System and method for wastewater heat recovery

Abstract

Described herein are systems and methods for waste water heat recovery, including a system for heat recovery, the system comprising: (i) a heat exchanger configured to heat water using heat energy recovered from a waste water stream, where the waste water stream is treated by a waste water treatment system in fluid communication with the heat recovery system; and (ii) a device configured to control a flow rate of wastewater in the heat recovery system based at least in part on the real-time sensor data.

Description

[0001] Cross-references

[0002] This application claims priority to U.S. Provisional Application No. 63 / 371,698, filed on August 17, 2022, the contents of which are incorporated herein in their entirety. Background Art

[0003] The use of hot water in buildings (including hot water used for showers, toilets, laundry, etc.) increases the temperature of the wastewater stream. This hot water is a valuable heat source for other uses in the building. The heat recovery module converts the heat in the wastewater into usable heat for applications such as preheating water in a boiler or hot water tank. Current heat recovery technology can use a heat pump. Heat pump technology uses electricity and a reverse refrigeration cycle to transfer heat from one place to another. However, heat pumps can be expensive, requiring high capital costs and complex settings. An alternative is a heat exchanger, which is a passive technology that does not require any external energy. The heat exchanger promotes the transfer of internal heat energy between two fluids without mixing the two. The heat exchanger can be used to transfer heat energy from the wastewater stream to another source, such as a building hot water supply. The heat exchanger requires the wastewater to have a sufficiently high temperature to heat the building water loop. However, the current heat exchanger system may have poor heat recovery performance when integrated with the wastewater treatment system. For example, although untreated wastewater has the highest amount of heat energy before treatment, poor water quality and the presence of impurities may lead to high operating costs. Treated water is of higher quality, but heat energy is lost during its transport through the wastewater treatment system, resulting in low heat recovery performance. Summary of the invention

[0004] There is a need for a heat recovery system that reduces costs without significantly compromising heat recovery performance. In addition, there is a need for a heat recovery system that can be integrated with a new or existing wastewater treatment system in a simple and convenient manner. The present disclosure provides systems and methods for recovering heat and energy present in wastewater. Wastewater, which may have its temperature increased due to the use of hot water throughout a building, provides a valuable but underutilized source of thermal energy. The methods and systems described herein can convert the heat and energy present in wastewater into usable energy. In some cases, the recovered energy can be used for other purposes within the building, including preheating water for a boiler or hot water tank.

[0005] Various advantages of the embodiments described herein are: they provide efficient, economical on-site wastewater heat recovery for buildings (e.g., commercial and residential buildings, food and industrial processing facilities) or other entities; they capture heat for use in various domestic and industrial processes or to generate hot water for space heating; they generally conserve water and energy; and they are easily integrated.

[0006] An improved wastewater heat recovery system is described herein. In one aspect, a system is provided herein that includes: (i) a heat exchanger configured to heat water using heat energy recovered from a wastewater stream, wherein the wastewater stream is treated by a wastewater treatment system in fluid communication with the heat recovery system; and (ii) an apparatus configured to control a flow rate of wastewater in the heat recovery system based at least in part on real-time sensor data.

[0007] In some embodiments, the wastewater is at least partially treated by a wastewater treatment system before entering the heat recovery system. In some embodiments, the heat exchanger comprises a plate and frame heat exchanger. In some embodiments, the wastewater is treated by a wastewater treatment system after leaving the heat recovery system. In some embodiments, the heat exchanger comprises a shell and tube heat exchanger. In some embodiments, the system further comprises a screening system. In some embodiments, the device is configured to control the flow rate of the wastewater based at least in part on the temperature of the wastewater stream. In some embodiments, the device is configured to increase the flow rate of the wastewater when the temperature of the wastewater stream is above a threshold. In some embodiments, the device is configured to reduce the flow rate of the wastewater when the temperature of the wastewater stream is below a threshold. In some embodiments, the device is configured to control the flow rate of the wastewater based at least in part on the demand for hot water. In some cases, the device is configured to increase the flow rate of the wastewater through the system when the demand for hot water is above a threshold. In some cases, the device is configured to increase the flow rate of the wastewater through the system when the demand for hot water is above a threshold.

[0008] In some embodiments, the system further comprises a wastewater holding tank. In some embodiments, the apparatus is configured to control the flow rate of the wastewater based at least in part on the amount of wastewater present in the wastewater holding tank. In some embodiments, the apparatus is configured to shut down when the amount of wastewater present in the wastewater holding tank is below a threshold level. Alternatively, or in addition, the pump is configured to shut down when the temperature of the wastewater tank is below a predetermined threshold.

[0009] In some embodiments, the heat recovery system is contained in a complete skid mounted system. In some embodiments, the complete skid mounted system is configured to be added to an existing wastewater treatment system. In some embodiments, the system is located at a location within a wastewater source. In some embodiments, the wastewater source is a building, and the system is located in the basement of the building. Alternatively, the system can be located in any suitable place inside or outside the building. In some embodiments, the system is fully automated. In some cases, at least a portion of the wastewater used by the heat recovery system is not completely processed by the wastewater treatment system. In some cases, the device is a pump. In some cases, the device is a valve. In some cases, the wastewater source is a building, and the system is located outside the building. In some cases, the system is located off-site at the wastewater source.

[0010] Incorporation by reference

[0011] All publications, patents, and patent applications mentioned in this specification are incorporated herein by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. If the publications and patents or patent applications incorporated by reference contradict the disclosure contained in the specification, the specification is intended to supersede and / or take precedence over any such contradictory material. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The novel features of the present invention are particularly set forth. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description of illustrative embodiments in which the principles of the present invention are utilized and the accompanying drawings (also referred to herein as "figures"), in which:

[0013] Figure 1 shows an integrated wastewater treatment and heat recovery process according to some embodiments;

[0014] Figure 2 A process flow diagram illustrating an integrated wastewater treatment and heat recovery process according to some embodiments;

[0015] Figure 3 shows a 30,000 gallon per day wastewater treatment system including wastewater heat recovery according to some embodiments;

[0016] Figure 4 shows a 37,000 gallon per day wastewater treatment system including wastewater heat recovery according to some embodiments;

[0017] Figure 5 shows a 50,000 gallon per day wastewater treatment system including wastewater heat recovery according to some embodiments;

[0018] Fig. 6A shows a shell and tube heat exchanger according to some embodiments;

[0019] Figure 6B shows a cross-sectional view of a shell and tube heat exchanger according to some embodiments;

[0020] Figure 7 A plate and frame heat exchanger according to some embodiments is shown. DETAILED DESCRIPTION

[0021] Although various embodiments of the present invention have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many variations, changes and substitutions may occur to those skilled in the art without departing from the present invention. It should be understood that various alternatives to the embodiments of the present invention described herein may be employed.

[0022] The present disclosure provides systems and methods for recovering heat and energy present in wastewater. Wastewater can come from a source such as a building or any other type of structure. In some embodiments, the wastewater source can be a municipal sewer. The building can be a residential building, a commercial building, an industrial building, or any other type of building. The water source can be a high-density building or other structure. The high-density source can have a large number of water-consuming sources. The high-density source can have at least 5, 10, 15, 20, 30, 40, 50, 70, 100 or more water-consuming sources within the structure. Examples of wastewater sources can include, but are not limited to, apartment buildings, townhouses, single-family homes, office buildings, educational facilities, manufacturing facilities, medical facilities, government buildings, stores, or any other type of structure. The wastewater source can be a group of buildings. In some cases, the wastewater source is a campus, a region, or a municipality. In some embodiments, the wastewater source can include a multi-family residential unit, such as an apartment building. In some embodiments, an apartment building can include any number of apartment units. For example, an apartment building may include 10 units, 20 units, 50 units, 100 units, 250 units, 500 units, 750 units, 1000 units, 5000 units, or any other number of units. Examples of water consuming sources may include toilets, sinks, showers, washing machines, dishwashers, cooling towers, and irrigation systems, etc. Wastewater from one or more water consuming sources or one or more wastewater sources may be collected on-site or near the wastewater source.

[0023] In some embodiments, the heat recovery system can use a heat exchanger integrated with an improved control mechanism that can optimize each part of the process and thus reduce operating costs. The temperature of wastewater will usually increase due to the application in which it is used. For example, hot water used for showering, cooking, cleaning, washing clothes, etc. can increase the temperature of the wastewater stream. When the heated wastewater travels through a building and is treated or enters a sewer, the temperature of the stream can be reduced until the temperature reaches the ambient temperature. Therefore, the heat energy in the wastewater stream is lost and cannot be recovered. The systems and methods herein recycle the heat energy stored in the wastewater stream and convert it into a heat source that can be used for various applications with improved performance.

