摘要:高效的城市污水取水技術(shù)是原生污水源熱泵系統(tǒng)可靠運行的前提。針對現(xiàn)有相關(guān)技術(shù)的不足,提出了開式集成污水取水技術(shù)。通過定義網(wǎng)眼阻塞系數(shù)、污物密度、截面系數(shù)等重要參數(shù),建立了表征其取水特性的數(shù)學(xué)模型,并提出了臨界運行工況的參數(shù)條件,考察了各臨界運行參數(shù)及不同旋轉(zhuǎn)周期下網(wǎng)眼阻塞系數(shù)等的變化規(guī)律。
關(guān)鍵詞: 污水源熱泵系統(tǒng);開式取水;數(shù)學(xué)模型;運行特性
中圖分類號:TU831.6
文獻標(biāo)志碼:A
文章編號:16744764(2014)02006206
Abstract:The effective sewage intake technology is prerequisite for the untreated sewage source heat pump system to run steadily. In terms of the insufficiency of current sewage intake technologies, an open sewage intake integration technology is proposed. The mathematical model and the distinguish basis of critical state are established for the sewage intake characteristic by defining some important operating parameters, such as the blocking coefficient, the contamination density and the section coefficient. Furthermore, the change rule of each critical operation parameter is observed along with the various initial parameters. The result can provide the theoretical basis to design the open intake integration technology.
Key words:sewage source heat pump system; open intake; mathematical model; operational characteristics
能源供需矛盾日益突出,建筑能耗巨大,占社會總能耗的30%以上,其中暖通空調(diào)的能耗就占據(jù)建筑用能的65%以上,因此大力開發(fā)利用可再生能源成為建筑用能可持續(xù)發(fā)展的有效出路之一[13]。城市原生污水這一新型可再生能源,因其分布廣泛、水量巨大[45],當(dāng)用作熱泵系統(tǒng)的低位熱源時,節(jié)能與環(huán)保優(yōu)勢顯著,從而備受各國青睞,成為近年爭相研究與應(yīng)用的熱點[610]。但由于其成分復(fù)雜性,若原生污水熱利用過程直接進換熱器,則污水中所含大尺度污雜物將在短時間內(nèi)將其堵塞,導(dǎo)致系統(tǒng)不能安全運行[1112]。因此,能夠防堵塞的高效污水取水技術(shù)成為熱泵系統(tǒng)研究與應(yīng)用的關(guān)鍵之一。
日本及北歐國家的污水源熱泵系統(tǒng)常采取機械刮剝、人工刷洗等方法來解決污水取水過程中換熱設(shè)備的防堵塞問題[57],存在工作量大、運行工況不穩(wěn)定的弊端。中國近年開發(fā)了反沖洗污水取水裝置,實現(xiàn)了穩(wěn)定、連續(xù)取水,并在多個工程中得到了成功的應(yīng)用,然而該裝置仍存在著取水設(shè)備承壓高、取排水內(nèi)泄露嚴重、濾面過濾負荷大等不足[1314]。因此,研究性能更加優(yōu)越的污水取水技術(shù)成為亟待解決的難點,故本文基于一種新提出的開式集成污水取水技術(shù)建立了開式原生污水源熱泵系統(tǒng),并將對系統(tǒng)取水的數(shù)學(xué)模型及運行特性作深入分析。
1開式原生污水源熱泵系統(tǒng)
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(編輯王秀玲)