Primary network residual pressure energy recovery system of primary heat wharf sale system

Abstract

The utility model relates to a primary network residual pressure energy recovery system and method of a primary heat wharf sale system. The system comprises the primary heat wharf sale system, a residual pressure energy recovery system and a controller, the primary heat wharf sale system comprises a wharf sale primary water supply pipeline and a wharf sale primary water return pipeline which are connected with the relay pump station outlet main pipeline in parallel, the wharf sale primary water return pipeline is connected with at least two bypasses in parallel, and a residual pressure energy recovery system is installed on the bypass located on the outermost side; the excess pressure energy recovery system comprises a water-turbine generator set; the bypass is provided with an electric control valve and a manual gate valve, and the controller is electrically connected with the electric control valve and can control the opening degree of the electric control valve; according to the utility model, the increase of the number of one-time reverse pressure difference heat exchange stations and the reverse pressure difference time caused by the reduction of the water supply and return pressure difference is avoided, and the hydraulic balance effect of the whole network is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of heat supply waste heat and waste pressure energy recovery, in particular to a primary network waste pressure energy recovery system of a primary heat wholesale system. Background Art

[0002] Industrial electricity consumption accounts for about 70% of the total national electricity consumption, of which the power consumption of industrial circulating water systems accounts for 40% to 50%. There is a large amount of residual pressure energy in my country's industrial circulating water systems that is not utilized. For large-scale heating systems, municipal heating pipe networks generally have a situation where the primary pressure head of the heat exchange station after the front end and relay pump station is too high. The current operating mode basically uses electric regulating valves to lose this part of the pressure head, and the rest is consumed in the form of hydraulic coupling of the primary network, which not only causes energy waste but also affects the hydraulic balance effect of the pipe network, resulting in an increase in the number of "reverse pressure difference" heat exchange stations and the reverse pressure difference time.

[0003] With the acceleration of urbanization and the continuous growth of heating demand, the energy efficiency problem of large-scale heating systems has become increasingly prominent. In the heating system, the waste of residual pressure energy in the primary network is particularly serious, which not only causes energy waste, but also reduces the available pressure difference of the main network, affecting the stable operation of the heating system. Therefore, researching and developing an effective residual pressure energy recovery system is of great significance to improving the energy efficiency and economic benefits of the heating system. Summary of the invention

[0004] The utility model solves the technical problem by adopting the following technical solutions:

[0005] A primary network excess pressure energy recovery system of a primary heat wholesale system, the system comprising a primary heat wholesale system, an excess pressure energy recovery system and a controller;

[0006] The primary heat wholesale system includes a primary wholesale water supply pipeline and a primary wholesale return pipeline connected in parallel with the main pipeline at the relay pump station outlet, at least two bypasses are connected in parallel on the primary wholesale return pipeline, and a residual pressure energy recovery system is installed on the outermost bypass; the residual pressure energy recovery system includes a hydro-generator set;

[0007] The bypass is equipped with an electric regulating valve and a manual gate valve. The controller is electrically connected to the electric regulating valve and can control the opening of the electric regulating valve.

[0008] Furthermore, a wholesale heat meter is installed on the bulk primary return water pipeline connected to the bypass, and the wholesale heat meter is located upstream of the bypass.

[0009] Furthermore, a normally closed manual gate valve is installed on the bulk primary return water pipeline connected to the bypass, so that the water flow of the bulk primary return water pipeline passes through the bypass.

[0010] Furthermore, a flow meter is installed on the bypass of the residual pressure energy recovery system.

[0011] Furthermore, there are two bypasses, namely a first bypass and a second bypass. The residual pressure energy recovery system is installed on the first bypass, and the connection port between the second bypass and the bulk primary return water pipeline is located on the inner side of the connection port between the first bypass and the bulk primary return water pipeline.

[0012] Furthermore, a temperature sensor and a vibration sensor are also installed on the bypass of the residual pressure energy recovery system, and both the temperature sensor and the vibration sensor are connected to the controller circuit.

[0013] Furthermore, it also includes a rotation speed sensor, which obtains the rotation speed of the turbine and transmits the obtained rotation speed to the controller.

