本文選題：吸附除磷 + 控菌��； 參考：《哈爾濱工業(yè)大學(xué)》2017年博士論文

【摘要】：隨著我國(guó)經(jīng)濟(jì)的騰飛,國(guó)民生活水平也得到了大幅提升,與人民生活息息相關(guān)的《生活飲用水衛(wèi)生標(biāo)準(zhǔn)》也日益嚴(yán)苛,作為基礎(chǔ)建設(shè)的城鎮(zhèn)飲用水水質(zhì)得到了很大的改善。尤其近十年隨著給水處理工藝的發(fā)展和更新,飲用水品質(zhì)在經(jīng)過給水處理的各個(gè)環(huán)節(jié)后得到了很大程度的改善。但是優(yōu)質(zhì)的水質(zhì)卻往往受到供水管網(wǎng)帶來(lái)的生物安全隱患的威脅,因此如何保持給水輸配途中的水質(zhì)成為了人們極度重視的問題。原水有機(jī)物殘留量為管網(wǎng)中的微生物提供了生長(zhǎng)的條件,水體呈現(xiàn)生物不穩(wěn)定,同時(shí)殘余有機(jī)物會(huì)快速消耗水中余氯嚴(yán)重地削弱了水體保證生物安全性的能力。針對(duì)給水生物安全問題,許多研究嘗試通過強(qiáng)化消毒等常規(guī)手段控制微生物生長(zhǎng),但是這往往會(huì)帶來(lái)消毒副產(chǎn)物生成,增加微生物抗藥性等一系列隱患。除此之外,限于給水水質(zhì)的嚴(yán)格要求,新開發(fā)的消毒劑還有待毒性測(cè)試。因此,給水生物安全問題仍待進(jìn)一步研究。與以往研究不同,本課題直接選擇關(guān)注生物穩(wěn)定性以控制飲用水生物安全,并且課題另辟蹊徑不采用常規(guī)控制可同化有機(jī)碳(AOC)而是采用除磷的方法控制生物穩(wěn)定性,為實(shí)現(xiàn)生物穩(wěn)定性提供了多重通道和選擇,這種“磷斷糧”的思路不僅僅是一種生物安全的保障方法,也為打破僅從碳源考量生物穩(wěn)定性的定勢(shì)思維,構(gòu)建新思路做出深入研究。為了解決給水中低濃度磷去除困難的實(shí)際問題,課題篩選不同種類的除磷吸附劑,最終確定了能與磷酸根具有超強(qiáng)結(jié)合能力的鑭基化合物作為功能組分。在此基礎(chǔ)上,通過靜電紡絲以及后續(xù)共沉淀等制備手段,得到了可以穩(wěn)定固著在聚丙烯腈高分子納米纖維中均勻分散的氫氧化鑭納米棒以及氧化鑭納米顆粒兩種材料。并且為了保證鑭基纖維優(yōu)秀的磷吸附能力,通過調(diào)整靜電紡絲的參數(shù)(電壓15-20 k V,環(huán)境濕度HR 30-50,電壓參數(shù)18-20 k V,PAN溶液濃度參數(shù)5 wt%-7 wt%,電紡速度參數(shù)0.1-1.0 m L/h),降低纖維直徑至100-200 nm,并且纖維直徑分布集中,最終得到了纖維結(jié)構(gòu)穩(wěn)定,形貌一致,直徑細(xì)小的基于氫氧化鑭納米棒以及氧化鑭納米顆粒的最優(yōu)紡絲材料。同時(shí),通過研究La(OH)_3/PAN纖維的制備過程,得到靜電紡絲過程可以保證金屬鹽活性位點(diǎn)負(fù)載具有優(yōu)異的分散性,并且電紡和共沉淀一起對(duì)金屬鹽的生長(zhǎng)有很好的調(diào)控作用,保證材料的一體性和吸附功能的最大化。聚丙烯腈在上述制備過程中,一方面作為支撐結(jié)構(gòu)為鑭離子和氫氧化鈉的作用提供接觸位點(diǎn),另一方面也控制了氫氧化鑭的成核與生長(zhǎng),使得氫氧化鑭的生長(zhǎng)由于位點(diǎn)的固定和限制而避免了大量納米棒的沉積,使得單分散式各向異性生長(zhǎng)的氫氧化鑭納米棒得以生成。La_2O_3/PAN纖維和La(OH)_3/PAN纖維對(duì)磷酸根優(yōu)異的吸附能力驗(yàn)證了鑭基化合物與磷酸根的超強(qiáng)作用能力。La_2O_3/PAN纖維的飽和吸附量為77.76 mg P/g(La),而與之相比,La(OH)_3/PAN纖維因?yàn)榻M分中高分散性La(OH)_3納米棒增加了反應(yīng)接觸的活性位點(diǎn)被證明具有更高的吸附能力,飽和吸附量達(dá)172.2 mg P/g(La)。并且La(OH)_3/PAN纖維具有超高效的吸附速率和對(duì)低濃度磷的超強(qiáng)捕捉能力,當(dāng)初始濃度為2 mg P/L時(shí),20 min即可迅速去除,去除率達(dá)到98.9%,這種突出的吸附性能保證了缺磷環(huán)境的實(shí)現(xiàn),解決了控菌目標(biāo)的瓶頸問題。除此之外,La(OH)_3/PAN纖維的穩(wěn)定性阻止了負(fù)載成分的泄漏,保證了功能組分La(OH)_3納米棒的使用安全,證明了這種納米材料在給水中應(yīng)用的安全性。在通過鑭進(jìn)行有效除磷的水體中,觀察典型陽(yáng)性與陰性菌的生長(zhǎng),證明缺乏磷元素的水體,對(duì)菌種的生長(zhǎng)有很好的控制效果,磷濃度在一定閾值下會(huì)抑制大腸桿菌和金黃色葡萄球菌的生長(zhǎng)。并通過自來(lái)水水體的實(shí)驗(yàn),證明通過“磷斷糧”的方法能夠很好的保證水質(zhì)生物安全穩(wěn)定性,經(jīng)過二次接觸污染的水體菌落個(gè)數(shù)并沒有增長(zhǎng),缺磷環(huán)境減少了微生物二次生長(zhǎng)的風(fēng)險(xiǎn)。最后,通過控制紡絲濕度,對(duì)靜電紡絲材料進(jìn)行改進(jìn),制備出能夠兼具過濾除菌和長(zhǎng)效控菌的鑭基濾膜。La(OH)_3/PAN濾膜在靜電紡絲中添加了鑭基鹽類,使得電紡纖維的平均直徑由140 nm降至110 nm,進(jìn)而降低了濾膜的孔徑,最大孔徑由0.90μm降至0.20μm。并且在后續(xù)共沉淀的過程中La(OH)_3納米棒的生長(zhǎng)提高了纖維的機(jī)械性能,同時(shí)濾膜表面由于鑭基鹽類負(fù)載得到的正電性也提高了菌體與膜表面的靜電引力作用,這些濾膜改進(jìn)增加了濾膜對(duì)菌體的截留能力。除此之外,由于La(OH)_3/PAN濾膜中功能組分鑭的添加,增加了對(duì)水中磷酸根的去除,厚度100μm以上的濾膜對(duì)磷的截留能力超過了97%,并且能夠完全截留濃度為107 CFU/m L的大腸桿菌。強(qiáng)化了濾出水的生物安全穩(wěn)定性,相比同樣具有過濾效果的濾膜,La(OH)_3/PAN濾膜能夠明顯控制微生物的二次生長(zhǎng)使得水體具有長(zhǎng)效的控菌能力。
[Abstract]:With the development of our country's economy, the national living standard has also been greatly improved. The sanitary standard for drinking water which is closely related to the people's life is also increasingly harsh. The water quality of urban drinking water has been greatly improved as a basic construction. In recent ten years, with the development and renewal of water treatment technology, the quality of drinking water has been given to the people. Every link of water treatment has been greatly improved, but the quality water quality is often threatened by the hidden danger of biological safety caused by the water supply network. So how to keep the water quality in the water supply and distribution has become a serious problem. The residual amount of organic matter in the original