CN103307446B - Energy-saving method for stable flow water system - Google Patents
Energy-saving method for stable flow water system Download PDFInfo
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- CN103307446B CN103307446B CN201310201371.1A CN201310201371A CN103307446B CN 103307446 B CN103307446 B CN 103307446B CN 201310201371 A CN201310201371 A CN 201310201371A CN 103307446 B CN103307446 B CN 103307446B
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Abstract
The invention discloses an energy-saving method for a stable flow water system, which is characterized by comprising the following steps: firstly, measuring the pipe network resistance loss of the conventional water system; secondly, rectifying and reforming the water system pipe network of the conventional system; thirdly, measuring the water pump lift of the rectified water system; and fourthly, obtaining the optimal water pump suitable for the water system according to characteristics of the water system pipe network, hydrodynamic equations and a water pump working efficiency curve. According to the invention, the energy-saving method for the water system can be easily realized, the power consumption of the water system can be greatly saved through the adoption of the method, the energy-saving effect is remarkable, the selected new water pump can meet the requirement of the current water system, further reserves the follow-up expansion space, so that the design and manufacture cost of the water system is reduced.
Description
Technical field
The invention belongs to water conveying or the circulatory system in the fields such as cooling, circulation, feedwater, relate to a kind of power-economizing method of regime flow water system.
Background technique
Water conveying or the circulatory system are widely used in the fields such as cooling, circulation, feedwater, and its power consumption is huge, reaches 20% of world's electric quantity consumption.In water conveying or the circulatory system, there is water pump in a large number and mate irrational problem with system pipe network, cause great energy waste.
The energy consumption mainly water pump generation of water system.In the engineering of reality, the conventional design of water system and pump selection usually press the most unfavorable processing condition design and coupling, and in order to unilateral pursuit safety, under the most unfavorable processing condition, generally there is the surplus of 20% ~ 30%, and each water pump has an efficiency curve, only most effective under the flow and lift of amount, this just makes the type selecting of water pump to be in poor efficiency, high power consumption state, wastes energy greatly.
Because water system has larger surplus, people run frequently by closed portion valve opening, and the aperture of a lot of system valve only has 30% ~ 50%.Along with the progress of science and technology, have recently emerged a valve wide open, frequency conversion is adopted to regulate the method for pump motor rotating speed energy-conservation, fractional energy savings is 10% ~ 50%, but simultaneously because rotating speed reduces, flow declines, the actual operating efficiency of water pump will decline, and the power consumption 3% ~ 5% of frequency conversion own, therefore adopt single energy-saving and frequency-variable scheme, system energy consumption is still higher.Simultaneously because many one is run link, the stability of system declines to some extent, and frequency variator is expensive, so be badly in need of seeking the more suitably energy-conservation method for correcting error of one.
Summary of the invention
The technical problem of all solutions of the present invention is to provide a kind of power-economizing method of regime flow water system, profit realizes most energy-saving run to the conveying of water and the circulatory system in this way, solve water pump and mate irrational problem with system pipe network, by analyzing and rectifying and improving water system, the best selecting type scheme of water pump is provided, water system is consumed energy minimum, improve system works efficiency, reduce the design and manufacture cost of water system.
