Temperature gradient distributed wastewater waste heat recovery device

Abstract

Temperature gradient distributed wastewater waste heat recovery device. This product is composed of: a sewage tank inner box body, a group of guide partition plates are installed in the sewage tank inner box body, the guide partition plates are arranged in parallel in the longitudinal direction, a group of sewage waste heat exchangers are installed in the sewage tank inner box body, the sewage waste heat exchangers are parallel to each other in the transverse direction, the top of the sewage waste heat exchanger has a sewage distribution pipe, the sewage distribution pipe is connected to the sewage inlet pipe, the sewage waste heat exchanger is connected to the sewage waste heat connecting pipe, the lower part of the sewage waste heat connecting pipe is connected to the inlet pipe, the upper part of the sewage waste heat connecting pipe is connected to the outlet pipe, and the bottom of the sewage tank inner box body is equipped with a distributed sewage recovery pipe. The present invention is used for temperature gradient distributed wastewater waste heat recovery.

Description

Technical field:

[0001] The invention relates to a temperature gradient distributed waste water waste heat recovery device. Background technology:

[0002] The existing wastewater waste heat is not recovered in large quantities, which will cause great waste and make it impossible to fully utilize a lot of wastewater waste heat. Summary of the invention:

[0003] The object of the present invention is to provide a temperature gradient distributed wastewater waste heat recovery device with the highest heat recovery efficiency.

[0004] The above purpose is achieved through the following technical solutions:

[0005] A temperature gradient distributed wastewater waste heat recovery device, which comprises: an inner box body of a sewage tank, a group of guide partition plates are installed in the inner box body of the sewage tank, the guide partition plates are arranged in parallel in the longitudinal direction, a group of sewage waste heat exchangers are installed in the inner box body of the sewage tank, the sewage waste heat exchangers are parallel to each other in the transverse direction, a sewage distribution pipe is provided on the top of the sewage waste heat exchanger, the sewage distribution pipe is connected to the sewage inlet pipe, the sewage waste heat exchanger is connected to the sewage waste heat connecting pipe, the lower part of the sewage waste heat connecting pipe is connected to the inlet pipe, and the upper part of the sewage waste heat connecting pipe is connected to the outlet pipe, a distributed sewage recovery pipe is installed at the bottom of the inner box body of the sewage tank, the inner box body of the sewage tank is installed in the outer box body of the sewage tank, and sewage tank insulation material is installed between the inner box body of the sewage tank and the outer box body of the sewage tank.

[0006] The sewage waste heat exchanger is assembled from a group of heat exchange tubes installed in parallel, each group of heat exchange tubes is composed of multiple pipes installed in parallel from top to bottom, and multiple groups of heat exchange tubes are installed in parallel and spread all over the insulated sewage tank;

[0007] A sewage distribution pipe is arranged above the box body of the sewage tank, so that the high-temperature sewage enters the sewage tank in a jet manner. The sewage distribution pipe is evenly distributed above the sewage waste heat exchanger to generate vibrations, thereby enhancing the heat exchange effect. When the sewage is at a high temperature, heat is exchanged with the refrigerant installed in the sewage waste heat exchanger in the middle and upper layers of the sewage tank. As the heat of the sewage is absorbed, the temperature gradually decreases, the specific gravity of the sewage increases, and the sewage falls into the bottom layer of the sewage tank, thereby generating a temperature gradient. The low-temperature sewage that has absorbed heat sinks to the lower layer, and is discharged in the form of overflow through the distributed sewage recovery pipe under the pressure of the new high-temperature sewage, thereby preventing heat loss.

[0008] The low-temperature refrigerant in the sewage waste heat exchanger enters from the bottom inlet of the water inlet pipe at a certain flow rate, and exchanges heat with the sewage with a temperature gradient in the sewage tank in the form of multiple tube layers. The higher the flow rate, the more significant the heat transfer effect. The high-temperature refrigerant flows out from the outlet of the upper water outlet pipe of the sewage waste heat exchanger and enters the evaporator of the unit. The heat in the refrigerant is absorbed by the refrigerant in the unit through conversion, and the low-temperature refrigerant returns to the bottom inlet of the water inlet pipe, circulates and absorbs heat to ensure the progress of the heat transfer process.

