阅读说明：本技术 一种抽汽供热量自适应的网源协调供热系统及方法 (Network source coordinated heating system and method with self-adaptive steam extraction and heating load ) 是由 翟鹏程 乔磊 尚海军 贺凯 刘圣冠 穆祺伟 雒青 于 2020-12-21 设计创作，主要内容包括：本发明公开了一种抽汽供热量自适应的网源协调供热系统及方法,汽轮机中压缸与汽轮机低压缸之间通过中低压缸连通管相连通；抽汽供热管道的入口与中低压缸连通管或者汽轮机中压缸的排汽口相连通,抽汽供热管道的出口与热网加热器的放热侧入口相连通,热网加热器的放热侧出口经疏水冷却器的放热侧与凝汽器的入口相连通；热网回水管道的出口经疏水冷却器的吸热侧与热网循环水泵的入口相连通,热网循环水泵的出口分为两路,其中一路经热网加热器的吸热侧与热网供水管道相连通,另一路经热网混水旁路与热网供水管道相连通,汽轮机低压缸的排汽口与凝汽器相连通,该系统及方法能够提高供热的可靠性,同时操作简单,便于实现,成本较低。(The invention discloses a network source coordinated heating system and a network source coordinated heating method with self-adaptive steam extraction and heating load, wherein a steam turbine medium-pressure cylinder is communicated with a steam turbine low-pressure cylinder through a medium-low pressure cylinder communicating pipe; the inlet of the steam extraction heat supply pipeline is communicated with the medium-low pressure cylinder communicating pipe or the steam exhaust port of the medium pressure cylinder of the steam turbine, the outlet of the steam extraction heat supply pipeline is communicated with the heat release side inlet of the heat supply network heater, and the heat release side outlet of the heat supply network heater is communicated with the inlet of the condenser through the heat release side of the drain cooler; the system and the method can improve the reliability of heat supply, are simple to operate, convenient to realize and low in cost at the same time.)

1. A network source coordinated heating system with self-adaptive steam extraction and heat supply capacity is characterized by comprising a steam turbine medium-pressure cylinder (14), a steam turbine low-pressure cylinder (10), a medium-low pressure cylinder communicating pipe (13), a steam extraction and heat supply pipeline, a heat supply network heater (7), a drainage cooler (3), a condenser (9), a heat supply network water return pipeline (1), a heat supply network water supply pipeline (2) and a heat supply network water mixing bypass (6);

the turbine intermediate pressure cylinder (14) is communicated with the turbine low pressure cylinder (10) through an intermediate pressure cylinder communicating pipe (13); the inlet of the steam extraction and heat supply pipeline is communicated with a medium and low pressure cylinder communicating pipe (13) or the steam exhaust port of a steam turbine medium pressure cylinder (14), the outlet of the steam extraction and heat supply pipeline is communicated with the heat release side inlet of the heat supply network heater (7), and the heat release side outlet of the heat supply network heater (7) is communicated with the inlet of the condenser (9) through the heat release side of the drain cooler (3);

the outlet of the heat supply network water return pipeline (1) is divided into two paths after passing through the heat absorption side of the drainage cooler (3), wherein one path is communicated with the heat supply network water supply pipeline (2) through the heat absorption side of the heat supply network heater (7), the other path is communicated with the heat supply network water supply pipeline (2) through the heat supply network water mixing bypass (6), and the steam exhaust port of the steam turbine low-pressure cylinder (10) is communicated with the condenser (9).

2. The network source coordinated heating system with self-adaptive steam extraction and heat supply capacity as claimed in claim 1, wherein a heating network water mixing bypass adjusting valve (5) is arranged on the heating network water mixing bypass (6).

3. The network source coordinated heating system with self-adaptive steam extraction and heat supply capacity as claimed in claim 2, wherein the steam extraction and heat supply pipeline is provided with a steam extraction pipeline stop valve (11).