The technical solution of invention is as follows:
A power-economizing method for regime flow water system, comprises the following steps:
Step 1: the resistance of pipe system loss calculating existing water system;
1) water temperature T of water pump output and the operate power P of pump motor is measured
power, measure the hydraulic pressure P of pump intake and water outlet
1 hydraulic pressure, P
2 hydraulic pressure, flow rate of liquid V
1, V
2and pump intake and water outlet water flow Q
1and Q
2;
2) the height difference △ Z of the apical position of face, pond and pump outlet in water system is measured;
3) according to system-head curve in water system, look into ζ in plumbing handbook, calculate pipe network drag losses △ h: △ h=ζ V
2/ 2g, wherein g is gravity accleration, and unit is m/s
2, V is water velocity in pipe network,
unit is that m/s, ζ refer to resistance coefficient;
Step 2: the resistance of pipe system loss recorded according to step 1 detects existing water system pipe network and keeps in repair, and concrete operation step is as follows:
1) the pump intake place water flow Q of water system is detected
1with the water flow Q of water system pipe network node water outlet
2if both differ by more than 3%, then run in decision-making system pipe network, emit, leak and dripping phenomenon serious, check successively from water inlet node to water system pipe network node water outlet, the node that there is this phenomenon repaired;
2) detect the internal resistance r of exchanger assembly in water system, if checkout value exceedes the rating value that nameplate marks, then judge that exchanger assembly work is abnormal, keeps in repair it;
3) regulate water pump valve aperture to 90% ~ 100%, if observe plugged filter, then judge that filter can not normally work, to its cleaning or need change;
Step 3: to the water system after rectification, repeat the measurement in step 1, obtain rectifying and improving water pump output water temperature T ', the operate power P of pump motor in rear water system
power', the hydraulic pressure P of pump intake and water outlet
1 hydraulic pressure', P
2 hydraulic pressure', flow rate of liquid V
1', V
2' and pump intake and water outlet water flow Q
1', Q
2', in water system, the height difference Δ Z ' of the apical position of face, pond and pump outlet, makes p
2=P
2 hydraulic pressure', p
1=P
1 hydraulic pressure', v
2=V
2', v
1=V
1' z
2-z
1=Δ Z ', tries to achieve the pump head H of the rear water system of rectification:
In formula: p
2, p
1the mouth of a river, water inlet hydraulic pressure is pumped in water system after being respectively rectification;
V
2, v
1the flow velocity of the mouth of a river, water inlet liquid is pumped in water system after being respectively rectification;
Z
2, z
1the mouth of a river, water intake pressure meter device is pumped in water system to the distance of optional measurement datum after being respectively rectification;
Step 4: utilize H, Q of obtaining from step 3
2' and Δ Z ', make Q=Q
2', Δ Z=Δ Z ', according to hydrodynamic equations H=KQ
2+ △ Z tries to achieve the K of the rear water system of rectification, wherein, Q is water system power unit water outlet water flow, and K is water system characteristic constant, draw the hydraulic pipeline characteristic curve of water system after rectification, according to the water flow Q of the most high workload efficiency in the efficiency curve of water pump
i, hydraulic pipeline characteristic curve is found out corresponding pump head, determines optimal working point k;
Step 5: the H corresponding according to optimal working point k
k, Q
iwith conveying water temperature T ', chooses and reach lift needed for water system and water flow, and original water pump replaced by the highest water pump of working efficiency.
In described step 1, the method for measurement of the operate power of pump motor comprises two kinds: 1) utilize wattmeter directly to measure; 2) measure its operating voltage U, electric current I, and obtain power factor from nameplate
utilize
calculate.
In described step 1, use if there is the parallel connection of two or more water pump in water system, then need to measure each pump intake and water outlet hydraulic pressure P1
pressure, P2
pressure, flow rate of liquid V1, V2, using maximum pump head as the lift of system.
In described step 2, to the detection of Nodes water flow, also comprise the detection of the water flow of parts and pipeline junction in whole system, differ by more than pipeline in the node of 3% before and after carrying out measuring to water flow or parts keep in repair.
Beneficial effect
The invention provides a kind of power-economizing method of regime flow water system, adopt method provided by the invention by analyzing the working condition of existing water system and rectify and improve, for it chooses suitable new water pump again, water system can be made inefficient, the operating mode of high energy consumption is improved or eliminates, thus improve water system working efficiency, and it is more steady to make pump motor run, heating, vibrations, noise, the phenomenons such as cavitation erosion are effectively suppressed, solve water pump and mate irrational problem with system pipe network, contrast experiment's data, result shows, this method is used can significantly to save water system power consumption, energy-saving effect is remarkable, the new water pump selected not only can meet the demand of current water system, but also remain later extending space, reduce the design and manufacture cost of water system.
Accompanying drawing explanation
Fig. 1 blast furnace water at atmospheric pressure system architecture diagram;
Fig. 2 characteristic curve of pump and hydraulic pipeline performance diagram.
Embodiment
Below with reference to the drawings and specific embodiments, the present invention is described in further details:
With the technological transformation of certain steel mill water-supply plant 19# water station SP energy saving of system, the present invention is described in further detail by reference to the accompanying drawings.
SP system is soft water system, and in the present system, the backwater after user uses is cooled by plate type heat exchanger, then enters pump entrance and again circulates.