[0024] In some embodiments, the heat recovery system of the present invention can be applied at the wastewater treatment system level. The heat recovery system can be coupled to the wastewater treatment system and can dynamically adapt to the wastewater treatment process to recover heat from treated wastewater, untreated wastewater, or partially treated wastewater within the wastewater treatment system. By avoiding unnecessary treatment of unusable wastewater and collecting the energy of such water for heat recovery, the overall efficiency of heat recovery and wastewater treatment can be improved. In some embodiments, the integrated heat recovery and wastewater treatment system may include an automatic control system configured to perform wastewater transfer timing and recovery extraction, thereby maximizing system uptime and heat recovery capabilities. Details about automatic control will be described later in this article.

[0025] Wastewater treatment and heat recovery system provided herein can be located substantially on site. This beneficially reduces the heat loss due to transportation. In some cases, part of the wastewater treatment and heat recovery system can be located on site, and part can be located at a remote central processing facility. Alternatively, wastewater can be separated into waste solid components and separated water components at or near a wastewater source (e.g., a building). Separation can be performed as a decentralized system. Solid waste can be processed on site or near a wastewater source, and / or can be processed at a remote processing facility. The separated water components can be processed on site or near a wastewater source. Heat recovery can be performed substantially on site. The recovered heat can be used for on-site use.

[0026] Field activities can occur at a location within a wastewater source (e.g., a building). The location can be partially located within the wastewater source. The location can also be physically located outside the wastewater source, but operably connected to the wastewater source so that the location is within the site of the wastewater source or connected to the site of the wastewater source. For example, field activities can be located on the same property of the wastewater source. Field activities can occur below the wastewater source. Field activities can occur underground. In some examples, activities can occur near the site. For example, activities (e.g., wastewater heat recovery) can occur within three blocks, two blocks, one block, one hundred feet, fifty feet, forty feet, thirty feet, twenty feet, or ten feet of the property where the wastewater source (e.g., building) or the wastewater source is located. For example, activities (e.g., wastewater heat recovery) can occur more than one mile away from the wastewater source (e.g., building) or the property where the wastewater source is located.

[0027] In some embodiments, the amount of wastewater flowing through the wastewater heat recovery system is about 5,000 gallons per day to about 1,000,000 gallons per day, as well as any amount below 5,000 gallons per day or above 1,000,000 gallons per day. In some embodiments, the amount of water flowing through the wastewater heat recovery system is about 5,000 gallons per day to about 1,000,000 gallons per day. In some embodiments, the amount of water flowing through the wastewater heat recovery system is about 5,000 gallons per day to about 20,000 gallons per day, about 5,000 gallons per day to about 60,000 gallons per day, about 5,000 gallons per day to about 100,000 gallons per day, about 5,000 gallons per day to about 500,000 gallons per day, about 5,000 gallons per day to about 1,000,000 gallons per day, about 20,000 gallons per day to about 60,000 gallons per day, about 20,000 gallons per day to about 100,000 gallons per day, about 20 ...500,000 gallons per day, about 5,000 gallons per day to about 1,000,000 gallons per day, about 20,000 gallons per day to about day to about 500,000 gallons per day, about 20,000 gallons per day to about 1,000,000 gallons per day, about 60,000 gallons per day to about 100,000 gallons per day, about 60,000 gallons per day to about 500,000 gallons per day, about 60,000 gallons per day to about 1,000,000 gallons per day, about 100,000 gallons per day to about 500,000 gallons per day, about 100,000 gallons per day to about 1,000,000 gallons per day, or about 500,000 gallons per day to about 1,000,000 gallons per day. In some embodiments, the amount of water flowing through the wastewater heat recovery system is about 5,000 gallons per day, about 20,000 gallons per day, about 60,000 gallons per day, about 100,000 gallons per day, about 500,000 gallons per day, or about 1,000,000 gallons per day. In some embodiments, the amount of water flowing through the wastewater heat recovery system is at least about 5,000 gallons per day, about 20,000 gallons per day, about 60,000 gallons per day, about 100,000 gallons per day, or about 500,000 gallons per day. In some embodiments, the amount of water flowing through the wastewater heat recovery system is up to about 20,000 gallons per day, about 60,000 gallons per day, about 100,000 gallons per day, about 500,000 gallons per day, or about 1,000,000 gallons per day.

[0028] Figure 1An example of an integrated wastewater heat recovery and wastewater treatment system is shown. Wastewater can enter through valve 1. In some cases, the valve is a three-way valve. In one direction, wastewater can be directed through an integrated heat recovery and wastewater treatment system. In another direction, wastewater can be directed to a sewer and bypass the wastewater treatment and heat recovery system. The valve can be adjusted manually or automatically. If the wastewater treatment system is undergoing maintenance or an error occurs within the system, the three-way valve can be used to divert wastewater to the sewer. Once the wastewater enters the treatment system, it can flow through a screening unit, such as a microscreen 2. The screening unit (e.g., microscreen 2) can be used to filter and collect solids present in the wastewater.

[0029] Next, the wastewater can enter the pre-treatment tank 3. In some cases, the pre-treatment tank 3 can be equipped with a sensor. In some cases, the sensor can include a temperature sensor for measuring the water temperature in the pre-treatment tank. The temperature sensor can be located at any position of the tank, the inlet / outlet of the tank, etc. In some cases, the sensor can include a sensor for measuring the water level in the pre-treatment tank. In some cases, at least a portion of the water in the pre-treatment tank can be used in a heat recovery system to exchange heat with building water to be heated. In some cases, at least a portion of the water in the pre-treatment tank can be pumped to the heat recovery system. The sensor for measuring the water level can be beneficial to protect the pump. Any suitable sensor can be used to sense the water level. For example, the sensor can be a contact or non-contact device. The non-contact sensor can be an ultrasonic or hydrostatic sensor. Sensor data about the temperature and / or water level in the tank can be processed by a controller of the heat recovery system to control the pump in the heat recovery system, trigger an alarm and / or other actions of the heat recovery system and / or the wastewater treatment system.

[0030] The wastewater from which the solids have been filtered can then flow through a series of treatment and disinfection processes. The wastewater can enter a membrane bioreactor ("MBR") process skid 4. The MBR process can include a membrane process (such as microfiltration or ultrafiltration) combined with a biological wastewater treatment process (activated sludge process).

[0031] Additionally, the wastewater may flow through an aerobic tank 5 and / or an anoxic tank 6 for further treatment. For example, nitrogen and phosphorus removal may be performed by microbial decomposition in the tank. The treated wastewater may then flow to a UV and / or chlorination device for disinfection before flowing into a regeneration water tank 7. In some embodiments, a heat recovery system may be located near the regeneration water tank. The regeneration water tank may also be referred to as a treated water storage tank or holding tank interchangeably throughout the specification.

[0032] The heat recovery system may be in fluid communication with the regeneration water tank 7. In some embodiments, the regeneration water tank 7 may be equipped with a sensor for measuring the temperature or water level or other conditions of the treated wastewater. The temperature sensor and / or water level sensor may be the same as the above-mentioned sensors.

[0033] Wastewater can enter the heat recovery portion of the process through a heat recovery unit (system) 8. The heat recovery unit 8 may include a heat exchanger or a series of heat exchangers. The heat recovery unit 8 can be used to transfer the heat energy present in the treated wastewater to another fluid. In some embodiments, the heat recovery unit 8 may include a pump or valve 9 to control the flow in the heat recovery system. In some cases, a pump or valve can be used to control the treated wastewater flowing into the heat exchanger. In some cases, a pump or a control valve can be used to control the flow of building water to be heated in the heat exchanger. After the wastewater has passed through the heat recovery unit 8, it can be routed back to the regeneration water tank 7 via a pipeline. In some cases, a control valve 801 can be integrated into the pipeline. The control valve 801 can be used to control the flow of wastewater in the heat recovery system.

