本文選題：微生物水泥　切入點：膠結(jié)性能　出處：《東南大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：基于微生物誘導(dǎo)沉積礦化的微生物水泥能夠固結(jié)松散顆粒,且能耗低、污染少,在地基加固、揚(yáng)塵治理等領(lǐng)域可以解決傳統(tǒng)材料的一些弊端,如生產(chǎn)能耗高、化學(xué)毒性大等,是一種新型的可持續(xù)發(fā)展的膠凝材料。目前,生物碳酸鈣水泥研究最為廣泛,但主要針對其制備與應(yīng)用方面,而本課題通過篩選、培育出一種適合膠結(jié)用的磷酸鹽微生物,對特定底物作用并礦化沉積出生物磷酸鹽膠凝材料。同時從宏觀膠結(jié)性能、膠結(jié)界面性質(zhì)以及膠結(jié)物質(zhì)與顆粒間的微觀作用等方面對比了生物碳酸鹽水泥與生物磷酸鹽水泥的差異,并進(jìn)一步揭示了微生物水泥膠結(jié)作用的本質(zhì)。本文的主要研究成果如下：利用一種磷酸鹽礦化微生物,對特定底物作用并礦化合成出生物磷酸鹽沉積產(chǎn)物,分析表明產(chǎn)物為羥基磷灰石,微觀形貌呈納米球形顆粒的團(tuán)聚體。通過溶液體系內(nèi)生物磷酸鹽的沉積條件優(yōu)化研究,確定了生物磷酸鹽基本配方。對比研究不同微生物水泥膠結(jié)砂體可知,在砂體強(qiáng)度相近的條件下,生物碳酸鈣膠結(jié)砂體滲透系數(shù)與孔隙率均明顯高于其它實驗組,而砂體內(nèi)的膠結(jié)物質(zhì)含量卻低于其它實驗組,表明單位質(zhì)量的生物碳酸鈣的強(qiáng)度要高于其它微生物水泥。同時,砂體內(nèi)部微觀分析表明,各膠結(jié)物質(zhì)的沉積量與沉積分布方式均存在明顯差異。超聲振蕩脫粘實驗結(jié)果表明,生物碳酸鈣在玻璃片上沉積明顯,顆粒分布均勻且與玻璃片的界面結(jié)合作用較強(qiáng),其余依次為生物鳥糞石、生物磷酸鋇以及化學(xué)碳酸鈣,而生物磷酸鈣沉積效果最差,劃痕實驗結(jié)果進(jìn)一步驗證了上述規(guī)律。由界面結(jié)合強(qiáng)度與膠結(jié)物質(zhì)沉積量的關(guān)系可知,單位質(zhì)量的生物碳酸鈣的界面結(jié)合強(qiáng)度最大,這也與砂體的膠結(jié)強(qiáng)度規(guī)律吻合。利用X射線光電子能譜和核磁共振分析方法,研究了生物膠結(jié)物質(zhì)與松散砂顆粒間的作用,結(jié)果表明：在微生物礦化沉積中,石英砂顆粒中的Si原子所處的化學(xué)環(huán)境發(fā)生明顯改變,使其電子密度降低,表明生物膠結(jié)物質(zhì)與石英砂顆粒間形成了新的作用,而這種作用正是微生物水泥膠結(jié)的本質(zhì),而這種微觀作用的大小導(dǎo)致了不同微生物水泥膠結(jié)砂體的宏觀性能差異。
[Abstract]:Microbial cement based on microorganism induced deposition and mineralization can consolidate loose particles, low energy consumption and less pollution. In the fields of foundation reinforcement and dust treatment, some disadvantages of traditional materials can be solved, such as high energy consumption in production, high chemical toxicity and so on. It is a new kind of cementitious material for sustainable development. At present, the research of biological calcium carbonate cement is the most extensive, but it mainly aims at its preparation and application. Through screening, a phosphate microorganism suitable for cementation has been developed. Biophosphate cementitious materials are deposited on specific substrates and mineralized. At the same time, macroscopical cementing properties, The differences between biocarbonate cement and biophosphate cement were compared in terms of the properties of the cementation interface and the microcosmic interaction between the cementing materials and the particles. The main research results are as follows: using a phosphate mineralized microorganism, the biophosphate deposition products are synthesized by the interaction and mineralization of a specific substrate. The results showed that the product was hydroxyapatite, and the microcosmic morphology was nano-spherical agglomerate. The deposition conditions of biophosphate in solution system were optimized. The basic formula of biophosphate was determined. By comparing and studying different microbial cement cemented sand bodies, the permeability coefficient and porosity of biological calcium carbonate cemented sand body were obviously higher than those of other experimental groups under the condition of similar sand body strength. However, the cement content in sand is lower than that in other experimental groups, indicating that the strength of biocalcium carbonate per unit mass is higher than that of other microbial cement. The results of ultrasonic oscillation debonding experiment showed that the calcium carbonate deposited on the glass was obvious, the particle distribution was uniform, and the interface between the calcium carbonate and the glass was strong. The others are biological guano stone, biological barium phosphate and chemical calcium carbonate, while biocalcium phosphate deposit is the worst. The scratch test results further verify the above rule. The relationship between the interface bonding strength and the amount of cemented material deposition can be seen. The interfacial bonding strength of biocalcium carbonate per unit mass is the highest, which is consistent with the cementation strength of sand body. The interaction between biological cemented substance and loose sand particles is studied by means of X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) analysis. The results show that the chemical environment of Si atoms in quartz sand particles is changed obviously in microbial mineralized deposition, which results in the decrease of electron density, which indicates that there is a new interaction between biocynthesis and quartz sand particles. This kind of action is the essence of microbial cement cementing, and the microcosmic effect leads to the difference of macroscopic properties of different microorganism cement cementing sand bodies.
【學(xué)位授予單位】：東南大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TQ172.1

【相似文獻(xiàn)】

相關(guān)期刊論文 前3條

1 ;發(fā)布《食品添加劑　生物碳酸鈣》等二十六項行業(yè)標(biāo)準(zhǔn)[J];輕工標(biāo)準(zhǔn)與質(zhì)量;1999年06期

2 Nele DE BELIE;WANG Jianyun;Willem DE MUYNCK;Sandra MANSO BLANCO;Ignacio SEGURO P，

本文編號：1592940