CN-117266945-B - Cogeneration steam supply system based on high-pressure cylinder division and steam supply node regulation and control method

CN117266945BCN 117266945 BCN117266945 BCN 117266945BCN-117266945-B

Abstract

The invention discloses a high-pressure cylinder-based combined heat and power steam supply system and a steam supply node regulation method, wherein the high-pressure cylinder-based combined heat and power steam supply system comprises a combined heat and power generation unit and a steam supply pipeline, the combined heat and power generation unit is provided with a high-pressure cylinder, the high-pressure cylinder comprises a first section of high-pressure cylinder and a second section of high-pressure cylinder, a main steam outlet end of a boiler is connected with a steam inlet end of the first section of high-pressure cylinder, a steam outlet end of the first section of high-pressure cylinder is connected with a steam inlet end of the second section of high-pressure cylinder, a steam outlet end of the second section of high-pressure cylinder is connected with a cold re-steam inlet end of the boiler, the steam supply pipeline is provided with a first steam extraction pipeline and a second steam extraction pipeline, and a steam extraction end of the first steam extraction pipeline is connected with a steam outlet end of the first section of high-pressure cylinder. The cogeneration steam supply system based on the high-pressure cylinder division can meet the steam supply requirement of the high-pressure industry, realize the energy cascade utilization of steam, flexibly switch the steam supply heat sources and realize energy conservation and emission reduction.

Inventors

LI JIE
LIU XUELIANG
Zheng Tianshuai
GU YUHENG
XUE CHENXI
JIANG XUDONG
ZHAO RUOYU
LI BAOLEI
SUN PENG
YANG QINGCHUAN
ZHENG LIKUN
MA LIANMIN
WANG CHUNYAN
LI SHIJIN
YU XIAOBING
YANG LI

Assignees

烟台500供热有限公司
西安热工研究院有限公司
华能山东发电有限公司烟台发电厂
华能山东发电有限公司
西安西热节能技术有限公司

Dates

Publication Date: 20260508
Application Date: 20230921

Claims (10)

