point suppressant, a conductivity value of the concentrated freeze point suppressant, a capacitance value of the concentrated freeze point suppressant, a refractive index value of the concentrated freeze point suppressant, a temperature value of the concentrated freeze point suppressant, a pressure value of the concentrated freeze point suppressant, a heat capacity value of the concentrated freeze point suppressant, a freezing point value of the concentrated freeze point suppressant, or a boiling point value of the concentrated freeze point suppressant. Some embodiments may utilize other indicators values with respect to these properties.

In general, the freeze point suppressant may include, but is not limited to, water, alcohol, ionic liquids, amines, ammonia, salt, non-salt soluble solids, organic liquid, inorganic liquid, triethylamine, cyclohexopuridine, mixtures of miscible materials, and/or a surfactant-stabilized mixture of immiscible materials. The melted solid may be formed from a solid that may include a fully or partially solid form of the following, but is not limited to, water, an organic material, an ionic liquid, an inorganic material, and/or DMSO.

One skilled in the art will recognize that this embodiment may represent a simple embodiment of the control architecture. The addition of multiple types of sensors, duplicate sensors, and/or duplicate methods of modulating the flow may result in better overall performance in accordance with various embodiments. Furthermore, the embodiments provided generally show how the control architecture may operate with different types of sensors and different types of separation equipment. Thus, the embodiments are not limited to a system with just one type of separation equipment or one type of sensor.

<FIG> shows a system <NUM>-a in accordance with various embodiments. System <NUM>-a of <FIG> may be an example of system <NUM> of <FIG>. A mixing vessel <NUM> may hold a solid <NUM> and a liquid <NUM>, which may be a mixture of the melted solid and a freeze point suppressant. The liquid <NUM> may be extracted from the mixing vessel <NUM>, which may be referred to as a tank in general, by a pump <NUM> as a dilute mixture <NUM>-a (which may be referred to as a liquid in general or a dilute freeze point suppressant). The pump <NUM> may create the flow of liquid <NUM>-a based on an electronic signal <NUM> from the controller <NUM>-a. If liquid <NUM>-a may be flowing in this line, it may flow through a sensor <NUM>-a, which may be responsible for reporting an indicator value of a freeze point property of the liquid <NUM>-a to the controller <NUM>-a. This indicator value may be sent via an electronic signal <NUM>, which may be a wired or wireless signal. The liquid <NUM>-a may then flow to a separation system <NUM>, where it may interact with a flow controller <NUM>-a that may dictate its flow under control of the controller <NUM>-a via an electronic signal <NUM>; while flow controller <NUM>-a may be shown as part of separation system <NUM>, it may be separate from separation system <NUM> in some embodiments. At this dictated flow, the separation system <NUM> may be able to appropriately separate, with separator <NUM>-a, the mixture <NUM>-a into pure or higher purity liquid <NUM>, which may be re-solidified into the solid <NUM> in some embodiments, and concentrated freeze point suppressant <NUM>-a, which may flow out of the separation system <NUM> into a second sensor <NUM>-a, which may report an indicator value of a freeze point property of the concentrated freeze point suppressant <NUM>-a to the controller <NUM>-a via an electronic signal <NUM>. In some embodiments, liquid <NUM> may be a diluted freeze point suppressant. After passing through the high concentration side sensor <NUM>-a, the concentrated freeze point suppressant <NUM>-a may flow back to the tank <NUM>. In general, the electronic signals <NUM>, <NUM>, <NUM>, and/or <NUM> may include wired or wireless signals.

