發(fā)布時(shí)間：2018-05-19 11:08

  本文選題：高含鹽廢水 + 近零排放�。� 參考：《重慶交通大學(xué)》2016年碩士論文

【摘要】：高含鹽廢水是工業(yè)廢水中極難處理的廢水之一,具有含鹽量高、含鹽成分復(fù)雜、易產(chǎn)生結(jié)垢和腐蝕現(xiàn)象、有機(jī)物濃度高且難以降解等特點(diǎn),如何將其處理并達(dá)到“近零排放”的低能耗、高處理效率要求,成為國(guó)內(nèi)環(huán)保領(lǐng)域的一大難題,因此,探尋一種經(jīng)濟(jì)高效的高含鹽廢水近零排放處理技術(shù)是非常必要的。機(jī)械蒸汽再壓縮(Mechanical Vapor Recompression,MVR)技術(shù)是一種高效除鹽的近零排放技術(shù),本論文針對(duì)高含鹽廢水的特性,提出一種新型的內(nèi)置式MVR蒸發(fā)處理工藝,在數(shù)值模擬計(jì)算的基礎(chǔ)上,研究MVR內(nèi)部工作過(guò)程,得到強(qiáng)化傳熱方案,為高含鹽廢水減量化和零排放奠定一定的基礎(chǔ)。論文以脫硫廢水為研究對(duì)象,采用塑料膜作為板式換熱器的換熱元件,開(kāi)發(fā)出一種新型的降膜式換熱器——板式薄膜換熱器,在真空度為80kPa,蒸發(fā)溫度為60℃,溫差為2.3℃,壓差為2kPa的條件下,提出適合于處理脫硫廢水的MVR處理工藝,分析板式薄膜換熱器結(jié)構(gòu)特性和MVR工藝的節(jié)能原理,計(jì)算工藝系統(tǒng)的物料平衡和熱平衡。論文采用Gambit軟件建立板式薄膜換熱器的二維幾何模型,利用Fluent軟件實(shí)現(xiàn)換熱器內(nèi)部全流道數(shù)值模擬。在塑料熱交換膜壁厚0.07mm、脫硫廢水入口溫度40℃、進(jìn)料量0.6 m~3/h的工藝條件下,得到板式薄膜換熱器內(nèi)部的流場(chǎng)、速度場(chǎng)、溫度場(chǎng)和壓力場(chǎng)的分布情況,從換熱器內(nèi)部介質(zhì)的流動(dòng)與傳熱過(guò)程、熱交換膜內(nèi)部的傳熱過(guò)程等方面討論MVR內(nèi)部工作過(guò)程,為強(qiáng)化MVR傳熱提供一定的理論依據(jù)。論文采用響應(yīng)面和Fluent數(shù)值模擬相結(jié)合的方法,對(duì)MVR工藝進(jìn)行強(qiáng)化傳熱優(yōu)化設(shè)計(jì)。對(duì)塑料熱交換膜壁厚分別為0.04mm、0.07mm、0.10mm,脫硫廢水入口溫度分別為20℃、40℃、60℃,進(jìn)料量分別為0.4 m~3/h、0.6 m~3/h、0.8 m~3/h的多組工藝條件,利用響應(yīng)面法中的Box-Behnken試驗(yàn)設(shè)計(jì)方法進(jìn)行優(yōu)化方案設(shè)計(jì),并利用Fluent軟件模擬得到響應(yīng)值。優(yōu)化結(jié)果:熱交換膜壁厚0.04mm、脫硫廢水入口溫度60℃、進(jìn)料量0.59m~3/h時(shí)MVR傳熱性能最佳。MVR近零排放技術(shù)可使高含鹽廢水的除鹽率達(dá)99%以上,回收率達(dá)95%,廢水排放量?jī)H為5%,實(shí)現(xiàn)了高含鹽廢水的減量化。
[Abstract]:High salt wastewater is one of the most difficult wastewater treatment in industrial wastewater. It has the characteristics of high salt content, complex salt composition, easy to scale and corrosion, high concentration of organic matter and difficult to degrade. How to treat it and achieve the requirement of low energy consumption and high treatment efficiency of "near zero discharge" has become a major problem in the field of environmental protection in China. Therefore, it is very necessary to explore an economical and efficient treatment technology for near-zero discharge of high-salt wastewater. Mechanical Vapor recompression (Vapor) is a near zero discharge technology for high efficiency desalination. In this paper, a new type of built-in MVR evaporation treatment process is proposed, which is based on numerical simulation. The internal working process of MVR was studied, and the enhanced heat transfer scheme was obtained, which laid a foundation for the reduction and zero discharge of high salt wastewater. In this paper, a new type of falling film heat exchanger-plate membrane heat exchanger is developed by using plastic film as heat exchanger element and desulfurization wastewater as research object. The vacuum degree is 80 KPA, the evaporation temperature is 60 鈩，

本文編號(hào)：1909869