[0014] A method for recovering excess pressure energy of a primary network of a primary heat wholesale system, the method comprising:

[0015] When the hydro-turbine generator set is used for power generation, the electric regulating valve on the branch where the non-hydro-turbine generator set is located is slowly closed, and the electric regulating valve on the branch where the hydro-turbine generator set is located is slowly opened. The turbine and generator shafts begin to rotate, and the electric regulating valve on the branch where the non-hydro-turbine generator set is located continues to be closed. When the turbine speed is detected to reach the set value, the generator is turned on, and then the electric regulating valve on the branch where the hydro-turbine generator set is located is continued to be opened without exceeding the rated flow of the turbine, and the power generation power gradually increases; if the wholesale flow is greater than the rated flow of the turbine, then when the rated flow of the turbine is reached, the electric regulating valve on the branch where the non-hydro-turbine generator set is located is adjusted so that the remaining flow passes through the branch; if the wholesale flow is less than the rated flow of the turbine, the electric regulating valve on the branch where the non-hydro-turbine generator set is located is closed.

[0016] When the hydro-turbine generator set stops generating electricity, slowly close the electric regulating valve on the branch where the hydro-turbine generator set is located, and slowly open the electric regulating valve on the branch where the non-hydro-turbine generator set is located. When it is detected that the turbine speed drops to the set value, turn off the motor, stop generating electricity, and then completely close the electric regulating valve on the branch where the hydro-turbine generator set is located.

[0017] The advantages and positive effects of the utility model are:

[0018] 1. Compared with the traditional heating system, the utility model has significant advantages. First, the system can effectively recover and utilize the residual pressure energy in the primary network, avoiding energy waste. Second, by optimizing the adjustment strategy of the electric regulating valve, the return water pressure is reduced, and the available pressure difference of the main network is increased, which is conducive to the stable operation of the heating system. Finally, the system also has remote monitoring and control functions, which is convenient for operation and maintenance personnel to perform remote operation and maintenance.

[0019] 2. The utility model combines the primary network surplus pressure energy recovery with the primary heat bulk sale system, realizing the primary network surplus pressure energy utilization and safe operation of bulk sale in the peak-shaving station. Under the condition of meeting the heat supply and bulk sale operating conditions, it can avoid the increase of the return water pressure of the main network caused by the excessive return water pressure of the peak-shaving station, and avoid the increase of the number of primary "reverse pressure difference" heat exchange stations and the "reverse pressure difference" time due to the reduction of the supply and return water pressure difference, thereby improving the hydraulic balance effect of the whole network. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The technical solution of the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments, but it should be understood that these drawings are designed only for the purpose of explanation and are not intended to limit the scope of the utility model. In addition, unless otherwise specified, these drawings are only intended to conceptually illustrate the structural configurations described herein and are not necessarily drawn to scale.

[0021] Figure 1 It is a structural schematic diagram of the connection between the primary heat wholesale system provided by the embodiment of the utility model and the relay pump station and the main pipeline;

[0022] Figure 2 It is a structural schematic diagram of a primary network excess pressure energy recovery system of a primary heat wholesale system provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0023] First of all, it should be noted that the specific structure, features and advantages of the present invention will be specifically described below by way of example, but all descriptions are only for illustration and should not be understood as limiting the present invention in any way. In addition, any single technical feature described or implied in the embodiments mentioned herein, or any single technical feature displayed or implied in the drawings, can still be combined or deleted between these technical features (or their equivalents) to obtain more other embodiments of the present invention that may not be directly mentioned in this document. In addition, in order to simplify the drawings, the same or similar technical features may be marked in only one place in the same drawing.

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0025] Example 1

[0026] like Figure 1 As shown, the primary network excess pressure energy recovery system of the primary heat wholesale system provided in this embodiment includes a primary heat wholesale system Q, an excess pressure energy recovery system and a controller;

[0027] The primary heat wholesale system includes a primary wholesale water supply pipeline M and a primary wholesale return water pipeline N connected in parallel with the main pipeline at the outlet of the relay pump station D, at least two bypasses are connected in parallel on the primary wholesale return water pipeline, and a residual pressure energy recovery system is installed on the outermost bypass; the residual pressure energy recovery system includes a hydro-generator set P, the hydro-generator set includes a turbine, a generator, and a grid cabinet O, wherein the generator is connected to the grid cabinet through a cable, and the grid cabinet is connected to the low-voltage side of the transformer and automatically connected to the power grid;

[0028] The bypass is equipped with an electric regulating valve and a manual gate valve. The controller is electrically connected to the electric regulating valve and can control the opening of the electric regulating valve.