[0034] Figure 2An example of an integrated wastewater heat recovery and wastewater treatment system is schematically shown. The system can be located on site (e.g., in a building) or outside of a structure. In some embodiments, the integrated heat recovery and wastewater treatment system is located in the basement of a building. Wastewater (including sewage (black water), gray water, or process wastewater) can flow from a building into an integrated wastewater heat recovery and wastewater treatment system. Wastewater can flow into an integrated wastewater heat recovery and wastewater treatment system through a collection pipe of a building. Wastewater from a building can come from sources such as industrial processes, flush toilets (WC or "toilets"), urinals, bathtubs, showers, or sinks. For example, other sources can include dishwashers and washing machines. Due to its use in a building, the temperature of the wastewater can be increased. For example, wastewater can be heated for showering, laundry, or dishwashing. Wastewater containing sewage (black water) can flow from a building through a microscreen or other screening process via one or more pipelines. The microscreen can separate solid waste from black water. Solid waste can be sent to an off-site facility. Then, the remaining wastewater (now without solid waste) can flow to a balanced storage tank. Grey water (wastewater not containing human waste) can flow out of the building via one or more pipes and flow directly to the equalization storage tank, bypassing the screening. In some cases, multiple equalization storage tanks (also referred to as storage tanks) are used. The equalization or storage tank (or multiple equalization or storage tanks) will generally be designed to manage the peak flow of the system to which it is attached. The wastewater flow can flow from the equalization storage or storage tank to the heat recovery system. The heat recovery system may include one or more pumps and heat exchangers. The heat exchanger may be used to promote the transfer of heat from warm wastewater to another water flow. Another water flow may be domestic water. The heated domestic water may leave the heat exchanger and flow to the domestic hot water storage tank or flow directly into the building for use. In some embodiments, the wastewater flow leaves the equalization storage tank and enters the treatment and disinfection process. The treatment and disinfection process may include anoxic process, aerobic process, MBR process, UV disinfection, ozone contact, activated carbon, chlorine disinfection or a combination thereof. The treatment and disinfection process may produce waste activated sludge (WAS). The waste activated sludge may leave the wastewater treatment process and enter the sewer. Treated wastewater can leave the treatment process and undergo reverse osmosis (if necessary). The reverse osmosis process can produce a reverse osmosis concentrate. The reverse osmosis concentrate stream can flow back to the building or into a sewer. Treated wastewater can leave the reverse osmosis process and enter a treated water storage tank. If reverse osmosis is not required, treated wastewater can flow directly from the treatment and disinfection process to the treated water storage tank. If necessary, the treated water storage tank can also be filled with municipal water. Treated wastewater can be reused on-site or off-site. In some cases, the treated wastewater stream can flow to a heat recovery system. The heat recovery system can include one or more pumps and a heat exchanger. The heat exchanger can be used to facilitate heat transfer from treated wastewater to another water stream. Another water stream can be domestic water.The heated domestic water can leave the heat exchanger and flow to a domestic hot water storage tank or directly into the building for use.

[0035] According to various embodiments, multiple of any of the components of the integrated heat recovery and wastewater treatment system may be provided. In various alternative embodiments, the wastewater treatment and heat recovery system may include fewer or more components than described above. For example, any of the above components or any combination of components may be provided in multiples (e.g., multiple equalization storage tanks, multiple heat exchangers, multiple pumps, etc.). In some embodiments, one or more components may be removed from the system. For example, in one embodiment, the equalization storage tank may be removed. In alternative embodiments, the wastewater treatment and heat recovery system may include any of a number of other configurations, combinations of components, sizes, shapes, etc., such as, but not limited to, those described above with respect to Figure 2 One or more components or aspects described.

[0036] Before the wastewater enters the treatment process, the wastewater may initially pass through a screening process. In some embodiments, the wastewater may pass through a screening process before heat recovery. In some embodiments, the wastewater may pass through a screening process after heat recovery. The screening process may be used to remove solid materials above a size threshold. For example, the screening process may remove materials larger than the size of a grain of sand or a golf ball. In some embodiments, the screening process may remove materials with a maximum dimension (e.g., length, width, height, diagonal, diameter) greater than or equal to about 0.1mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 5mm, 7mm, or 10mm. These materials may include inorganic or organic solid materials. The screening process may remove inorganic objects that are improperly flushed into the toilet. For example, the screening process may be used to remove inorganic objects, such as children's toys, packaging materials, or other materials that are improperly flushed into the toilet. In some cases, the screening process may use one or more sieves. The sieve may be selected from a coarse sieve, a fine sieve, and a micro sieve. In some cases, a single sieve may be used to capture larger solid materials. Alternatively, multiple screens may be provided in series or in parallel. Once the larger solid materials are removed from the wastewater, they may be discharged to a sewer or collected periodically. In another example, once the larger solid materials are removed from the wastewater, they may be treated periodically or processed off-site for reuse as a soil conditioner. Once the larger solid materials are screened from the wastewater, a valve may be used to divert the wastewater stream to a heat exchanger. In some cases, at least a portion of the wastewater may not be screened prior to entering the wastewater treatment and heat recovery process described herein.

[0037] One or more pumps can be used to move warm wastewater through a heat exchanger. The heat exchanger can be positioned in close proximity to a wastewater treatment system. Alternatively, the heat exchanger can be located at any distance from the wastewater treatment system. In some embodiments, heat recovery can occur before wastewater treatment. In some embodiments, the temperature of the warm wastewater stream before entering the wastewater treatment system is about 65°F to about 90°F. In some embodiments, the temperature of the wastewater stream before entering the wastewater treatment system is about 65°F to about 70°F, about 65°F to about 72°F, about 65°F to about 75°F, about 65°F to about 78°F, about 65°F to about 80°F, about 65°F to about 85°F, about 65°F to about 90°F, about 70°F to about 72°F, about 70°F to about 75°F, about 70°F to about 78°F, about 70°F to about 80°F, about 70°F to about 85°F, about 70°F to about 90°F. F, about 72°F to about 75°F, about 72°F to about 78°F, about 72°F to about 80°F, about 72°F to about 85°F, about 72°F to about 90°F, about 75°F to about 78°F, about 75°F to about 80°F, about 75°F to about 85°F, about 75°F to about 90°F, about 78°F to about 80°F, about 78°F to about 85°F, about 78°F to about 90°F, about 80°F to about 85°F, about 80°F to about 90°F, or about 85°F to about 90°F. In some embodiments, the temperature of the wastewater stream prior to entering the wastewater treatment system is about 65°F, about 70°F, about 72°F, about 75°F, about 78°F, about 80°F, about 85°F, or about 90°F. In some embodiments, the temperature of the wastewater stream prior to entering the wastewater treatment system is at least about 65° F., about 70° F., about 72° F., about 75° F., about 78° F., about 80° F., or about 85° F. In some embodiments, the temperature of the wastewater stream prior to entering the wastewater treatment system is at most about 70° F., about 72° F., about 75° F., about 78° F., about 80° F., about 85° F., or about 90° F.

[0038] Once the wastewater stream leaves the wastewater treatment and heat exchanger, one or more pumps can move the wastewater through the wastewater treatment system. In some embodiments, valves or pumps are used to route the wastewater through the wastewater treatment system.

[0039] The heat recovered from the wastewater can be transferred to the site or nearby where heating is needed. The recovered heat can promote on-site space and / or water heating. In some embodiments, the recovered heat energy can be converted into another form of energy. For example, the recovered heat energy can be converted into mechanical energy, electrical energy or a combination thereof. In some embodiments, the heat energy recovered from the wastewater can be used for on-site wastewater treatment processes. In some cases, the heat energy recovered from the wastewater can reduce the energy input required for the wastewater treatment process.

[0040] In some embodiments, the heat recovered from the wastewater can be used for heating domestic water on site. In other embodiments, the heat recovered from the wastewater can be used for heating treated wastewater (recycled water or recirculated water) on site. Before introducing the recovered heat, the temperature of cold domestic water can be about 40 ° F, 45 ° F, 50 ° F, 55 ° F, 60 ° F, 65 ° F, 70 ° F or 75 ° F. The heat recovered from the wastewater can be transferred to heat domestic water to a temperature of about 60 ° F, 70 ° F, 80 ° F, 90 ° F, 100 ° F, 110 ° F or 120 ° F. Domestic water can flow through a heat exchanger configured for heat transfer between two fluids. In some embodiments, cold domestic water enters a heat exchanger at a first input site, and warm wastewater enters a heat exchanger at a second input site. A heat exchanger can promote heat transfer between two fluids. In some embodiments, the heat energy present in the warm wastewater is transferred to cold domestic water, causing the domestic water temperature to rise. In some embodiments, the domestic water of this heating is used for domestic purposes on site. For example, the heated domestic water can be used for washing clothes, showering, washing clothes, etc.

[0041] In some embodiments, the heat recovery system 200 may include a heat exchanger 201, a pump 203, and a controller 205. In some cases, the pump 203 may be a variable frequency drive (VFD) pump or a single speed pump. The pump may include a motor controller that drives the electric motor by changing the frequency and voltage supplied to the electric motor so that the pump can operate at a variable speed (e.g., a flow rate range) without using an additional gearbox or switching to a different electric motor. The VFD pump is able to dynamically adjust the operation of the pump to adapt to the uneven density of the wastewater. This beneficially reduces the power consumption of the pump, reduces costs, and improves energy efficiency. A flow control valve may be used to adjust the pump discharge flow rate instead of changing the pump motor speed.

