CN101846330A

CN101846330A - Steam supply system for steam air heater of utility boiler

Info

Publication number: CN101846330A
Application number: CN201010207224A
Authority: CN
Inventors: 魏熙臣; 魏来
Original assignee: Individual
Current assignee: Individual
Priority date: 2010-06-23
Filing date: 2010-06-23
Publication date: 2010-09-29
Anticipated expiration: 2030-06-23
Also published as: CN101846330B

Abstract

The invention discloses a steam supply system for a steam air heater of a utility boiler, which relates to a steam supply system for a steam air heater. The invention solves the problems that: the exhausted steam heat of the deaerator is not utilized, the working medium is not recovered, the operation cost is high, the quality of the steam supplied by the steam air heater is too high, and the heat-recovering efficiency of the steam turbine generator unit is low. The steam supply system comprises the steam air heater, a deaerator stream-exhausting valve, a deaerator, a steam supply tube and a draining tube, a steam intake header of the steam air heater is communicated with the deaerator through the steam supply tube, the deaerator steam-exhausting valve is mounted on the steam supply tube, and a draining header of the steam air heater is provided with the draining tube. The invention can ensure that the heat of the steam exhausted by the deaerator can be sufficiently utilized and that all of the working medium can be recovered; the quality of the steam supplied by the steam air heater is decreased; the temperature-reducing water for the steam supplied by the steam air heater is dispensed with, energy can be utilized according to quality, and the heat-recovering efficiency of the steam turbine generator unit is increased. The invention also reduces the operation cost of electricity generation. The invention is applicable to utility boilers.

Description

A kind of steam supply system for steam air heater of utility boiler

Technical field

The present invention relates to a kind of steam supply system for steam air heater of utility, be specifically related to a kind of steam supply system for steam air heater of utility boiler, belong to thermal power engineering field, power station.

Background technology

In the thermal power plant that the low temperature season area is arranged, for preventing the boiler tail generation cold end corrosion of being heated, boiler fan, primary air fan major part are furnished with steam air heater, the steam air heater thermal source derives from the station-service vapour system, steam air heater adopts high-order the layout usually, arrange drain trap at low level, the hydrophobic flow by gravity that leans on is beaten to oxygen-eliminating device with drainage pump to drain trap again.Station-service steam generally all has the degree of superheat about 100 ℃, because the superheated steam exothermic coefficient than the little 50-100 of steam condensing coefficient doubly, for improving the exchange capability of heat of steam air heater, generally will give the steam air heater steam cooling with desuperheating water, makes steam near the full temperature of closing.There is following problem in steam supply system for steam air heater of utility:

Problem 1 :Oxygen-eliminating device is the equipment that thermal power plant generally adopts, in order to guarantee deaerating effect, get rid of oxygen in water, oxygen-eliminating device all is provided with blast pipe, in deaeration, also to get rid of a large amount of full steam that closes, its displacement is generally at the 0.2-0.5% of its work water yield, with the 300MW unit is example, the oxygen-eliminating device inflow is greatly about 1000 tons/hour, displacement will reach the 2-5 ton/hour, this part steam discharge all is directly to enter atmosphere to have slatterned traditionally, the heat of deaerator exhaust does not obtain utilizing, and working medium does not obtain reclaiming.

Problem 2: the technology of multinomial recovery deaerator exhaust heat and working medium appearred in recent years, Granted publication number for CN2771654Y, Granted publication day be April 12 in 2006 day, be called power station deaerator exhaust recycle device; Granted publication number for CN2932094Y, Granted publication day be Augusts 8 in 2007 day, be called power boiler deaerator exhaust retracting device; Granted publication number for CN201233004Y, Granted publication day be Mays 6 in 2009 day, be called the deaerator exhaust retracting device.Above-mentioned patented technology without exception all be to adopt condensate water or therrmodynamic system moisturizing directly or indirectly to cool off deaerator exhaust to reclaim its heat and working medium, though adopt such way of recycling to make the steam discharge major part of oxygen-eliminating device obtain recovery, but comprehensively analyze its influence to unit thermodynamic system, when reclaiming, also to pay certain cost: though this part steam has obtained recovery, but change the influence of condensate water or water supplementing method to full factory economy, condensate water is directly advanced oxygen-eliminating device or moisturizing and is directly advanced oxygen-eliminating device influence is bigger to unit economy, the existing argumentation in many data quantitatively calculated in this part influence, therefore, by reclaiming the heat of deaerator exhaust with the cooling of moisturizing or condensate water, be very limited to the raising of full factory economy.