[0009] The sewage waste heat exchanger adopts an immersion structure, and the sewage waste heat exchanger is immersed in sewage. The sewage distribution pipe causes lateral scouring and temperature gradient when the high-temperature sewage enters the sewage tank, ensuring uniform and sufficient heat exchange of the high-temperature sewage. The low-temperature sewage that absorbs heat sinks to the lower layer, and is discharged in the form of overflow through the recovery device, i.e., the distributed sewage recovery pipe, under the action of the new high-temperature sewage pressure, thereby preventing heat loss.

[0010] The guide partition plates are designed to be staggered in the sewage tank, which increases the flow rate of sewage, prolongs the flow time, and fully exchanges heat. A distributed sewage recovery pipe is arranged at the bottom of the sewage waste heat exchanger to quickly discharge the low-temperature sewage.

[0011] Beneficial effects:

[0012] 1. The heat exchanger of the present invention adopts a zigzag structure of multi-tube fins to increase the heat transfer area.

[0013] 2. A distributed sewage distribution pipe is arranged on the upper part of the heat exchanger of the present invention, so that the sewage generates a temperature gradient in the longitudinal direction. A plurality of diversion devices are staggered in the middle of the sewage tank, so that the sewage increases the flow velocity in the transverse direction from right to left, prolongs the flow time, and strengthens the flushing of the outer surface of the heat exchanger. Description of the drawings:

[0014] Attached Figure 1 This is the three-dimensional structure diagram of the temperature gradient distributed wastewater waste heat recovery device of this product.

[0015] Attached Figure 2 This is the main view of the temperature gradient distributed wastewater waste heat recovery device of this product.

[0016] Attached Figure 3 This is a top view of the temperature gradient distributed wastewater waste heat recovery device of this product.

[0017] Attached Figure 4 This is a side view of the temperature gradient distributed wastewater waste heat recovery device of this product.

[0018] Attached Figure 5 This is the sewage waste heat exchanger diagram of this product. Specific implementation method:

[0019] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention.

[0020] Embodiment 1:

[0021] A temperature gradient distributed wastewater waste heat recovery device, which comprises: a sewage tank inner box body 1, characterized in that: a group of guide partition plates 10 are installed in the sewage tank inner box body, the guide partition plates 10 are arranged in parallel in the longitudinal direction, a group of sewage waste heat exchangers 2 are installed in the sewage tank inner box body, the sewage waste heat exchangers are parallel to each other in the transverse direction, the top of the sewage waste heat exchanger is provided with a sewage distribution pipe 3, the sewage distribution pipe 3 is connected to the sewage inlet pipe 4, the sewage waste heat exchanger 2 is connected to the sewage waste heat connecting pipe 5, the lower part of the sewage waste heat connecting pipe 5 is connected to the inlet pipe 7, and the upper part of the sewage waste heat connecting pipe 5 is connected to the outlet pipe 11, a distributed sewage recovery pipe 6 is installed at the bottom of the sewage tank inner box body, the sewage tank inner box body 1 is installed in the sewage tank outer box body 8, and a sewage tank insulation material 9 is installed between the sewage tank inner box body and the sewage tank outer box body.

[0022] Embodiment 2:

[0023] The temperature gradient distributed wastewater waste heat recovery device described in Example 1, the wastewater waste heat exchanger 2 is assembled by a group of heat exchange tubes installed in parallel, each group of heat exchange tubes is composed of multiple pipes installed in parallel from top to bottom, each group of heat exchange tubes has a certain height, and multiple groups of heat exchange tubes are installed in parallel to ensure that the heat exchanger is fully distributed in the insulated sewage tank;

[0024] As a preferred embodiment, the sewage waste heat exchanger 2 is designed to adopt a multi-pass fin zigzag structure, and the number of passes can be determined by numerical analysis and optimization design combined with model experiments, with the maximum heat transfer area as a constraint;

[0025] A sewage distribution pipe 3 is arranged above the box body 1 in the sewage tank, so that the high-temperature sewage enters the sewage tank in a jet manner. The sewage distribution pipe 3 is evenly distributed above the sewage waste heat exchanger 2, generating vibrations and enhancing the heat exchange effect. When the sewage is at a high temperature, it exchanges heat with the refrigerant installed in the sewage waste heat exchanger 2 in the middle and upper layers of the sewage tank. As the heat of the sewage is absorbed, the temperature gradually decreases, the specific gravity of the sewage increases, and it falls into the bottom layer of the sewage tank, generating a temperature gradient. The low-temperature sewage that has absorbed heat sinks to the lower layer, and under the pressure of the new high-temperature sewage, it is discharged in the form of overflow through the distributed sewage recovery pipe 6, thereby preventing heat loss.

