Background technology
Dissolved oxygen is considered to be in an important chemical index in the Power Plant Water Vapor circulatory monitoring.The chemical process that oiler feed is handled comprises reductibility processing (the Reducing All-VolatileTreatment that volatilizees entirely, AVT (R)), oxidisability processing (the Oxidizing All-VolatileTreatment that volatilizees entirely, AVT (O)) and oxygenation handle (Oxygenated Treatment, OT).The system that uses OT and AVT (O) is reliable in the world at present and operating performance water treatment system preferably.Under the condition of aerobic, the hole of Z 250 protective layer can be filled by the ferric oxide hydrate (FeOOH) of some low-solubilities or ferric oxide (Fe2O3).Sometimes ferric oxide even can cover whole Z 250 protective layer.Like this, the iron concentration in the feedwater just may reach minimum standard.For the oxygen concn in the feedwater, AVT (R) general requirement≤7ppb of system is low more good more; The OK range of OT system can be tens of to hundreds of ppb; And AVT (O) general requirement≤10ppb of system is limited on leaning on.
Feedwater AVT (O) mode is a kind of new oiler feed processing mode.This processing mode is carried out oxidisability to water feeding system and is handled by precisely adjusting economizer inlet ug/L magnitude trace oxygen.In the AVT of prior art (O) mode, condensed water and economizer are given the uncontrollable leakage of water-soluble oxygen from condenser, to exceeding the part of demand, regulate by adjusting deaerator exhaust; But if natural leak dissolved oxygen deficiency, the AVT of prior art (O) mode is not given consideration.Practice shows, progress with modern high pressure high temperature turbosets, most unit condenser tightness excellences, the nature dissolved oxygen is few, condensed water almost is in anaerobic state, the dissolved oxygen control method of the AVT of prior art (O) mode is powerless, can not guarantee best dissolved oxygen control, therefore needs a kind of corresponding oxygenating mode.
The OT mode of prior art has corresponding oxygenation method.Fig. 1 is the synoptic diagram that the oxygenation of prior art is handled.As shown in Figure 1, station boiler comprises (can also comprise low pressure heater, high pressure heater, water wall, superheater, reheater, gas-turbine etc., not shown in Fig. 1) such as condensate pump pump group 10, precision processing 11, deoxygenator 12, service pump 13, condensers 14.Condensate pump inlet oxygen table 15 is arranged in the ingress of condensate pump pump group 10, deoxygenator outlet oxygen table 16 is arranged in the exit of deoxygenator 12.First of OT mode adds the exit that oxygen point 17 is positioned at precision processing 11, and second adds the exit that oxygen point 18 is positioned at deoxygenator 12.Add oxygen point corresponding to MPa level system pressure, select the oxygenation system component of respective level parameter for use, feedwater is carried out 10
2Ug/L magnitude oxygenation.But the OT mode of prior art is in all inapplicable AVT (O) mode that maybe can not be used for of many aspects, for example, 1) the oxygenation point pressure is higher, the corresponding raising of system design installation requirement, and safety coefficient descends; 2) after the oxygenation point pressure improved, for the required micro-oxygen-adding amount of AVT (O) mode, volumetric flow rate was the order of magnitude and descends, and all brought obvious difficulty for selection, correction and the Flow-rate adjustment control of oxygenation system component; 3) be accurately to detect 2 oxygenations of control, need add first and second increases oxygen table and sampling spot thereof between oxygen point; 4) operating pressure that adds oxygen point is with the load noticeable change, and its pressure reduction variation tendency with the oxygenation system is just in time opposite with the required direction variation of oxygenation, unfavorable adjustment; 5) to promptly and accurately adjust oxygenation, need the complicated interlock TT﹠C system of design with load.
Summary of the invention
The technical problem that the present invention will solve provides a kind of water-supply oxygen supplementing device of station boiler, has higher security.
The invention provides a kind of water-supply oxygen supplementing device of station boiler, comprising: the measurement of oxygen content module is used to measure the dissolved oxygen content of ingress condensed water of the condensate pump pump group of station boiler; The oxygen that provides oxygenating required is provided oxygen source; The oxygen flow adjustment module is connected with oxygen source, can insert the ingress of condensate pump pump group, and the dissolved oxygen content that is used for exporting according to the measurement of oxygen content module is controlled the flow to the condensed water oxygenating.
