CN205655697U - Two backpressure condenser optimal operation devices - Google Patents

Abstract

The utility model discloses a two backpressure condenser optimal operation devices, this two backpressure condenser optimal operation devices include high back pressure condenser, low back pressure condenser and circulating pipe way, and the circulating water sets up two sets of bypasses and control flap on the road, and the bypass cross -over connection still is provided with a plurality of temperature measurement stations and flowmeter at the both ends of low back pressure condenser. The utility model discloses it has following advantage to compare prior art: the utility model belongs to a single control low back pressure condenser circulating water flow, circulating water flow does not have the influence to high back pressure side condenser, through the utility model provides a formula and measurement station and valve control system can reduce the steam turbine heat consumption rate so that low back pressure side condenser vacuum does not get into loaded backpressure district, the temperature reduces relatively because the influence of circulating water bypass, high back pressure side condenser circulating water are intake, reduces high back pressure side steam extraction temperature indirectly to further reduce the steam turbine heat consumption rate.

Description

A kind of double pressure condenser optimized operating device

Technical field

This utility model relates to steam turbine control technical field, and the most double back pressure turbine condenser optimizations are transported The method of row and control system.

Background technology

Steam turbine is blocked back pressure and is referred to that the steam flow rate in steam turbine exhaust stage blade exit is close to the velocity of sound level (Mach at this Several about 0.95) back pressure time, under normal conditions, it is relevant to steam turbine throttle flow, and different throttle flows has different obstruction Back pressure value, steam turbine throttle flow is the least, and it is the lowest that steam turbine blocks back pressure.

After turbine back pressure is less than blocking back pressure, under same Steam Turbine generated energy, thermal loss of steam turbine rate raises.

The double back pressure turbine back pressure of thermal power plant is only in winter, when circulating cooling coolant-temperature gage is relatively low, and low back pressure side steam turbine Back pressure just can be less than blocking back pressure.

After thermal power plant operations staff finds that turbine back pressure is less than obstruction back pressure at present, two kinds of measures are used to improve steam turbine Back pressure:

(1) change water circulating pump operation number of units maybe will be followed pump and change low cruise into, reduce circulating water flow, low back pressure be coagulated Vapour device back pressure raises.

This measure can make low back pressure back pressure of condenser higher than blocking back pressure, reduces thermal loss of steam turbine rate, but also makes originally Just being not less than the high back pressure back pressure of condenser rising blocking back pressure, increase units consumption, synthesis result, this operation not necessarily saves Energy.

(2) double pressure condenser pumped vacuum systems water ring vacuum pump only runs 1, high and low back pressure condenser evacuation system System uses series model.

This measure can make low back pressure back pressure of condenser higher than blocking back pressure, reduces thermal loss of steam turbine rate.If but due to outward Cause low back pressure side Vacuum System Tightness of Steam Turbines in reason to reduce, owing to pumped vacuum systems uses series model, and run One vacuum pump, then can make low back pressure side back pressure of condenser raise, and thermal loss of steam turbine rate increases, and be difficult to be run personnel and send out Feel.

Utility model content

The purpose of this utility model is to overcome the deficiencies in the prior art, it is provided that a kind of double pressure condenser optimization runs Device.

This utility model is achieved through the following technical solutions: a kind of double pressure condenser optimized operating device, including High back pressure condenser, low back pressure condenser and circulating water line, circulating water line is divided into the first circulating water line and second to follow Ring water lines, the first circulating water line and the second circulating water line all flow to high back pressure condenser from low back pressure condenser, and it is special Levying and be: be provided with the first bypass on the first circulation waterway, the first bypass cross-over connection is at the two ends of low back pressure condenser, second Being provided with the second bypass on circulation waterway, the second bypass is also connected across the two ends of low back pressure condenser, and the first bypass is provided with First controls valve, and the second bypass is provided with the second control valve.

As further improvement of these options, the first circulating water line is provided with the first temperature point, Being provided with the second temperature point on two-cycle pipeline, the first temperature point is arranged on the outlet upstream of the first bypass, and second Temperature point is arranged on the outlet upstream of the second bypass.