[0029] In order to monitor the wholesale flow, a wholesale heat meter is installed on the primary return water pipeline of the wholesale connected to the bypass, and the wholesale heat meter is located upstream of the bypass, for reading the primary return water main flow, and dispatching the wholesale flow, to ensure the safety of wholesale production, and in order to enable remote control, it can be considered to connect the wholesale heat meter to the controller circuit, the controller adjusts the opening of the electric regulating valve on the bypass by obtaining the data of the wholesale heat meter 5.

[0030] In this embodiment, it can be considered that there are two branches, namely the first branch A and the second branch B, the residual pressure energy recovery system is installed on the first branch, and the connection port of the second branch and the bulk primary return water pipeline is located on the inner side of the connection port of the first branch and the bulk primary return water pipeline, that is, the water inlet end of the branch where the residual pressure energy recovery system is installed is located upstream of the primary return water pipeline compared to the water inlet ends of other branches; and, in order to facilitate the adjustment of the branch flow during residual pressure energy recovery, a normally closed manual gate valve 6 is installed on the bulk primary return water pipeline. The purpose of the manual gate valve is to allow the water flow of the bulk primary return water pipeline to pass through the bypass. Therefore, the installation position of the manual gate valve is on the bulk primary return water pipeline between the water inlet and the water outlet of the branch; and, in order to monitor the practical flow of the turbine, a detection system is used In order to ensure the safe operation of the system and observe the flow through the residual pressure energy recovery system at any time, it is possible to consider installing a flow meter 7 on the bypass where the residual pressure energy recovery system is installed, and the flow meter is connected to the controller; and in order to measure the bearing temperature of the turbine and monitor the vibration of the turbine at any time, it is possible to consider installing a temperature sensor and a vibration sensor on the bypass where the residual pressure energy recovery system is installed. The vibration sensor should be set on the shaft neck and the wheel disc of the turbine unit to monitor the vibration of the rotor. The temperature sensor and the vibration sensor are both connected to the controller 8 circuit. The controller is installed in the control cabinet, and the control cabinet is connected to the central control room. At the same time, the control cabinet is also connected to the main cable of the hydropower generation. Of course, the specific connection method belongs to the conventional electrical connection and is common knowledge, so it will not be repeated here.

[0031] Since the water turbine generator has a rated flow, its rotation speed is also subject to certain restrictions. Therefore, in this embodiment, a rotation speed sensor is also included. The rotation speed sensor obtains the rotation speed of the water turbine and transmits the obtained rotation speed to the controller.

[0032] Specifically, Figure 2 As shown, the first branch A is provided with a first electric regulating valve 1 and a first manual gate valve 2, and the second branch B is provided with a second electric regulating valve 3 and a second manual gate valve 4, wherein the first manual gate valve 2 and the second manual gate valve 4 are both normally open manual gate valves. According to the demand for bulk flow, the branch pipeline regulating valve is used to adjust the flow through the turbine to ensure the normal operation of the turbine under the premise that the bulk flow meets the scheduling requirements.

[0033] Example 2

[0034] A method for recovering primary network excess pressure energy using the primary network excess pressure energy recovery system of the primary heat wholesale system in Example 1 is as follows:

[0035] When the hydro-turbine generator set is used for power generation, the electric regulating valve on the branch where the non-hydro-turbine generator set is located is slowly closed, and the electric regulating valve on the branch where the hydro-turbine generator set is located is slowly opened. The turbine and generator shafts begin to rotate, and the electric regulating valve on the branch where the non-hydro-turbine generator set is located continues to be closed. When the speed of the turbine is detected to reach 1000r / min (the power generation efficiency is low at this time. It should be noted that this value is a settable value. Each turbine is set according to the parameters of the turbine and is allowed to be different; at the same time, this value can also be changed from the perspective of economy), the generator is turned on, and then the electric regulating valve on the branch where the hydro-turbine generator set is located is continued to be opened without exceeding the rated flow of the turbine, and the power generation power gradually increases; if the wholesale flow is greater than the rated flow of the turbine, then when the rated flow of the turbine is reached, the electric regulating valve on the branch where the non-hydro-turbine generator set is located is adjusted so that the remaining flow passes through the branch; if the wholesale flow is less than the rated flow of the turbine, the electric regulating valve on the branch where the non-hydro-turbine generator set is located is closed.