water provides the conditions for the growth of the microorganism in the pipe network. The water body presents biological instability, while residual organic substances will rapidly consume the residual chlorine in water to seriously weaken the water body's ability to ensure biological safety. In order to control the biological safety of water, many studies try to control microbial growth by means of intensive disinfection, but this will bring the production of disinfection by-products and increase the resistance of microorganisms. In addition to the strict requirements of water quality, the newly developed disinfectant still remains to be tested for toxicity. Therefore, the problem of biological safety in water supply remains to be further studied. Unlike previous studies, the subject has chosen to pay attention to biological stability to control the biological safety of drinking water. The regulation of assimilable organic carbon (AOC) is to control biological stability by means of phosphorus removal, and provides multiple channels and choices for the realization of biological stability. The idea of "phosphorus cutting" is not only a safeguard method for biological safety, but also a new way of thinking to break down a new thinking for the stability of the raw material only from the carbon source. In order to solve the practical problem of the difficulty in removing the low concentration of phosphorus in the water supply, we select different kinds of phosphorus removal adsorbents, and finally determine the functional component of the lanthanum compound, which can have super strong binding capacity with the phosphate root. On this basis, it can be stabilized by the means of electrostatic spinning and subsequent coprecipitation. Two materials are fixed in the polyacrylonitrile polymer nanofibers, which are evenly dispersed lanthanum hydroxide nanorods and two lanthanum oxide nanoparticles. In order to ensure the excellent phosphorus adsorption capacity of the lanthanum fiber, the parameters of the electrostatic spinning are adjusted (voltage 15-20 K V, ambient humidity HR 30-50, voltage parameter 18-20 K V, PAN solution concentration parameter 5 wt%-7 w) T%, the electrospinning speed parameter 0.1-1.0 m L/h), reduce the fiber diameter to 100-200 nm, and the fiber diameter distribution is concentrated. Finally, the fiber structure is stable, the morphology is consistent, and the diameter of the lanthanum oxide nanorods and lanthanum oxide nanoparticles are the best spinning materials. In the same time, the preparation process of La (OH) _3/PAN fiber was obtained and the static was obtained. The electrospinning process can ensure the excellent dispersibility of the metal salt active site load, and the electrospinning and co precipitation have a good control effect on the growth of metal salts, ensuring the integration of the materials and maximizing the adsorption function. In the preparation process, polyacrylonitrile is used as the supporting structure for lanthanum and sodium hydroxide on the one hand. The action provides contact sites, on the other hand, the nucleation and growth of lanthanum hydroxide is controlled. The growth of lanthanum hydroxide is prevented by the deposition of a large number of nanorods due to the fixed and restricted loci of lanthanum hydroxide. The monodisperse lanthanum hydroxide nanorods with monodisperse anisotropic growth are able to produce.La_2O_3/PAN fiber and La (OH) _3/PAN fiber to phosphoric acid. The excellent adsorption capacity of the root showed that the saturated adsorption capacity of.La_2O_3/PAN fiber was 77.76 mg P/g (La), and compared to