As further improvement of these options, the first circulating water line is provided with the 3rd temperature point, Be provided with the 4th temperature point on two-cycle pipeline, the 3rd temperature point be arranged on the first bypass with the first circulating water line The upstream of point, the second temperature point is arranged on the upstream of the second bypass and the second circulating water line.

As further improvement of these options, the first bypass is additionally provided with first-class gauge, in the second bypass On be provided with second gauge.

As further improvement of these options, the first circulating water line is provided with the 3rd effusion meter, second Be provided with the 4th effusion meter on circulating water line, the 3rd effusion meter be arranged on the first bypass with the first circulating water line point Downstream, second gauge is arranged on the downstream of the second bypass and the second circulating water line.

As further improvement of these options, first-class gauge, second gauge, the 3rd effusion meter and the 4th flow Meter is all ultrasonic flowmeter, and the outer diameter tube of the first bypass and the second bypass is the first circulating water line and the second circulating water pipe The 1/3 of road external diameter, the external diameter of the first circulating water line and the second circulating water line is identical, the first circulating water line, the second circulation Water lines, the first bypass are the most identical with wall thickness with the pipe material of the second bypass, and it is equal that the first control valve and second controls valve It it is autocontrol valve；First-class gauge, second gauge, the 3rd effusion meter, the 4th effusion meter, the first temperature point, second Temperature point, the 3rd temperature point and the 4th temperature point are all electrically connected with the DCS control system of steam turbine.

This utility model has the advantage that this utility model belongs to the individually low back pressure condenser of control and follows compared to existing technology Ring discharge, on high back pressure side condenser circulating water flow without impact；The computing formula provided by this utility model and survey Point and valve control system, so that low back pressure side condenser vacuum does not enter obstruction back pressure district, reduce thermal loss of steam turbine rate； Due to the impact of recirculated water bypass, high back pressure side condenser recirculated water inflow temperature relative reduction, indirectly reduce high back pressure side row Stripping temperature, thus reduce thermal loss of steam turbine rate.

Accompanying drawing explanation

Fig. 1 is this utility model schematic diagram.

Fig. 2 is this utility model implementing procedure figure.

Detailed description of the invention

Elaborating embodiment of the present utility model below, the present embodiment is being front with technical solutions of the utility model Put and implement, give detailed embodiment and concrete operating process, but protection domain of the present utility model does not limits In following embodiment.

Embodiment 1

A kind of double pressure condenser optimized operating device, including high back pressure condenser 2, low back pressure condenser 1 and circulation Water lines, circulating water line is divided into the first circulating water line 11 and the second circulating water line 12, the first circulating water line 11 and Two-cycle pipeline 12 all flows to high back pressure condenser 2 from low back pressure condenser 1, it is characterised in that: on the first circulation waterway Being provided with the first bypass, the first bypass cross-over connection, at the two ends of low back pressure condenser 1, is provided with second other on the second circulation waterway Road, the second bypass is also connected across the two ends of low back pressure condenser 1, and the first bypass is provided with the second control valve 41, and second is other The second control valve 42 it is provided with on road.When, in unit operation, low back pressure side condenser vacuum enters after blocking back pressure district, this reality It is to adjust low back pressure side condenser circulating water flow by the novel middle purpose arranging bypath system, thus rises height back pressure side condensing Device recirculated water temperature rise and end are poor, final liter height back pressure side exhaust temperature, make low back pressure side condenser vacuum not enter the obstruction back of the body Nip.

First circulating water line 11 is provided with the first temperature point 21, the second circulating water line 12 is provided with Two temperature points 22, the first temperature point 21 is arranged on the outlet upstream of the first bypass, and the second temperature point 22 is arranged on The outlet upstream of two bypasses.

First circulating water line 11 is provided with the 3rd temperature point 23, the second circulating water line 12 is provided with Four temperature points 24, the 3rd temperature point 23 is arranged on the first bypass with the first circulating water line 11 point upstream, and Two temperature points 22 are arranged on the upstream of the second bypass and the second circulating water line 12.

First bypass is additionally provided with first-class gauge 31, the second bypass is provided with second gauge 32.