4. The network source coordinated heating system with self-adaptive steam extraction and heat supply capacity as claimed in claim 2, wherein the steam extraction and heat supply pipeline is provided with a steam extraction pipeline check valve (12).

5. The network source coordinated heating system with self-adaptive steam extraction and heat supply capacity as claimed in claim 1, characterized in that the heat absorption side outlet of the heat network heater (7) is communicated with the heat network water return pipe (1) through a heat network heater water side outlet pipe (8).

6. The network source coordinated heating system with self-adaptive steam extraction and heat supply capacity according to claim 1, characterized in that an outlet of the heat supply network water return pipeline (1) is communicated with an inlet of the heat supply network circulating water pump (4) through a heat absorption side of the hydrophobic cooler (3), and an outlet of the heat supply network circulating water pump (4) is divided into two paths.

7. A network source coordinated heating method with self-adaptive steam extraction and heating amount is characterized in that the network source coordinated heating system with self-adaptive steam extraction and heating amount is based on claim 3 and comprises the following steps:

in a non-heat supply mode, exhaust steam of a turbine intermediate pressure cylinder (14) enters a heat supply network heater (7) through an intermediate pressure cylinder communicating pipe (13) to release heat;

in the heating mode, a stop valve (11) of a steam extraction pipeline and a check valve (12) of the steam extraction pipeline are fully opened, exhaust steam extracted by the steam extraction and heat supply pipeline enters a heat release side of a heat supply network heater (7) for heat release, then enters a heat release side of a drainage cooler (3) for heat release, and finally enters a condenser (9); the water of heat supply network water supply pipe (2) output divide into two the tunnel after hydrophobic cooler (3) primary heating, wherein carry out the secondary heating in getting into heat supply network heater (7) all the way, another way gets into in heat supply network mixes water bypass (6), wherein, the operating temperature in heat supply network heater (7) is the saturation temperature that corresponds under the current pressure of drawing steam, the water of output through heat supply network mixes water bypass (6) cools off the water of heat supply network heater (7) heat absorption side output, in order to ensure that the circulating water temperature in heat supply network water supply pipe (2) is the required temperature of heat supply network system, wherein, mix the proportion of two tunnel water through heat supply network and mix water bypass governing valve (5).

Technical Field

The invention belongs to the technical field of cogeneration, and relates to a network source coordinated heating system and method with self-adaptive steam extraction and heating load.

Background

Along with the increasing development of urbanization, people have greater and greater requirements for central heating. In the urban central heating system, the most common mode is to adopt a cogeneration technology to heat the circulating water of the heat supply network by using the extraction heat of the steam turbine.

No matter the steam extraction heat supply, the low-pressure cylinder zero-output heat supply or the high-back-pressure heat supply, part of steam is extracted from the steam turbine, and a heat supply network heater or a peak heater is introduced to heat the heat supply network circulating water. The steam extraction pipeline is led out from a steam extraction port of the steam turbine, and a heater is led in after the check valve, the quick closing valve, the regulating valve and the stop valve are arranged. The operating personnel of the power plant need to control the steam volume entering the heater by controlling the opening degree of the steam extraction pipeline regulating valve so as to control the temperature of the circulating water of the heat supply network, and the method is also an operation mode of steam extraction and heat supply of almost all thermal power generating units at present.