Native system, for 4# blast furnace cooling stave and furnace bottom cooling, comprises 3 water pumps, and 2 normally use, and 1 for subsequent use.Every cover system design discharge 5200m
3/ h.This system is furnished with 3 water pumps altogether.
1. obtain relevant parameter, record the resistance of pipe system loss of existing water system;
(1) the nameplate parameter of water pump and motor can obtain from on-the-spot nameplate, can check in, Type of pump 600S47, water pump rated flow 2600m if nameplate is unclear from equipment raw data
3/ h, rated head 52m.Necessary electromotor is YKK5003-6/560kW/10kV/41.2A/990rpm;
(2) by the water temperature that thermometer or other apparatus measures water pump are carried, if judge, temperature can accident at 0 ~ 70 DEG C.
(3) the operate power P of pump motor
poweradopt and measure electric current I, voltage U and power factor
by formulae discovery:
obtain from nameplate, motor power factor
(4) adopt pressure gauge or vacuum gauge to carry out piezometry to selected water system node, adopt ultrasonic flowmeter to measure flow, flow velocity;
A. respectively to water-in and water-out node a and b of 2 that run in water system water pumps in parallel, water pump inlet and outlet pressure P1, P2 is measured.
B. choose b point in water system, record pump capacity Q
1=2555m
3/ h, Q
2=2600m
3/ h, chooses e point, records water system end flow ∑ Q=5110m
3/ h.
C. choose water-in and water-out node a and b of water pump in water system, measure water pump inlet/outlet water flow velocity V1=2.5114m/s, V2=3.6164m/s respectively, because the flow difference at two water pump inlet/outlet places is less than 45m
3/ h, is converted to m/s, and difference is 0.0125, affects very little, using both mean value as the inlet/outlet water flow velocity of water pump in water system.
D. the height difference △ Z=18 of pond 1 and cooling unit 4 in water system is measured, unit: m.
E. because system cools wall and furnace bottom backwater valve aperture are about 30 °, and house steward there are two butterfly valve valve openings about 40 °.According to system-head curve, look into plumbing handbook table, drag evaluation is carried out to valve, obtain the drag losses △ h=25m at outlet valve place;
Wherein, H-lift, m; The pressure of P1, P2-pump import and export liquid, Pa; V1, V2-fluid at the water flow velocity at pump inlet/outlet place, m/s; ρ-fluid density, kg/m
3; G-gravity accleration, m/s
2.
Table 1 systematic survey parameter
Calculate the active power of pump group, upper table electric current is substituted into the power consumption (i.e. active power) that rating formula can draw pump group: P
sp1=502.2, P
sp2=501.
2. pair water system pipe network is rectified and improved, and overcomes the unfavorable factor existed in pipe network;
(1) because system return valve drag losses is 25m, the increase of the flow system flow of the aging of equipment after considering, is transferred to more than 90% or standard-sized sheet by this backwater valve aperture, saves the valve losses of about 14m.
3. remeasure the operate power of pump motor, suitably choose node a, b and e of water system, remeasure the pressure of Nodes, water flow, survey data is as shown in table 2, recalculate water pump total head, utilize the water pump total head and water flow that again obtain to draw hydraulic pipeline characteristic curve.
Systematic survey parameter after table 2 rectification
4. calculate the water pump total head H after rectification by step 3, pump outlet flow Q and △ Z, recalculates K, then according to water system hydraulic pipeline characteristic equation H=KQ
2+ △ Z, as shown in Figure 2, is hydraulic pipeline characteristic curve by the parabola of water pump operation point.The k point met on the hydraulic pipeline characteristic curve of water system requirement flow and pressure is optimum condition operating point.
5. the flow corresponding to optimum condition operating point, lift and conveying water temperature choose suitable best water pump, ensure that optimum condition operating point is in the efficient section of pump's performance curre.By separate unit pump capacity 2600m
3/ h, lift H=40m select high effective pump to replace original pump.So namely, production can be met.Leave again later adjustment space, the existing flow of flow-rate ratio has the surplus of 1.3 times.
As shown in Figure 2: X curve is the characteristic curve of pump of former installation; X ' curve is high efficiency energy saving pump performance curve, and G curve is system pipe network hydraulic characteristic curve, and η curve is the Pump Efficiency Curve of former installation, and η ' curve is the efficiency curve of energy-efficient water pump.Former operating point for design i: flow Qi, lift Hi; Operating point b: the flow Q of actual measurement
j, lift H
j.