[0036] When the hydro-turbine generator set stops generating electricity, slowly close the electric regulating valve on the branch where the hydro-turbine generator set is located, and slowly open the electric regulating valve on the branch where the non-hydro-turbine generator set is located. When it is detected that the turbine speed drops to 1000r / min, turn off the motor, stop generating electricity, and then completely close the electric regulating valve on the branch where the hydro-turbine generator set is located.

[0037] When the water volume needs to be adjusted during startup, the adjustment is divided into the following situations:

[0038] (1) Bulk sales flow greater than 1300m 3 / h (rated flow of the hydro-turbine generator in this embodiment), the controller controls the second electric regulating valve 3 to continue to open, so that the flow through the hydro-turbine reaches the dispatching bulk sales requirement;

[0039] (2) Bulk sales flow is less than 1300m 3 / h, the controller controls the second electric regulating valve 3 to be completely closed, and then gradually closes the turbine water inlet valve to meet the system pressure requirement. At this time, the turbine power generation efficiency is reduced;

[0040] It should be noted that the generator set is equipped with a PLC control cabinet, which can realize the protection function of the generator set. When a system fault signal is received, the first electric regulating valve 1 is automatically closed and the second electric regulating valve 3 is gradually opened to ensure that the bulk flow production operation is not affected.

[0041] The utility model relates to the field of waste heat and waste pressure utilization, and in particular to a waste pressure energy recovery system and method for a large-scale heating system. The method comprises: utilizing the waste pressure of return water to generate electricity, and the available flow rate and the available pressure difference of the hydro-generator set are in a square relationship, that is, when the pressure difference is sufficient, the available flow rate is [(flow rate / selected rated flow rate) 2 ]×rated selection pressure difference; when the flow rate is sufficient, the available pressure difference is [(pressure difference / rated pressure difference) 0.5 ]× rated flow. When the calculated power generation is greater than or equal to 20% of the rated power generation, the generator starts to generate power; when the calculated power generation is less than 20% of the rated power generation, the generator stops generating power.

[0042] The above embodiments describe the present invention in detail, but the above contents are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of application of the present invention shall still fall within the scope of the patent coverage of the present invention.

Claims

1. The primary network excess pressure energy recovery system of the primary heat wholesale system is characterized by: The system includes a primary heat wholesale system, a residual pressure energy recovery system and a controller; The primary heat wholesale system includes a primary wholesale water supply pipeline and a primary wholesale return pipeline connected in parallel with the main pipeline at the relay pump station outlet, at least two bypasses are connected in parallel on the primary wholesale return pipeline, and a residual pressure energy recovery system is installed on the outermost bypass; the residual pressure energy recovery system includes a hydro-generator set; The bypass is equipped with an electric regulating valve and a manual gate valve. The controller is electrically connected to the electric regulating valve and can control the opening of the electric regulating valve.

2. The primary network excess pressure energy recovery system of the primary heat wholesale system according to claim 1 is characterized by: A bulk heat meter is installed on the bulk primary return water pipeline connected to the bypass, the bulk heat meter is connected to the controller, and the bulk heat meter is located upstream of the bypass.

3. The primary network excess pressure energy recovery system of the primary heat wholesale system according to claim 1 is characterized by: A normally closed manual gate valve is installed on the bulk primary return water pipeline connected to the bypass, so that the water flow of the bulk primary return water pipeline passes through the bypass.

4. The primary network excess pressure energy recovery system of the primary heat wholesale system according to claim 1 is characterized by: A flow meter is installed on the bypass of the residual pressure energy recovery system, and the flow meter is connected to the controller.

5. The primary network excess pressure energy recovery system of the primary heat wholesale system according to claim 1 is characterized by: There are two bypasses, namely a first bypass and a second bypass. The residual pressure energy recovery system is installed on the first bypass, and the connection port of the second bypass and the bulk primary return water pipeline is located on the inner side of the connection port of the first bypass and the bulk primary return water pipeline.

6. The primary network excess pressure energy recovery system of the primary heat wholesale system according to claim 1 is characterized by: A temperature sensor and a vibration sensor are also installed on the bypass of the residual pressure energy recovery system, and both the temperature sensor and the vibration sensor are connected to the controller circuit.

7. The primary network excess pressure energy recovery system of the primary heat wholesale system according to claim 1 is characterized by: A rotation speed sensor is also included, which acquires the rotation speed of the water turbine and transmits the acquired rotation speed to the controller.

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