Problem 3: the quality of steam air heater steam supply generally all is higher than the deaerator exhaust quality, there is the bigger degree of superheat, in order to guarantee the heat exchange effect of steam air heater, usually adopt condensate water vapor (steam) temperature to be reduced near saturation temperature as desuperheating water, the quality of steam air heater steam supply was underutilized, because of cooling has reduced condensing water flow to steam air heater with condensate water, reduced the Turbo-generator Set effectiveness of regenerator again.

Summary of the invention

The objective of the invention is to be utilized in order to solve the deaerator exhaust heat, working medium is reclaimed, the too high and low problem of Turbo-generator Set effectiveness of regenerator of quality of operating cost height, steam air heater steam supply, and then provides a kind of steam supply system for steam air heater of utility boiler.

Technical scheme of the present invention is: a kind of steam supply system for steam air heater of utility boiler comprises steam air heater, deaerator exhaust valve, oxygen-eliminating device, steam supply pipe and drain pipe, the inlet steam header of described steam air heater is communicated with oxygen-eliminating device by steam supply pipe, described deaerator exhaust valve is installed on the steam supply pipe, on the hydrophobic header of described steam air heater drain pipe is installed.

The present invention compared with prior art has following effect: 1, the present invention is fully used the heat of deaerator exhaust the supply hot vapour source of deaerator exhaust as steam air heater, and working medium all obtains reclaiming.2, can satisfy the needs of steam air heater when the normal displacement of oxygen-eliminating device is not enough by the way that strengthens displacement, because oxygen-eliminating device discharges is saturated steam, its quality is far below with the superheated steam under the equal pressure, thereby reduced the quality of steam air heater steam supply; Cancelled steam air heater steam supply desuperheating water, helped having improved the Turbo-generator Set effectiveness of regenerator by the matter energy.3, the present invention has also reduced the generator operation cost.

Description of drawings

Fig. 1 is an integrally-built front view of the present invention, and Fig. 2 is the integrally-built front view of embodiment.

The specific embodiment

The specific embodiment one: present embodiment is described in conjunction with Fig. 1, a kind of steam supply system for steam air heater of utility boiler of present embodiment comprises steam air heater 1, deaerator exhaust valve 3, oxygen-eliminating device 4, steam supply pipe 6 and drain pipe 10, the inlet steam header 1-1 of described steam air heater 1 is communicated with oxygen-eliminating device 4 by steam supply pipe 6, described deaerator exhaust valve 3 is installed on the steam supply pipe 6, on the hydrophobic header 1-2 of described steam air heater 1 drain pipe 10 is installed.

Described steam air heater 1 is finned steam air heater, rib-type steam air heater or light pipe formula steam air heater, and it is a prior art.Present embodiment is applicable to that particularly the oxygen-eliminating device maximum pressure is lower than the situation of steam air heater design pressure.

The specific embodiment two: in conjunction with Fig. 1 present embodiment is described, the deaerator exhaust valve 3 of present embodiment is the deaerator exhaust control valve.So be provided with, effectively prevent steam air heater 1 superpressure.Other composition is identical with the specific embodiment one with annexation.

The specific embodiment three: present embodiment is described in conjunction with Fig. 1, the steam-supplying system of present embodiment also increases air bleeding valve 2 and blast pipe 5, have a plurality of steam vent 1-1-1 on the upper surface of the inlet steam header 1-1 of described steam air heater 1, described blast pipe 5 is responsible for 5-2 by exhaust and a plurality of exhaust branch pipe 5-1 forms, the end of each exhaust branch pipe 5-1 all is communicated with corresponding steam vent 1-1-1, the other end of each exhaust branch pipe 5-1 all is responsible for 5-2 with exhaust and is communicated with, and described air bleeding valve 2 is installed in exhaust and is responsible on the 5-2.So be provided with, the air that is collected in the inlet steam header 1-1 is in time discharged, prevent to influence heat exchange.Other composition is identical with the specific embodiment one or two with annexation.

The specific embodiment four: present embodiment is described in conjunction with Fig. 1, the steam-supplying system of present embodiment also increases steam mixer 7, auxiliary steam control valve 8, auxiliary steam header 9 and air vent pipework 11, described steam mixer 7 is installed on the steam supply pipe 6, and be communicated with steam supply pipe 6, described steam mixer 7 is communicated with auxiliary steam header 9 by air vent pipework 11, and described auxiliary steam control valve 8 is installed on the air vent pipework 11.So be provided with, be applicable to that auxiliary steam pressure is higher than the unit of oxygen-eliminating device pressure, during unit starting, use auxiliary steam header 9 to the steam air heater steam supply, when unit load lower, adopt auxiliary steam as steam supply source or filling source during oxygen-eliminating device 4 insufficient pressures, regulate displacement, effectively prevent steam air heater 1 superpressure according to the needs of oxygen-eliminating device deoxygenation.Other composition is identical with the specific embodiment one, two or three with annexation.