<FIG> shows a system <NUM>-b that may be a specific embodiment of a freeze point suppression control architecture that may involve a single speed pump <NUM>-a, two temperature sensors <NUM>-b, <NUM>-b, and a control valve <NUM>-b. System <NUM>-b of <FIG> may be an example of system <NUM> of <FIG> or system <NUM>-a of <FIG>. A mixing vessel <NUM>-a may hold a solid <NUM>-a and a liquid <NUM>-a that may be a mixture of the melted solid and a freeze point suppressant. The liquid <NUM>-a may be extracted from the mixing vessel <NUM>-a, which may also be referred to as a tank, by a single speed pump <NUM>-a as a dilute mixture <NUM><NUM>-b, which may be referred to as a liquid. The pump <NUM>-a may create a flow of liquid <NUM><NUM>-b, which may also be considered liquid <NUM>-a, based on an electronic signal <NUM>-a from a controller <NUM>-b. If liquid may be flowing in this line, it may flow through a temperature sensor <NUM>-b, which may be responsible for reporting the temperature of the liquid <NUM>-b to the controller <NUM>-b. This indicator value of a freeze point suppressant property of the liquid <NUM>-b may be sent via an electronic signal <NUM>-a. The fluid <NUM>-b may then flow to a separation system <NUM>-a, where it may interact with a control valve <NUM>-b, which may dictate its flow under control of the controller <NUM>-b via an electronic signal <NUM>-a. At this dictated flow, the separation system <NUM>-a, which in this embodiment may include a distillation vessel <NUM>-b, may be able to appropriately separate the mixture into pure or higher purity liquid <NUM>-a, which may be re-solidified into the solid <NUM>-a in some embodiments, and concentrated freeze point suppressant <NUM>-b; in some embodiments, liquid <NUM>-a may include a diluted freeze point suppressant. The concentrated freeze point suppressant <NUM>-b may flow out of the distillation vessel <NUM>-b into a second temperature sensor <NUM>-b, which may report a temperature to the controller <NUM>-b via an electronic signal <NUM>-a; this temperature may be an indicator value of a freeze point suppressant property of the concentrated freeze point suppressant <NUM>-b. After passing through the high concentration side sensor <NUM>-b, the concentrated freeze point suppressant <NUM>-b may flow back to the tank <NUM>-a.

<FIG> shows control logic <NUM> that may be used by the control architecture in order to control the freeze point suppression cycle for different embodiments, such as system <NUM>-b of <FIG>. For example, if implemented with respect to system <NUM>-b of <FIG>, temperature sensor <NUM>-b may report a temperature value to the controller <NUM>-b via electronic signal <NUM>-a. The temperature signal received may be used to decide if the pump <NUM>-a should be running. This decision may result in electronic signal <NUM>-a being sent to the pump <NUM>-a. The temperature signal may also be interpreted by the controller <NUM>-b via a property based algorithm <NUM> that may return a concentration value <NUM>. This concentration value <NUM> may then be fed into a second property based algorithm <NUM>, which may return target information <NUM> to a main proportional integration differential control loop <NUM>. This loop may utilize feedback control from the second temperature sensor <NUM>-b, which may be sent via electronic signal <NUM>-a and may be interpreted through a property based algorithm <NUM>. The result of this control loop may be electronic signal <NUM>-a sent to the control valve <NUM>-b that may modulate the flow of dilute freeze point suppressant into the distillation vessel and may maintain proper operation of that equipment in order to achieve the target concentration at the inlet to the mixing vessel.

