Pressure-isolating equivalent medium exchange heat supply system based on positive displacement pump

Abstract

The utility model discloses a heat supply system for pressure-isolating equivalent medium exchange based on a positive displacement pump, which comprises a primary network water supply pipe and a primary network water return pipe which are connected with a heat source, and a secondary network water supply pipe and a secondary network water return pipe which are connected with a user, and the primary network water supply pipe is connected with the secondary network water supply pipe through a water supply pressure-isolating component. The primary network water return pipe and the secondary network water return pipe are connected through a water return pressure isolation assembly, the water supply pressure isolation assembly and the water return pressure isolation assembly are positive displacement pumps or adjusting valves, and at least one of the water supply pressure isolation assembly and the water return pressure isolation assembly adopts the positive displacement pump. Primary network water and secondary network water are communicated through the positive displacement pump to conduct equivalent medium exchange, heat transfer is achieved, the pressure of the primary network and the pressure of the secondary network are isolated, and the effects of being low in return water temperature and high in heat supply efficiency are achieved. The system is suitable for existing or newly-built pressure separation stations, heat exchange stations, direct supply stations or mixed water direct supply stations.

Description

Technical Field

[0001] The utility model relates to the field of urban heating systems, in particular to a heating system based on pressure-isolating equal-volume medium exchange of a positive displacement pump. Background Art

[0002] At present, there are two main forms of heating stations in urban heating systems: indirect heat exchange stations and mixed water direct supply stations. Indirect heat exchange stations use heat exchangers to exchange heat between the primary and secondary sides. The heat exchangers generally use plate heat exchangers or tube heat exchangers. However, since the primary and secondary water are not directly connected during heat exchange in plate heat exchangers and tube heat exchangers, the primary return water temperature is high and the heat exchange efficiency is low.

[0003] The mixed water direct supply station directly mixes the primary high-temperature water and the low-temperature secondary water in a mixing tank for heat exchange. Compared with the indirect heat exchange method, the mixed water direct supply method has the advantages of low return water temperature and high heating efficiency. In the existing (mixed water) direct supply system, centrifugal pumps are basically used. When the centrifugal pump stops due to power outages, the secondary side pressure is easily affected by the primary side pressure, resulting in overpressure or underpressure. Overpressure will cause pipe bursting, and underpressure will cause exhaust, causing the (mixed water) direct supply system to operate unstable and unsafe. Utility Model Content

[0004] The utility model provides a heat supply system based on pressure-isolating equal volume medium exchange of a positive displacement pump, which has the effect of preventing water from flowing between the primary network and the secondary network in the event of a power outage, isolating the primary network and the secondary network to maintain their respective pressures, and effectively solving the problem of overpressure and underpressure in the secondary network, thereby making the (mixed water) direct supply system run stably. The specific technical solution is as follows:

[0005] A heat supply system based on pressure-isolating equal volume medium exchange with a positive displacement pump, comprising a primary network water supply pipe and a primary network return pipe connected to a heat source, and a secondary network water supply pipe and a secondary network return pipe connected to a user, the primary network water supply pipe and the secondary network water supply pipe are connected via a water supply pressure isolating assembly, the primary network return pipe and the secondary network return pipe are connected via a return water pressure isolating assembly, the water supply pressure isolating assembly and the return water pressure isolating assembly are positive displacement pumps or regulating valves, and at least one of the water supply pressure isolating assembly and the return water pressure isolating assembly uses a positive displacement pump.

[0006] Furthermore, a water mixing pump is provided between the secondary network water supply pipe and the secondary network return pipe, and the water mixing pump can mix the secondary network return water with the primary network supply water.

[0007] Furthermore, a primary network water supply temperature sensor is provided on the primary network water supply pipe, a primary network return water temperature sensor is provided on the primary network return pipe, and a water supply pressure isolation component or a volume pump of the return water pressure isolation component is connected to a counter.

[0008] Furthermore, the positive displacement pump is one of a screw pump, a vane pump, a gear pump, a Roots pump, and a reciprocating pump.

[0009] Furthermore, both the water supply pressure isolation component and the return water pressure isolation component use positive displacement pumps, and the water supply pressure isolation component and the return water pressure isolation component are connected through a constant speed operation mechanism, which can enable equal volume medium exchange between the primary network and the secondary network.

