本文選題：多級進(jìn)氣 + 光生物反應(yīng)器　； 參考：《中國海洋大學(xué)》2015年碩士論文

【摘要】：微藻在生物能源、環(huán)境保護(hù)、食品、保健品及醫(yī)藥等領(lǐng)域具有巨大的潛在應(yīng)用價值。然而微藻培養(yǎng)的反應(yīng)器性能不佳一直制約著微藻規(guī)�；l(fā)展。傳統(tǒng)光生物反應(yīng)器的優(yōu)化設(shè)計及放大方法研發(fā)周期長,成本大,不能全面研究反應(yīng)器內(nèi)部的流場特性。近年利用計算流體力學(xué)(CFD)進(jìn)行微藻培養(yǎng)光生物反應(yīng)器研究盡管有很多彌補傳統(tǒng)方法的優(yōu)點,但因剛剛興起仍存在大量空白。本文針對微藻培養(yǎng)領(lǐng)域主流的平板式光生物反應(yīng)器,在前人基礎(chǔ)上提出了多級進(jìn)氣多節(jié)隔板反應(yīng)器的結(jié)構(gòu)設(shè)想,并利用CFD技術(shù)對該新型反應(yīng)器的混合、傳質(zhì)和傳光特性進(jìn)行了相對系統(tǒng)研究,具體結(jié)果如下。首先,采用ANSYS Fluent商業(yè)軟件,構(gòu)建了多級進(jìn)氣多節(jié)隔板平板式反應(yīng)器計算模型,采用Eulerian-Eulerian多相流模型和PBM模型進(jìn)行耦合模擬計算,模擬結(jié)果與實驗測量結(jié)果對比驗證了本文所建立模擬模型的可行性與可靠性。多級進(jìn)氣反應(yīng)器上段和中段隔板局部氣含率、局部液相矢量速度受通氣率的影響較大,其下段性能參數(shù)受通氣率的影響較�。浩渫膭幽茉谏簠^(qū)呈雙峰結(jié)構(gòu)分布,在降液區(qū)湍動能分布較為平緩。而后,通過CFD模擬計算對比了普通(A)、多節(jié)隔板(B)、多級進(jìn)氣多節(jié)隔板(C)三種反應(yīng)器的流場流動與傳質(zhì)特性。結(jié)果表明,在一定的通氣率下多級進(jìn)氣反應(yīng)器在氣含率、液體平均速度、湍動能、液相傳質(zhì)系數(shù)等性能評價參數(shù)較前兩種反應(yīng)器分別有很大提高,其中通氣率在0.8 vvm時,反應(yīng)器C中的氣含率較反應(yīng)器A、B分別提升52.63%和39.11%,通氣率在0.4 vvm和0.6 vvm時,反應(yīng)器C的kLa值較反應(yīng)器B分別提高36.16%和11.27%。進(jìn)而,利用多相流模型和PBM模型耦合的方法,對影響該新型反應(yīng)器混合傳動、傳質(zhì)性能的氣泡特性進(jìn)行了進(jìn)一步的研究。反應(yīng)器氣泡直徑分布等氣泡特性參數(shù)結(jié)果表明,在反應(yīng)器高度390 mm上,反應(yīng)器C的Bin-0體積分?jǐn)?shù)較反應(yīng)器B降低了32.79%：反應(yīng)器B內(nèi)大于6 mm氣泡直徑體積占總體積分?jǐn)?shù)為8.58%,而反應(yīng)器C為0.54%。上述結(jié)果表明反應(yīng)器C能有效降低氣泡聚并,其中氣泡分布良好,這將有利于相間傳質(zhì)。結(jié)合CFD模擬計算結(jié)果與藻類傳光規(guī)律,本文對比分析了三種反應(yīng)器的傳光特性。結(jié)果表明,反應(yīng)器C較反應(yīng)器B增加了反應(yīng)器內(nèi)光照方向徑向混合強度,反應(yīng)器C較反應(yīng)器B在光區(qū)的徑向速度提高了28.25%,在光區(qū)平均停留的時間有所縮短,光暗循環(huán)的周期也相對比反應(yīng)器B縮短了]9.63%,加快反應(yīng)器內(nèi)微藻的在光區(qū)和暗區(qū)的光暗循環(huán)頻率,加快了微藻閃光效應(yīng),有助于微藻生長。最后,通過CFD模擬對反應(yīng)器C的內(nèi)部結(jié)構(gòu)參數(shù)(隔板的位置(Ar/Ad)、隔板上沿距液面的距離(h0)和隔板間隙的長度(D))進(jìn)行了優(yōu)化分析。結(jié)果表明,液相體積傳質(zhì)系數(shù)和光區(qū)的徑向速度隨Ar/Ad值的增大而降低,整體混合情況在Ar/Ad為0.5時效果較好；整體的混合性能和光區(qū)的徑向速度隨h0增加而增加,當(dāng)ho為40 mm時反應(yīng)器的傳質(zhì)性能較好；隨著隔板間隙的距離增加,ATK和光區(qū)徑向速度逐漸增加,而反應(yīng)器的傳質(zhì)性能在隔板間隙為15mm時達(dá)到最大。綜上所述,反應(yīng)器C較其他兩種反應(yīng)器在混合、傳動和傳質(zhì)性能上有很大的提升,降低反應(yīng)器內(nèi)氣泡的聚并現(xiàn)象,優(yōu)化氣泡分布,提高閃光效應(yīng)。反應(yīng)器內(nèi)部結(jié)構(gòu)參數(shù)對混合、傳質(zhì)、傳光的影響分析結(jié)構(gòu),為平板生物反應(yīng)器的設(shè)計及優(yōu)化提供新思路和方向。
[Abstract]:Microalgae have great potential application value in the fields of biological energy, environmental protection, food, health care products and medicine. However, the poor performance of microalgae has been restricting the development of microalgae. The optimization design and enlargement of the traditional photo bioreactor have long period and high cost, and can not fully study the internal reaction inside the reactor. In recent years, the study of microalgae culture photo bioreactor using computational fluid dynamics (CFD) has many advantages to make up the traditional methods, but there are still a lot of blanks due to the rising of the traditional method. In this paper, a multilevel intake multi section baffle reaction is proposed on the basis of the mainstream plate type bioreactor in the field of microalgae culture. The structure of the device is envisaged, and the CFD technology is used to study the mixing, mass transfer and transmission characteristics of the new type reactor. The specific results are as follows. First, the multi intake multi section baffle plate reactor calculation model is constructed with the ANSYS Fluent commercial software, and the Eulerian-Eulerian multiphase flow model and the PBM model are used for coupling. The simulation results compare with the experimental results to verify the feasibility and reliability of the simulation model established in this paper. The local gas holdup in the upper and middle section of the multistage inlet reactor is greatly