<FIG> shows a system <NUM>-c for a freeze point suppression control architecture that may involve a variable speed pump <NUM>-b, a spectrometer <NUM>-c, a refractometer <NUM>-c, and controller <NUM>-c. System <NUM>-c of <FIG> may be an example of system <NUM> of <FIG> and/or system <NUM>-a of <FIG>. A mixing vessel <NUM>-b, which may also be referred to as a tank, may holds a solid <NUM>-b and a liquid <NUM>-b, that may be a mixture of the melted solid and a freeze point suppressant. The liquid <NUM>-b can be extracted from the tank <NUM>-b by the variable speed pump <NUM>-b as a dilute mixture <NUM><NUM>-c, which may be referred to as a liquid. The pump <NUM>-b may create or may not create the flow of liquid <NUM>-b based on an electronic signal <NUM>-b from the controller <NUM>-c, but this signal <NUM>-b may not necessarily set the pump's speed. If liquid <NUM>-c may be flowing in this line, it may flow through a spectrometer sensor <NUM>-c, which may be responsible for reporting the spectral signature of the liquid <NUM>-c to the controller <NUM>-c. This indicator value may be sent via an electronic signal <NUM>-b. The liquid <NUM>-c may then flow to a separation system <NUM>-b, where its flow rate may be dictated by a motor speed controller <NUM><NUM>-c, which may send an electronic signal <NUM> to the variable speed motor of pump <NUM>-b and may set the flow rate of liquid <NUM>-c through the separation system <NUM>-b. At this flow control, the separation system <NUM>-b, which in this embodiment may include a distillation vessel <NUM>-c, may be able to appropriately separate the mixture into pure or higher purity liquid <NUM>-b, which may be re-solidified into the solid <NUM>-b in some embodiments, and concentrated freeze point suppressant <NUM>-c; in some embodiments, liquid <NUM>-b is a diluted freeze point suppressant. The concentrated freeze point suppressant <NUM>-c may flow out of the distillation vessel <NUM>-c into a refractometer <NUM>-c, which may report the refractive index to the controller <NUM>-c via an electronic signal <NUM>-b. After passing through the high concentration side sensor <NUM>-c, the concentrated freeze point suppressant <NUM>-c may flow back to the tank <NUM>-b.

<FIG> shows control logic <NUM>-a that may be used by the control architecture in order to control the freeze point suppression cycle for different embodiments, such as system <NUM>-c of <FIG>. For example, if implemented with respect to system <NUM>-c of <FIG>, spectrometer <NUM>-c may report a spectral signal to the controller <NUM>-c via electronic signal <NUM>-b. The spectral signal received may be interpreted via a property based algorithm <NUM>-a and may produce a concentration value <NUM>-a. This concentration value <NUM>-a may be used by another property based algorithm <NUM> to determine a temperature of the mixing vessel and if the pump <NUM>-b should be turned on or off. This decision may be captured in the electronic signal <NUM>-b and may be sent to the pump <NUM>-b. Additionally, this concentration value <NUM>-a may then be fed into a second property based algorithm <NUM>-a that may return target information <NUM>-a to the main proportional integration differential control loop <NUM>-a. This loop <NUM>-a may involve feedback control from the refractometer sensor <NUM>-c, which may be sent via electronic signal <NUM>-b and interpreted through a property based algorithm <NUM>-a. The result of this control loop <NUM>-a may include electronic signal <NUM>-b being sent to the speed controller <NUM>-c, which may modulate the flow of dilute freeze point suppressant into the distillation vessel via the variable speed pump <NUM>-b and may maintain proper operation of that equipment in order to achieve the target concentration at the inlet to the mixing vessel.

<FIG> shows an embodiment of a system <NUM>-d for a freeze point suppression control architecture that may involve a single speed pump <NUM>-c, a temperature sensor <NUM>-d, a refractometer <NUM>-d, and a control valve <NUM>-d. System <NUM>-d of <FIG> may be an example of system <NUM> of <FIG> and/or system <NUM>-a of <FIG>. A mixing vessel <NUM>-c, which may be referred to as a tank, may hold a solid <NUM>-c and a liquid <NUM>-c, which may be a mixture of the melted solid and a freeze point suppressant. The liquid <NUM>-c may be extracted from the tank <NUM>-c by the single speed pump <NUM>-c as a dilute mixture <NUM>-d, which may be a portion of the liquid <NUM>-c. The pump <NUM>-c may create the flow of liquid <NUM>-d based on an electronic signal <NUM>-c from the controller <NUM>-d. If liquid <NUM>-d is flowing in this line, it may flow through a temperature sensor <NUM>-d, which may be responsible for reporting the temperature of the liquid <NUM>-d to the controller <NUM>-d. This indicator value may be sent via an electronic signal <NUM>-c. The liquid <NUM>-d may then flow to a separation system <NUM>-c. Before interacting with the control valve <NUM>-d, the liquid <NUM>-d may first pass through a reverse osmosis membrane <NUM>-d, where, at an elevated pressure, it may separate into an appropriately concentrated freeze point suppressant <NUM>-d and a pure or higher purity liquid <NUM>-c, which may be refrozen to form the solid <NUM>-c in some embodiments; liquid <NUM>-c may include a diluted freeze point suppressant in some embodiments. The pressure may be maintained by the control valve <NUM>-d, which may be controlled by an electronic signal <NUM>-c. The appropriately concentrated freeze point suppressant <NUM>-d may then flow back to the mixing vessel <NUM>-c, while passing through a refractometer <NUM>-d, which may report its refractive index via an electronic signal <NUM>-c to the controller <NUM>-d.