that, the La (OH) _3/PAN fiber increased the reactive site of the reaction contact with the highly dispersed La (OH) _3 nanorods in the component and proved to have a higher adsorption capacity and saturated absorption. The attachment amounts to 172.2 mg P/g (La). And La (OH) _3/PAN fiber has super efficient adsorption rate and super strong capture ability to low concentration of phosphorus. When the initial concentration is 2 mg P/L, 20 min can be quickly removed and the removal rate reaches 98.9%. This outstanding adsorption performance ensures the realization of the phosphorus deficiency environment and solves the bottleneck problem of the target control. In addition, the stability of La (OH) _3/PAN fibers prevented the leakage of the load components and ensured the safety of the functional component La (OH) _3 nanorods. The safety of the nanomaterials used in water supply was proved. The growth of typical positive and negative bacteria was observed in the water body of effective phosphorus removal through lanthanum, and the water body lacking phosphorus was proved to be a water body. The growth of bacteria has a good control effect. Under a certain threshold, the concentration of phosphorus inhibits the growth of Escherichia coli and Staphylococcus aureus. Through the experiment of water body water, it is proved that the method of "phosphorus grain breaking" can guarantee the safety and stability of the water quality, and the number of colonies that have been contaminated by two times has not increased. Long, phosphorus deficient environment reduced the risk of two growth of microbes. Finally, by improving the spinning humidity and improving the electrospinning material, the lanthanum.La (OH) _3/PAN filter membrane, which could have both filtrating and long effect bacteria, was prepared to add lanthanum base salts in the electrospinning, and the average diameter of the electrospun fiber was reduced from 140 nm to 110 nm. The pore size of the filter membrane was reduced, the maximum aperture was reduced from 0.90 to 0.20 m to 0.20 Mu and the growth of La (OH) _3 nanorods during the subsequent coprecipitation improved the mechanical properties of the fiber. Meanwhile, the positive electricity of the membrane surface due to the lanthanide base salt load increased the electrostatic force of the bacteria and the membrane surface, and the filter membranes were improved. In addition to the addition of the functional component lanthanum in the La (OH) _3/PAN filter membrane, the removal of phosphate was increased by the addition of the functional component lanthanum in the filter membrane of the La (OH). The ability to intercept the phosphorus by the filter film above 100 mu m was more than 97%, and it could completely intercept the Escherichia coli with a concentration of 107 CFU/m L. The biological safety stability of the filtered effluent was enhanced. Compared with the same filtration membrane, the La (OH) _3/PAN membrane can control the two growth of microorganisms obviously, so that the water body has a long-term ability to control bacteria.
【學(xué)位授予單位】：哈爾濱工業(yè)大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2017
【分類號(hào)】：TU991.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 潘志輝;龔妍春;馬丙淳;葛祥軍;熊向源;;高分子納米材料基因載體研究進(jìn)展[J];生物技術(shù)通訊;2016年06期

2 潘敏;林旭萌;黃曉鳴;周可涵;張靈敏;;熱改性凹凸棒石吸附磷的試驗(yàn)研究[J];環(huán)境科技;2016年06期

3 尹朗;趙丹;張素佳;王海波;;飲用水管網(wǎng)生物膜細(xì)菌群落特征及其對(duì)腐蝕的影響[J];環(huán)境工程學(xué)報(bào);2016年10期

4 劉昌宏;張克峰;楊曉亮;宋武昌;賈瑞寶;;城市供水管網(wǎng)鐵穩(wěn)定性控制研究進(jìn)展[J];城鎮(zhèn)供水;2016年05期

5 梁冠華;胡沖;;一種新的污水管網(wǎng)腐蝕結(jié)構(gòu)修復(fù)方案[J];凈水技術(shù);2016年S1期

6 于曉芳;茅t挪，

本文編號(hào)：1997037