Because the peak regulation pressure of the existing thermal power generating unit is large and the load fluctuation is high, under the steam extraction and heat supply mode, operating personnel need to frequently operate a steam extraction pipeline regulating valve to control the temperature of circulating water of a heat supply network.Meanwhile, the requirement of a DCS system of a steam turbine body of the thermal power generating unit is high, the requirement of the DCS system of a heat supply network head station system is low, and the problem that equipment, interfaces, software and the like are incompatible is often caused under the condition that investment cost is considered in a power plant, the equipment, the interfaces, the software and the like need to be controlled independently, so that the operation difficulty of power plant operators is further increased. For example, the conventional 300MW unit has the heat supply area of 500 ten thousand meters²And the steam extraction amount is about 300t/h in the heating period. When the unit is 100% loaded, the steam exhaust amount of the intermediate pressure cylinder is about 700t/h, and the valve opening of the heat supply steam extraction pipeline is smaller to ensure the steam extraction amount of 300 t/h; when the unit is 75% loaded, the medium-pressure steam exhaust amount is about 500t/h, and the opening degree of a heat supply steam extraction pipeline valve is larger for ensuring the steam extraction amount of 300 t/h. Meanwhile, in order to ensure that the axial thrust of the unit does not change greatly, the steam extraction pipeline valve under different unit loads needs to be matched with the opening degree of the heat supply valve of the middle-low pressure cylinder communicating pipe for adjustment.

The heat and power cogeneration unit is used as a main heat source of a city, the heat supply reliability of the heat and power cogeneration unit is an important factor influencing the life quality of residents, and valve flowing media such as a regulating valve of a heat supply steam extraction pipeline are high-temperature steam, so that frequent operation is needed and faults are easy to occur, so that a power plant is forced to purchase valves with extremely high price or increase standby heat sources to improve the heat supply reliability.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a network source coordinated heating system and method with self-adaptive steam extraction and heating capacity, which can improve the reliability of heating and have the advantages of simple operation, convenient realization and lower cost.

In order to achieve the purpose, the network source coordinated heating system with the self-adaptive steam extraction and heat supply capacity comprises a steam turbine medium-pressure cylinder, a steam turbine low-pressure cylinder, a medium-low pressure cylinder communicating pipe, a steam extraction and heat supply pipeline, a heat network heater, a drainage cooler, a condenser, a heat network water return pipeline, a heat network circulating water pump, a heat network water supply pipeline and a heat network water mixing bypass;

the turbine medium pressure cylinder is communicated with the turbine low pressure cylinder through a medium and low pressure cylinder communicating pipe; the inlet of the steam extraction heat supply pipeline is communicated with the medium-low pressure cylinder communicating pipe or the steam exhaust port of the medium pressure cylinder of the steam turbine, the outlet of the steam extraction heat supply pipeline is communicated with the heat release side inlet of the heat supply network heater, and the heat release side outlet of the heat supply network heater is communicated with the inlet of the condenser through the heat release side of the drain cooler;

the outlet of the heat supply network water return pipeline is communicated with the inlet of the heat supply network circulating water pump through the heat absorption side of the drainage cooler, the outlet of the heat supply network circulating water pump is divided into two paths, one path of the outlet is communicated with the heat supply network water supply pipeline through the heat absorption side of the heat supply network heater, the other path of the outlet is communicated with the heat supply network water supply pipeline through a heat supply network water mixing bypass, and the steam exhaust port of the low-pressure cylinder of the steam turbine is communicated with the condenser.

And a heat supply network water mixing bypass regulating valve is arranged on the heat supply network water mixing bypass.

The steam extraction heat supply pipeline is provided with a steam extraction pipeline stop valve and a steam extraction pipeline check valve.

The heat absorption side outlet of the heat supply network heater is communicated with the heat supply network water return pipeline through a water side outlet pipeline of the heat supply network heater.

A network source coordinated heat supply method with self-adaptive steam extraction heat supply capacity comprises the following steps:

in a non-heat supply mode, exhaust steam of a middle pressure cylinder of the steam turbine enters a heat supply network heater through a middle and low pressure cylinder communicating pipe to release heat;

in the heating mode, a stop valve of the steam extraction pipeline and a check valve of the steam extraction pipeline are fully opened, exhaust steam extracted by the steam extraction and heat supply pipeline enters a heat release side of a heat supply network heater for heat release, then enters a heat release side of a drainage cooler for heat release, and finally enters a condenser; the water of heat supply network water supply pipe output divide into two the tunnel after hydrophobic cooler preliminary heating, wherein carry out the secondary heating in getting into the heat supply network heater all the way, another way enters into in the heat supply network mixes the water bypass, wherein, the operating temperature in the heat supply network heater is the saturation temperature that corresponds under the current pressure of drawing steam, the water of mixing water bypass output through the heat supply network cools off the water of heat supply network heater heat absorption side output, in order to ensure that the circulating water temperature in the heat supply network water supply pipe is the required temperature of heat supply network system, wherein, mix the proportion of water of two tunnels through the heat supply network and adjust water bypass governing valve.