1. A cogeneration steam supply system based on high pressure cylinder division is characterized by comprising: The heat and power cogeneration unit is provided with a boiler and a high-pressure cylinder, wherein the high-pressure cylinder comprises a first section of high-pressure cylinder and a second section of high-pressure cylinder, the main steam outlet end of the boiler is connected with the steam inlet end of the first section of high-pressure cylinder, the steam outlet end of the first section of high-pressure cylinder is connected with the steam inlet end of the second section of high-pressure cylinder, and the steam outlet end of the second section of high-pressure cylinder is connected with the cold re-steam inlet end of the boiler; the steam supply pipeline is provided with a main pipeline, a first steam extraction pipeline and a second steam extraction pipeline, and the first steam extraction pipeline and the second steam extraction pipeline are connected in parallel at the steam inlet end of the main pipeline; The steam extraction end of the first steam extraction pipeline is connected with the steam outlet end of the first section of high-pressure cylinder so as to supply steam into the main pipeline under the low-load working condition, and the steam extraction end of the second steam extraction pipeline is connected with the steam outlet ends of the second section of high-pressure cylinder so as to supply steam into the main pipeline under the high-load working condition.
2. The cogeneration steam supply system based on the high-pressure cylinder division according to claim 1, wherein a communicating pipe is arranged between the first-stage high-pressure cylinder and the second-stage high-pressure cylinder, main steam of the boiler enters the second-stage high-pressure cylinder through the communicating pipe after working through the first-stage high-pressure cylinder, and the first steam extraction pipeline is connected with the communicating pipe.
3. The high pressure cylinder-division based cogeneration steam supply system of claim 1 further comprising a first control valve and a second control valve, wherein the first control valve is disposed on the first steam extraction pipeline and the second control valve is disposed on the second steam extraction pipeline.
4. A cogeneration steam supply system based on high pressure cylinder division according to any one of claims 1-3, wherein said cogeneration unit further comprises: The hot re-steam outlet end of the boiler is connected with the steam inlet end of the medium pressure cylinder; the steam outlet end of the medium pressure cylinder is connected with the steam inlet end of the low pressure cylinder.
5. The high-pressure cylinder-division-based cogeneration steam supply system of claim 4, wherein the cogeneration unit further comprises: The steam inlet end of the condenser is connected with the steam outlet end of the low-pressure cylinder; The deaerator, the feed liquor end of deaerator with the play liquid end of condenser is connected be provided with the condensate pump between the feed liquor end of deaerator with the play liquid end of condenser, the play liquid end of deaerator with the main steam feed liquor end of boiler is connected go out the liquid end of deaerator with be equipped with the feed water pump between the main steam feed liquor end of boiler.
6. The cogeneration steam supply system based on high-pressure cylinder separation according to claim 5, wherein a low-pressure heater is further arranged between the condenser and the deaerator, a first steam extraction port is arranged on the low-pressure cylinder, the first steam extraction port is connected with a heating medium inlet of the low-pressure heater, and a heating medium outlet of the low-pressure heater is connected with the condenser.
7. The cogeneration steam supply system based on high-pressure cylinder separation according to claim 6, wherein the low-pressure heaters are multiple, the low-pressure heaters are serially connected on a first connecting pipeline between the condenser and the deaerator, the low-pressure cylinder is provided with a plurality of first steam extraction ports, the first steam extraction ports are in one-to-one correspondence with heating medium inlets of the low-pressure heaters, the temperature of the heating medium introduced into the low-pressure heaters is gradually increased along the flowing direction of the condensed water of the first connecting pipeline, and the heating medium subjected to heat exchange in the low-pressure heaters is gradually flowed in the low-pressure heaters along the opposite direction of the flowing direction of the condensed water and finally is connected with the condenser.
8. The cogeneration steam supply system based on a high-pressure cylinder division according to claim 5, wherein a first high-pressure heater, a second high-pressure heater and a third high-pressure heater are arranged on a second connecting pipeline between a liquid outlet end of the deaerator and a main steam liquid inlet end of the boiler in series along a water supply direction, a second steam extraction port is arranged on the first section of high-pressure cylinder, a third steam extraction port is arranged on the second section of high-pressure cylinder, a fourth steam extraction port and a fifth steam extraction port are arranged on the middle pressure cylinder, the fifth steam extraction port is connected with a heating medium inlet of the deaerator, the fourth steam extraction port is connected with a heating medium inlet of the first high-pressure heater, the third steam extraction port is connected with a heating medium inlet of the second high-pressure heater, and the second steam extraction port is connected with a heating medium inlet of the third high-pressure heater.
9. The cogeneration steam supply system based on high-pressure cylinder division according to claim 8, wherein the heating medium outlet of the third high-pressure heater is connected with the heating medium inlet of the second high-pressure heater, the heating medium outlet of the second high-pressure heater is connected with the heating medium inlet of the first high-pressure heater, the heating medium outlet of the first high-pressure heater is connected with the steam inlet end of the deaerator, and/or The second steam extraction port is connected with the steam outlet end of the first section of high-pressure cylinder, and the third steam extraction port is connected with the steam outlet end of the second section of high-pressure cylinder.
10. A method for regulating and controlling a steam supply node, which is used for regulating and controlling parameters of a steam extraction node of a combined heat and power supply system based on high-pressure cylinder division according to any one of claims 1 to 9, and comprises the following steps: acquiring main steam flow; Based on the drain difference of the heater, the heater in the cogeneration steam supply system based on the high-pressure cylinder separation is divided into a drain release heater and a collecting heater; Acquiring parameters of each hydrophobic discharge type heater based on the formula (1); acquiring parameters of each collecting heater based on the formula (2); in the formula (1) and the formula (2): Tau j -1 kg of water enthalpy rise in the heater/kj.kg -1 ; q j -1 kg of heating steam heat release in the heater/kJ.kg -1 ; Gamma j -1 kg of heat release capacity in the heater for water drainage/kJ.kg -1 ; -outlet enthalpy of heater/kj.kg -1 ; h j -enthalpy of extraction of heater/kJ.kg -1 ; -the heater discharges a hydrophobic enthalpy/kj.kg -1 ; -inlet enthalpy of heater/kj.kg -1 ; -the heater enters a hydrophobic enthalpy/kj.kg -1 ; based on a heat balance principle, carrying out iterative computation on a thermodynamic system of the high-pressure cylinder-based combined heat and power generation steam supply system to obtain a main steam work amount and parameters and flow of each part of steam and water in the high-pressure cylinder-based combined heat and power generation steam supply system; and (5) calculating the heat supply parameters of the steam extraction nodes, and repeating the steps repeatedly for iteration after the heat supply parameters are not met.