influenced by the ventilation rate, and its lower performance parameters are less affected by the ventilation rate: its turbulent kinetic energy is in the lift. The distribution of the region is in Shuangfeng, and the turbulent kinetic energy distribution in the drop zone is relatively slow. Then, the flow flow and mass transfer characteristics of three kinds of reactors are compared by CFD simulation. The results show that the gas holdup, the mean velocity and turbulence of the multistage intake reactor at a certain ventilation rate are at a certain rate of ventilation. The performance evaluation parameters such as the mass transfer coefficient of liquid phase are greatly improved than those of the first two reactors. When the ventilation rate is 0.8 VVM, the gas holdup in the reactor C is 52.63% and 39.11% higher than that of the reactor A, B respectively. When the ventilation rate is 0.4 VVM and 0.6 VVM, the kLa value of the reactor C is increased by 36.16% and 11.27%., respectively than the counter reactor B, and the multiphase flow is used. The coupling method of the model and PBM model is used to further study the bubble characteristics that affect the mass transfer performance of the new reactor. The bubble diameter distribution and other bubble characteristic parameters show that the Bin-0 body integral of the reactor C is 32.79% lower than that of the reactor B at the reactor height of 390: the reactor B is more than 6 within the reactor B. The total volume fraction of the MM bubble diameter is 8.58%, and the C of the reactor is 0.54%.. The result shows that the reactor C can effectively reduce the bubble aggregation and the bubble distribution is good. This will be beneficial to the mass transfer. The light transmission characteristics of the three reactors are compared and analyzed in this paper. The results show that the reaction is a reaction. The results show that the reaction is a reaction. The radial mixing intensity in the light direction in the reactor is increased by the device C than the reactor B, the radial velocity of the reactor C is increased by 28.25% compared with the reactor B in the light region. The time of the average stay in the light region is shortened, and the period of the light dark cycle is also shorter than the B of the reactor B, and the light dark circulation frequency of microalgae in the light and dark areas of the reactor is accelerated. At last, the internal structure parameters (Ar/Ad) of the reactor C (Ar/Ad), the distance from the liquid surface (H0) and the length of the gap between the separators (D) were optimized through the simulation of the internal structure parameters of the reactor. The results showed that the mass transfer coefficient of the liquid phase and the radial velocity of the light region increased with the Ar/Ad value. The overall mixing situation is better when Ar/Ad is 0.5. The overall mixing performance and the radial velocity of the light region increase with the increase of H0. When the ho is 40 mm, the mass transfer performance is better. With the gap gap increasing, the radial velocity of ATK and the light region increases gradually, while the mass transfer performance of the reactor is 15mm when the gap gap is 15mm. To sum up, the reactor C is better than the other two kinds of reactors in mixing, transmission and mass transfer performance is greatly improved, reducing the coalescence of bubbles in the reactor, optimizing the bubble distribution and improving the flash effect. The structure parameters of the reactor internal structure are analyzed for the influence of mixing, mass transfer and transmission, and the design of the plate bioreactor and the design of the reactor. The optimization provides new ideas and directions.