[0010] Furthermore, the volumetric pumps of the water supply pressure isolation component and the return water pressure isolation component are one or more connected in parallel, and the number of the volumetric pumps of the water supply pressure isolation component and the return water pressure isolation component is equal.

[0011] Furthermore, a primary network water supply pressure sensor is provided on the primary network water supply pipe, a primary network return water pressure sensor is provided on the primary network return pipe, a secondary network water supply pressure sensor is provided on the secondary network water supply pipe, and a secondary network return water pressure sensor is provided on the secondary network return pipe.

[0012] Furthermore, when the primary network pressure is lower than the secondary network pressure, the water supply pressure isolation component adopts a positive displacement pump, and the return water pressure isolation component adopts a regulating valve.

[0013] Furthermore, when the primary network pressure is greater than the secondary network pressure, the water supply pressure isolation component adopts a regulating valve and the return water pressure isolation component adopts a volumetric pump.

[0014] The utility model discloses a heat supply system based on pressure isolation equal volume medium exchange of a volumetric pump, which realizes heat transfer by connecting primary network water with secondary network water through a volumetric pump, and isolates the pressure of the primary network from that of the secondary network, and has the effects of low return water temperature and high heating efficiency. It is suitable for existing or newly built pressure isolation stations, heat exchange stations, direct supply stations or mixed water direct supply stations.

[0015] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those of ordinary skill in the art. The accompanying drawings are only used for the purpose of illustrating the preferred embodiment and are not considered to be limiting of the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0017] Figure 1 This is a schematic diagram of a screw pump in a positive displacement pump used in both the water supply pressure isolation component and the return water pressure isolation component of the utility model;

[0018] Figure 2It is a schematic diagram of adding a water mixing pump when both the water supply pressure isolation assembly and the return water pressure isolation assembly of the utility model adopt a screw pump in a positive displacement pump;

[0019] Figure 3 It is a schematic diagram of adding a sensor and a controller when both the water supply pressure isolation assembly and the return water pressure isolation assembly of the utility model adopt a screw pump in a positive displacement pump;

[0020] Figure 4 It is a schematic diagram of adding a water mixing pump when both the water supply pressure isolation assembly and the return water pressure isolation assembly of the utility model adopt the vane pump in the positive displacement pump;

[0021] Figure 5 It is a schematic diagram of adding a water mixing pump when both the water supply pressure isolation assembly and the return water pressure isolation assembly of the utility model use the gear pump in the positive displacement pump;

[0022] Figure 6 It is a schematic diagram of adding a water mixing pump when both the water supply pressure isolation assembly and the return water pressure isolation assembly of the utility model adopt Roots pumps among the positive displacement pumps;

[0023] Figure 7 It is a schematic diagram of adding a water mixing pump when both the water supply pressure isolation assembly and the return water pressure isolation assembly of the utility model adopt a reciprocating pump in a positive displacement pump;

[0024] Figure 8 This is a schematic diagram of the utility model in which the water supply pressure isolation component adopts a screw pump in a positive displacement pump, and the return water pressure isolation component adopts a regulating valve;

[0025] Fig. 9 This is a schematic diagram of the utility model in which the return water pressure isolation component adopts a screw pump in a positive displacement pump, and the water supply pressure isolation component adopts a regulating valve. DETAILED DESCRIPTION

[0026] In order to better understand the purpose, function and specific design scheme of the utility model, the following is a further detailed description of a pressure-isolating equal-amount medium exchange heating system based on a positive displacement pump of the utility model in conjunction with the accompanying drawings.

[0027] like Figure 1-9As shown, a heat supply system based on pressure-isolating equal volume medium exchange of a displacement pump of the utility model comprises a primary network water supply pipe 8 and a primary network return pipe 9 connected to a heat source 17 (power plant or boiler room), and a secondary network water supply pipe 10 and a secondary network return pipe 11 connected to a user 18. The primary network water supply pipe 8 and the secondary network water supply pipe 10 are connected via a water supply pressure isolating assembly 1, and the primary network return pipe 9 and the secondary network return pipe 11 are connected via a return water pressure isolating assembly 2. Both the water supply pressure isolating assembly 1 and the return water pressure isolating assembly 2 are displacement pumps or regulating valves, and at least one of the water supply pressure isolating assembly 1 and the return water pressure isolating assembly 2 adopts a displacement pump, so that when the displacement pump is not working, water will not cross between the primary network and the secondary network, thereby isolating the primary network and the secondary network to maintain their respective pressures.