[0026] The low-temperature refrigerant in the sewage waste heat exchanger 2 enters from the bottom inlet of the water inlet pipe 7 at a certain flow rate, and exchanges heat with the sewage with a temperature gradient in the sewage tank in the form of multiple tube layers. The higher the flow rate, the more significant the heat transfer effect. The high-temperature refrigerant flows out from the outlet of the upper water outlet pipe 11 of the sewage waste heat exchanger and enters the evaporator of the unit. The heat in the refrigerant is absorbed by the refrigerant in the unit through conversion, and the low-temperature refrigerant returns to the bottom inlet of the water inlet pipe 7, circulates and absorbs heat to ensure the progress of the heat transfer process.

[0027] Embodiment 3:

[0028] The temperature gradient distributed wastewater waste heat recovery device described in Example 1, the sewage waste heat exchanger 2 as a preferred solution can adopt a non-metallic heat exchanger with added heat-conducting elements, good thermal conductivity, high strength; no corrosion, no scaling, easy to clean, and convenient to install.

[0029] The sewage waste heat exchanger 2 adopts an immersion structure, and the sewage waste heat exchanger is immersed in sewage to facilitate cleaning of dirt; the insulation material is rock wool, rigid foam polyurethane, extruded polystyrene board, mineral fiber products, etc.

[0030] As a preferred solution, an antifreeze heat exchange medium can be injected into the sewage waste heat exchanger 2, and non-contact heat exchange is performed between the sewage waste heat exchanger and the sewage to ensure the safety of the hot water unit.

[0031] It is assembled from several sewage waste heat exchangers and is easy to install and maintain.

[0032] Embodiment 4:

[0033] The temperature gradient distributed wastewater waste heat recovery device described in Example 1, the sewage tank is designed with a distributed sewage distribution and recovery device, specifically: the sewage distribution pipe 3 causes lateral scouring and temperature gradient when the high-temperature sewage enters the sewage tank, ensuring that the high-temperature sewage is evenly and fully exchanged with heat, and the low-temperature sewage that is absorbed by heat sinks to the lower layer, and is discharged in the form of overflow through the recovery device, i.e., the distributed sewage recovery pipe 6, under the action of the new high-temperature sewage pressure, thereby preventing heat loss;

[0034] By designing and installing sewage distribution pipes 3 and distributed sewage recovery pipes 6 in the sewage tank, a distributed sewage distribution and recovery device is formed, which does not destroy the temperature drop layer in the sewage tank and maintains a good temperature layer change caused by water temperature.

[0035] The distributed sewage recovery pipe 6 is designed to concentrate the low-temperature sewage in the lower layer of the water tank and discharge it at the lowest temperature, thereby reducing the energy loss of sewage discharge.

[0036] Embodiment 5:

[0037] In the temperature gradient distributed wastewater waste heat recovery device described in Example 1, the guide partition plates 10 are designed to be staggered in the sewage tank. The guide partition plates 10 increase the sewage flow rate, extend the flow time, fully exchange heat, and ensure that the sewage with the lowest temperature is discharged evenly and quickly.

[0038] Embodiment 6:

[0039] In the temperature gradient distributed wastewater waste heat recovery device described in Example 1, a distributed sewage recovery pipe 6 is arranged at the bottom of the sewage waste heat exchanger to quickly discharge low-temperature sewage. At the same time, a refrigerant with a certain flow rate enters at the bottom inlet of the sewage waste heat exchanger, flows from bottom to top through the entire sewage waste heat exchanger, and fully exchanges heat with the sewage passing in the reverse direction, so that the refrigerant obtains the maximum amount of heat and the heat recovery efficiency is maximized.

[0040] Running data statistics

[0041] Since the first system was put into use in the A02 Apartment Bathing Center of Harbin Institute of Technology in 2016, the system has been continuously upgraded and optimized, with stable operation and significant energy-saving effects.

