CN103353770B - A kind of feedwater low content oxygenation accuracy control method and control system - Google Patents
A kind of feedwater low content oxygenation accuracy control method and control system Download PDFInfo
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- CN103353770B CN103353770B CN201310258236.0A CN201310258236A CN103353770B CN 103353770 B CN103353770 B CN 103353770B CN 201310258236 A CN201310258236 A CN 201310258236A CN 103353770 B CN103353770 B CN 103353770B
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Abstract
A kind of feedwater low content oxygenation accuracy control method and control system, the method is: in oxygen-eliminating device falls in export pipe, add rich oxygen containing demineralized water, controlling the addition of demineralized water by feedwater flow signal is 1/1000 ~ 2/1000 of feedwater flow, controls economizer entrance maintain 5 ~ 15 μ g/L to content of oxygen dissolved in water and saturated vapour dissolved oxygen content is less than 3 μ g/kg by feedwater dissolved oxygen DO signal and saturated vapour dissolved oxygen DO signal; Its system is: falling in export between pipe at solidifying water supply tank and oxygen-eliminating device is connected with a pipeline, pipeline is disposed with gate valve, desalination water pump, the first stop valve, the second stop valve, flowmeter, the 3rd stop valve, demineralized water flow control valve, reverse checkvalve and the 4th stop valve, is connected with PLC control cabinet with demineralized water flow control valve and flowmeter; Control method of the present invention and system can guarantee that superheated vapor, reheated steam are oxygen-free; Both prevented high-pressure feed water system from FAC occurring, the accident that after avoiding again feedwater high concentration oxygen, steam through-flow system scale spallation causes.
Description
Technical field
The present invention relates to thermal power plant's water-chemical regime control technology field, be specifically related to a kind of feedwater low content oxygenation accuracy control method and control system.
Background technology
Existing Feedwater Oxygenated Treatment adds oxygen to the oxygen-eliminating device pipe that falls in export, control economizer entrance feedwater dissolved oxygen DO at 30 ~ 150 μ g/L, the fluctuating range of feedwater oxygen content is very large, basic is that sinusoidal fashion fluctuates widely, although each manufacturer also carries out a large amount of research work in reduction oxygen content fluctuating range, at present fluctuating range minimum also at 50 more than μ g/L.Cause the large basic reason of feedwater oxygen content fluctuating range to be that the compressibility of gas is large, and the pressure of addition point changes along with the change of unit load.Control system adjusts the aperture of solenoid valve by the feedwater dissolved oxygen DO signal auxiliary feedwater flow signal fed back, because gas flow is very little, approximately per hour only have a few liter, for 300MW unit, oxygen flow often changes 1L/h, feedwater dissolved oxygen DO will be caused to change 15 more than μ g/L, therefore, feedwater oxygen content cannot be realized and accurately control among a small circle.
Because existing feed water oxygenation technology feedwater oxygen content is higher, the dissolved oxygen DO of 30 more than μ g/kg is generally had in steam, this can cause the superheater of some units, reheater oxide scale growth speed to accelerate, and finally causes coming off blocking and the overtemperature tube burst accident that causes because of oxide skin.Therefore, current many units adopt AVT (O) weak oxide Water purification technology, namely in feedwater, oxygen is not added, but export remaining micro amount of oxygen by oxygen-eliminating device, maintain more weak oxidisability operating mode, General Requirements feedwater dissolved oxygen DO is less than 10 μ g/L, but because the oxygen scavenging ability of oxygen-eliminating device is fine, general oxygen-eliminating device outlet feedwater dissolved oxygen content is at 2 below μ g/L, economizer entrance feedwater dissolved oxygen content is 0 μ g/L substantially, that is, dissolved oxygen DO in feedwater has been consumed, oxygen content very little, be not enough to meet the oxygen amount of repairing the damaged needs of passivating film, therefore, more weak to the inhibiting effect of high-pressure feed water system FAC.In order to make there are enough oxygen contents in feedwater, also need to add a small amount of oxygen again in feedwater.But oxygen content again can not be rich too many, otherwise dissolved oxygen DO that can be remaining more in superheated vapor, the superheater to some units, reheater oxide skin are had an impact.Therefore, a kind of oxygenation technology that can meet low content dissolved oxygen DO and accurately control is needed.
Summary of the invention
In order to solve above-mentioned prior art Problems existing, the object of the present invention is to provide a kind of feedwater low content oxygenation accuracy control method and control system, guarantee that saturated vapour dissolved oxygen content is less than 3 μ g/kg, ensure that superheated vapor, reheated steam are oxygen-free, can either prevent high-pressure feed water system FAC from occurring, after can effectively preventing feed water oxygenation again, steam through-flow system oxide skin increases the superheater tubes burst accident of peeling off initiation.