<FIG> shows control logic <NUM>-b that may be used by the control architecture in order to control the freeze point suppression cycle for different embodiments, such as system <NUM>-d of <FIG>. For example, if implemented with respect to system <NUM>-d of <FIG>, temperature sensor <NUM>-d may report a temperature value to the controller <NUM>-d via electronic signal <NUM>-c. The temperature signal received may be used to decide if the pump <NUM>-c should be running. This decision may result in electronic signal <NUM>-c being sent to the pump <NUM>-c. The temperature signal may also be interpreted by the controller <NUM>-d via a property based algorithm <NUM>-b, which may return a concentration value <NUM>-b. This concentration value <NUM>-b can then be fed into a second property based algorithm <NUM>-b, which may return target information <NUM>-b to the main proportional integration differential control loop <NUM>-b. This loop <NUM>-b may involve feedback control from the refractometer <NUM>-d, which may be sent via electronic signal <NUM>-c and may be interpreted through a property based algorithm <NUM>-b. The result of this control loop <NUM>-b may include electronic signal <NUM>-c, which may be sent to the control valve <NUM>-d, which may modulate the flow of dilute freeze point suppressant into the reverse osmosis filters and may maintain proper operation of that equipment in order to achieve the target concentration at the inlet to the mixing vessel.

<FIG> shows a system <NUM>-e in accordance with various embodiments for a freeze point suppression control architecture that may involve a single speed pump <NUM>-d, two temperature sensors <NUM>-e, <NUM>-e, and a variable speed compressor <NUM>-e. System <NUM>-e of <FIG> may be an example of system <NUM> of <FIG> and/or system <NUM>-a of <FIG>. A mixing vessel <NUM>-d, which may be referred to as a tank, may hold a solid <NUM>-d and a liquid <NUM>-d, which may be a mixture of the melted solid and a freeze point suppressant. The liquid <NUM>-d may be extracted from the tank <NUM>-d by a single speed pump <NUM>-d as a dilute mixture <NUM><NUM>-e, which may be a portion of liquid <NUM>-d. The pump <NUM>-d may create the flow of liquid <NUM>-e based on an electronic signal <NUM>-d from the controller <NUM>-e. If liquid <NUM>-e may be flowing in this line, it may flow through the temperature sensor <NUM>-e, which may be responsible for reporting the temperature of the liquid <NUM>-e to the controller <NUM>-e. This indicator value may be sent via an electronic signal <NUM>-d. The fluid <NUM>-e may then flow to a separation system <NUM>-d, where it may enter a distillation vessel <NUM>-e through suction created by the variable speed compressor <NUM>-e, which may act as a flow controller, that may be controlled via electronic signal <NUM>-d from the controller <NUM>-e. At this dictated flow, the separation system <NUM>-d, which in this embodiment may include the distillation vessel <NUM>-e, may be able to appropriately separate the mixture into pure or higher purity liquid <NUM>-d, which may be re-solidified into the solid <NUM>-d in some embodiments, and concentrated freeze point suppressant <NUM>-e; liquid <NUM>-d may include a diluted freeze point suppressant in some embodiments. The concentrated freeze point suppressant <NUM>-e may flow through a second pass inside the distillation vessel <NUM>-e and through the second temperature sensor <NUM>-e, which may report another temperature to the controller <NUM>-e via electronic signal <NUM>-d; a control valve <NUM>-f may facilitate the flow of concentrated freeze point suppressant <NUM>-e. After passing through the high concentration side sensor <NUM>-e, the concentrated freeze point suppressant <NUM>-e may flow back to the tank <NUM>-d.