[0042] The controller 205 can perform flow control in the heat recovery system 200. In some embodiments, the controller 205 can be operably coupled to the motor controller of the pump 203 and automatically adjust the speed or other operation of the pump (e.g., on / off). In some embodiments, the controller 205 can control the flow based on sensor data. For example, the sensor data can include the temperature of the wastewater (e.g., treated or partially treated), and the controller can execute a proprietary or non-proprietary control algorithm to adjust the speed and start time of the pump. The control algorithm can maximize heat recovery while reducing system cost.

[0043] In some embodiments, the controller and / or control algorithm can be part of a process control system integrated into the wastewater treatment and heat recovery system to optimize heat recovery or control wastewater transfer time, or a combination thereof. Sensors located at the inlet / outlet of the tank, heat exchanger 201 can also be part of the process control system. The data captured by the sensors can be transmitted to the controller or process control system via cables or wirelessly.

[0044] In some cases, the control algorithm may control the flow or operation of the heat recovery system based at least in part on the state of the wastewater treatment process and / or the demand for water use in the building. In some cases, the control algorithm may be executed by the process control system so as to control both the wastewater treatment process and the heat recovery in a coordinated manner, thereby improving the overall performance of the integrated wastewater treatment and heat recovery. Wastewater collection and flow through the building network may depend on the demand and use of water at a given time. There may be certain periods of the day when more hot water flows into the wastewater collection system. For example, since the residents of the building take a hot shower before starting their day, there may be an increased amount of hot wastewater flowing into the wastewater treatment system in the morning. Similarly, the increase in hot water flow may be the result of increased use of laundry and dishwashers. In some cases, the building's demand for non-potable water is less than the amount of wastewater supplied to the integrated heat recovery and wastewater treatment system, so a portion of the building's wastewater flow may be diverted to the sewer. The process control system may execute a control algorithm to prioritize and automatically determine when wastewater needs to be diverted to the sewer to maximize heat recovery while balancing the building's non-potable water supply needs. For example, when the demand for a building's non-potable water supply is below a threshold, the building wastewater flow may be diverted to sewer without unnecessary treatment. In some cases, the control algorithm may be able to predict and / or forecast the demand for hot building water and dynamically adjust the diversion of wastewater (e.g., time window, amount, etc.) based on the predicted demand. By avoiding unnecessary treatment of unusable wastewater while capturing the energy of such water for heat recovery, the overall efficiency of heat recovery and wastewater treatment may be improved.

[0045] In some cases, the process control system can control heat recovery to maximize heat recovery capacity and maximize uptime. During times when heat recovery capacity is limited or no heat recovery capacity, the system can automatically adjust the flow rate in the heat recovery system 200, such as by controlling the pump 203 speed or shutting down the pump to save energy and limit wear on components. In some cases, based on the real-time sensed water temperature or water level in the tank, the system can determine the heat recovery capacity and can adjust the pump (e.g., slow down or shut down) based on the heat recovery capacity. For example, when the heat recovery capacity is below a threshold, the pump can be shut down.

[0046] The process control system may include sensors for measuring temperature, pressure, flow rate, or additional process / operating parameters. Temperature sensing may occur at a wastewater holding tank, at a source of water to be preheated, at the inlet and / or outlet of a heat exchanger, or at any other point in the wastewater treatment and heat recovery process. Temperature sensing may be used to track system efficiency. Temperature sensing may also be used to allow control of pump speed, and therefore heat extraction. As described above, heat recovery operations may be controlled based on real-time temperature and / or hot water demand. For example, during a period when a building requires more hot water, the pump speed may be increased to meet the increased heat recovery demand, and when the building demand decreases, the pump speed may be slowed down.

[0047] In some cases, when the temperature of the wastewater in the holding tank is above a predetermined threshold, the controller 205 can issue a command to the pump to increase the speed of the pump until the temperature drops back to a predetermined range. In some cases, when the temperature of the wastewater in the holding tank is below a predetermined threshold (indicating insufficient heat recovery capacity), the controller 205 can issue a command to the pump to reduce the speed or shut down the pump, thereby reducing operating costs and minimizing wear on components when heat recovery potential is low.

[0048] In some cases, the process control system can measure the demand for hot domestic water in the venue. In some cases, these measurements can be performed in real time. The water demand in the building or venue can be measured using an online flow meter for continuous real-time data collection. In some cases, the temperature set point for domestic hot water can be automatically determined by an online thermocouple. In some cases, the temperature set point for domestic hot water is set by an operator. The temperature set point for domestic hot water demand can vary based on various factors such as building hot water demand, time of day and time of year. The operator can set the temperature set point. The temperature set point can be adjusted to adapt to factors such as changing hot water demand, climatic conditions and seasonality. In some cases, the process control system can control the wastewater treatment process and / or heat recovery operation based on the predicted demand for hot domestic water. Predictions can be made based on historical data and / or real-time sensor data. The demand for hot domestic water can be predicted within the upcoming forecast period (such as within the next 10 minutes, 20 minutes, 30 minutes, 1 hour, 2 hours, 3 hours, etc.).

[0049] The process control system may be able to perform automated operations. In some embodiments, the process control system may protect the pump from operating under low water level conditions based at least in part on water level sensor data. This can maximize system operating time or uptime and reduce operating cost burdens. The water level of the box can be measured using an online device placed in the box. In some cases, the online device contacts the wastewater in the box. In some cases, the online device does not contact the wastewater in the box. In some cases, a hydrostatic device can be used to measure the water level in the box. The hydrostatic device may include a displacer, a bubbler, or a differential pressure transmitter, or a combination thereof. In some cases, an ultrasonic device is used to measure the water level in the box. In some cases, a laser or radar water level transmitter is used to measure the water level in the box. By continuously measuring the water level in the box, the number of water points for alarms and actions can be unlimited via programming in the control system. When a low water level condition is detected, the automatic control system can reduce the speed of the pump or shut down the pump completely. In some cases, the height of the pump suction can determine the low-low water level cutoff point because this is the physical point where the pump inhales air instead of pumping water. In one example, the low water cutoff point may be approximately 10" from the bottom of the tank. The low water cutoff may be customized and adjusted for a particular application or physical size of the component.

[0050] The heat recovery system may include one or more pumps 203 to move the warm wastewater stream to one or more heat exchangers 201. The warm wastewater stream may enter one or more heat exchangers prior to wastewater treatment. In some embodiments, the heat exchanger 201 may be a shell and tube heat exchanger. Fig. 6A and Figure 6BA shell and tube heat exchanger is shown. A shell and tube heat exchanger allows two fluids to come into thermal contact to exchange heat. In some embodiments, the first fluid is warm wastewater. In some embodiments, the second fluid is cold domestic water. In some embodiments, the second fluid is a circulating fluid, such as ammonia, water, a water-glycol mixture, or a refrigerant. The heat captured in the circulating fluid can be used for various on-site uses. In some embodiments, the two fluids include warm wastewater and a circulating fluid from a building to be heated. One fluid flows through the outside of the tube, while the second fluid flows through the tube. The fluid can be a gas phase, a liquid phase, or a combination thereof. The fluid can be single-phase or two-phase. The shell and tube heat exchanger can be operated in a parallel, cross-phase, or countercurrent arrangement. A parallel flow arrangement refers to when the shell and tube fluids enter the heat exchanger on the same side and flow to the opposite end in parallel. A countercurrent heat exchanger refers to when the shell and tube fluids enter the heat exchanger at the opposite end. The fluids flow in opposite directions and are discharged at the opposite ends of the heat exchanger. In a cross-flow shell and tube heat exchanger, the fluids flow perpendicularly to each other at an angle of approximately 90°. Fig. 6A A shell and tube heat exchanger with two inlets and two outlets is shown, where each fluid begins at its respective inlet and leaves the device at its outlet. The tube side flow passes through the tubes (fixed by metal plates called tube sheets) and exits at the tube outlets. Similarly, the shell side flow begins at the shell inlet, passes through the tubes, and exits at the shell outlet. The baffles maximize the amount of heat mixing that occurs between the shell side fluid and the fluid in the tubes. The shell and tube heat exchanger can be a U-tube heat exchanger, a fixed tube sheet heat exchanger, or a floating head heat exchanger.

