本文選題：氣浮 + 溶氣法　； 參考：《西安石油大學(xué)》2017年碩士論文

【摘要】：氣浮凈水技術(shù)是一種能夠?qū)崿F(xiàn)固液分離或液液分離的凈水方法,它被廣泛的應(yīng)用于石油工業(yè)、毛紡工業(yè)、食品工業(yè)以及造紙廢水處理等領(lǐng)域。壓力溶氣法是氣浮凈水技術(shù)中生成微氣泡的方法之一,該方法生成的微氣泡具有尺寸細(xì)微、大小均勻、數(shù)量大等特點(diǎn)。壓力溶氣氣浮法凈水的原理是:在高壓下通過使空氣分子進(jìn)入水分子間隙或與水分子發(fā)生反應(yīng)生成水合物的方法將空氣溶解在水中,之后令壓力溶氣水經(jīng)過釋放器減壓、消能,氣體分子就會(huì)迅速聚集形成大量細(xì)微、均勻的微小氣泡,微小氣泡與水中的雜質(zhì)結(jié)合,最終攜帶雜質(zhì)上浮至水面從而達(dá)到凈化水體的過程。壓力溶氣氣浮法影響凈水效果的最主要因素是微氣泡的尺寸以及數(shù)量。研究壓力溶氣氣浮法氣體在水中的溶解過程、氣泡生成的過程以及影響氣泡尺寸的因素對(duì)提高氣浮凈水效果具有非常重要的意義。文章以改變?nèi)軞鈮毫�、釋放器傾角以及氣泡浮升高度為依托,研究了不同溶氣壓力、不同釋放器放置傾角以及氣泡上升的高度與生成氣泡尺寸之間的關(guān)系。首先對(duì)空氣在水中的溶解形式進(jìn)行了研究,并對(duì)空氣中氧氣和氮?dú)馊芙鈺r(shí)所占比重進(jìn)行了計(jì)算和對(duì)比,為提高溶氣效率提供了理論依據(jù);隨后使用熱力學(xué)和動(dòng)力學(xué)的方法研究了高壓溶氣水釋壓情況下微氣泡的成核過程以及其上升時(shí)的受力情況,得到了微氣泡成核過程中的能量變化以及氣泡上升過程中浮升速度與氣泡直徑的關(guān)系;在此基礎(chǔ)上,使用數(shù)值模擬的方法對(duì)兩種不同形式的TS-Ⅲ型溶氣釋放器在不同入口壓力的情況下其內(nèi)部流場進(jìn)行了對(duì)比分析,得出出口端添加孔板的溶氣釋放器內(nèi)部流場更均勻,更有利于微氣泡的生成,又分別對(duì)不同放置傾角的釋放器進(jìn)行了模擬分析,得出由于釋放器傾角的變化會(huì)導(dǎo)致氣相分布的不均勻從而影響氣泡的直徑;最后通過微氣泡拍攝的試驗(yàn)方法得到不同情況下的微氣泡圖像,并對(duì)氣泡尺寸進(jìn)行了測量。通過以上理論及試驗(yàn)研究,可以得到在TS型釋放器出口端添加孔板會(huì)使得微氣泡的尺寸更均勻;當(dāng)釋放器傾角相同時(shí),隨著溶氣壓力的增大,氣泡尺寸會(huì)逐漸減小,且在0.25~0.3MPa后趨于緩和;相同溶氣壓力下,隨著釋放器傾角由垂直變?yōu)閮A斜,氣泡直徑逐漸增大;當(dāng)溶氣壓力和釋放器傾角都一定時(shí),氣泡隨著高度的上升,直徑逐漸變大,當(dāng)高度大于25厘米時(shí),釋放器傾角的改變不會(huì)對(duì)氣泡直徑造成太大影響。
[Abstract]:Air flotation water purification technology is a kind of water purification method which can realize solid-liquid separation or liquid-liquid separation. It is widely used in petroleum industry, wool spinning industry, food industry and papermaking wastewater treatment and so on. The pressure-dissolved gas method is one of the methods to generate microbubbles in the air flotation water purification technology. The microbubbles generated by this method have the characteristics of fine size, uniform size and large quantity. The principle of water purification by pressure-dissolved gas floatation is that air is dissolved in water by making air molecules enter water intermolecular gaps or react with water molecules to form hydrates under high pressure. Gas molecules will rapidly gather to form a large number of tiny, uniform tiny bubbles, which combine with impurities in the water, and eventually carry impurities to the surface of the water to achieve the process of purifying the water. The size and quantity of microbubbles are the most important factors that affect the water purification effect by pressure dissolved gas flotation method. It is very important to study the process of dissolved gas in water, the process of bubble formation and the factors affecting bubble size. Based on changing the pressure of dissolved gas, the inclination of the releasing device and the height of bubble floating, the relationship between the bubble size and the different pressure of dissolved gas, the inclination angle of different emitter and the height of bubble rising are studied in this paper. Firstly, the dissolved form of air in water is studied, and the proportion of oxygen and nitrogen dissolved in air is calculated and compared, which provides a theoretical basis for improving the efficiency of dissolved gas. Then, the nucleation process of microbubbles and the forces acting on them when they rise are studied by thermodynamics and kinetics under the condition of high pressure dissolved gas, water release, and pressure release. The energy changes in the nucleation process of microbubbles and the relationship between the floating velocity and bubble diameter during bubble rising are obtained. The internal flow field of two different TS- 鈪，

本文編號(hào)：1945278