<FIG> shows a variation of the system <NUM>-e of <FIG> as system <NUM>-e-<NUM>, providing another specific embodiment of a freeze point suppressant control architecture that may involve the single speed pump <NUM>-d, the two temperature sensors <NUM>-e, <NUM>-e, and a variable speed compressor <NUM>-e-<NUM>. The mixing vessel <NUM>-d may hold the solid <NUM>-d and the liquid <NUM>-d that may be a mixture of the melted solid and a freeze point suppressant. The liquid can be extracted from the tank <NUM>-d by the single speed pump <NUM>-d as the dilute mixture <NUM><NUM>-d. The pump <NUM>-d may create the flow of liquid based on electronic signal <NUM>-d from the controller <NUM>-e. If liquid is flowing in this line, it may flow through the temperature sensor <NUM>-e, which may be responsible for reporting the temperature of the liquid to the controller <NUM>-e. This indicator value may be sent via electronic signal <NUM>-d. The fluid then may flow to a separation system <NUM>-d-<NUM> where it may enter a distillation vessel <NUM>-e-<NUM> based on suction created by a variable speed compressor <NUM>-e-<NUM> that may be controlled via electrical signal <NUM>-d-<NUM> from the controller <NUM>-e. At this dictated flow the separation system, which in this embodiment takes the form of a distillation vessel, may be able to appropriately separate the mixture into pure liquid <NUM>-d-<NUM> that may be re-solidified into the solid <NUM>-d and concentrated freeze point suppressant <NUM>-e-<NUM>. The concentrated freeze point suppressant <NUM>-e-<NUM> may flow through the second temperature sensor <NUM>-e, which may report another temperature to the controller <NUM>-e via electronic signal <NUM>-d. After passing through the high concentration side sensor <NUM>-e, the concentrated freeze point suppressant <NUM>-e-<NUM> may flow back to the tank <NUM>-d. The variable speed compressor <NUM>-e-<NUM> may create a flow that passes through the distillation vessel <NUM>-e-<NUM> in a second pass. This may form a pure liquid <NUM>-d-<NUM> flow out of this pass that flows through a control valve <NUM>-f-<NUM>.

<FIG> shows control logic <NUM>-c that may be used by the control architecture in order to control the freeze point suppression cycle for different embodiments, such as system <NUM>-e of <FIG> and/or system <NUM>-e-<NUM> of <FIG>. For example, if implemented with respect to system <NUM>-e of <FIG> or system <NUM>-e-<NUM> of <FIG>, temperature sensor <NUM>-e may report a temperature value to the controller <NUM>-e via an electronic signal <NUM>-d. The temperature signal received may be used to decide if the pump <NUM>-d should be running. This decision may result in electronic signal <NUM>-d being sent to the pump <NUM>-d. The temperature signal may also be interpreted by the controller <NUM>-e via a property based algorithm <NUM>-c, which may return a concentration value <NUM>-c. This concentration value <NUM>-c may then be fed into a second property based algorithm <NUM>-c, which may return target information <NUM>-c to a main proportional integration differential control loop <NUM>-c. This loop <NUM>-c may include feedback control from the second temperature sensor <NUM>-e, which may be sent via an electronic signal <NUM>-d and may be interpreted through a property based algorithm <NUM>-c. The result of this control loop <NUM>-c may include electronic signal <NUM>-d (or <NUM>-d-<NUM> for system <NUM>-e-<NUM>) being sent to the variable speed compressor <NUM>-e (or <NUM>-e-<NUM> for system <NUM>-e-<NUM>), which may modulate the flow of dilute freeze point suppressant into the distillation vessel <NUM>-e (or <NUM>-e-<NUM> for system <NUM>-e-<NUM>) and may maintain proper operation of that equipment in order to achieve the target concentration at the inlet to the mixing vessel. Electronic signal <NUM>-d (or <NUM>-d-<NUM>) may also sent to control valve <NUM>-f (or <NUM>-f-<NUM>).