[0028] Specifically, a positive displacement pump is a pump that uses the change in volume inside the pump cylinder to transport liquid. However, the positive displacement pump in this application is not for pressurized water delivery, but for using the characteristics of a positive displacement pump to make the amount of water entering the secondary network from the primary network roughly equal to the amount of water discharged from the secondary network, thereby ensuring that the amount of water in the secondary network does not increase or decrease, and making the water pressure in the secondary network stable. The existing application scope of positive displacement pumps is for pressurized water delivery, rather than for equal exchange of medium (water) in two different circulation pipelines.

[0029] like Figure 2 and Figure 4-7 As shown, when the utility model is applied to mixed water heating, a mixing water pump 23 is provided between the secondary network water supply pipe 10 and the secondary network return water pipe 11, and the secondary network return water can be mixed with the primary network supply water, thereby mixing water for heating.

[0030] Preferably, in order to make the heat supply system based on the pressure isolation equal volume medium exchange of the utility model have the function of heat metering, a primary network water supply temperature sensor 13 is arranged on the primary network water supply pipe 8, a primary network return water temperature sensor 14 is arranged on the primary network return water pipe 9, and the positive displacement pump of the water supply pressure isolation component 1 or the return water pressure isolation component 2 is connected to the counter 12, and the temperature difference measured by the primary network water supply temperature sensor 13 and the primary network return water temperature sensor 14 is calculated, and the characteristic of the positive displacement pump that the volume is certain each time is used to achieve heat metering.

[0031] Preferably, in order to monitor the pressure in real time, a primary network water supply pressure sensor 19 is provided on the primary network water supply pipe 8, a primary network return water pressure sensor 20 is provided on the primary network return water pipe 9, a secondary network water supply pressure sensor 21 is provided on the secondary network water supply pipe 10, and a secondary network return water pressure sensor 22 is provided on the secondary network return water pipe 11.

[0032] The utility model utilizes that the flow rate of the volumetric pump is only related to the number of movements, and has nothing to do with the pressure of the liquid inlet and the liquid outlet (the liquid inlet pressure can be less than or greater than the liquid outlet pressure, and has nothing to do with the pressure difference between the two). In this way, the primary network circulation pressure and the secondary network circulation pressure can be isolated, the medium water is exchanged between the two circulation loops, and the primary network and the secondary network can maintain their required pressure conditions. In the existing (mixed water) direct supply system, a centrifugal pump is used, and the secondary network pressure is easily affected by the primary network pressure, forming overpressure or underpressure. Overpressure can cause pipe bursting, and underpressure can cause exhaust, causing the (mixed water) direct supply system to operate unstably and unsafely. The utility model utilizes this characteristic of the volumetric pump. Even when the volumetric pump stops, the primary network and the secondary network will not cross water, so that the primary network and the secondary network can maintain their own pressures, effectively solving the problem of overpressure and underpressure in the secondary network, so that the (mixed water) direct supply system can operate stably.

[0033] The positive displacement pump may be one of a screw pump, a vane pump, a gear pump, a Roots pump, and a reciprocating pump.

[0034] Embodiment 1

[0035] like Figure 1-7 As shown, the water supply pressure isolating assembly 1 and the return water pressure isolating assembly 2 of this embodiment both adopt volumetric pumps, the water supply inlet 3 of the water supply pressure isolating assembly 1 is connected to the primary network water supply pipe 8, the water supply outlet 4 of the water supply pressure isolating assembly 1 is connected to the secondary network water supply pipe 10, the return water inlet 5 of the return water pressure isolating assembly 2 is connected to the secondary network return water pipe 11, the return water outlet 6 of the return water pressure isolating assembly 2 is connected to the primary network return water pipe 9, the water supply pressure isolating assembly 1 and the return water pressure isolating assembly 2 are connected by a constant speed running mechanism 7, the constant speed running mechanism 7 can make equal volume medium exchange between the primary network and the secondary network, and isolate the pressure between the primary network and the secondary network, so as to realize the primary network circulation and the secondary network circulation running at different water pressures.