First circulating water line 11 is provided with the 3rd effusion meter 33, the second circulating water line 12 is provided with the 4th Effusion meter 34, the 3rd effusion meter 33 is arranged on the first bypass with the first circulating water line 11 point downstream, second flow Meter 32 is arranged on the downstream of the second bypass and the second circulating water line 12.

First-class gauge 31, second gauge the 32, the 3rd effusion meter 33 and the 4th effusion meter 34 are all ultrasonic flowmeters, The outer diameter tube of the first bypass and the second bypass is the first circulating water line 11 and the 1/3 of the second circulating water line 12 external diameter, the One circulating water line 11 is identical with the external diameter of the second circulating water line 12, first circulating water line the 11, second circulating water line 12, First bypass is the most identical with wall thickness with the pipe material of the second bypass, and the second control valve 41 and the second control valve 42 are all certainly Brake control valve door；First-class gauge 31, second gauge the 32, the 3rd effusion meter the 33, the 4th effusion meter the 34, first temperature point 21, the second temperature point the 22, the 3rd temperature point 23 and the 4th temperature point 24 all DCS control systems with steam turbine electrically connect Connect.

Embodiment 2

The operation method of a kind of above-mentioned double pressure condenser optimized operating device, it is characterised in that comprise the steps:

Step one, calculating steam turbine block back pressure value P_z,

P_z=f (G_ms)------formula (1)

Wherein G_msBeing steam turbine main steam flow, unit is kg/s, the DCS system of steam turbine obtain；

Step 2, calculating steam turbine block exhaust temperature t_z, block back pressure value according to the calculated steam turbine of step one P_z, calculating corresponding saturated-steam temperature according to IF-97 water vapour formula is i.e. that steam turbine blocks exhaust temperature t_z；Controlled by unit DCS The steam turbine main steam flow G that system processed obtains_ms, calculate correspondence according to formula (1) and block back pressure value, according to IF-97 water vapour Formula calculates corresponding saturated-steam temperature t_zAs long as guaranteeing that low back pressure side condenser exhaust temperature is saturated higher than blocking back pressure correspondence Vapor (steam) temperature t_z, low back pressure side back pressure of condenser is then not less than steam turbine and blocks back pressure.

Step 3, calculating bypass adjust front low back pressure side condenser duty Q_Cond1,

Q_Cond1=△ t₁×G_w1×C_p-------formula (2)

Wherein C_pIt is recirculated cooling water specific heat capacity, takes 4.2kJ/kg DEG C, △ t₁=(t₃₁-t₁+t₄₁-t₂)/2, t₁、t₂、t₃₁With t₄₁It is that bypass adjusts front first temperature point the 21, second temperature point the 22, the 3rd temperature point 23 and the 4th temperature point respectively The temperature of 24, G_w1It is circulating cooling water flow before bypass adjusts, G_w1=G₃₁+G₄₁-G₁₁-G₂₁, G₁₁、G₂₁、G₃₁And G₄₁Enter respectively Row bypass adjusts the data that front first-class gauge 31, second gauge the 32, the 3rd effusion meter 33 and the 4th effusion meter 34 are measured；

Step 4, calculating bypass adjust front condenser overall heat-transfer coefficient K₁,

δt₁=t_s1-(t_3-1+t_4-1)/2, t_s1It is low back pressure side condenser exhaust temperature before bypass adjusts, by unit DCS system System data acquisition, A is effective heat transfer area of condenser；

Step 5, correction condenser overall heat-transfer coefficient also calculate the circulating cooling water flow upper limit,

$(t_1+t_2)/2+\frac{Q_{Cond1}}{G_{w2}\×C_p}(1+\frac{1}{e^{\frac{K_{1}A}{G_{w1}\×C_p}}-1})=t_z+T$

Obtain after above-mentioned formula is deformed

G_w2Being the circulating cooling water flow upper limit, T is tolerance surplus, represents the low back pressure side condenser exhaust temperature set high In blocking the back pressure numerical value to answering saturated-steam temperature；

With low back pressure side condenser exhaust temperature higher than block back pressure to answer saturated-steam temperature T DEG C as separation, when Low back pressure side vacuum enters blocks back pressure region, is bypassed by recycling water formulation so that low back pressure side condenser exhaust temperature is high In blocking back pressure correspondence saturated-steam temperature T DEG C, it is contemplated that low back pressure side condenser recirculated water inflow temperature before and after bypass adjustment Constant, condenser heat transfer coefficient only needs to be corrected circulating water flow, and T preferred value is 2.