Described steam mixer 7 is a prior art, can select existing vapor mixing devices such as penetrating vapour vapor extractor, steam ejection collector-shoe gear, steam pressure adaptation or common threeway for use according to steam pressure.

Embodiment (referring to Fig. 2): the steam supply of steam air heater 1 is taken from oxygen-eliminating device 4 steam discharges, installing deaerator exhaust control valve on steam supply pipe 6, be used for regulating the operating pressure of steam air heater, on the inlet steam header 1-1 of steam air heater 1, have several exhaust outlets 1-1-1, by blast pipe 5 exhausts, the air bleeding valve 2 of installing can be controlled capacity on the blast pipe 5.Auxiliary steam header 9 is injected into steam mixer 7 by air vent pipework 11 with steam, installing auxiliary steam control valve on air vent pipework 11, be used for regulating the auxiliary steam evaporation capacity for engine, oxygen-eliminating device 4 steam discharges and auxiliary steam mix the back by steam mixer 7 and use vapour for steam air heater 1.The present invention can unite use with draining system, being about to exhaust person in charge 5-2 is communicated with drain pipe 10, on the drain pipe 10 between exhaust person in charge 5-2 and the steam air heater 1, fluid flowmeter 13 and drain regulating valve 14 are installed, the end of drain pipe 12 is equipped with condenser 15, fluid flowmeter 13 is used for measuring hydrophobic flow, is used for controlling the deaerator exhaust amount summer.Hydrophobicly directly drain in the condenser 15 by drain pipe 10, the drain regulating valve 14 of installing is used for regulating the hydrophobic liquid level in the steam air heater 1 on drain pipe 10, changes the heat exchange amount of steam air heater 1 by the variation of liquid level.Keep steam air heater 1 to have certain pressure in the present invention and the draining system cooperation, the operating pressure of dependence steam air heater 1 and the pressure reduction of condenser 15 are with the hydrophobic condenser 15 that is discharged to, and the liquid level of regulating in the steam air heater 1 by the aperture of drain regulating valve 14 changes the evaporation capacity for engine of steam air heater 1 and exerting oneself of steam air heater 1.

Claims

1. steam supply system for steam air heater of utility boiler, it is characterized in that: described steam-supplying system comprises steam air heater (1), deaerator exhaust valve (3), oxygen-eliminating device (4), steam supply pipe (6) and drain pipe (10), the inlet steam header (1-1) of described steam air heater (1) is communicated with oxygen-eliminating device (4) by steam supply pipe (6), described deaerator exhaust valve (3) is installed on the steam supply pipe (6), on the hydrophobic header (1-2) of described steam air heater (1) drain pipe (10) is installed.

2. a kind of steam supply system for steam air heater of utility boiler according to claim 1 is characterized in that: deaerator exhaust valve (3) is the deaerator exhaust control valve.

3. a kind of steam supply system for steam air heater of utility boiler according to claim 1 and 2, it is characterized in that: described steam-supplying system also comprises air bleeding valve (2) and blast pipe (5), have a plurality of steam vents (1-1-1) on the upper surface of the inlet steam header (1-1) of described steam air heater (1), described blast pipe (5) is responsible for (5-2) by exhaust and a plurality of exhaust branch pipe (5-1) is formed, one end of each exhaust branch pipe (5-1) all is communicated with corresponding steam vent (1-1-1), the other end of each exhaust branch pipe (5-1) all is responsible for (5-2) with exhaust and is communicated with, and described air bleeding valve (2) is installed in exhaust and is responsible on (5-2).

4. a kind of steam supply system for steam air heater of utility boiler according to claim 3, it is characterized in that: described steam-supplying system also comprises steam mixer (7), auxiliary steam control valve (8), auxiliary steam header (9) and air vent pipework (11), described steam mixer (7) is installed on the steam supply pipe (6), and be communicated with steam supply pipe (6), described steam mixer (7) is communicated with auxiliary steam header (9) by air vent pipework (11), and described auxiliary steam control valve (8) is installed on the air vent pipework (11).