For reaching above object, the present invention adopts following technical scheme:
A kind of feedwater low content oxygenation accuracy control method, rich oxygen containing demineralized water is added in the oxygen-eliminating device of Power Plant Water Vapor system falls in export pipe, controlling the addition of demineralized water by feedwater flow signal is 1/1000 ~ 2/1000 of feedwater flow, maintains economizer entrance maintain 5 ~ 15 μ g/L to content of oxygen dissolved in water and saturated vapour dissolved oxygen content is less than 3 μ g/kg by feedwater dissolved oxygen DO signal and saturated vapour dissolved oxygen DO signal.
Realize the feedwater low content oxygenation accuracy-control system of method described above, coagulate water supply tank and oxygen-eliminating device in power plant to fall in export between pipe and be connected with a pipeline, this pipeline is disposed with gate valve 1, desalination water pump 7, first stop valve 2, second stop valve 3, flowmeter 10, the 3rd stop valve 4, demineralized water flow control valve 9, reverse checkvalve 5 and the 4th stop valve 6, is connected with PLC control cabinet 8 with demineralized water flow control valve 9 and flowmeter 10.
Compared to the prior art, tool has the following advantages in the present invention:
1, the present invention controls the addition of demineralized water by feedwater flow signal, carries out trace accurately control oxygenation to feedwater, accurately can control at 15 below μ g/L by feedwater oxygen content, guarantee that superheated vapor, reheated steam are oxygen-free.Therefore, both can prevent high-pressure feed water system from FAC occurring, the accident that after effectively can avoiding again feedwater high concentration oxygen, steam through-flow system scale spallation causes;
2, equipment investment is little, and the automatic aeration device price of current a set of gas generally more than 300,000 yuan, and needs to occupy 20m
2the space of left and right; Adopt this technology, only need increase by 2 (1 is standby with 1) flows to be no more than the concrete rated flow of 10t/h(and to determine according to unit size) desalination water pump, the stainless steel pipeline of 100m ~ 200m, 1 gate valve, 1 reverse checkvalve, 4 stop valves, 1 flowmeter, 1 flow control valve, 1 PLC control cabinet, cost is greatly about 150,000 yuan;
3, do not have dosing cost, natively will supplement demineralized water in boiler when unit normally runs, position covers Condenser's Hot Well, and sub-fraction demineralized water is just directly covered oxygen-eliminating device and to fall in export pipe by the present invention, therefore, dosing cost does not occur.Feedwater Oxygenated Treatment general in the world adds oxygen in oxygen-eliminating device falls in export pipe at present, and that generally buy is steel bottle oxugen (40L), and the oxygen consumption of 1 year of a 600MW unit is approximately 400 bottles, and cost is approximately 50,000 yuan;
4, do not have operation expense, when adding oxygen, need operations staff to make regular check on welding bottle pressure, change welding bottle, corresponding labour cost occur, and there is not operating labour cost in the present invention;
5, there is not safety problem, there is safety factor in high-pressure oxygen cylinder, but after adopting demineralized water, just there is not the safety problem of this respect.
Accompanying drawing explanation
Accompanying drawing is Control system architecture schematic diagram of the present invention.
Embodiment
Below in conjunction with drawings and the specific embodiments, the present invention is described in further detail.
The present invention's one feedwater low content oxygenation accuracy control method, rich oxygen containing demineralized water is added in power plant's oxygen-eliminating device falls in export pipe, controlling the addition of demineralized water by feedwater flow signal is 1.5/1000 of feedwater flow, controls economizer entrance maintain 5 ~ 15 μ g/L to content of oxygen dissolved in water and saturated vapour dissolved oxygen content is less than 3 μ g/kg by feedwater dissolved oxygen DO signal and saturated vapour dissolved oxygen DO signal.
Realize the feedwater low content oxygenation accuracy-control system of method described above, coagulate water supply tank and oxygen-eliminating device in power plant to fall in export between pipe and be connected with a pipeline, this pipeline is disposed with gate valve 1, desalination water pump 7, first stop valve 2, second stop valve 3, flowmeter 10, the 3rd stop valve 4, demineralized water flow control valve 9, reverse checkvalve 5 and the 4th stop valve 6, is connected with PLC control cabinet 8 with demineralized water flow control valve 9 and flowmeter 10.
