吳基富
(云浮發(fā)電廠(B)廠有限公司,廣東 云浮 527300)
摘要:通過介紹汽輪機(jī)組閉冷水系統(tǒng)的概況,論述閉冷水系統(tǒng)優(yōu)化改造的必要性,并結(jié)合相關(guān)節(jié)能改造措施,選擇正確的改造方案,對(duì)汽輪機(jī)組閉冷水系統(tǒng)進(jìn)行節(jié)能改造。運(yùn)行結(jié)果表明,該改造方案有效降低了閉冷水系統(tǒng)能源損耗,具有良好的系統(tǒng)工作效益,值得推廣應(yīng)用。
關(guān)鍵詞:汽輪機(jī);閉冷水系統(tǒng);節(jié)能;改造
中圖分類號(hào):TK264.1文獻(xiàn)標(biāo)識(shí)碼:A 文章編號(hào):2095-6835(2014)08-0022-02
1閉冷水系統(tǒng)概況
機(jī)組閉冷水系統(tǒng)的功能是向汽輪機(jī)、鍋爐、發(fā)電機(jī)和脫硫系統(tǒng)等輔助設(shè)備提供冷卻水。該系統(tǒng)為閉式回路,開式冷卻水系統(tǒng)的水流經(jīng)閉冷器,來冷卻閉式循環(huán)水系統(tǒng)中的冷卻水。閉冷水系統(tǒng)包括2臺(tái)全容量閉冷泵、3臺(tái)半容量閉冷器和1臺(tái)膨脹水箱設(shè)備。閉冷水系統(tǒng)采用除鹽水和凝結(jié)水作為冷卻液,用凝結(jié)水輸送泵或除鹽水泵向膨脹水箱補(bǔ)水,然后通過閉冷泵在閉式回路中循環(huán)。閉冷水系統(tǒng)用戶主要有主機(jī)潤(rùn)滑油冷卻器、小機(jī)潤(rùn)滑油冷卻器、EH油冷卻器、真空泵冷卻器、密封油冷卻器、發(fā)電機(jī)器定子水冷卻器和鍋爐各風(fēng)機(jī)潤(rùn)滑油冷卻器等。閉冷水系統(tǒng)正常運(yùn)行時(shí),1臺(tái)閉冷泵運(yùn)行,閉冷水系統(tǒng)出力應(yīng)滿足機(jī)組最大出力時(shí)各種負(fù)荷運(yùn)行的需要,并有一定裕量。
2閉冷水系統(tǒng)優(yōu)化改造的必要性
2.1全年閉冷水系統(tǒng)運(yùn)行狀況
查閱安全儀表系統(tǒng)(SIS),采集閉冷水系統(tǒng)運(yùn)行數(shù)據(jù),繪制出某發(fā)電廠閉冷水系統(tǒng)2012年全年運(yùn)行狀況,如圖1所示。
圖1機(jī)組閉冷水系統(tǒng)冷卻水運(yùn)行溫度
圖2閉冷泵流量和效率特性曲線
2.2閉冷水系統(tǒng)運(yùn)行狀況分析
該發(fā)電廠地處北亞熱帶濕潤(rùn)季風(fēng)氣候區(qū),具有四季分明、雨量充沛、日照充足、冬寒夏熱和雨熱同步等特點(diǎn)。由于環(huán)境溫度的變化,導(dǎo)致閉冷水溫度隨著季節(jié)變化而變化。由圖1可知,閉冷水冷卻器出口溫度僅在6—9月會(huì)超過35 ℃,全年平均溫度在25 ℃左右。變冷泵流量和效率特性曲線由圖2所示,閉冷水系統(tǒng)用戶冷卻器進(jìn)口調(diào)整門開度在7—9月超過80%,平均開度在50%左右;特別是在冬季,其開度在20%左右,閉冷水系統(tǒng)用戶各冷卻器所需要的冷卻水量較設(shè)計(jì)值偏離大。由圖2可知,閉冷水系統(tǒng)冷卻器全年出口壓力平均值為0.65 MPa左右。 2.3閉冷水系統(tǒng)全年用戶冷卻水量分析
閉冷泵型號(hào)為SLOW300—550IB,額定流量為2 000 m3/h,揚(yáng)程為50 m,功率為400 kW,其特性曲線如圖2所示。由圖2可知,6—9月閉冷水流量為1 500~2 000 m3/h,其他月份為750~1 250 m3/h。
通過以上分析可知,6—9月,閉冷泵可匹配系統(tǒng)經(jīng)濟(jì)運(yùn)行,泵的效率較高、節(jié)流損失??;其他月份,由于閉冷水溫度隨著環(huán)境溫度大幅下降,閉冷水流量也急劇下降,閉冷泵雖然能夠滿足閉冷水系統(tǒng)運(yùn)行的需要,但泵的節(jié)流損失大、效率低,閉冷泵不再經(jīng)濟(jì)地匹配閉冷水系統(tǒng)運(yùn)行,造成能源浪費(fèi)。
由此可見,該電廠機(jī)組閉冷水系統(tǒng)配置的閉冷泵裕量過大,系統(tǒng)母管長(zhǎng)期處于較高壓力下運(yùn)行,對(duì)泵、閥門密封件、調(diào)整門閥芯是不利的,縮短了其使用壽命,閉冷水系統(tǒng)運(yùn)行經(jīng)濟(jì)性較差。所以,對(duì)閉冷系統(tǒng)的節(jié)能進(jìn)行改造是十分必要的。
3閉冷水系統(tǒng)節(jié)能改造方案選擇
3.1閉冷泵改為變頻運(yùn)行