[0042]

[0043]

[0044]

[0045] In 2018, two new systems were put into use in the bathing centers of A11 Apartment and A15 Apartment of Harbin Institute of Technology. The operating data statistics in 2019 are as follows:

[0046]

[0047]

[0048] Comparative analysis of the data of energy-saving renovation of bathhouses in Harbin Institute of Technology from 2016 to 2017

[0049]

[0050]

[0051] Comparison and economic analysis of equipment investment in various operating modes for producing hot water for bathing (schools with 10,000 people)

[0052]

[0053]

[0054] Note:

[0055] 1. This analysis only considers the salaries of boiler operators, fuel costs, and electricity costs (excluding lighting) in the process of producing hot water for bathing.

[0056] 2. Since the heat pump has a three-year warranty and the gas furnace has a one-year warranty, the maintenance cost of the heat pump after three years is uncertain and will not be compared for now. The heat pump maintenance cost should be less than the gas furnace maintenance cost.

[0057] 3. From the economic analysis, it can be concluded that the operating cost of gas is greater than that of electricity, and the heat pump has the lowest operating cost.

[0058] 4. Compared with gas furnaces, the sum of the operating expenses saved and the remaining expenses of the heat pump unit can be recovered in 3 years if it can reach the design capacity. If calculated according to the actual load, it will take 5 years to recover the cost.

Claims

1. A temperature gradient distributed wastewater waste heat recovery device, characterized in that : Its composition includes: a sewage tank inner box body, a group of guide partition plates are installed in the sewage tank inner box body, the guide partition plates are arranged in parallel longitudinally, a group of sewage waste heat exchangers are installed in the sewage tank inner box body, the sewage waste heat exchangers are parallel to each other laterally, the top of the sewage waste heat exchanger is provided with a sewage distribution pipe, the sewage distribution pipe is connected to the sewage inlet pipe, the sewage waste heat exchanger is connected to the sewage waste heat connecting pipe, the lower part of the sewage waste heat connecting pipe is connected to the water inlet pipe, the upper part of the sewage waste heat connecting pipe is connected to the outlet pipe, the bottom of the sewage tank inner box body is provided with a distributed sewage recovery pipe, the sewage tank inner box body is installed in the sewage tank outer box In the body, a sewage tank insulation material is installed between the sewage tank inner box and the sewage tank outer box; the sewage waste heat exchanger is assembled by a group of heat exchange tubes installed in parallel, each group of heat exchange tubes is composed of multiple pipes installed in parallel from top to bottom, and multiple groups of heat exchange tubes are installed in parallel and spread all over the insulation sewage tank; a sewage distribution pipe is arranged above the sewage tank inner box, so that the high-temperature sewage enters the sewage tank in a jet manner, and the sewage distribution pipe is evenly distributed above the sewage waste heat exchanger to produce vibrations, thereby enhancing the heat exchange effect; when the sewage is at a high temperature, heat is exchanged with the coolant installed in the sewage waste heat exchanger in the middle and upper layers of the sewage tank. Since the heat of the sewage is absorbed, As the temperature gradually drops, the specific gravity of the sewage increases and it falls to the bottom of the sewage tank, generating a temperature gradient. The heat-absorbed low-temperature sewage sinks to the lower layer and is discharged in the form of overflow through the distributed sewage recovery pipe under the pressure of the new high-temperature sewage, thus preventing heat loss. The low-temperature coolant in the sewage waste heat exchanger enters from the bottom inlet of the water inlet pipe at a certain flow rate and exchanges heat with the sewage with a temperature gradient in the sewage tank in the form of multiple tube layers. The higher the flow rate, the more significant the heat transfer effect. The high-temperature coolant flows out from the outlet of the upper water outlet of the sewage waste heat exchanger and enters the evaporator of the unit. The heat in the coolant is absorbed by the refrigerant in the unit through conversion, and the low-temperature coolant Then it returns to the bottom entrance of the water inlet pipe, circulates and absorbs heat to ensure the progress of the heat transfer process; the sewage waste heat exchanger adopts an immersion structure, and the sewage waste heat exchanger is immersed in sewage. The sewage distribution pipe causes lateral scouring and temperature gradient when the high-temperature sewage enters the sewage tank, ensuring that the high-temperature sewage is evenly and fully exchanged with heat. The low-temperature sewage that has absorbed heat sinks to the lower layer, and under the action of the new high-temperature sewage pressure, it is discharged in the form of overflow through the recovery device, namely the distributed sewage recovery pipe, to prevent heat loss; the guide partition plate increases the sewage flow speed, prolongs the flow time, and fully exchanges heat. The distributed sewage recovery pipe is arranged at the bottom of the sewage waste heat exchanger to quickly discharge the low-temperature sewage.

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