CN201715492U

CN201715492U - Set back-heating system adopting different pressure ratings of steam

Info

Publication number: CN201715492U
Application number: CN2010202060803U
Authority: CN
Inventors: 李红林
Original assignee: Jinan Qiquan Thermoelectricity Co Ltd
Current assignee: Jinan Qiquan Thermoelectricity Co Ltd
Priority date: 2010-05-28
Filing date: 2010-05-28
Publication date: 2011-01-19
Anticipated expiration: 2020-05-28

Abstract

The utility model discloses a set back-heating system adopting different pressure ratings of steam. The system comprises a boiler, a steam turbine and a deaerator; one way of the output terminal of the steam turbine is connected with a secondary high pressure heater through a steam conveying pipe, and the other way is connected with a steam support feed-water pump; and the steam support feed-water pump is connected with a primary high pressure heater and a temperature and pressure reducer. The utility model solves steam supply manner that a generating set system extracts steam without corresponding pressure rating, enables a feed water back-heating system more reasonable and more economical, and improves Rankine cycle efficiency.

Description

A kind of unit heat regenerative system with different pressures grade steam

Technical field

The utility model relates to a kind of heat regenerative system, belongs to the pyroelectric technology field.

Background technology

Country for solving the supply of electric power bottleneck, has taked encouragement local construction power plant since the eighties, " who builds, and who is benefited ".Various places are for solving the supply of electric power problem of self-growth, and power plant is built in fund-raising.But along with the prosperity of country and the quick progress of technology, although many power plant also do not reach definite military service cycle of government permission " feasibility study report " originally, but the power plant that these relative scales are less can not adapt to the needs of country sustainable development because gross coal consumption rate is higher.How to reduce coal consumption, energy-saving and emission-reduction reach the requirement of cleaner production, become the problem that enterprise development will face.Therefore, enterprise will develop, and technological transformation just becomes efficient ways.

In Thermal Power Station, improving Rankine cycle thermal efficiency effective method is to adopt multistage feedwater backheat heating.Promptly extract a part of steam out, in feed-water heater, boiler feedwater is heated, supporting corresponding with it thermodynamic cycle and therrmodynamic system feedwater backheat circulation and water supply heat back system from the intergrade of steam turbine.Because extracted steam from turbine heats feedwater, has reduced the heat loss in condenser, thereby the heat of steam is fully used, improved the thermal efficiency of circulation in heater.

By analysis and research to theoretical module, drawn the backheat sum of series backheat feed temperature of the pairing standard of different pressures grade in the engineering, each equipment producer is according to different pieces of information, produce different units and the Related product model of finalizing the design, promptly there is conventional steam turbine in the power station of design routinely, design has the sum of series parameter of reasonably drawing gas, and disposes rational firing equipment.For example dispose 540 ℃ of 130T/H high-temperature high-pressure boilers of 9.8MPa, the unit of this pressure rating boiler standard configuration is the C25-8.83/0.98 extraction trubine, the boiler feed water temperature is 218 ℃, standard feedwater backheat hiigh pressure stage is that two stage pressures are respectively 1.7MPa 2.4MPa, steam turbine has two-stage and draws gas, dispose corresponding height and add, this configuration unit efficiency is reasonable, also is one of the routine configuration (seeing accompanying drawing 1) of present power plant.

Accompanying drawing 2 is seen in existing another kind of configuration, boiler links to each other with the input of steam turbine by steam pipeline, the output of steam turbine links to each other with the secondary high-pressure heater by steam pipeline, the secondary high-pressure heater links to each other with boiler by carrier pipe, the secondary high-pressure heater one-level high-pressure heater of ining succession, the one-level high-pressure heater is connected with oxygen-eliminating device, sends defeated pipe of low-pressure steam and vapour holder feed pump outside, and oxygen-eliminating device communicates with vapour holder feed pump.The 130T/H HTHP CFBB that selection pressure 9.8MPa temperature is 540 ℃, configuration 6-9.8/3.43 back pressure machine front end processor.Its technological process is that high temperature and high pressure steam at first does work in the back pressure machine, steam discharge after the back pressure machine has done work is as the admission vapour source of original C15-3.43/0.98 extraction turbine group, can improve unit parameter like this, improve unit efficiency, original steam turbine is utilized, thereby realize cascaded utilization of energy.The difficulty that the operation of this system faces is to satisfy 210 ℃ of boiler feed temperatures, and in the time of outer net pressure of steam supply 0.98MPa, how perfect solution unit does not have supporting height adds the vapour source problem.The existing vapour source 0.98MPa of therrmodynamic system draws gas, and presses the back pressure steam discharge among the 3.43MPa, if height adds on existing vapour source, 0.98MPa draws gas and feed temperature can be brought up to 165 ℃ by 150 ℃, 260T/H feedwater this moment consumption vapour 10T/H; Be heated to 216 ℃ with pressure back pressure steam discharge secondary among the 3.43MPa again, at this moment steam consumption 28T/H.The low-pressure pumping steam amount that high like this adding system is used seldom, most of is middle pressure vapour with vapour, and middle pressure vapour to be rearmounted machine admission can be directly used in generating usefulness, this backheat mode that feeds water is very uneconomical.