閉冷泵改為變頻運(yùn)行時(shí),閉冷泵根據(jù)系統(tǒng)用戶用水量的多少改變轉(zhuǎn)速,保持系統(tǒng)母管壓力在合理、經(jīng)濟(jì)的范圍內(nèi),運(yùn)行靈活,節(jié)約廠用電量。但是,變頻改造投資大,涉及電氣、控制和土建等專業(yè),必須由設(shè)計(jì)院等相關(guān)單位完成。
3.2在閉冷水系統(tǒng)中增加1臺(tái)小泵
閉冷水系統(tǒng)用水量長(zhǎng)期為750~1 250 m3/h,選擇額定流量為1 000~1 200 m3/h、揚(yáng)程為40 m的水泵,與#1,#2閉冷泵并聯(lián)運(yùn)行,就可以滿足閉冷水系統(tǒng)各冷卻器的需求。該電廠220 MW機(jī)組正進(jìn)行拆除,機(jī)組的射水泵額定流量為1 201 m3/h,揚(yáng)程為40 m,完全可以滿足機(jī)組閉冷水系統(tǒng)除6—9月以外8個(gè)月份的運(yùn)行。
該方案投資小,后期運(yùn)行維護(hù)量較變頻方案少,系統(tǒng)運(yùn)行可靠,廠用電節(jié)約明顯,本廠檢修部門即可獨(dú)立完成閉冷水系統(tǒng)的節(jié)能改造。因此,電廠機(jī)組閉冷水系統(tǒng)節(jié)能改造選擇第二種方案。
4閉冷水系統(tǒng)節(jié)能改造措施
大修期間,在閉冷水進(jìn)出水母管上引出1路管道,加裝1臺(tái)閉冷泵,并安裝進(jìn)出電動(dòng)門、出口逆止門、進(jìn)口濾網(wǎng)和進(jìn)出口壓力表。為了不影響美觀,將水泵安裝在閉冷泵與前置泵之間。
4.1改造成本
閉冷水系統(tǒng)節(jié)能的改造成本主要有:管道0.5萬(wàn)元;進(jìn)出口閥門,利用#4機(jī)組2臺(tái)射水泵出口門,只增購(gòu)1個(gè)出口逆止門,0.5萬(wàn)元;電纜7.0萬(wàn)元;熱控電動(dòng)閥門5.0萬(wàn)元;基礎(chǔ)設(shè)施0.5萬(wàn)元,總成本13.5萬(wàn)元。相對(duì)于購(gòu)置1臺(tái)新泵和電機(jī)及其附屬管閥等,節(jié)約費(fèi)用約15萬(wàn)元。
4.2預(yù)期收益
按該水泵運(yùn)行240 d,按75%的負(fù)荷率計(jì)算,全年可節(jié)約(400-185)×24×240×0.48×0.75×10-4=44.582 4(萬(wàn)元),2臺(tái)機(jī)組全部實(shí)施改造后,將每年產(chǎn)生89.170 8萬(wàn)元的經(jīng)濟(jì)收益。改造后,#1,#2閉冷泵型號(hào)為SLOW300-550IB,#3閉冷泵型號(hào)為350S-44AG。6—9月使用#1,#2閉冷泵運(yùn)行,其余月份使用#3泵運(yùn)行,極大地提高了閉冷水系統(tǒng)運(yùn)行的經(jīng)濟(jì)性和可靠性,達(dá)到了節(jié)能降耗的目的。改造后閉冷水系統(tǒng)簡(jiǎn)圖如圖3所示。
圖3改造后閉冷水系統(tǒng)簡(jiǎn)圖
5改造后閉冷水系統(tǒng)運(yùn)行狀況
改造后,系統(tǒng)運(yùn)行穩(wěn)定,機(jī)組滿負(fù)荷運(yùn)行時(shí)閉冷水系統(tǒng)使用#3泵的運(yùn)行狀況見表1所示。
由表1可知,1—5月和10月,#3閉冷泵揚(yáng)程和流量完全滿足閉冷水系統(tǒng)用戶的需求,改造取得了預(yù)期的效果。
6結(jié)束語(yǔ)
綜上所述,通過對(duì)電廠機(jī)組閉冷水系統(tǒng)改造方案的實(shí)施,證明了閉冷水系統(tǒng)的節(jié)能改造是具有極大經(jīng)濟(jì)意義的。該節(jié)能
改造方案節(jié)能效果明顯,既提高了設(shè)備效率,又滿足了生產(chǎn)工藝的要求,具有一定的推廣價(jià)值,應(yīng)該在汽輪機(jī)改造工程中廣泛發(fā)展應(yīng)用。
表1閉冷水系統(tǒng)主要運(yùn)行參數(shù)
月份 室外溫度/℃ 閉式水冷卻器出口溫度/℃ 閉式水冷卻器出口壓力/MPa
1 2 16 0.63
2 5 20 0.60
3 10 24 0.55
4 18 25 0.45
5 20 28 0.42
10 22 29 0.38
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〔編輯:李玨〕
Explore Energy Saving Turbine Closed Water System
Wu Jifu
