全球(qiu)(qiu)核能(neng)系統已發(fa)(fa)展至(zhi)四(si)代(dai)(dai),我國核電裝備(bei)發(fa)(fa)展歷經(jing)30余年,從獨立探索、技(ji)術(shu)引 進到(dao)實現自主研制。相(xiang)比傳統石化(hua)能(neng)源(yuan)和其(qi)他可再生能(neng)源(yuan),核電具備(bei)清(qing)潔、低排(pai)放、 輸出穩定(ding)等(deng)優(you)勢。自20世(shi)紀50年代(dai)(dai)至(zhi)今,目(mu)前全球(qiu)(qiu)已發(fa)(fa)展四(si)代(dai)(dai)核能(neng)系統,逐步向(xiang)更(geng) 加安全、可持續方向(xiang)發(fa)(fa)展。我國核電經(jing)歷了從獨立探索向(xiang)引進國外先進技(ji)術(shu)及自主 化(hua)轉變,目(mu)前已掌握自主三(san)代(dai)(dai)核電技(ji)術(shu)。
目前(qian)我(wo)(wo)國(guo)(guo)在(zai)(zai)運(yun)行(xing)(xing)核(he)電(dian)(dian)(dian)(dian)容量遠低于(yu)美(mei)國(guo)(guo)、法國(guo)(guo),在(zai)(zai)建核(he)電(dian)(dian)(dian)(dian)裝機規模(mo)位居世界首位。根(gen) 據(ju)World Nuclear Association、中(zhong)國(guo)(guo)核(he)能行(xing)(xing)業(ye)協會(hui)、中(zhong)電(dian)(dian)(dian)(dian)聯數據(ju),截至2022年(nian)9月底, 全(quan)球(qiu)(qiu)已運(yun)行(xing)(xing)的核(he)電(dian)(dian)(dian)(dian)站中(zhong)我(wo)(wo)國(guo)(guo)核(he)電(dian)(dian)(dian)(dian)站發(fa)電(dian)(dian)(dian)(dian)容量位居全(quan)球(qiu)(qiu)第三位,但與(yu)前(qian)兩名國(guo)(guo)家相比(bi), 核(he)電(dian)(dian)(dian)(dian)發(fa)電(dian)(dian)(dian)(dian)容量差距較大,其中(zhong)法國(guo)(guo)核(he)電(dian)(dian)(dian)(dian)站發(fa)電(dian)(dian)(dian)(dian)量是我(wo)(wo)國(guo)(guo)的1.1倍(bei)(bei),美(mei)國(guo)(guo)核(he)電(dian)(dian)(dian)(dian)站發(fa)電(dian)(dian)(dian)(dian)量 是我(wo)(wo)國(guo)(guo)的近(jin)1.7倍(bei)(bei)。在(zai)(zai)建核(he)電(dian)(dian)(dian)(dian)規模(mo)方面,我(wo)(wo)國(guo)(guo)在(zai)(zai)建裝機量位居全(quan)球(qiu)(qiu)首位,且遠高于(yu)其 他國(guo)(guo)家,2010-2021年(nian)年(nian)均新增核(he)電(dian)(dian)(dian)(dian)裝機規模(mo)約4000MW。
從核(he)電(dian)(dian)裝(zhuang)(zhuang)機(ji)(ji)規劃(hua)來(lai)看(kan),目前(qian)我(wo)(wo)(wo)國(guo)(guo)核(he)電(dian)(dian)裝(zhuang)(zhuang)機(ji)(ji)缺口(kou)較(jiao)大,未來(lai)5-10年有(you)望持續建(jian)設(she)。根 據中(zhong)電(dian)(dian)聯《電(dian)(dian)力(li)行業“十四五(wu)”發展規劃(hua)研(yan)究(jiu)》,2025年我(wo)(wo)(wo)國(guo)(guo)將(jiang)實現核(he)電(dian)(dian)裝(zhuang)(zhuang)機(ji)(ji) 70000MW的目標。根據中(zhong)國(guo)(guo)核(he)能協(xie)會(hui)數據,在(zai)已(yi)投運方面,截(jie)至2022年9月,我(wo)(wo)(wo)國(guo)(guo) 運行核(he)電(dian)(dian)機(ji)(ji)組(zu)共有(you)54臺,裝(zhuang)(zhuang)機(ji)(ji)容量約55806MW。