Step 6, bypass adjust, and regulation the second control valve 41 and second controls valve 42, makes G₁₂、G₂₂、G₃₂And G₄₂'s Meet

G_w2=G₃₂+G₄₂-G₁₂-G₂₂-----formula (5)

G₁₂、G₂₂、G₃₂And G₄₂It is by first-class gauge 31, second gauge the 32, the 3rd effusion meter after bypass adjusts respectively 33 and the 4th effusion meter 34 measure data.

DCS automatic control system controls valve 42 aperture by increasing by the second control valve 41 and second simultaneously, until entirely Open so that be G by low back pressure side condenser circulating cooling water flow_w2, adjustment terminates, and low back pressure side condenser vacuum is no longer located In blocking back pressure district.

After first bypass valve and the second valve opening, if owing to unit load reduces, or follow the change of pump operation pattern Increase to circulating water flow, or circulating water temperature raises so that low back pressure side condenser exhaust temperature is higher than blocking back pressure pair Answer saturated-steam temperature more than 2 DEG C, then repetition step 3 is to step 6, and reduces the second control valve 41 and second in step 6 Control valve 42 so that circulating water flow meets requirement, until fully closed.

These are only preferred embodiment of the present utility model, not in order to limit this utility model, all in this practicality Any amendment, equivalent and the improvement etc. made within novel spirit and principle, should be included in guarantor of the present utility model Within the scope of protecting.

Claims (6)

1. a double pressure condenser optimized operating device, including high back pressure condenser, low back pressure condenser and circulating water pipe Road, described circulating water line is divided into the first circulating water line and the second circulating water line, described first circulating water line and second Circulating water line all flows to high back pressure condenser from low back pressure condenser, it is characterised in that: it is provided with on the first circulation waterway First bypass, described first bypass cross-over connection, at the two ends of low back pressure condenser, is provided with the second bypass on the second circulation waterway, Described second bypass is also connected across the two ends of low back pressure condenser, and described first bypass is provided with the first control valve, described It is provided with the second control valve in second bypass.

2. a kind of double pressure condenser optimized operating device, it is characterised in that: at the first circulating water line On be provided with the first temperature point, the second circulating water line is provided with the second temperature point, described first temperature point sets Putting the outlet upstream in the first bypass, described second temperature point is arranged on the outlet upstream of the second bypass.

3. a kind of double pressure condenser optimized operating device, it is characterised in that: at the first circulating water line On be provided with the 3rd temperature point, the second circulating water line is provided with the 4th temperature point, described 3rd temperature point sets Putting the upstream with the first circulating water line point in the first bypass, described second temperature point is arranged on the second bypass and the The upstream of two-cycle pipeline.

4. a kind of double pressure condenser optimized operating device, it is characterised in that: also set in the first bypass It is equipped with first-class gauge, the second bypass is provided with second gauge.

5. a kind of double pressure condenser optimized operating device, it is characterised in that: at the first circulating water line On be provided with the 3rd effusion meter, the second circulating water line is provided with the 4th effusion meter, described 3rd effusion meter is arranged on The downstream with the first circulating water line point of one bypass, described second gauge is arranged on the second bypass and the second recirculated water The downstream of pipeline.

6. a kind of double pressure condenser optimized operating device, it is characterised in that: described first-class gauge, Second gauge, the 3rd effusion meter and the 4th effusion meter are all ultrasonic flowmeters, described first bypass and the pipe of the second bypass Road external diameter is the first circulating water line and the 1/3 of the second circulating water line external diameter, the first circulating water line and the second circulating water pipe The external diameter on road is identical, described first circulating water line, the second circulating water line, first bypass and second bypass pipe material and Wall thickness is the most identical, and described first control valve and second to control valve to be all autocontrol valve；Described first-class gauge, second Effusion meter, the 3rd effusion meter, the 4th effusion meter, the first temperature point, the second temperature point, the 3rd temperature point and the 4th temperature Measuring point is all electrically connected with the DCS control system of steam turbine.