Abstract: Introduction Turbine closed water system overview, discusses the need for the transformation of closed water system optimization, combined with relevant energy saving measures to select the correct transformation program, closed cooling water system for steam turbine for energy saving. The result shows that the transformation program closed water system effectively reduces energy consumption, has a good system of work benefits, and should be widely applied.
Key words: turbine; closed cooling water system; energy conservation; transformation
(上接第19頁(yè))
參考文獻(xiàn)
[1]劉菊青,方斌.淺談機(jī)電一體化技術(shù)在煤礦生產(chǎn)的應(yīng)用及推廣[J].山東工業(yè)技術(shù),2013(9).
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[3]顏平.機(jī)電一體化產(chǎn)品在平頂山天安煤業(yè)生產(chǎn)中的應(yīng)用與探討[J].機(jī)電信息,2010(4).
[4]閆立偉.機(jī)電技術(shù)一體化技術(shù)在當(dāng)前我國(guó)煤礦開采中的應(yīng)用[J].電源技術(shù)應(yīng)用,2013(12).
〔編輯:白潔〕
On the Practical Application of Mechatronics and Future Mine Development
Ding Liao
Abstract: Mechatronics technology in coal production and more widely, it can not only improve the safety of coal mine production operations, but also reduce the miners labor intensity and improve work efficiency, coal mining enterprises tremendous economic benefits. Based on this, the practical application of mechatronics mine and future development are briefly discussed.
Key words: coal; mechatronics; application; development
(上接第20頁(yè))
Flame Atomic Absorption Spectrophotometric Measurement of Lead in Wastewater
Lin Songhe
Abstract: Flame atomic absorption spectrophotometry can effectively detect metal ion content in wastewater, wastewater treatment methods to determine.
Key words: flame atomic absorption spectrophotometry; wastewater; lead; spectral lines
(上接第21頁(yè))
The Improvement of Xiaohuigou Coal Mine Local Ventilator Dedicated Power Supply Scheme
Han Dezhu
Abstract: Mainly for Xiaohuigou Coal Mine local ventilator dedicated power supply plan before and after the improvement of safety and reliability, briefly discusses the advantages and disadvantages of the improved scheme and the improved economic benefits and social benefits.