Summary of the invention

The purpose of this utility model provides a kind of unit heat regenerative system with different pressures grade steam.

The technical scheme that the utility model is taked:

A kind of unit heat regenerative system with different pressures grade steam, comprise boiler, steam turbine, oxygen-eliminating device, the output of steam turbine links to each other with the secondary high-pressure heater by steam pipeline one tunnel, another road links to each other with vapour holder feed pump, vapour holder feed pump in succession one-level high-pressure heater and temperature-decreased pressure reducer.

Described temperature-decreased pressure reducer is connected with the desuperheating water carrier pipe.

With boiler 1000KW electrically driven feed pump, change 1000KW back pressure vapour holder feed pump into, admission is 3.43MPa, and the back pressure steam discharge is 1.7MPa, and 1000KW vapour holder air consumption is 28T/H, adds heat exchanger with this vapour source as the one-level height and adds hot vapour source, configuration heat exchange area 280m ²Height adds heat exchanger can be heated to 190 ℃ with 260T/H water by 150 ℃, consumption vapour 20T/H; And then add hot vapour source as the secondary high pressure with pressure vapour among the 3.43MPa, feedwater is heated to 210 ℃, steam consumption 8T/H.For guaranteeing that security of system lists a 1.7/0.98MPa temperature-decreased pressure reducer with high adduction again, the feed pump steam discharge can be through temperature-decreased pressure reducer row's the 0.98MPa of power plant outer net steam-supplying system when height adds fault.

Advantage of the present utility model:

1, solves the power station machine set system and do not had the steam supply way that the relevant pressure grade is drawn gas.

2, make system's water supply heat back system more rationally economical, improved Rankine cycle efficient.

3, electrically driven feed pump changes vapour holder feed pump into and has improved unit efficiency, has reduced station service.

Description of drawings

Fig. 1 is the conventional configuration structure of the heat regenerative system of present power plant;

Fig. 2 is existing heat regenerative system structure chart;

Fig. 3 is the utility model structure chart;

Wherein: 1 boiler, 2 steam turbines, 3 oxygen-eliminating devices, 4 steam pipelines, 5 secondary high-pressure heaters, 6 one-level high-pressure heaters, 7 vapour holder feed pumps, 8 carrier pipes, 9 send the defeated pipe of low-pressure steam outside, 10 temperature-decreased pressure reducers, 11 desuperheating water carrier pipes, 12 condensing engines, 13 electrically driven feed pumps, 14 one-level low-pressure heaters, 15 secondary low-pressure heaters, 16 repeaters.

The specific embodiment

A kind of unit heat regenerative system with different pressures grade steam, comprise boiler 1, steam turbine 2, oxygen-eliminating device 3, the output of steam turbine 2 links to each other with secondary high-pressure heater 5 by steam pipeline 4 one tunnel, another road links to each other with vapour holder feed pump 7, vapour holder feed pump 7 in succession one-level high-pressure heater 6 and temperature-decreased pressure reducer 10.

Described temperature-decreased pressure reducer 10 is connected with desuperheating water carrier pipe 11.

Claims

1. unit heat regenerative system with different pressures grade steam, comprise boiler, steam turbine, oxygen-eliminating device, it is characterized in that, the output of steam turbine links to each other with the secondary high-pressure heater by steam pipeline one tunnel, another road links to each other with vapour holder feed pump, vapour holder feed pump in succession one-level high-pressure heater and temperature-decreased pressure reducer.

2. according to the described a kind of unit heat regenerative system of claim 1, it is characterized in that described temperature-decreased pressure reducer is connected with the desuperheating water carrier pipe with different pressures grade steam.