[0036] The constant speed running mechanism 7 can adopt a mechanical geometric transmission mechanism (including gears, belts, etc.) to realize the constant speed running of the water supply pressure isolation component 1 and the return water pressure isolation component 2. For example, the pump shafts of the two positive displacement pumps of the water supply pressure isolation component 1 and the return water pressure isolation component 2 are connected by geometric gears, one is the driving shaft and the other is the driven shaft. When the driving shaft runs one circle, the driven shaft runs one circle at the same time, thereby ensuring that the running speeds of the two pumps are consistent.

[0037] The constant speed operation mechanism 7 can also adopt an electrical mechanism (including: power frequency, variable frequency, DC speed regulation) to realize the constant speed operation of the water supply pressure isolation component 1 and the return water pressure isolation component 2. For example: using a frequency converter to control the two pumps of the water supply pressure isolation component 1 and the return water pressure isolation component 2, so that the running speed of the two pumps can be guaranteed to be consistent; or using two frequency converters to control the two pumps respectively, and using a controller or a speed regulator to control the two frequency converters to have the same frequency, so as to ensure the running speed of the two pumps to be consistent.

[0038] The constant speed operation mechanism 7 can also adopt an automatic control method (logic calculation speed regulation) to realize the constant speed operation of the water supply pressure isolation component 1 and the return water pressure isolation component 2. For example: according to the speed of one pump fed back by the sensor, the controller is used to adjust the speed of the other pump so that the speeds of the two pumps are constant.

[0039] During actual use of this embodiment, even if the primary network supply pressure is higher than the secondary network supply pressure, when the positive displacement pump stops, the primary network water supply will not enter the secondary network, and the secondary network water pressure will not increase. If a centrifugal pump is used, the primary network water will enter the secondary network, causing the secondary network pressure to be overpressured, leading to pipe burst; similarly, even if the secondary network return water pressure is higher than the primary network return water pressure, when the positive displacement pump stops, the secondary network return water will not enter the primary network, and the secondary network water pressure will not be reduced. If a centrifugal pump is used, the secondary network water will enter the primary network, causing the secondary network pressure to be underpressured, leading to exhaust.

[0040] Therefore, no matter the water pressure of the primary network water supply (liquid inlet) is higher than the water pressure of the secondary network water supply (liquid outlet), or the water pressure of the secondary network water supply (liquid inlet) is higher than the water pressure of the primary network return water (liquid outlet), the purpose of using an even number of positive displacement pumps running at equal speeds is not to pressurize water delivery, but to exchange approximately equal volumes of media and to achieve operation of the primary network circulation and the secondary network circulation at different water pressures.

[0041] In this embodiment, the volumetric pumps of the water supply pressure isolation component 1 and the return water pressure isolation component 2 can be one or multiple in parallel, as long as the number of volumetric pumps of the water supply pressure isolation component 1 and the return water pressure isolation component 2 is equal.

[0042] like Figure 3As shown, a heat supply system based on pressure isolation equal volume medium exchange of a displacement pump in this embodiment further includes a master controller 24, a primary network water supply pipe 8 is provided with a primary network water supply temperature sensor 13 and a primary network water supply pressure sensor 19, a primary network return water pipe 9 is provided with a primary network return water temperature sensor 14 and a primary network return water pressure sensor 20, a secondary network water supply pipe 10 is provided with a secondary network water supply temperature sensor 15 and a secondary network water supply pressure sensor 21, and a secondary network return water pipe 11 is provided with a secondary network return water temperature sensor 16 and a secondary network return water pressure sensor The water supply pressure isolation component 1 is connected to the counter 12, and the master controller 24 is connected to the primary network water supply temperature sensor 13, the primary network water supply pressure sensor 19, the primary network return water temperature sensor 14, the primary network return water pressure sensor 20, the secondary network water supply temperature sensor 15, the secondary network water supply pressure sensor 21, the secondary network return water temperature sensor 16, the secondary network return water pressure sensor 22, the counter 12 and the constant speed operation mechanism 7. According to the pressure and temperature at each position, the flow rate of the positive displacement pump is controlled overall intelligently to ensure the stable operation of the system. The master controller 24 can be a PLC controller or a single chip microcomputer.