These embodiments generally show the consistent application of the control hardware and software across multiple sensor types and multiple separation technologies. Regardless of the sensor type of separation technology, the control logic and hardware integration strategy may be applied to maintain the property concentration and temperature inside the mixing vessel and perform useful refrigeration at a temperature below the freezing point of the solid.

Turning now to <FIG>, <FIG>, <FIG>, and <FIG>, examples of property algorithm graphs are provided in accordance with various embodiments that are generally related to <FIG>, <FIG>, <FIG>, and/or <FIG>. For example, <FIG> shows a graph <NUM> that may relate a freeze point with a concentration; this graph may represent the property algorithms <NUM> of <FIG>, <NUM>-b of <FIG>, and/or <NUM>-c of <FIG>. Graph <NUM> may relate concentration with saturation point; this graph may represent the property algorithms <NUM> of <FIG>, <NUM> of <FIG>, <NUM>-c of <FIG>, and/or <NUM>-c of <FIG>. <FIG> shows a graph <NUM> that may relate transmittance with wavelength; this graph may represent the property algorithm <NUM>-a of <FIG>. Graph <NUM> may relate concentration with saturation point; this graph may represent the property algorithm <NUM>-a of <FIG>. <FIG> shows a graph <NUM> that may relate concentration with freeze point; this graph may represent the property algorithm <NUM>-b of <FIG>. Graph <NUM> may relate refractive index with concentration; this graph may represent the property algorithm <NUM>-a of <FIG> and/or <NUM>-b of <FIG>. <FIG> shows a graph <NUM> that may relate concentration with osmotic pressure; this graph may represent the property algorithm <NUM>-b of <FIG>. Graphs <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> merely provide examples of the property algorithms that may be utilized in various embodiments; some embodiments may utilize different property algorithms.

Turning now to <FIG>, a flow diagram of a method <NUM> is shown in accordance with various embodiments. Method <NUM> may be implemented utilizing a variety of systems, control logics, and/or devices such as those shown and/or described with respect to <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, and/or <FIG>. The method <NUM> may be referred to as a method of freeze point suppression cycle control.

At block <NUM>, a liquid may flow to a first sensor; the liquid may include a mixture of a melted solid and a freeze point suppressant. At block <NUM>, an indicator value of a freeze point suppressant property of the liquid may be determined utilizing the first sensor. At block <NUM>, a flow of the liquid to a separator may be controlled utilizing a flow controller based on at least the determined indicator value of the freeze point suppressant property of the liquid; the separator may form a concentrated freeze point suppressant from the liquid. In some embodiments, the separator may form the concentrated freeze point suppressant from the liquid by separating at least a portion of the freeze point suppressant from the liquid; this may also form a dilute freeze point suppressant. In some embodiments, the separator may form the concentrated freeze point suppressant from the liquid through separating at least a portion of the melted solid from the liquid; this may form a pure or higher purity melted solid in some embodiments.

In some embodiments, the method <NUM> may include: determining a target property value of the concentrated freeze point suppressant based on the determined indicator value of the freeze point suppressant property of the liquid; determining an indicator value of a freeze point suppressant property of the concentrated freeze point suppressant utilizing a second sensor; and/or controlling further the flow of the liquid to the separator utilizing the flow controller based on at least the determined indicator value of the freeze point suppressant property of the concentrated freeze point suppressant and the determined target property value of the concentrated freeze point suppressant.