The invention has the following beneficial effects:

the network source coordinated heating system and the method for self-adapting steam extraction and heat supply capacity have the advantages that during specific operation, the regulating valve and the quick closing valve on the original steam extraction pipeline are removed, the system investment is reduced compared with the conventional steam extraction and heat supply, low-pressure cylinder zero-output and high-back-pressure heat supply modes, the operation difficulty of a steam turbine centralized control system is reduced, the steam extraction capacity of a unit is not required to be operated through a steam turbine centralized control chamber in a heat supply mode, the automatic adjustment of parameters of a heat supply network can be realized only by adjusting the opening degree of a water mixing bypass regulating valve of the heat supply network, the system and the control logic are simple, the reliability of heat supply is greatly improved, the matching relation between a steam turbine body DCS system of a thermal power generating unit and a heat supply network head station DCS system is effectively reduced, the heat extraction capacity of the unit is adaptively matched only.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Wherein, 1 is a heat supply network return water pipeline, 2 is a heat supply network water supply pipeline, 3 is a hydrophobic cooler, 4 is a heat supply network circulating water pump, 5 is a heat supply network water mixing bypass regulating valve, 6 is a heat supply network water mixing bypass, 7 is a heat supply network heater, 8 is a heat supply network heater water side outlet pipeline, 9 is a condenser, 10 is a steam turbine low pressure cylinder, 11 is a steam extraction pipeline stop valve, 12 is a steam extraction pipeline check valve, 13 is a medium and low pressure cylinder communicating pipe, and 14 is a steam turbine medium pressure cylinder.

Detailed Description

The invention is described in further detail below with reference to the accompanying drawings:

referring to fig. 1, the network source coordinated heat supply system with self-adaptive steam extraction and heat supply capacity of the invention comprises a steam turbine intermediate pressure cylinder 14, a steam turbine low pressure cylinder 10, a medium and low pressure cylinder communicating pipe 13, a steam extraction and heat supply pipeline, a heat supply network heater 7, a drainage cooler 3, a condenser 9, a heat supply network water return pipeline 1, a heat supply network circulating water pump 4, a heat supply network water supply pipeline 2 and a heat supply network water mixing bypass 6; the turbine intermediate pressure cylinder 14 is communicated with the turbine low pressure cylinder 10 through an intermediate pressure cylinder communicating pipe 13; the inlet of the steam extraction heat supply pipeline is communicated with a medium and low pressure cylinder communicating pipe 13 or the steam exhaust port of a steam turbine medium pressure cylinder 14, the outlet of the steam extraction heat supply pipeline is communicated with the heat release side inlet of the heat supply network heater 7, and the heat release side outlet of the heat supply network heater 7 is communicated with the inlet of the condenser 9 through the heat release side of the drain cooler 3; the outlet of the heat supply network water return pipeline 1 is communicated with the inlet of the heat supply network circulating water pump 4 through the heat absorption side of the hydrophobic cooler 3, the outlet of the heat supply network circulating water pump 4 is divided into two paths, one path is communicated with the heat supply network water supply pipeline 2 through the heat absorption side of the heat supply network heater 7, the other path is communicated with the heat supply network water supply pipeline 2 through the heat supply network water mixing bypass 6, and the steam exhaust port of the steam turbine low-pressure cylinder 10 is communicated with the condenser 9.