[0051] In some embodiments, one or more heat exchangers may be plate and frame heat exchangers. Figure 7An example of a plate and frame heat exchanger is shown. A plate and frame heat exchanger may include two end members that hold a plurality of heat transfer plates together. A plate and frame heat exchanger allows heat transfer between two fluids using a plurality of heat transfer plates. In some embodiments, the first fluid is warm wastewater. In some embodiments, the second fluid is cold domestic water. In some embodiments, the second fluid is a circulating fluid such as ammonia, water, a water-glycol mixture, or a refrigerant. The heat captured in the circulating fluid can be used for various field uses. In some embodiments, one or more pumps move the second fluid through the heat exchanger. The two fluids can flow through alternating channels in a countercurrent manner. The fluids can be gas phase, liquid phase, or a combination thereof. The fluids can be single phase or two phase. The plates can be corrugated to create turbulence in the fluid as it flows through the heat exchanger. Such turbulence can increase the amount of heat transferred between the two fluids. The plates can be made of stainless steel, titanium, aluminum, copper, Hastelloy, Avesta 254SMO, Avesta254SLX, or any material that is ductile enough to form a pressed plate. The thickness of the plates may be between 0.5 mm and 2.5 mm, or the plates may have a thickness less than 0.5 mm or greater than 2.5 mm. The heat transfer plates may be separated by gaskets that seal the plates and arrange for fluid flow between the plates. The gaskets may prevent mixing of the two fluids in the event of damage to the interior of the heat exchanger. The heat transfer plates may be brazed together using a brazing material. The brazing material may include copper, nickel, silver, aluminum or gold, or a combination thereof.

[0052] The temperature of the wastewater stream after leaving the heat exchanger and before entering the wastewater treatment can be about 60°F to about 75°F. The temperature of the wastewater stream after leaving the heat exchanger and before entering the wastewater treatment can be about 60°F to about 62°F, about 60°F to about 64°F, about 60°F to about 65°F, about 60°F to about 66°F, about 60°F to about 68°F, about 60°F to about 70°F, about 60°F to about 72°F, about 60°F to about 74°F, about 60°F to about 75°F, about 62°F. to about 64°F, about 62°F to about 65°F, about 62°F to about 66°F, about 62°F to about 68°F, about 62°F to about 70°F, about 62°F to about 72°F, about 62°F to about 74°F, about 62°F to about 75°F, about 64°F to about 65°F, about 64°F to about 66°F, about 64°F to about 68°F, about 64°F to about 70°F, about 64 °F to about 72 °F, about 64 °F to about 74 °F, about 64 °F to about 75 °F, about 65 °F to about 66 °F, about 65 °F to about 68 °F, about 65 °F to about 70 °F, about 65 °F to about 72 °F, about 65 °F to about 74 °F, about 65 °F to about 75 °F, about 66 °F to about 68 °F, about 66 °F to about 70 °F, about 66 °F to about 72 °F, about F to about 74° F, about 66° F to about 75° F, about 68° F to about 70° F, about 68° F to about 72° F, about 68° F to about 74° F, about 68° F to about 75° F, about 70° F to about 72° F, about 70° F to about 74° F, about 70° F to about 75° F, about 72° F to about 74° F, about 72° F to about 75° F, or about 74° F to about 75° F. The temperature of the wastewater stream after leaving the heat exchanger and before entering the wastewater treatment can be about 60° F, about 62° F, about 64° F, about 65° F, about 66° F, about 68° F, about 70° F, about 72° F, about 74° F, or about 75° F.

[0053] In some embodiments, the amount of energy extracted from warm wastewater is from about 500,000 BTU / day to about 100,000,000 BTU / day, or any amount below 500,000 BTU / day or above 100,000,000 BTU / day. In some embodiments, the amount of energy extracted from warm wastewater is from about 500,000 BTU / day to about 100,000,000 BTU / day. In some embodiments, the amount of energy extracted from the warm wastewater is from about 500,000 BTU / day to about 1,000,000 BTU / day, from about 500,000 BTU / day to about 5,000,000 BTU / day, from about 500,000 BTU / day to about 20,000,000 BTU / day, from about 500,000 BTU / day to about 50,000,000 BTU / day, from about 500,000 BTU / day to about 100,000,000 BTU / day, from about 1,000,000 BTU / day to about 5,000,000 BTU / day, from about 1,000,000 BTU / day to about 20,000,000 BTU / day, from about 1,000,000 BTU / day to about To about 50,000,000 BTU / day, about 1,000,000 BTU / day to about 100,000,000 BTU / day, about 5,000,000 BTU / day to about 20,000,000 BTU / day, about 5,000,000 BTU / day to about 50,000,000 BTU / day, about 5,000,000 BTU / day to about 100,000,000 BTU / day, about 20,000,000 BTU / day to about 50,000,000 BTU / day, about 20,000,000 BTU / day to about 100,000,000 BTU / day or about 50,000,000 BTU / day to about 100,000,000 BTU / day. In some embodiments, the amount of energy extracted from warm wastewater is about 500,000 BTU / day, about 1,000,000 BTU / day, about 5,000,000 BTU / day, about 20,000,000 BTU / day, about 50,000,000 BTU / day, or about 100,000,000 BTU / day. In some embodiments, the amount of energy extracted from warm wastewater is at least about 500,000 BTU / day, about 1,000,000 BTU / day, about 5,000,000 BTU / day, about 20,000,000 BTU / day, or about 50,000,000 BTU / day. In some embodiments, the energy extracted from the warm wastewater is up to about 1,000,000 BTU / day, about 5,000,000 BTU / day, about 20,000,000 BTU / day, about 50,000,000 BTU / day, or about 100,000,000 BTU / day.Once the wastewater stream leaves the heat exchanger, one or more pumps can move the wastewater through the wastewater treatment system. In some embodiments, valves are used to divert the wastewater into the wastewater treatment system.

[0054] After entering the wastewater treatment system, wastewater can be held in a holding tank. In some examples, a holding tank can be used to hold back excess wastewater if the treatment process reaches its capacity. In some examples, a three-way valve can be used as an emergency bypass to the sewer. In an example, an emergency bypass can be used to release excess wastewater from a building to the sewer if the treatment process reaches its capacity and the holding tank is full.

[0055] Various embodiments of wastewater treatment systems and methods described herein provide wastewater treatment with improved efficiency and improved water and energy use. In some embodiments, treated solid waste can be used as fertilizer or soil conditioner. Wastewater separated from solid waste can be treated and disinfected during the treatment process, for toilets, cooling towers, laundry, irrigation landscapes or other environmental purposes. Various embodiments can be used for any one in a large number of settings and positions, to provide efficient and effective wastewater treatment.

[0056] In this application, the terms "waste", "wastewater" and "sewage" are sometimes used interchangeably. Unless these terms are specifically described as having specific meanings, they should be interpreted as interchangeable.

[0057] In some embodiments, heat recovery can occur after wastewater treatment. Once the wastewater leaves the wastewater treatment system, a valve can be used to transfer the wastewater stream to one or more heat exchangers. One or more pumps can be used to move the warm wastewater through one or more heat exchangers. The heat exchanger can be positioned in close proximity to the outlet of the wastewater treatment system or positioned at a distance from the outlet of the wastewater treatment system. In some embodiments, heat recovery can occur before and after wastewater treatment. In some embodiments, the temperature of the warm wastewater stream after leaving the wastewater treatment system is about 65°F to about 90°F. In some embodiments, the temperature of the wastewater stream after exiting the wastewater treatment system is from about 65°F to about 70°F, from about 65°F to about 72°F, from about 65°F to about 75°F, from about 65°F to about 78°F, from about 65°F to about 80°F, from about 65°F to about 85°F, from about 65°F to about 90°F, from about 70°F to about 72°F, from about 70°F to about 75°F, from about 70°F to about 78°F, from about 70°F to about 80°F, from about 70°F to about 85°F, from about 70°F to about 90°F. F, about 72°F to about 75°F, about 72°F to about 78°F, about 72°F to about 80°F, about 72°F to about 85°F, about 72°F to about 90°F, about 75°F to about 78°F, about 75°F to about 80°F, about 75°F to about 85°F, about 75°F to about 90°F, about 78°F to about 80°F, about 78°F to about 85°F, about 78°F to about 90°F, about 80°F to about 85°F, about 80°F to about 90°F, or about 85°F to about 90°F. In some embodiments, the temperature of the wastewater stream after leaving the wastewater treatment system is about 65°F, about 70°F, about 72°F, about 75°F, about 78°F, about 80°F, about 85°F, or about 90°F. In some embodiments, the temperature of the wastewater stream after leaving the wastewater treatment system is at least about 65° F., about 70° F., about 72° F., about 75° F., about 78° F., about 80° F., or about 85° F. In some embodiments, the temperature of the wastewater stream after leaving the wastewater treatment system is at most about 70° F., about 72° F., about 75° F., about 78° F., about 80° F., about 85° F., or about 90° F.