When unit normally runs preparation feed water oxygenation, open gate valve 1, first stop valve 2, second stop valve 3, 3rd stop valve 4, reverse checkvalve 5 and the 4th stop valve 6, and start desalination water pump 7, PLC control cabinet 8 regulates demineralized water flow control valve 9 automatically according to feedwater flow signal, the demineralized water flow that flowmeter 10 is shown is 1/1000 ~ 2/1000 of feedwater flow, and according to feedwater dissolved oxygen DO signal and saturated vapour dissolved oxygen DO signal, demineralized water flow is adjusted again further by adjustment demineralized water flow control valve 9, feedwater dissolved oxygen content is made to maintain within the scope of 5 ~ 15 μ g/L, and guarantee that saturated vapour dissolved oxygen content is less than 3 μ g/kg.When stopping using when unit or do not need oxygenation due to other reasons, only need to stop desalination water pump 7, and closing gate valve 1, first stop valve 2, second stop valve 3, the 3rd stop valve 4, reverse checkvalve 5 and the 4th stop valve 6.
Claims (1)
1. a feedwater low content oxygenation accuracy control method, it is characterized in that: in the oxygen-eliminating device of Power Plant Water Vapor system falls in export pipe, add rich oxygen containing demineralized water, controlling the addition of demineralized water by feedwater flow signal is 1/1000 ~ 2/1000 of feedwater flow, controls economizer entrance maintain 5 ~ 15 μ g/L to content of oxygen dissolved in water and saturated vapour dissolved oxygen content is less than 3 μ g/kg by feedwater dissolved oxygen DO signal and saturated vapour dissolved oxygen DO signal.
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103880230B (en) * | 2014-03-26 | 2015-04-08 | 西安热工研究院有限公司 | Segmental oxidation treatment system and treatment method of thermodynamic system of novel coal-fired power plant |
| CN107621433B (en) * | 2017-09-08 | 2024-05-31 | 北京大学 | Device for regulating and controlling saturation of dissolved gas in liquid |
| CN110195855A (en) * | 2019-06-27 | 2019-09-03 | 中电华创(苏州)电力技术研究有限公司 | A kind of heat power plant boiler feed water oxygenation equipment |
| CN111552225A (en) * | 2020-04-28 | 2020-08-18 | 润电能源科学技术有限公司 | System and method for adjusting oxygen addition amount of boiler feed water |
| CN113149119A (en) * | 2021-03-10 | 2021-07-23 | 华电电力科学研究院有限公司 | Accurate oxygenation control system of thermal power factory condensate water |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4394261A (en) * | 1982-03-05 | 1983-07-19 | Texaco Inc. | System for controlling clarification of boiler feed water and the like |
| EP1328336B1 (en) * | 2000-09-27 | 2005-01-12 | Geir Corporation | Apparatus and method for increasing oxygen levels in a liquid |
| CN101851020A (en) * | 2010-04-29 | 2010-10-06 | 浙江省电力试验研究院 | DC boiler feed water selective oxidation treatment process |
| CN102997215A (en) * | 2012-06-14 | 2013-03-27 | 深圳市广前电力有限公司 | Quick start method and system of combined cycle unit |
| CN203311267U (en) * | 2013-06-25 | 2013-11-27 | 西安热工研究院有限公司 | Accurate control system for adding low-content oxygen to water supply |
-
2013
- 2013-06-25 CN CN201310258236.0A patent/CN103353770B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4394261A (en) * | 1982-03-05 | 1983-07-19 | Texaco Inc. | System for controlling clarification of boiler feed water and the like |
| EP1328336B1 (en) * | 2000-09-27 | 2005-01-12 | Geir Corporation | Apparatus and method for increasing oxygen levels in a liquid |
| CN101851020A (en) * | 2010-04-29 | 2010-10-06 | 浙江省电力试验研究院 | DC boiler feed water selective oxidation treatment process |
| CN102997215A (en) * | 2012-06-14 | 2013-03-27 | 深圳市广前电力有限公司 | Quick start method and system of combined cycle unit |
| CN203311267U (en) * | 2013-06-25 | 2013-11-27 | 西安热工研究院有限公司 | Accurate control system for adding low-content oxygen to water supply |
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Effective date of registration: 20161027 Address after: 710075 Shaanxi high tech District of Xi'an city high road Torch Hotel B Patentee after: XI'AN XIRE POWER STATION CHEMICAL SCIENCE & TECHNOLOGY CO., LTD. Address before: 710032 Xingqing Road, Shaanxi, China, No. 136, No. Patentee before: Xi'an Thermal Power Research Institute Co., Ltd. |
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