In some embodiments of method <NUM>, determining the indicator value of the freeze point suppressant property of the liquid includes determining a temperature value of the liquid utilizing the first sensor and determining the indicator value of the freeze point suppressant property of the concentrated freeze point suppressant includes determining a temperature value of the concentrated freeze point suppressant utilizing the second sensor; the first sensor may include a temperature sensor and the second sensor may include a temperature sensor. In some embodiments, determining the indicator value of the freeze point suppressant property of the liquid includes determining a spectral signature of the liquid utilizing the first sensor and determining the indicator value of the freeze point suppressant property of the concentrated freeze point suppressant includes determining a refractive index of the concentrated freeze point suppressant utilizing the second sensor; the first sensor may include a spectrometer and the second sensor may include a refractometer. In some embodiments, determining the indicator value of the freeze point suppressant property of the liquid includes determining a temperature of the liquid utilizing the first sensor and determining the indicator value of the freeze point suppressant property of the concentrated freeze point suppressant includes determining a refractive index of the concentrated freeze point suppressant utilizing the second sensor; the first sensor may include a temperature sensor and the second sensor may include a refractometer.

Some embodiments of method <NUM> may utilize sensors for the first sensor and the second sensor that may include combinations or permutations of sensors configured to determine or facilitate determining temperature, spectrum, refractive index, density, concentration, conductivity, capacitance, pressure, heat capacity, freezing point, or boiling point, for example.

Some embodiments of method <NUM> include pumping the liquid from a tank to the first sensor; the liquid may be formed in the tank through combining the freeze point suppressant and a solid that forms the melted solid. Some embodiments include forming the concentrated freeze point suppressant from the liquid utilizing the separator. Some embodiments include combining the concentrated freeze point suppressant with a solid to form a portion of the liquid.

In some embodiments, the separator includes a distillation vessel; for example, some embodiments may utilize a distillation column. The separator may include at least a mechanical separator or a thermal separator. Some embodiments may utilize separators such as an opened kettle boiler, a recirculating plate boiler and separator, and/or a random-packed distribution column.

A wide variety of separation techniques may be utilized with method <NUM>, including, but are not limited to: reverse osmosis, nano-filtration, photonic driven precipitation, precipitation by chemical reaction, precipitation by solubility change, surfactant absorption, ion exchange, activated carbon absorption, flash separation, distillation, multi-effect distillation, vapor compression distillation, evaporation, membrane distillation, and/or gas permeable membrane separation.

In some embodiments of method <NUM>, the indicator value of the freeze point suppressant property of the liquid includes at least a concentration value of the liquid, a density value of the liquid, a conductivity value of the liquid, a capacitance value of the liquid, a refractive index value of the liquid, a temperature value of the liquid, a pressure value of the liquid, a heat capacity value of the liquid, a freezing point value of the liquid, or a boiling point value of the liquid. In some embodiments, the target property value of the concentrated freeze point suppressant includes least a concentration value of the concentrated freeze point suppressant, a density value of the concentrated freeze point suppressant, a conductivity value of the concentrated freeze point suppressant, a capacitance value of the concentrated freeze point suppressant, a refractive index value of the concentrated freeze point suppressant, a temperature value of the concentrated freeze point suppressant, a pressure value of the concentrated freeze point suppressant, a heat capacity value of the concentrated freeze point suppressant, a freezing point value of the concentrated freeze point suppressant, or a boiling point value of the concentrated freeze point suppressant. In some embodiments, the indicator value of the freeze point suppressant property of the concentrated freeze point suppressant includes at least a concentration value of the concentrated freeze point suppressant, a density value of the concentrated freeze point suppressant, a conductivity value of the concentrated freeze point suppressant, a capacitance value of the concentrated freeze point suppressant, a refractive index value of the concentrated freeze point suppressant, a temperature value of the concentrated freeze point suppressant, a pressure value of the concentrated freeze point suppressant, a heat capacity value of the concentrated freeze point suppressant, a freezing point value of the concentrated freeze point suppressant, or a boiling point value of the concentrated freeze point suppressant.