According to an embodiment of oxygen supplementing device of the present invention, the oxygen source of described oxygen supplementing device comprises: oxygen cylinder is used to store oxygen; Oxygen pressure regulator is used to regulate the pressure from the Oxygen Flow of described oxygen cylinder output.Described oxygen flow adjustment module comprises: spinner-type flowmeter is used to measure the oxygen flow from oxygen source; The oxygen flow variable valve is used to regulate the oxygen flow from oxygen source; Oxygenating point segregaion valve links to each other with the ingress of the condensate pump pump group of described station boiler, is used for on/off oxygenating operation.
Further, above-mentioned oxygen flow variable valve is the oxygen flow motor-driven control valve.The measurement of oxygen content module comprises: condensate pump inlet oxygen table is used to measure the dissolved oxygen content of condensate pump ingress condensed water; Deoxygenator outlet oxygen table is used to measure the dissolved oxygen content of deoxygenator exit feedwater; The oxygenating controller is used for controlling described oxygen flow motor-driven control valve according to the dissolved oxygen content that the dissolved oxygen content and the described deoxygenator outlet oxygen table of the measurement of described condensate pump inlet oxygen table are measured.
The water-supply oxygen supplementing device of station boiler provided by the invention by the oxygenating point is reelected in the ingress of condensate pump pump group, is stable negative pressure, and total system is the normal pressure system, has high security.
The present invention also provides a kind of station boiler that comprises above-mentioned oxygen supplementing device.
Another technical problem that the present invention will solve provides a kind of water-supply oxygen supplementing method of station boiler, has higher security.
Oxygen replenishing method provided by the invention comprises: the dissolved oxygen content of measuring condensate pump inlet condensed water; Dissolved oxygen content in the condensate pump ingress according to condensate pump inlet condensed water carries out oxygenating to condensed water.
According to an embodiment of oxygen replenishing method of the present invention, this oxygen replenishing method also comprises: the dissolved oxygen content of measuring deoxygenator outlet feedwater.In the condensate pump ingress, condensed water is carried out oxygenating according to the dissolved oxygen content of condensate pump inlet condensed water and the dissolved oxygen content of deoxygenator outlet feedwater.
Further, this oxygen replenishing method also comprises: provide oxygen by oxygen cylinder, public oxygen system or oxygenerator, regulated the pressure of output oxygen by the atmosphere gas pressure-regulator; Regulate oxygen supplying flow by the oxygen flow variable valve.
The oxygen replenishing method of station boiler provided by the invention by the oxygenating point is selected in the condensate pump ingress, is stable negative pressure, has high security.
Embodiment
With reference to the accompanying drawings the present invention is described more fully, exemplary embodiment of the present invention wherein is described.In the accompanying drawings, identical label is indicated identical or similar element or assembly.
The present invention proposes a kind of new weak oxide processing (WOT) oxygenating mode.WOT oxygenating mode is followed two target upper limits of AVT (O) mode to the control of dissolved oxygen: condensed water dissolved oxygen≤30ug/L and deoxygenator outlet (or economizer inlet)≤10ug/L.Owing to above-mentioned two place's dissolved oxygens are too high corrosion risk is arranged all, thus oxygenating is formed following requirement: 1) at first control condensed water dissolved oxygen≤30ug/L, take precautions against corrosion risk; 2) deoxygenator outlet (or economizer inlet) should be controlled dissolved oxygen near upper limit 10ug/L, guarantees weak oxide treatment effect and conversion process as soon as possible.
Fig. 2 is the synoptic diagram of the oxygenating point of method and apparatus of the present invention.As shown in Figure 2,21 places are put in the oxygenating that the oxygenating point has been selected in before the condensate pump pump group 10, rather than first shown in Fig. 1 adds the position that oxygen point 17 and second adds oxygen point 18 places.
Fig. 3 is the block diagram of an embodiment of oxygen supplementing device of the present invention.As shown in Figure 3, the oxygen supplementing device 30 of station boiler of the present invention comprises oxygen source 31, oxygen flow adjustment module 32 and measurement of oxygen content module 33.Wherein, measurement of oxygen content module 33 links to each other with the ingress of condensate pump pump group, is used to measure the dissolved oxygen content of condensate pump pump group 10 ingress condensed water.Measurement of oxygen content module 33 can be a condensate pump inlet oxygen table.Oxygen source 31 is used to provide oxygen, can be oxygen cylinder, public oxygen system or oxygenerator.Oxygen flow adjustment module 32 links to each other with the inlet of oxygen source 31 with condensate pump pump group 10 respectively, is used for regulating oxygen supplying flow according to the dissolved oxygen content that measurement of oxygen content module 33 is measured.