As shown in Figure 2: water pump is originally in high flow capacity, high-lift, inefficient, high power consumption is run, and by detecting relevant parameter, is optimized system, and obtain system pipe network hydraulic characteristic curve by actual measurement parameter, the flow on curve is design discharge Q
ik point (Q
i, H
k) be optimum condition operating point, be chosen at optimum condition operating point and run, most effective water pump, is high efficiency energy saving pump, and the operating point of this pump is flow Q
i, lift H
k, efficiency eta
k;
As shown in Figure 2: by 0, H
j, j, Q
jthe region surrounded is the operation energy consumption of water pump in original water system, 0, H
k, k, Q
ithe region surrounded is the operation energy consumption of water pump in the water system after adopting process of the present invention.The difference of two region areas is the energy consumption that the present invention saves.Original water pump replaced by the best water pump choosing k point corresponding.
Energy consumption comparison after table 3 technological transformation and before technological transformation
As can be seen from the above table, can be made by the present invention that water system is inefficient, the operating mode of high energy consumption is improved or eliminates, improve system effectiveness, and it is more steady to make pump motor run, the phenomenons such as heating, vibrations, noise, cavitation erosion are effectively suppressed, solve water pump and mate irrational problem with system pipe network, power saving rate reaches 28.4%, and energy-saving effect is remarkable.
Claims (4)
1. a power-economizing method for regime flow water system, is characterized in that, comprises the following steps:
Step 1: the resistance of pipe system loss calculating existing water system;
1) water temperature T of water pump output and the operate power P of pump motor is measured
power, measure the hydraulic pressure P of pump intake and water outlet
1 hydraulic pressure, P
2 hydraulic pressure, flow rate of liquid V
1, V
2and pump intake and water outlet water flow Q
1and Q
2;
2) the height difference △ Z of the apical position of face, pond and pump outlet in water system is measured;
3) according to system-head curve in water system, look into ζ in plumbing handbook, calculate pipe network drag losses △ h: △ h=ζ V
2/ 2g, wherein g is gravity accleration, and unit is m/s
2, V is water velocity in pipe network,
unit is that m/s, ζ refer to resistance coefficient;
Step 2: the resistance of pipe system loss recorded according to step 1 detects existing water system pipe network and keeps in repair, and concrete operation step is as follows:
1) the pump intake place water flow Q of water system is detected
1with the water flow Q of the water outlet of water system pipe network node
2if both differ by more than 3%, then run in decision-making system pipe network, emit, leak and dripping phenomenon serious, check successively from water inlet node to water system pipe network node water outlet, the node that there is this phenomenon repaired;
2) detect the internal resistance r of exchanger assembly in water system, if checkout value exceedes the rating value that nameplate marks, then judge that exchanger assembly work is abnormal, keeps in repair it;
3) regulate water pump valve aperture to 90% ~ 100%, if observe plugged filter, then judge that filter can not normally work, to its cleaning or need change;
Step 3: to the water system after rectification, repeat the measurement in step 1, obtain rectifying and improving water pump output water temperature T ', the operate power P of pump motor in rear water system
power', the hydraulic pressure P of pump intake and water outlet
1 hydraulic pressure', P
2 hydraulic pressure', flow rate of liquid V
1', V
2' and pump intake and water outlet water flow Q
1', Q
2', in water system, the height difference Δ Z ' of the apical position of face, pond and pump outlet, makes p
2=P
2 hydraulic pressure', p
1=P
1 hydraulic pressure', v
2=V
2', v
1=V
1' z
2-z
1=Δ Z ', tries to achieve the pump head H of the rear water system of rectification:
In formula: p
2, p
1the mouth of a river, water inlet hydraulic pressure is pumped in water system after being respectively rectification;
V
2, v
1the flow velocity of the mouth of a river, water inlet liquid is pumped in water system after being respectively rectification;
Z
2, z
1the mouth of a river, water intake pressure meter device is pumped in water system to the distance of optional measurement datum after being respectively rectification;
Step 4: utilize H, Q of obtaining from step 3
2' and Δ Z ', make Q=Q
2', Δ Z=Δ Z ', according to hydrodynamic equations H=KQ
2+ △ Z tries to achieve the K of the rear water system of rectification, wherein, Q is water system power unit water outlet water flow, and K is water system characteristic constant, draw the hydraulic pipeline characteristic curve of water system after rectification, according to the water flow Q of the most high workload efficiency in the efficiency curve of water pump
i, hydraulic pipeline characteristic curve is found out corresponding pump head, determines optimal working point k;
Step 5: the H corresponding according to optimal working point k
k, Q
iwith conveying water temperature T ', chooses and reach lift needed for water system and water flow, and original water pump replaced by the highest water pump of working efficiency.