In some embodiments of method <NUM>, forming the concentrated freeze point suppressant from the liquid utilizing the separator includes at least separating at least a portion of the freeze point suppressant from the liquid or separating at least a portion of the melted solid from the liquid. In some embodiments, the flow controller includes a variable-speed compressor that creates suction with respect to the distillation vessel. Some embodiments include flowing the concentrated freeze point suppressant through a control valve coupled with the controller that control at least a flow of the concentrated freeze point suppressant from the distillation vessel or a flow of liquid from the distillation vessel to reform the melted solid.

Turning now to <FIG>, a flow diagram of a method <NUM>-a is shown in accordance with various embodiments. Method <NUM>-a may be implemented utilizing a variety of systems, control logics, and/or devices such as those shown and/or described with respect to <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, and/or <FIG>. System <NUM>-a may be an example of method <NUM> of <FIG>.

At block <NUM>-a, a liquid may flow to a first sensor where the liquid includes a mixture of a melted solid and a freeze point suppressant. At block <NUM>-a, an indicator value of a freeze point suppressant property of a liquid may be determined utilizing the first sensor. At block <NUM>, a target property value of a concentrated freeze point suppressant may be determined based on the determined indicator value of the freeze point suppressant property of the liquid. At block <NUM>, an indicator value of a freeze point suppressant property of the concentrated freeze point suppressant may be determined utilizing a second sensor. At block <NUM>-a, the flow of the liquid to a separator may be controlled utilizing a flow controller based on at least the determined indicator value of the freeze point suppressant property of the concentrated freeze point suppressant and the determined target property value of the concentrated freeze point suppressant.

These embodiments may not capture the full extent of combination and permutations of materials and process equipment. However, they may demonstrate the range of applicability of the method, devices, and/or systems. The different embodiments may utilize more or fewer stages than those described.

It should be noted that the methods, systems, and devices discussed above are intended merely to be examples. It must be stressed that various embodiments may omit, substitute, and/or add various procedures or components as appropriate. For instance, it should be appreciated that, in alternative embodiments, the methods may be performed in an order different from that described, and that various stages may be added, omitted, or combined. Also, features described with respect to certain embodiments may be combined in various other embodiments. Different aspects and elements of the embodiments may be combined in a similar manner. Also, it should be emphasized that technology evolves and, thus, many of the elements are exemplary in nature and should not be interpreted to limit the scope of the embodiments.

Specific details are given in the description to provide a thorough understanding of the embodiments. However, it will be understood by one of ordinary skill in the art that the embodiments may be practiced without these specific details. For example, well-known circuits, processes, algorithms, structures, and techniques have been shown without unnecessary detail in order to avoid obscuring the embodiments.

Also, it is noted that the embodiments may be described as a process which may be depicted as a flow diagram or block diagram or as stages. Although each may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be rearranged. A process may have additional stages not included in the figure.

Claim 1:
A method of freeze point suppression cycle control comprising:
forming a liquid in a tank through combining a freeze point suppressant and a solid, wherein the freeze point suppressant melts the solid to form the liquid;
pumping the liquid from the tank to a first sensor wherein the liquid includes a mixture of the melted solid and the freeze point suppressant;
determining (<NUM>) an indicator value of a freeze point suppressant property of the liquid utilizing the first sensor;
controlling (<NUM>) a flow of the liquid to a separator utilizing a flow controller based on at least the determined indicator value of the freeze point suppressant property of the liquid, wherein the separator forms a concentrated freeze point suppressant from the liquid;
forming a concentrated freeze point suppressant from the liquid utilizing the separator;
determining an indicator value of a freeze point suppressant property of the concentrated freeze point suppressant utilizing a second sensor;
controlling further the flow of the liquid to the separator utilizing the flow controller based on at least the determined indicator value of the freeze point suppressant property of the concentrated freeze point suppressant
flowing the concentrated freeze point suppressant from the separator to the tank.