According to another embodiment of oxygen supplementing device of the present invention, above-mentioned measurement of oxygen content module also is used to measure the dissolved oxygen content of station boiler economizer feedwater; Above-mentioned oxygen flow adjustment module is according to the dissolved oxygen content control of the condensed water dissolved oxygen content of the ingress of the condensate pump pump group of measurement of oxygen content module output and the economizer feedwater flow to the condensed water oxygenating.
Fig. 4 is the block diagram of another embodiment of oxygen supplementing device of the present invention.The water extraction pump pump group 10 of station boiler only is shown for the sake of brevity.As shown in Figure 4, the oxygen supplementing device 40 of station boiler of the present invention comprises oxygen cylinder 411, oxygen pressure regulator 412, rotor gauger 423, oxygen flow variable valve 422 and the oxygenating point segregaion valve 421 that connects successively.Oxygenating point segregaion valve links to each other with the inlet of condensate pump pump group 10.Oxygen supplementing device 40 also comprises condensate pump inlet oxygen table 43.Oxygen cylinder 411 and oxygen pressure regulator 412 are formed the indefiniteness example of oxygen source 42.Rotor gauger 423, oxygen flow variable valve 422 and oxygenating point segregaion valve 421 are formed the indefiniteness example of oxygen flow adjustment module 42.The oxygenating point is positioned at the female tube inlet of condensate pump pump group, is provided with oxygenating point segregaion valve 421.Utilize this oxygen supplementing device, can put segregaion valve 421 by oxygenating and carry out the oxygenating on/off, manually carry out Flow-rate adjustment by oxygen flow variable valve 422.When carrying out Flow-rate adjustment,, adjust oxygen flow variable valve 422 according to the oxygen flow shown in the spinner-type flowmeter 423 according to the oxygenating amount of the definite needs of condensate pump inlet oxygen table 43.For example, the scope of oxygen pressure regulator 412 is a normal pressure, such as between 0.05-0.5MP, is preferably the special-purpose voltate regulator of 0.1MPa, and spinner-type flowmeter 423 is a float-type minimum gas under meter.This oxygen supplementing device is applicable to the continous-stable oxygenating.
WOT mode of the present invention in the transformation stage, can export oxygen according to deoxygenator and represent number when carrying out oxygenating control, and control condensed water dissolved oxygen is taken precautions against corrosion risk by standard max (30ug/L) operation, and the fastest conversion rate is provided simultaneously; Stable operation stage after conversion can export oxygen according to deoxygenator and represent number, adjusts control condensed water dissolved oxygen content, keeps deoxygenator outlet dissolved oxygen at standard max scope (as 7-10ug/L).
The oxygenating point of above-mentioned oxygen supplementing device is selected on the preceding condensate pipe that flows of condensate pump stablizes the negative pressure place, selects the atmosphere gas pressure-regulator for use, and flow control valve is in the pressure-regulator downstream, makes its operating pressure and correcting state approaching; Above-mentioned design makes that pressure reduction keeps relative stability between SOS and condensed water, can not cause oxygen-adding amount and condensing water flow inverse change because of load variations; The work of under meter normal pressure, volumetric flow rate reaches 10
2The ml/min magnitude has enough accuracy and guarantees accurately regulation and control; The normal pressure system, safe.
According to another embodiment of oxygen supplementing device of the present invention, regulate the magnetic valve group with oxygen flow and come oxygen flow variable valve in the alternate figures 4.Oxygen flow is regulated the magnetic valve group between spinner-type flowmeter and oxygenating point segregaion valve.For example, be made up of the magnetic valve (K1, K2, K3) of three groups of flows through adjusting flow respectively in advance in proportion, ratio is K1: K2: K3=1 between the three: 2: 5, the oxygen supplying flow that realizes in proportion capable of being combined is than 0,1, and 2,3,5,6,7,8 (or 0%, 12.5%, 25%, 27.5%, 50%, 75%, 87.5%, 100%) 8 kinds of combinations.The on/off of oxygen and Flow-rate adjustment can manually be finished in a watchroom distant place, are applicable to according to condensing water flow, dissolved oxygen level to change distant place manual regulation.Those skilled in the art will appreciate that the oxygen supplying flow beguine can adopt other numerical value according to the needs of using.