Description

Cogeneration steam supply system based on high-pressure cylinder division and steam supply node regulation and control method Technical Field The invention belongs to the technical field of cogeneration, and particularly relates to a cogeneration steam supply system based on high-pressure cylinder separation and a steam supply node regulation and control method. Background The common high-pressure industrial steam supply technology of the cogeneration unit comprises four modes of cold re-steam extraction steam supply, hot re-steam extraction steam supply, main steam temperature and pressure reduction steam supply, main steam back press steam supply and the like. For a 300 MW-level thermal power generating unit, in the related technology, the cold re-steam extraction steam supply and the hot re-steam extraction steam supply are difficult to provide industrial parameters of 3MPa under the working condition of 50% THA, the steam supply requirement of 100t/h of steam supply quantity, the main steam temperature and pressure reduction steam supply can meet the high-pressure steam supply requirement under the low-load working condition, but the main steam temperature and pressure reduction steam supply is poor in economy, the three-change linkage requirement is difficult to be met, the main steam back pressure machine is used for supplying steam in a steam supply mode, a new back pressure machine factory building is needed, a back pressure machine and matched related valves are needed, the early investment cost is high, and particularly, the economic benefit is unstable under the condition of fluctuation of the steam supply requirement. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, the embodiment of the invention provides a combined heat and power steam supply system based on high-pressure cylinder separation, which can meet the steam supply requirement of high-pressure industry, realize the energy cascade utilization of steam, flexibly switch steam supply heat sources and realize energy conservation and emission reduction. The embodiment of the invention also provides a method for regulating and controlling the steam supply nodes. The combined heat and power steam supply system based on the high-pressure cylinder division of the embodiment of the invention comprises: The heat and power cogeneration unit is provided with a boiler and a high-pressure cylinder, wherein the high-pressure cylinder comprises a first section of high-pressure cylinder and a second section of high-pressure cylinder, the main steam outlet end of the boiler is connected with the steam inlet end of the first section of high-pressure cylinder, the steam outlet end of the first section of high-pressure cylinder is connected with the steam inlet end of the second section of high-pressure cylinder, and the steam outlet end of the second section of high-pressure cylinder is connected with the cold re-steam inlet end of the boiler; the steam supply pipeline is provided with a main pipeline, a first steam extraction pipeline and a second steam extraction pipeline, and the first steam extraction pipeline and the second steam extraction pipeline are connected in parallel at the steam inlet end of the main pipeline; The steam extraction end of the first steam extraction pipeline is connected with the steam outlet end of the first section of high-pressure cylinder so as to supply steam into the main pipeline under the low-load working condition, and the steam extraction end of the second steam extraction pipeline is connected with the steam outlet ends of the second section of high-pressure cylinder so as to supply steam into the main pipeline under the high-load working condition. The cogeneration steam supply system based on the high-pressure cylinder division can meet the steam supply requirement of the high-pressure industry, realize the energy cascade utilization of steam, flexibly switch the steam supply heat sources and realize energy conservation and emission reduction. In some embodiments, a communicating pipe is arranged between the first-stage high-pressure cylinder and the second-stage high-pressure cylinder, main steam of the boiler enters the second-stage high-pressure cylinder through the communicating pipe after working through the first-stage high-pressure cylinder, and the first steam extraction pipeline is connected with the communicating pipe. In some embodiments, the method further comprises providing a first control valve disposed on the first extraction line and a second control valve disposed on the second extraction line. In some embodiments, the cogeneration unit further comprises: The hot re-steam outlet end of the boiler is connected with the steam inlet end of the medium pressure cylinder; the steam outlet end of the medium pressure cylinder is connected with the steam inlet end of the low pressure cylinder. In some embodiment