Key words: coal mine; local ventilator; power supply; improved scheme
Key words: turbine; closed cooling water system; energy conservation; transformation
(上接第19頁(yè))
參考文獻(xiàn)
[1]劉菊青,方斌.淺談機(jī)電一體化技術(shù)在煤礦生產(chǎn)的應(yīng)用及推廣[J].山東工業(yè)技術(shù),2013(9).
[2]李萍.煤礦機(jī)電一體化的技術(shù)應(yīng)用和節(jié)能改造探討[J].科學(xué)之友,2013(10).
[3]顏平.機(jī)電一體化產(chǎn)品在平頂山天安煤業(yè)生產(chǎn)中的應(yīng)用與探討[J].機(jī)電信息,2010(4).
[4]閆立偉.機(jī)電技術(shù)一體化技術(shù)在當(dāng)前我國(guó)煤礦開采中的應(yīng)用[J].電源技術(shù)應(yīng)用,2013(12).
〔編輯:白潔〕
On the Practical Application of Mechatronics and Future Mine Development
Ding Liao
Abstract: Mechatronics technology in coal production and more widely, it can not only improve the safety of coal mine production operations, but also reduce the miners labor intensity and improve work efficiency, coal mining enterprises tremendous economic benefits. Based on this, the practical application of mechatronics mine and future development are briefly discussed.
Key words: coal; mechatronics; application; development
(上接第20頁(yè))
Flame Atomic Absorption Spectrophotometric Measurement of Lead in Wastewater
Lin Songhe
Abstract: Flame atomic absorption spectrophotometry can effectively detect metal ion content in wastewater, wastewater treatment methods to determine.
Key words: flame atomic absorption spectrophotometry; wastewater; lead; spectral lines
(上接第21頁(yè))
The Improvement of Xiaohuigou Coal Mine Local Ventilator Dedicated Power Supply Scheme
Han Dezhu
Abstract: Mainly for Xiaohuigou Coal Mine local ventilator dedicated power supply plan before and after the improvement of safety and reliability, briefly discusses the advantages and disadvantages of the improved scheme and the improved economic benefits and social benefits.
Key words: coal mine; local ventilator; power supply; improved scheme
Key words: turbine; closed cooling water system; energy conservation; transformation
(上接第19頁(yè))
參考文獻(xiàn)
[1]劉菊青,方斌.淺談機(jī)電一體化技術(shù)在煤礦生產(chǎn)的應(yīng)用及推廣[J].山東工業(yè)技術(shù),2013(9).
[2]李萍.煤礦機(jī)電一體化的技術(shù)應(yīng)用和節(jié)能改造探討[J].科學(xué)之友,2013(10).
[3]顏平.機(jī)電一體化產(chǎn)品在平頂山天安煤業(yè)生產(chǎn)中的應(yīng)用與探討[J].機(jī)電信息,2010(4).
[4]閆立偉.機(jī)電技術(shù)一體化技術(shù)在當(dāng)前我國(guó)煤礦開采中的應(yīng)用[J].電源技術(shù)應(yīng)用,2013(12).
〔編輯:白潔〕
On the Practical Application of Mechatronics and Future Mine Development
Ding Liao
Abstract: Mechatronics technology in coal production and more widely, it can not only improve the safety of coal mine production operations, but also reduce the miners labor intensity and improve work efficiency, coal mining enterprises tremendous economic benefits. Based on this, the practical application of mechatronics mine and future development are briefly discussed.
Key words: coal; mechatronics; application; development
(上接第20頁(yè))
Flame Atomic Absorption Spectrophotometric Measurement of Lead in Wastewater
Lin Songhe
Abstract: Flame atomic absorption spectrophotometry can effectively detect metal ion content in wastewater, wastewater treatment methods to determine.
Key words: flame atomic absorption spectrophotometry; wastewater; lead; spectral lines
(上接第21頁(yè))
The Improvement of Xiaohuigou Coal Mine Local Ventilator Dedicated Power Supply Scheme
Han Dezhu
Abstract: Mainly for Xiaohuigou Coal Mine local ventilator dedicated power supply plan before and after the improvement of safety and reliability, briefly discusses the advantages and disadvantages of the improved scheme and the improved economic benefits and social benefits.
Key words: coal mine; local ventilator; power supply; improved scheme