本文選題：熱力系統(tǒng) + 熱經(jīng)濟(jì)性��； 參考：《重慶大學(xué)》2014年碩士論文

【摘要】：隨著我國(guó)經(jīng)濟(jì)發(fā)展，與能源與環(huán)境之間的矛盾日益突出，，火電機(jī)組的節(jié)能減排成為一個(gè)備受關(guān)注的問題。為了更好地實(shí)現(xiàn)節(jié)能減排，國(guó)內(nèi)已建電廠及新設(shè)計(jì)火電廠工程中，有很多項(xiàng)目采用低壓省煤器系統(tǒng)進(jìn)行煙氣余熱回收。由于計(jì)算方法的差異性，導(dǎo)致對(duì)煙氣余熱回收利用的經(jīng)濟(jì)性評(píng)價(jià)一直存在爭(zhēng)議。在這種背景下，急需找到鍋爐排煙余熱利用經(jīng)濟(jì)性的合理評(píng)價(jià)方法，提高排煙余熱的能量轉(zhuǎn)換效率，進(jìn)一步降低發(fā)電能耗。 煙氣余熱回收利用，屬于外部熱量利用于系統(tǒng)，可以通過循環(huán)函數(shù)法給以定量分析。本文基于循環(huán)函數(shù)法，從反平衡的角度，建立了局部定量計(jì)算完整的數(shù)學(xué)模型。把這些模型應(yīng)用在補(bǔ)水方式、凝結(jié)水過冷度等局部定量分析中，分別結(jié)合某300MW亞臨界機(jī)組和某1000MW超超臨界機(jī)組進(jìn)行實(shí)例計(jì)算分析。結(jié)合某300MW亞臨界機(jī)組，將循環(huán)函數(shù)法的定量計(jì)算模型應(yīng)用在低壓省煤器的熱經(jīng)濟(jì)性分析中，研究了低壓省煤器的運(yùn)行特性以及最佳安裝位置。 主要研究成果如下： ①最后單元進(jìn)水系數(shù)即為系統(tǒng)不可逆性的反映，減小最后單元進(jìn)水系數(shù)和提高循環(huán)吸熱量，都可以提高機(jī)組的效率。循環(huán)函數(shù)法的定量計(jì)算模型具有概念清晰、通用性強(qiáng)、便于計(jì)算機(jī)程序化等特點(diǎn)。 ②建立了低壓省煤器優(yōu)化運(yùn)行數(shù)學(xué)模型，得到了最優(yōu)水流量，在額定工況下，水流量為69.2kg/s時(shí)，機(jī)組效率相對(duì)增量最大，為0.722%。通過對(duì)比試驗(yàn)數(shù)據(jù)和理論計(jì)算結(jié)果，驗(yàn)證了循環(huán)函數(shù)法定量計(jì)算模型的準(zhǔn)確性與可靠性。 ③研究了低壓省煤器的主要運(yùn)行特性，這些特性具有普遍性，可以指導(dǎo)生產(chǎn)實(shí)踐。研究了低壓省煤器的最佳安裝位置，結(jié)果表明，方案的考察和選擇應(yīng)從材料價(jià)格、能源供應(yīng)等角度來綜合分析。
[Abstract]:With the development of economy in China, the contradiction between energy and environment is becoming more and more serious. In order to achieve better energy saving and emission reduction, there are many projects in domestic power plants and newly designed thermal power plants that use low-pressure economizer system to recover flue gas waste heat. Due to the difference of calculation methods, the economic evaluation of flue gas waste heat recovery and utilization has been controversial. Under this background, it is urgent to find a reasonable evaluation method for the utilization economy of waste heat of boiler exhaust gas, to improve the energy conversion efficiency of waste heat of exhaust gas and to further reduce the energy consumption of power generation. The recovery and utilization of flue gas waste heat belongs to the system of external heat utilization, which can be quantitatively analyzed by circulation function method. Based on the cyclic function method and from the point of view of counterbalance, a complete mathematical model for local quantitative calculation is established in this paper. These models are applied to the local quantitative analysis of water supply mode, condensate undercooling and so on. Combined with a 300MW subcritical unit and a 1000MW ultra-supercritical unit, the calculation and analysis are carried out respectively. Combined with a 300MW subcritical unit, the quantitative calculation model of cyclic function method is applied to the thermal economic analysis of low pressure economizer. The operation characteristics and optimal installation position of low pressure economizer are studied. The main research results are as follows: 1Inlet coefficient of the final unit is the reflection of the irreversibility of the system. The efficiency of the unit can be improved by reducing the influent coefficient of the final unit and increasing the heat absorption of the cycle. The quantitative calculation model of cyclic function method has the characteristics of clear concept, strong generality and easy to be programmed by computer. (2) the mathematical model of optimal operation of low pressure economizer is established, and the optimal water flow rate is obtained under rated working conditions. When the water flow is 69.2kg/s, the relative increment of unit efficiency is the largest, 0.722. By comparing the experimental data with the theoretical results, the accuracy and reliability of the calculation model of cyclic function method are verified. 3 the main operating characteristics of low pressure economizer are studied, and these characteristics are universal. Can guide production practice. The optimum installation position of low pressure economizer is studied. The results show that the inspection and selection of the scheme should be comprehensively analyzed from the point of view of material price and energy supply.
【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TM621

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 姜延燦;韋成國(guó);;200MW機(jī)組加裝低壓省煤器后性能試驗(yàn)分析[J];重慶電力高等專科學(xué)校學(xué)報(bào);2008年04期

2 劉志真;300MW機(jī)組蒸汽冷卻器熱經(jīng)濟(jì)性分析[J];長(zhǎng)沙電力學(xué)院學(xué)報(bào)(自然科學(xué)版);2003年03期

3 趙之軍;馮偉忠;張玲;于娟;胡興勝;殷國(guó)強(qiáng);;電站鍋爐排煙余熱回收的理論分析與工程實(shí)踐[J];動(dòng)力工程;2009年11期

4 黃新元;龍口電廠1號(hào)爐低壓省煤器優(yōu)化設(shè)計(jì)[J];鍋爐技術(shù);1998年03期

5 劉鶴忠;連正權(quán);;低溫省煤器在火力發(fā)電廠中的運(yùn)用探討[J];電力勘測(cè)設(shè)計(jì);2010年04期

6 王培紅,汪孟樂;等效抽汽法在再熱機(jī)組中的應(yīng)用[J];汽輪機(jī)技術(shù);1996年06期

7 黃新元;孫奉仲;史月濤;;低壓省煤器系統(tǒng)節(jié)能理論及其在火電廠的應(yīng)用[J];山東電力技術(shù);2008年02期

8 黃新元,平亞明,孫奉仲;火力發(fā)電廠低壓省煤器系統(tǒng)的最佳水量分配[J];水動(dòng)力學(xué)研究與進(jìn)展(A輯);2003年05期

9 富春光;;鍋爐煙氣余熱回收技術(shù)的應(yīng)用探討[J];熱電技術(shù);2012年02期

10 方曉玲;;火力發(fā)電廠節(jié)能設(shè)計(jì)技術(shù)應(yīng)用綜述[J];能源與節(jié)能;2012年12期

相關(guān)博士學(xué)位論文 前1條

1 陸萬鵬;基于電站鍋爐排煙余熱的機(jī)爐煙氣回?zé)嵫h(huán)理論與應(yīng)用研究[D];山東大學(xué);2012年

本文編號(hào)：2102796