[0058] In some embodiments, the heat recovery system of the present invention can be provided as a package that can be integrated into an existing wastewater treatment system in a convenient manner. In some cases, the heat recovery system can have a small footprint, such as a complete skid-mounted system. The complete skid-mounted system can be integrated into an existing wastewater treatment process that requires heat recovery. In some embodiments, the heat recovery system may include a pump, a heat exchanger, a sensor, and a controller as described above, and may be coupled to the wastewater treatment system in a plug-and-play manner without changing the wastewater treatment system. This can facilitate easy integration of the system into a building. In some cases, the integrated wastewater treatment and heat recovery system is installed in the basement of the building. Alternatively, one or more components of the existing wastewater treatment system may need to be reconfigured to be coupled to the heat recovery system. For example, the skid-mounted heat recovery system may include all required sensors and instruments. The sensors and instruments may be tested before being installed and transported to the installation site. In some cases, the heat recovery system may utilize a temperature sensor (or other sensor) of an existing wastewater treatment system. For example, a controller of the heat recovery system may communicate with a control system of the wastewater treatment system to retrieve sensor data or other wastewater treatment status data to control a pump or operation of the heat recovery system.

[0059] In some cases, the heat recovery system of the present invention can provide the flexibility of custom design to accommodate pre-existing wastewater treatment sites. For example, the heat recovery system can be configured to scale up or down relative to the flow capacity of the existing wastewater treatment system. For example, the heat recovery system can be scaled up by increasing the speed or size of the pump to meet the flow capacity of the existing wastewater treatment.

[0060] In some cases, the functionality or management of the heat recovery system can be automatically integrated into the wastewater treatment system management software, such as a supervisory control and data acquisition (“SCADA”) system. The software can allow operators to set the heat exchanger configuration, view the real-time status of the heat recovery system and WWTP (wastewater treatment plant), and control the system.

[0061] In some embodiments, the software may provide an operator interface, allowing the operator to configure the heat exchanger system at setup and / or modify the configuration of the heat exchanger system during operation. Control algorithms may be executed to control pumps of the heat recovery system, valves of the wastewater treatment system, and other components of the system to achieve safety, heat recovery efficiency, and / or cost reduction objectives (as described elsewhere herein). Alternatively or additionally, the operator may configure the heat recovery system by directly setting system parameters (e.g., flow rate or pump speed).

[0062] In some embodiments, the integrated system herein can provide an operator interface to allow an operator to access real-time status and data about the system. For example, data collected from wastewater treatment and heat recovery systems can be displayed on a control panel. Real-time information can allow an operator to track heat recovery and other system statistics.

[0063] In some cases, the software may be able to deliver alarms in real time (e.g., system failure, pump shutoff, tank low water level, etc.). In some cases, an operator interface provided by the system may allow an operator to customize the rules for triggering alarms. For example, an operator may set a threshold for triggering an alarm, a frequency of reminders / alarms, and / or a delivery channel for the alarm (e.g., text message, email, in-app message, etc.).

[0064] In some cases, the operator interface may include a control panel, allowing the operator to control at least some of the operating parameters. For example, if little heat is available for recovery or if the system requires maintenance, the operator may be able to manually shut down the heat recovery system via the control panel.

[0065] In some embodiments, the software may provide a customer interface. The customer may be an individual or company utilizing a wastewater heat recovery system. For example, the customer may be the owner of an apartment building with a wastewater heat recovery system installed therein. The customer may be a university, and the university may utilize a wastewater heat recovery system to recover heat from wastewater throughout the university campus. The customer interface may allow the customer to view certain operational or performance statistics. In some cases, the customer interface displays the amount of heat or energy recovered from the wastewater heat recovery system. The customer interface may display cost savings associated with the installation and operation of the wastewater heat recovery system. The customer interface may display data in real time or display average data within a given time period. In some cases, the customer may not be able to modify operating parameters through the customer interface.

[0066] For example, the control panel may be a customer-facing dashboard that displays the real-time status of the system, and / or provides a summary to the customer of how the system is operating. In some cases, the customer-facing dashboard may include reporting capabilities. In some cases, only authorized users may be allowed to edit process parameters via the dashboard.

[0067] In some embodiments, the integrated wastewater treatment and heat recovery system is fully automated. The process control system can be fully automated through control and can be manually manipulated by the system operator. For example, the operator can be allowed to control the system through a supervisory control and data acquisition ("SCADA") system to force the opening / closing of pumps, adjust pump speeds, change the percentage of control valve opening, and various other operations of the system. The operator can restore the entire system or a single component to automatic operation at any time. For troubleshooting purposes, online sensors can be manually set to specific values. This beneficially allows instruments to be replaced without interrupting system operation. Additionally, this function can be used to diagnose whether automatic functions are working.

[0068] In some embodiments, the heat recovery system and / or WWTP can communicate with a remote cloud through a gateway, a building's Internet service, or via a cellular network. For example, the gateway can connect to a wide area network (e.g., the Internet) or the cloud using any TCP / IP or UDP-based backhaul (such as Ethernet, Wi-Fi, or cellular). The gateway can include a radio front end that is capable of listening to a few MHz of RF wireless spectrum at a time and / or is configured to listen to all network traffic transmitted within that spectrum. In some cases, the gateway can use a synchronized frequency hopping scheme.

[0069] In some cases, the user interface may be provided as a cloud application, such as a management console or analytics portal that may be accessed by users, operators, managers, auditors, or third-party entities.

[0070] In some cases, the graphical user interface (GUI) or user interface provided by the system herein can be presented on the display of the user device. The display may be a touch screen or may not be a touch screen. The display may be a light emitting diode (LED) screen, an organic light emitting diode (OLED) screen, a liquid crystal display (LCD) screen, a plasma screen, or any other type of screen. The display may be configured to display a user interface (UI) or a graphical user interface (GUI) presented by a mobile application or a cloud application (e.g., via an application programming interface (API) executed on a user device). Similarly, a local computing system may also provide a GUI, and a GUI may be provided on a display of a wearable device, a personnel device, or a user device at a building. The GUI may be presented by an application (e.g., via an application programming interface (API) executed on a user device). A user device may be a computing device configured to perform one or more operations consistent with the disclosed embodiments. Examples of user devices may include, but are not limited to, mobile devices, smart phones / mobile phones, tablet computers, personal digital assistants (PDAs), laptop or notebook computers, desktop computers, virtual reality systems, augmented reality systems, microphones, or any electronic devices.

[0071] The controller, process control system and various other methods herein can be implemented in hardware, software or a combination of the two. In some embodiments, the controller or process control system may include one or more processors in the form of a fine-grained spatial architecture (such as a field programmable gate array (FPGA), a digital signal processor (DSP), an application specific integrated circuit (ASIC) and / or one or more advanced RISC machines (ARM) processors), such as a programmable processor (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a general processing unit or a microcontroller). In some embodiments, the processor may be a processing unit of a computer system.

[0072] Those skilled in the art will appreciate that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or a combination of both. In order to clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been generally described above in terms of their functionality.

[0073] The various illustrative logical blocks, modules, and circuits described in conjunction with the embodiments disclosed herein may be implemented or executed with a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic controller (PLC) device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0074] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, in a software module executed by one or more processors, or in a combination of the two. The software module may reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. In an alternative, the storage medium may be integrated into the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In an alternative, the processor and the storage medium may reside in a user terminal as discrete components.

[0075] According to the description herein, as non-limiting examples, suitable computing devices include server computers, desktop computers, laptop computers, notebook computers, sub-notebook computers, netbook computers, netpad computers, set-top computers, media streaming devices, handheld computers, Internet appliances, mobile smart phones, tablet computers, personal digital assistants, video game consoles, and vehicles. Those skilled in the art will also recognize that selected televisions, video players, and digital music players with optional computer network connectivity are suitable for the systems described herein. In various embodiments, suitable tablet computers include tablet computers with brochure, tablet, and convertible configurations known to those skilled in the art.