A heating network water mixing bypass adjusting valve 5 is arranged on the heating network water mixing bypass 6; the steam extraction heat supply pipeline is provided with a steam extraction pipeline stop valve 11 and a steam extraction pipeline check valve 12; the heat absorption side outlet of the heat supply network heater 7 is communicated with the heat supply network water return pipeline 1 through a heat supply network heater water side outlet pipeline 8.

The invention relates to a network source coordinated heat supply method with self-adaptive steam extraction and heat supply quantity, which comprises the following steps:

in a non-heat supply mode, the exhaust steam of the steam turbine intermediate pressure cylinder 14 enters the heat supply network heater 7 through the intermediate pressure cylinder communicating pipe 13 to release heat;

in the heating mode, a stop valve 11 and a check valve 12 of the steam extraction pipeline are fully opened, the exhaust steam extracted by the steam extraction and heat supply pipeline enters a heat release side of a heat supply network heater 7 for heat release, then enters a heat release side of a drain cooler 3 for heat release, and finally enters a condenser 9; the water output by the heat supply network water supply pipeline 2 is primarily heated by the drainage cooler 3 and then divided into two paths, wherein one path enters the heat supply network heater 7 for secondary heating, and the other path enters the heat supply network water mixing bypass 6, wherein the operation temperature in the heat supply network heater 7 is the corresponding saturation temperature under the current steam extraction pressure, the temperature of the water output by the heat supply network heater 7 is the saturation temperature minus the heater, and according to different units, the water temperature is 120-190 ℃ in the state, because the circulating water in the heat supply network water mixing bypass 6 is not heated by the heat supply network heater 7, the water output by the heat absorption side of the heat supply network heater 7 is cooled by the water output by the heat supply network water mixing bypass 6, so as to ensure that the circulating water temperature in the heat supply network water supply pipeline 2 is the temperature required by a heat supply network system, and the proportion of the two paths of water is adjusted by the heat supply network.

In the heating mode, the temperature of the drain water output by the heat release side of the heat supply network heater 7 is higher than the temperature corresponding to the condenser 9, so that the drain water output by the heat release side of the heat supply network heater 7 is cooled by the heat release side of the drain cooler 3 and then enters the condenser 9, and because the temperature of the drain water output by the heat release side of the heat supply network heater 7 is higher, in order to improve the economy of a unit, the condensed water can also be used as a cold source of the drain cooler 3 to cool the drain water of the heat supply network and then enter the condenser 9. Corresponding subcritical unit, because hydrophobic temperature is higher, also can directly introduce the hydrophobic of the heat release side output of heat supply network heater 7 into unit deaerator or pressurizing heater to no matter how unit electrical load, heat supply heat load change, the unit all need not to adjust the admission steam volume of extraction steam pipe, heat supply network circulating water temperature is confirmed according to the saturation temperature of steam self, only need simple PID control heat supply network mix water bypass governing valve 5, can realize the automatically regulated of heat supply network parameter.

The invention is characterized in that:

1) the regulating valve and the quick closing valve on the original steam extraction pipeline are removed, the check valve 12 of the steam extraction pipeline and the stop valve 11 of the steam extraction pipeline are in a fully open state in the whole heat supply period, and the steam turbine operator does not need to control the steam extraction pipeline valve to adjust the parameters of the heat supply network;

2) no matter how the unit electrical load and the heating heat load change, the water temperature at the outlet of the heating network heater 7 is the saturated temperature corresponding to the extraction pressure of the steam turbine in the current state, and the heater end difference is reduced;

3) the water mixing amount of the water mixing bypass of the heat supply network is used for controlling the water supply temperature of the heat supply network;

4) the opening degree of the heat supply network water mixing bypass regulating valve 5 tracks the water supply temperature of the heat supply network, and the automatic regulation of the parameters of the heat supply network can be realized only by simple PID control.

The above-mentioned contents are only for illustrating the technical idea of the present invention, and the protection scope of the present invention is not limited thereby, and any modification made on the basis of the technical idea of the present invention falls within the protection scope of the claims of the present invention.