Fig. 5 is the block diagram of another embodiment of oxygen supplementing device of the present invention.As shown in Figure 5, oxygen supplementing device 50 comprises oxygen cylinder 411, oxygen pressure regulator 412, rotor gauger 423, oxygen flow motor-driven control valve 522 and the oxygenating point segregaion valve 421 that connects successively.Oxygenating point segregaion valve 421 links to each other with the inlet of condensate pump pump group 10.Oxygen supplementing device 50 also comprises condensate pump inlet oxygen table 531, deoxygenator outlet oxygen table 532 and oxygenating controller 534.Condensate pump inlet oxygen table 531 is used to measure the dissolved oxygen amount of condensate pump pump inlet place condensed water, and exports to oxygenating controller 534.Deoxygenator outlet oxygen table 532 is used to measure the dissolved oxygen amount of deoxygenator exit feedwater, and exports to oxygenating controller 534.Oxygenating controller 534 is according to the input from condensate pump inlet oxygen table 531 and deoxygenator outlet oxygen table 532, determines the oxygenating amount that needs, and oxygenating amount is as required adjusted oxygen flow motor-driven control valve 522 automatically.In addition, oxygen supplementing device 50 can also comprise condensing water flow meter 533, is used to measure the data on flows at condensate pump pump group place, and this data on flows is exported to oxygenating controller 534.Oxygenating controller 534 is according to the input from condensate pump inlet oxygen table 531, deoxygenator outlet oxygen table 532 and condensing water flow meter 533, and definite oxygenating amount that needs is regulated oxygen flow motor-driven control valve 522.Those skilled in the art will appreciate that in some applications oxygen supplementing device 50 can not comprise spinner-type flowmeter 423; Perhaps use other oxygen source alternate standard oxygen cylinder 411 and oxygen pressure regulators 412.By oxygen supplementing device 50, the on/off of oxygen and Flow-rate adjustment are carried out by the parameter of setting automatically by oxygenating controller 534, and the control signal input is from the output of condensate pump inlet oxygen table 531, deoxygenator outlet oxygen table 532 and condensing water flow meter 533.Be applicable to that a distant place regulates automatically.
When WOT mode of the present invention is carried out oxygenating control, in the transformation stage, can export the dissolved oxygen data of oxygen table, the output of condensed water oxygen table and the data on flows of condensing water flow meter output according to deoxygenator, control condensed water dissolved oxygen is by standard max (30ug/L) operation, take precautions against corrosion risk, the fastest conversion rate is provided simultaneously; Stable operation stage after conversion, can export the dissolved oxygen data of oxygen table, the output of condensed water oxygen table and the data on flows of condensing water flow meter output according to deoxygenator, adjust control condensed water dissolved oxygen content, keep deoxygenator outlet dissolved oxygen at standard max scope (as 7-10ug/L).
Fig. 6 is the schema that carries out an example of oxygenating control according to oxygen supplementing device shown in Figure 5.
As shown in Figure 6, in step 602, gather O
EconomizeData.
In step 604, judge O
EconomizeWhether greater than 10 μ g/L, if, then continue performing step 610, otherwise, performing step 606 continued.
In step 606, input Q
Coagulate, set k, C
0, N
In step 608, regulate and control the oxygenating amount by following formula:
V
O2=(30-C
0, N) * Q
Coagulate* k (1).
In step 610, input O
Coagulate, Q
Coagulate, set k.
In step 612, regulate and control the oxygenating amount by following formula:
V
O2=(O
Coagulate-5) * Q
Coagulate* k (2).
In above-mentioned step, O
EconomizeBe economizer (deoxygenator outlet) dissolved oxygen meter reading, unit is μ g/L; O is condensed water dissolved oxygen meter reading with fixed attention, and unit is μ g/L; Q is condensing water flow with fixed attention, and unit is m3/h; K is O2 volumetric flow rate and a mass rate gain factor under 1 standard atmospheric pressure and the standard temperature (25 ℃); C0, N are condensed water dissolved oxygen amount baseline values, and unit is μ g/L, and it is the function of load N, get its history average and set.Above-mentioned steps 602 to 612 can circulate and carry out.
Fig. 7 is the schema of an embodiment of the oxygen replenishing method of station boiler of the present invention.
As shown in Figure 7, in step 702, measure the dissolved oxygen content of condensate pump inlet condensed water.For example, measure dissolved oxygen content by condensate pump inlet oxygen table.