[0076] In some embodiments, the computing device includes an operating system configured to execute executable instructions. An operating system is, for example, software including programs and data that manages the hardware of the device and provides services for executing applications. Those skilled in the art will recognize that, as non-limiting examples, suitable server operating systems include FreeBSD, OpenBSD, Linux, Mac OS X Windows and Those skilled in the art will recognize that suitable personal computer operating systems include, by way of non-limiting example, Mac OS and UNIX-like operating systems such as ). In some embodiments, the operating system is provided by cloud computing. Those skilled in the art will also recognize that, as non-limiting examples, suitable mobile smartphone operating systems include OS, Research In BlackBerry Windows OS, Windows OS, and Those skilled in the art will also recognize that suitable media streaming device operating systems include, by way of non-limiting example, Apple Google Google Amazon and Those skilled in the art will also recognize that suitable video game console operating systems include, by way of non-limiting example, Xbox Microsoft Xbox One, Wii and

[0077] In some embodiments, the systems, media, devices, and methods disclosed herein include one or more non-transient computer-readable storage media encoded with a program, the program including instructions that can be executed by an operating system of an optional networked computing device. In a further embodiment, the computer-readable storage medium is a tangible component of a computing device. In a further embodiment, the computer-readable storage medium can be optionally removed from the computing device. In some embodiments, as a non-limiting example, the computer-readable storage medium includes a CD-ROM, a DVD, a flash memory device, a solid-state memory, a disk drive, a tape drive, an optical drive, a distributed computing system (including cloud computing systems and services), etc. In some cases, the programs and instructions are permanently, substantially permanently, semi-permanently, or non-transiently encoded on the medium.

[0078] In some embodiments, the platforms, systems, media, and methods disclosed herein include at least one computer program or its use. A computer program includes a sequence of instructions that can be executed by one or more processors of a CPU of a computing device, and the sequence of instructions is written to perform a specified task. Computer-readable instructions can be implemented as program modules, such as functions, objects, application programming interfaces (APIs), computational data structures, etc. that perform specific tasks or implement specific abstract data types. Based on the disclosure provided herein, those skilled in the art will recognize that computer programs can be written in various versions of various languages, such as PLC ladder logic code.

[0079] The functionality of the computer readable instructions can be combined or distributed in various environments as desired. In some embodiments, the computer program includes one instruction sequence. In some embodiments, the computer program includes multiple instruction sequences. In some embodiments, the computer program is provided from one location. In other embodiments, the computer program is provided from multiple locations. In various embodiments, the computer program includes one or more software modules. In various embodiments, the computer program includes, in part or in whole, one or more web applications, one or more mobile applications, one or more stand-alone applications, one or more web browser plug-ins, extensions, add-ons or add-ons, or combinations thereof.

[0080] In some embodiments, the computer program includes a network application. Based on the disclosure provided herein, those skilled in the art will recognize that in various embodiments, the network application utilizes one or more software frameworks and one or more database systems. In some embodiments, the network application is implemented in a computer system such as a database system. .NET or Ruby on Rails (RoR) software framework. In some embodiments, the network application utilizes one or more database systems, which include, as non-limiting examples, relational database systems, non-relational database systems, object-oriented database systems, associative database systems, and XML database systems. In further embodiments, as non-limiting examples, suitable relational database systems include SQL Server, mySQL TM and Those skilled in the art will also recognize that in various embodiments, the web application is written in one or more versions of one or more languages. The web application may be written in one or more markup languages, presentation definition languages, client-side scripting languages, server-side coding languages, database query languages, or combinations thereof. In some embodiments, the web application is written to some extent in a markup language such as Hypertext Markup Language (HTML), Extensible Hypertext Markup Language (XHTML), or Extensible Markup Language (XML). In some embodiments, the web application is written to some extent in a presentation definition language such as Cascading Style Sheets (CSS). In some embodiments, the web application is written to some extent in a client-side scripting language such as Asynchronous Javascript and XML (AJAX), Actionscript, Javascript, or In some embodiments, the web application is written in a server-side coding language (such as Active Server Pages (ASP), Perl, Java TM , JavaServer Pages (JSP), Hypertext Preprocessor (PHP), Python TM , Ruby, Tcl, Smalltalk, In some embodiments, the web application is written in a database query language (such as Structured Query Language (SQL)). In some embodiments, the web application is integrated with an enterprise server product such as Lotus In some embodiments, the network application includes a media player component. In various further embodiments, the media player component utilizes one or more of a variety of suitable multimedia technologies, including, as non-limiting examples, HTML 5, Java TM and

[0081] In some embodiments, the computer program includes a mobile application provided to the mobile computing device. In some embodiments, the mobile application is provided to the mobile computing device when it is manufactured. In other embodiments, the mobile application is provided to the mobile computing device via a computer network described herein.

[0082] In view of the disclosure provided herein, mobile applications are created using hardware, languages, and development environments known in the art by techniques known to those skilled in the art. Those skilled in the art will recognize that mobile applications are written in several languages. As non-limiting examples, suitable programming languages ​​include C, C++, C#, Objective-C, Java, and C++. TM ,Javascript,Pascal,Object Pascal,Python TM , Ruby, VB.NET, WML and XHTML / HTML (with or without CSS) or a combination of these.

[0083] Suitable mobile application development environments are available from several sources. As non-limiting examples, commercially available development environments include AirplaySDK, alcheMo, Celsius, Bedrock, Flash Lite, .NET Compact Framework, Rhomobile, and WorkLight Mobile Platform. Other development environments are freely available and include, as non-limiting examples, Lazarus, MobiFlex, MoSync, and Phonegap. In addition, mobile device manufacturers distribute software development kits, which include, as non-limiting examples, the iPhone and iPad (iOS) SDK, the Android TM SDK, SDK, BREW SDK, OSSDK, Symbian SDK, webOSSDK and Mobile SDK.

[0084] Those skilled in the art will recognize that several commercial forums may be used to distribute mobile applications, including, by way of non-limiting example, App Store, Play, Chrome WebStore, AppWorld, App Store for Palm devices, App Catalog for webOS, Marketplace, for Ovi Store on your device, Apps and DSi Shop.

[0085] In some embodiments, the computer program includes a stand-alone application, which is a program that runs as an independent computer process, rather than an add-on to an existing process, e.g., not a plug-in. Those skilled in the art will recognize that stand-alone applications are typically compiled. A compiler is a computer program that converts source code written in a programming language into binary object code, such as assembly language or machine code. By way of non-limiting example, suitable compiled programming languages ​​include C, C++, Objective-C, COBOL, Delphi, Eiffel, Java, and Python. TM , Lisp, Python TM , Visual Basic and VB.NET or a combination thereof. Compilation is typically performed at least in part to create an executable program. In some embodiments, the computer program includes one or more executable compiled applications.

[0086] In some embodiments, a computer program includes a web browser plug-in (e.g., extension, etc.). In computing, a plug-in is one or more software components that add specific functionality to a larger software application. Software application manufacturers support plug-ins to enable third-party developers to create extension applications to support the ability to easily add new features and reduce the size of the application. When supported, plug-ins enable the functionality of customized software applications. For example, plug-ins are commonly used in web browsers to play videos, generate interactivity, scan for viruses, and display specific file types. Those skilled in the art will be familiar with several web browser plug-ins (including Player, and ). In some embodiments, the toolbar includes one or more web browser extensions, add-ons, or add-ons. In some embodiments, the toolbar includes one or more browser bars, tool belts, or desktop belts. The various functions, methods, and control algorithms described herein can be implemented in an application platform, in software, hardware, or any combination thereof.

[0087] In view of the disclosure provided herein, one skilled in the art will recognize that several plug-in frameworks can be used to implement plugins for various programming languages ​​(including, as non-limiting examples, C++, Delphi, Java, and the like). TM , PHP, Python TM and VB.NET or their combination).

[0088] A web browser (also called an Internet browser) is a software application designed for use with a network-connected computing device to retrieve, present, and navigate information resources on the World Wide Web. By way of non-limiting example, suitable web browsers include Internet Chrome, Opera and KDE Konqueror. In some embodiments, the web browser is a mobile web browser. Mobile web browsers (also known as micro-browsers, mini-browsers, and wireless browsers) are designed for use on mobile computing devices, including, by way of non-limiting example, handheld computers, tablet computers, netbook computers, subnotebook computers, smart phones, music players, personal digital assistants (PDAs), and handheld video game systems. Suitable mobile web browsers include, by way of non-limiting example, Browser, RIM Browser, Blazer, Browser, for mobile phones Internet Mobile, Basic Web, Browser, Opera Mobile and PSP TM Browser.