因(yin)此,當前(qian)我(wo)(wo)(wo)國(guo)(guo)核(he)電(dian)(dian)機(ji)(ji)組(zu)裝(zhuang)(zhuang)機(ji)(ji)政策(ce) 需求缺口(kou)總(zong)計約14194MW。根據World Nuclear Association數據,截(jie)至2022年12月, 我(wo)(wo)(wo)國(guo)(guo)在(zai)建(jian)核(he)電(dian)(dian)規模總(zong)計約22867MW,參考在(zai)建(jian)核(he)電(dian)(dian)項目建(jian)設(she)規劃(hua),核(he)電(dian)(dian)開(kai)工至并網 通(tong)常需要5年左(zuo)右。總(zong)體來(lai)看(kan),預(yu)計未來(lai)5年我(wo)(wo)(wo)國(guo)(guo)核(he)電(dian)(dian)建(jian)設(she)規模空間較(jiao)大、持續性(xing)強。
蒸(zheng)(zheng)(zheng)汽發(fa)生(sheng)(sheng)(sheng)器是(shi)核(he)(he)能系統關鍵設備,對核(he)(he)電廠(chang)的(de)安(an)全運(yun)行十(shi)分(fen)重(zhong)要(yao)。根據姜素云(yun)《核(he)(he) 電蒸(zheng)(zheng)(zheng)發(fa)器用傳熱管(guan)生(sheng)(sheng)(sheng)產工藝簡(jian)介》,在核(he)(he)能系統中,蒸(zheng)(zheng)(zheng)汽發(fa)生(sheng)(sheng)(sheng)器的(de)主要(yao)作(zuo)用是(shi)通過管(guan) 束(shu)的(de)換熱作(zuo)用產生(sheng)(sheng)(sheng)高品質干燥蒸(zheng)(zheng)(zheng)汽,通過主蒸(zheng)(zheng)(zheng)汽管(guan)道來驅動汽輪發(fa)電機組(zu)發(fa)電。由 于(yu)核(he)(he)電一回路(lu)冷卻劑(ji)流經(jing)堆芯帶(dai)有放射(she)性(xing)(xing),因此蒸(zheng)(zheng)(zheng)汽發(fa)生(sheng)(sheng)(sheng)器也(ye)用于(yu)防止放射(she)性(xing)(xing)物質 外泄。壓水(shui)堆核(he)(he)電廠(chang)的(de)非計劃(hua)停堆次數中約有四分(fen)之一與蒸(zheng)(zheng)(zheng)汽發(fa)生(sheng)(sheng)(sheng)器問(wen)題有關,因 此蒸(zheng)(zheng)(zheng)汽發(fa)生(sheng)(sheng)(sheng)器對核(he)(he)電廠(chang)的(de)安(an)全運(yun)行十(shi)分(fen)重(zhong)要(yao)。
核電蒸發器用 U型傳熱管主要作用是隔離和傳熱,材料可靠性要求高。
1. 作(zuo)用(yong)(yong)(yong): 核電蒸發器用(yong)(yong)(yong)傳(chuan)熱(re)管均選用(yong)(yong)(yong) U 型管,核心作(zuo)用(yong)(yong)(yong)是隔離和傳(chuan)熱(re),即在(zai)內(nei)表面流(liu)通(tong)(tong)的(de)是 帶放射(she)性的(de)熱(re)量較高的(de)一回(hui)路工質水(shui)(shui),在(zai)外表面流(liu)通(tong)(tong)的(de)是取自自然界的(de)海水(shui)(shui)或河水(shui)(shui) 經必要處理的(de)用(yong)(yong)(yong)來產(chan)生蒸汽(qi)的(de)二回(hui)路工質水(shui)(shui),通(tong)(tong)過(guo)它將一回(hui)路水(shui)(shui)的(de)熱(re)能傳(chuan)導(dao)給二回(hui) 路水(shui)(shui)并使其變成蒸汽(qi)。
3. 要(yao)求:其(qi)可靠性(xing)直接(jie)(jie)影響到核電(dian)廠的安(an)全性(xing)與經濟性(xing), 因此傳熱(re)管(guan)應具(ju)備下列性(xing)能(neng): 熱(re)強性(xing)、熱(re)穩(wen)定(ding)性(xing)和(he)熱(re)焊接(jie)(jie)性(xing)能(neng)好(hao); 基體組織(zhi)穩(wen)定(ding)、熱(re) 導率高、熱(re)膨脹系數小; 抗均(jun)勻腐(fu)蝕(shi)和(he)抗局部腐(fu)蝕(shi)能(neng)力強; 具(ju)有足(zu)夠的塑性(xing)和(he)韌性(xing)。