In step 704,, condensed water is carried out the oxygenating operation according to the dissolved oxygen content of condensate pump inlet condensed water in the condensate pump ingress.According to the dissolved oxygen content of condensate pump inlet condensed water, and the target of the dissolved oxygen content that reaches of expectation, need to determine the amount of oxygenating, and make the condensed water dissolved oxygen be no more than the condensed water dissolved oxygen level of standard code.For example control oxygen flow, thereby regulate the oxygenating amount from oxygen source by the oxygen flow variable valve.Above-mentioned steps 702 to 704 can circulate and carry out.
According to an embodiment of oxygen replenishing method of the present invention, above-mentioned oxygenating point is selected on the preceding condensate pipe that flows of condensate pump stablizes the negative pressure place.Provide oxygen by standard oxygen gas cylinder, public oxygen system or oxygenerator as oxygen source, regulate the pressure of output oxygen by gas regulator.The gas regulator scope is a normal pressure, and scope is generally between 0.05-0.5MP.The oxygen flow variable valve is in the gas regulator downstream, makes its operating pressure and correcting state approaching.Above-mentioned design makes that pressure reduction keeps relative stability between SOS and condensed water, can not cause oxygen-adding amount and condensing water flow inverse change because of load variations.
Fig. 8 is the schema of another embodiment of the oxygen replenishing method of station boiler of the present invention.
As shown in Figure 8, in step 802, measure the dissolved oxygen content of condensate pump inlet condensed water by the oxygen table.
In step 804, measure the dissolved oxygen content of deoxygenator outlet feedwater by the oxygen table.
In step 806, determine the oxygen supplying flow of needs according to the dissolved oxygen content of the dissolved oxygen content of condensate pump inlet condensed water and deoxygenator outlet feedwater.
In step 808,,, it is in the desired range of values by the oxygen flow of gas flow regulating valve adjusting from oxygen source in the condensate pump ingress.Other flow control valves can be various manually, magnetic valve or motor-driven control valve.Above-mentioned steps 802 to 808 can circulate and carry out.
The oxygen replenishing method of station boiler provided by the invention and device are used for feedwater weak oxide processing (or AVT (the O)) mode of power plant's high pressure high temperature turbosets, in order to replenish, adjust, the dissolved oxygen of control condensed water and economizer feedwater meets working condition requirement.The present invention has simplified system by selecting oxygenating point and flow adjustment design, has improved the security of system reliability; Stablize oxygenation pressure reduction, added oxygen flow and be not subjected to the unit load variable effect, simplified control; System component uses the normal pressure standard component, and flow control is accurate; Dissolved oxygen level safety does not have influence to system material.
WOT mode of the present invention is compared with the OT mode, has following characteristics: 1) oxygenating amount is little, and normal pressure only is 10
2The ml/min magnitude needs bigger volumetric flow rate to guarantee to adjust control accuracy; 2) oxygenating concentration is low, with the same magnitude of the normal dissolved oxygen content of condensed water, can consider its influence to materials such as precision processing resins, needn't consider its influence to the condensate pump operation, and the oxygenating point needn't design the medium voltage network after precision processing; 3) it is relatively stable that weak oxide processing oxygenating requires flow.The problem that the OT mode of prior art exists mainly comes from the oxygenation point selection.The pressure rating that adds oxygen point is brought a series of problems with load variations.The present invention is according to the oxygenating characteristics of WOT, change the oxygenating point, the oxygenating point is selected on the condensate pipe that flows before the condensate pump, overcome the subject matter of the OT oxygenation existence of prior art, has following advantage: 1), be stable negative pressure by the oxygenating point being reelected on the condensate pipe that before condensate pump, flows; 2) select normal pressure oxygen pressure-regulator for use, flow control valve is in the pressure-regulator downstream, make its operating pressure and correcting state approaching, it is comparatively accurate to show: 3) pressure reduction keeps relative stability between oxygen supplementing device and condensed water, can not make oxygen-adding amount and condensing water flow inverse change because of load variations; 4) under the normal pressure, the oxygenating volumetric flow rate reaches 10
2Ml/min magnitude, under meter have enough accuracy and guarantee accurately regulation and control; 5) be the normal pressure system, safe.
Description of the invention provides for example with for the purpose of describing, and is not exhaustively or limit the invention to disclosed form.Many modifications and variations are obvious for the ordinary skill in the art.Selecting and describing embodiment is for better explanation principle of the present invention and practical application, thereby and makes those of ordinary skill in the art can understand the various embodiment that have various modifications that the present invention's design is suitable for specific end use.