[0043] Embodiment 2

[0044] like Figure 8 As shown, the difference between this embodiment and the first embodiment is that the water supply pressure isolation component 1 of this embodiment adopts a positive displacement pump, and the return water pressure isolation component 2 adopts a regulating valve. This embodiment is suitable for use when the pressure of the primary network is lower than that of the secondary network. A controller is used to control the positive displacement pump and the regulating valve respectively to realize the water pressure or temperature control of the secondary network.

[0045] Embodiment 3

[0046] like Fig. 9 As shown, the difference between this embodiment and the first embodiment is that the water supply pressure isolation component 1 of this embodiment adopts a regulating valve, and the return water pressure isolation component 2 adopts a positive displacement pump. This embodiment is suitable for use when the primary network pressure is greater than the secondary network. A controller is used to control the positive displacement pump and the regulating valve respectively to achieve secondary network water pressure or temperature control.

[0047] The utility model discloses a heat supply system based on pressure isolation equal volume medium exchange of a volumetric pump, which realizes heat transfer by connecting primary network water with secondary network water through a volumetric pump, and isolates the pressure of the primary network from that of the secondary network, and has the effects of low return water temperature and high heating efficiency. It is suitable for existing or newly built pressure isolation stations, heat exchange stations, direct supply stations or mixed water direct supply stations.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A heat supply system based on pressure isolation equal volume medium exchange of a positive displacement pump, characterized in that: It includes a primary network water supply pipe and a primary network return pipe connected to the heat source, and a secondary network water supply pipe and a secondary network return pipe connected to the user. The primary network water supply pipe and the secondary network water supply pipe are connected via a water supply pressure isolation component, and the primary network return pipe and the secondary network return pipe are connected via a return water pressure isolation component. The water supply pressure isolation component and the return water pressure isolation component are positive displacement pumps or regulating valves, and at least one of the water supply pressure isolation component and the return water pressure isolation component uses a positive displacement pump.

2. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 1, characterized in that: A mixing pump is provided between the secondary network water supply pipe and the secondary network return pipe, and the mixing pump can mix the secondary network return water with the primary network supply water.

3. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 1, characterized in that: A primary network water supply temperature sensor is arranged on the primary network water supply pipe, a primary network return water temperature sensor is arranged on the primary network return water pipe, and a water supply pressure isolation component or a volume pump of the return water pressure isolation component is connected to a counter.

4. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 1, characterized in that: The positive displacement pump is one of the following: a screw pump, a vane pump, a gear pump, a Roots pump, and a reciprocating pump.

5. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 1, characterized in that: The water supply pressure isolation assembly and the return water pressure isolation assembly both use positive displacement pumps, and the water supply pressure isolation assembly and the return water pressure isolation assembly are connected through a constant speed operation mechanism, which can enable equal volume medium exchange between the primary network and the secondary network.

6. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 5, characterized in that: The volumetric pumps of the water supply pressure isolation component and the return water pressure isolation component are one or more connected in parallel, and the number of the volumetric pumps of the water supply pressure isolation component and the return water pressure isolation component is equal.

7. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 1, characterized in that: A primary network water supply pressure sensor is provided on the primary network water supply pipe, a primary network return water pressure sensor is provided on the primary network return pipe, a secondary network water supply pressure sensor is provided on the secondary network water supply pipe, and a secondary network return water pressure sensor is provided on the secondary network return pipe.

8. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 1, characterized in that: When the primary network pressure is lower than the secondary network pressure, the water supply pressure isolation component uses a positive displacement pump and the return water pressure isolation component uses a regulating valve.

9. A heat supply system based on pressure isolation and equal volume medium exchange of a positive displacement pump as claimed in claim 1, characterized in that: When the primary network pressure is greater than the secondary network pressure, the water supply pressure isolation component uses a regulating valve and the return water pressure isolation component uses a positive displacement pump.

Images