2. the power-economizing method of regime flow water system according to claim 1, is characterized in that, in described step 1, the method for measurement of the operate power of pump motor comprises two kinds: 1) utilize wattmeter directly to measure; 2) measure its operating voltage U, electric current I, and obtain power factor from nameplate
utilize
calculate.
3. the power-economizing method of regime flow water system according to claim 1, is characterized in that, in described step 1, uses, then need to measure each pump intake and water outlet hydraulic pressure P1 if there is the parallel connection of two or more water pump in water system
pressure, P2
pressure, flow rate of liquid V1, V2, using maximum pump head as the lift of system.
4. the power-economizing method of regime flow water system according to claim 1, it is characterized in that, in described step 2, to the detection of Nodes water flow, also comprise the detection of the water flow of parts and pipeline junction in whole system, differ by more than pipeline in the node of 3% before and after carrying out measuring to water flow or parts keep in repair.
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Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112580183B (en) * | 2019-09-30 | 2024-02-23 | 北京大学 | Real-time flow accurate control method for online learning water pump model |
| CN111287253B (en) * | 2020-02-28 | 2021-05-18 | 杭州永创环境科技有限公司 | Water supply system optimization method |
| CN114857498B (en) * | 2022-05-11 | 2024-03-22 | 长沙九洲鸿云网络科技有限公司 | Method for confirming resistance characteristics of water supply network |
| CN116167188B (en) * | 2023-04-19 | 2023-07-11 | 江苏华飞宇节能技术有限公司 | Circulating water energy-saving data processing method and system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101008475A (en) * | 2007-01-23 | 2007-08-01 | 范昌海 | Correction methods of online fluid system |
| JP2009192329A (en) * | 2008-02-13 | 2009-08-27 | Toshiba Corp | Water leakage diagnostic device and water leakage diagnostic method for water distribution pipe line |
| CN101666319A (en) * | 2009-09-29 | 2010-03-10 | 长沙翔鹅节能技术有限公司 | Energy saving method for circulating water system |
| CN102052293A (en) * | 2010-11-29 | 2011-05-11 | 湖南泰通电力科技有限公司 | Confirming method of lift needed by cooling circulating water system |
| CN102542120A (en) * | 2012-01-17 | 2012-07-04 | 浙江科维节能技术有限公司 | Method for designing energy-saving type circulating cooling water system |
-
2013
- 2013-05-27 CN CN201310201371.1A patent/CN103307446B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101008475A (en) * | 2007-01-23 | 2007-08-01 | 范昌海 | Correction methods of online fluid system |
| JP2009192329A (en) * | 2008-02-13 | 2009-08-27 | Toshiba Corp | Water leakage diagnostic device and water leakage diagnostic method for water distribution pipe line |
| CN101666319A (en) * | 2009-09-29 | 2010-03-10 | 长沙翔鹅节能技术有限公司 | Energy saving method for circulating water system |
| CN102052293A (en) * | 2010-11-29 | 2011-05-11 | 湖南泰通电力科技有限公司 | Confirming method of lift needed by cooling circulating water system |
| CN102542120A (en) * | 2012-01-17 | 2012-07-04 | 浙江科维节能技术有限公司 | Method for designing energy-saving type circulating cooling water system |
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Address after: 410116 Hunan province Changsha hi tech Development Zone, Lu Tin Road No. 28 Minmetals Lugu Science Park B2 building 501 room Patentee after: Hunan Taitong energy management Limited by Share Ltd Address before: 410116 Hunan province Changsha Yuhua District, Hunan Road No. 9, Longchamp Garden Hotel elegant building 21 floor Hunan Taitong Electric Power Technology Co Ltd Patentee before: Hunan Taitong Electric Power Science and Technology Co., Ltd. |