[0089] In some embodiments, the platform, system, medium and method disclosed herein include software, server and / or database modules, or their use. In view of the disclosure provided herein, the software module is created by using machines, software and languages ​​known in the art through techniques known to those skilled in the art. The software modules disclosed herein are implemented in a variety of ways. In various embodiments, the software module includes a file, a code segment, a programming object, a programming structure or a combination thereof. In further various embodiments, the software module includes multiple files, multiple code segments, multiple programming objects, multiple programming structures or a combination thereof. In various embodiments, as a non-limiting example, one or more software modules include a network application, a mobile application and a standalone application. In some embodiments, the software module is in a computer program or application. In other embodiments, the software module is in more than one computer program or application. In some embodiments, the software module is hosted on a machine. In other embodiments, the software module is hosted on more than one machine. In further embodiments, the software module is hosted on a distributed computing platform (such as a cloud computing platform). In some embodiments, the software module is hosted on one or more machines in one location. In other embodiments, the software module is hosted on one or more machines in more than one location.

[0090] Example 1: Energy Recovery from 30,000 Gallons of Wastewater per Day

[0091] The heat recovery system proposed in this paper can reduce costs without compromising performance. Figure 3 As shown, an apartment building may have about 30,000 gallons of wastewater per day that can be used for heat recovery. Hot water used for showering, cooking, cleaning, laundry, etc. can raise the temperature of the wastewater stream. The temperature of the wastewater can be about 75°F. 30,000 gallons of wastewater per day can flow to the basement of the apartment building and enter the wastewater treatment and heat recovery process. The thermal energy stored in the warm wastewater can be recovered and used to heat domestic water to be used in the apartment building. The equation Q = mx C x (T 1 -T A -T 2 ) calculates the amount of energy that can be extracted from the wastewater stream, where Q is the thermal energy, m is the mass flow rate of the wastewater (250,200 lbs / day), C is the specific heat of water (1 BTU / lb / °F), T 1 is the input temperature of the wastewater stream (75°F), T A is the heat exchanger approach temperature of 5°F, and T 2 is the input temperature of domestic water. Assume that the input temperature of domestic water (T 2) is 60°F, the energy that can be extracted from the wastewater stream is 2,502,000 BTU / day or 733 kWh / day. Assuming a 20 gallon per person per day hot water demand, the total hot water demand for an apartment building with 540 units and 2 people per unit can be 21,600 gallons / day. Therefore, the energy recovered from the wastewater can provide 116 BTU / gallon to heat domestic water.

[0092] Example 2: Energy Recovery from 37,000 Gallons of Wastewater per Day

[0093] like Figure 4 As shown, an apartment building may have approximately 37,000 gallons of wastewater per day that can be used for heat recovery. Hot water used for showering, cooking, cleaning, laundry, etc. can raise the temperature of the wastewater stream. The temperature of the wastewater can be approximately 75°F. 37,000 gallons of wastewater per day can flow to the basement of the apartment building and enter the wastewater treatment and heat recovery process. The thermal energy stored in the warm wastewater can be recovered and used to heat domestic water to be used in the apartment building. The equation Q = mx C x (T 1 -T A -T 2 ) calculates the amount of energy that can be extracted from the wastewater stream, where Q is the thermal energy, m is the mass flow rate of the wastewater (308,580 lbs / day), C is the specific heat of water (1 BTU / lb / °F), and T 1 is the input temperature of the wastewater stream (75°F), T A is the heat exchanger approach temperature of 5°F, and T 2 is the input temperature of domestic water. Assume that the input temperature of domestic water (T 2 ) is 60°F, the energy that can be extracted from the wastewater stream is 3,085,800 BTU / day or 904 kWh / day. Assuming a 20 gallon per person per day hot water demand, the total hot water demand for an apartment building with 540 units and 2 people per unit can be 21,600 gallons / day. Therefore, the energy recovered from the wastewater can provide 143 BTU / gallon to heat domestic water.

[0094] Example 3: Energy Recovery from 50,000 Gallons of Wastewater per Day

[0095] like Figure 5 As shown, an apartment building may have about 50,000 gallons of wastewater per day that can be used for heat recovery. Hot water used for showering, cooking, cleaning, laundry, etc. can raise the temperature of the wastewater stream. The temperature of the wastewater can be about 75°F. 50,000 gallons of wastewater per day can flow to the basement of the apartment building and enter the wastewater treatment and heat recovery process. The thermal energy stored in the warm wastewater can be recovered and used to heat domestic water to be used in the apartment building. The equation Q = mx C x (T1 -T A -T 2 ) calculates the amount of energy that can be extracted from the wastewater stream, where Q is the thermal energy, m is the mass flow rate of the wastewater (417,000 lbs / day), C is the specific heat of water (1 BTU / lb / °F), and T 1 is the input temperature of the wastewater stream (75°F), T A is the heat exchanger approach temperature of 5°F, and T 2 is the input temperature of domestic water. Assume that the input temperature of domestic water (T 2 ) is 60°F, the energy that can be extracted from the wastewater stream is 4,170,000 BTU / day or 1,222 kWh / day. Assuming a 20 gallon per person per day hot water demand, the total hot water demand for an apartment building with 540 units and 2 people per unit can be 21,600 gallons / day. Therefore, the energy recovered from the wastewater can provide 193 BTU / gallon to heat domestic water.

[0096] Although preferred embodiments of the present invention have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. The present invention is not intended to be limited to the specific examples provided in the specification. Although the present invention has been described with reference to the above description, the description and illustration of the embodiments herein are not meant to be interpreted in a limiting sense. Without departing from the present invention, those skilled in the art will now conceive of many variations, changes and substitutions. In addition, it should be understood that all aspects of the present invention are not limited to the specific description, configuration or relative proportion depending on various conditions and variables set forth herein. It should be understood that in practicing the present invention, various alternatives to the embodiments of the present invention described herein may be adopted. Therefore, it is contemplated that the present invention should also encompass any such alternatives, modifications, variations or equivalents. The appended claims are intended to define the scope of the present invention, and are intended to encompass methods and structures and their equivalents within the scope of these claims.

Claims

1. A heat recovery system, the system include: (i) a heat exchanger configured to heat water using heat energy recovered from a wastewater stream, wherein the wastewater stream is processed by a wastewater treatment system in fluid communication with the heat recovery system; as well as (ii) an apparatus configured to control a flow rate of wastewater in the heat recovery system based at least in part on real-time sensor data.

2. The system of claim 1, wherein the wastewater is at least partially treated by the wastewater treatment system prior to entering the heat recovery system.

3. The system of claim 2, wherein the heat exchanger comprises a plate and frame heat exchanger.

4. The system of claim 1, wherein the wastewater is treated by the wastewater treatment system after leaving the heat recovery system.

5. The system of claim 4, wherein the heat exchanger comprises a shell and tube heat exchanger.

6. The system of claim 1, wherein the system further comprises a screening system.

7. The system of claim 1, wherein the device is configured to control a flow rate of the wastewater based at least in part on a temperature of the wastewater flow.

8. The system of claim 7, wherein the device is configured to increase the flow rate of the wastewater when the temperature of the wastewater flow is above a threshold value.

9. The system of claim 7, wherein the device is configured to reduce a flow rate of the wastewater when the temperature of the wastewater flow is below a threshold value.

10. The system of claim 1, wherein the device is configured to control a flow rate of the wastewater through the system based at least in part on a demand for hot water.

11. The system of claim 1 , wherein the device is configured to increase the flow rate of the wastewater through the system when the demand for hot water is above a threshold.

12. The system of claim 1, wherein the device is configured to reduce the flow rate of the wastewater through the system when the demand for hot water is below a threshold.

13. The system of claim 1, wherein the system further comprises a wastewater holding tank.

14. The system of claim 13, wherein the device is configured to control the flow rate of the wastewater based at least in part on the amount of wastewater present in the wastewater holding tank.

15. The system of claim 13, wherein the device is configured to shut down when the amount of wastewater present in the wastewater holding tank is below a threshold level.

16. The system of claim 1, wherein the heat recovery system is contained within a complete skid mounted system.

17. The system of claim 16, wherein the complete skid-mounted system is configured to be coupled to an existing wastewater treatment system.

18. The system of claim 1, wherein the system is located at a location within a wastewater source.

19. The system of claim 1, wherein the wastewater source is a building, and wherein the system is located in the building.

20. The system of claim 19, wherein the system is located in a basement of the building.

21. The system of claim 1, wherein at least a portion of the wastewater used by the heat recovery system is not fully treated by the wastewater treatment system.

22. The system of claim 1, wherein the device is a pump.

23. The system of claim 1, wherein the device is a valve.

24. The system of claim 1, wherein the wastewater source is a building, and wherein the system is located outside of the building.

25. The system of claim 1, wherein the system is located off-site from the source of the wastewater.

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