【學(xué)位授予單位】：中國海洋大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：Q949.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 陶藝;袁壽其;張金鳳;張帆;陶建平;;渣漿泵葉輪磨損的數(shù)值模擬及試驗[J];農(nóng)業(yè)工程學(xué)報;2014年21期

2 郭欣;孫德宇;李建隆;黃青山;;平板氣升環(huán)流式光生物反應(yīng)器中氣泡特性的圖像法分析[J];計算機與應(yīng)用化學(xué);2014年06期

3 黃建科;康少鋒;李元廣;李偉;;蛋白核小球藻的光衰減模型及藻細(xì)胞受光特性參數(shù)的模擬[J];過程工程學(xué)報;2014年02期

4 劉建國;龍元薷;黃園;龐通;林偉;李凌;;微藻生物柴油研究現(xiàn)狀與發(fā)展策略[J];海洋科學(xué);2013年10期

5 韓佳偉;趙春江;楊信廷;錢建平;邢斌;范蓓蕾;;基于CFD數(shù)值模擬的冷藏車節(jié)能組合方式比較[J];農(nóng)業(yè)工程學(xué)報;2013年19期

6 程軍;莊良;黃云;孫晶;周俊虎;岑可法;;平板式微藻光反應(yīng)器的流場優(yōu)化及閃光效應(yīng)[J];浙江大學(xué)學(xué)報(工學(xué)版);2013年11期

7 李紹果;薛天艷;齊濤;劉長厚;;分段進(jìn)氣多級環(huán)流反應(yīng)器流動與傳質(zhì)特性研究[J];化學(xué)工程;2013年07期

8 王琴;符笳茵;應(yīng)月;黎奇欣;黃嘉玲;;廢水養(yǎng)殖高油微藻的研究進(jìn)展[J];現(xiàn)代食品科技;2013年06期

9 王冬琴;譚瑜;盧虹玉;蘇偉明;胡雪瓊;李雁群;;微藻生物活性物質(zhì)在食品工業(yè)中的應(yīng)用進(jìn)展[J];現(xiàn)代食品科技;2013年05期

10 岳麗宏;郝欣欣;;平板式光生物反應(yīng)器內(nèi)有效光分布研究[J];青島理工大學(xué)學(xué)報;2012年05期

，

本文編號：1892491