發(fā)布時(shí)間：2020-12-17 03:13

　　面對(duì)當(dāng)今世界對(duì)可再生能源日益增長(zhǎng)的需求,氫氣作為一種環(huán)保、高能可再生能源,可保障未來(lái)的能源安全。木質(zhì)纖維素生物質(zhì)可轉(zhuǎn)化并產(chǎn)生能源和化學(xué)品,替代化石燃料滿(mǎn)足能源需求,同時(shí)減少二氧化碳的大氣排放,是一類(lèi)環(huán)境友好型的可再生資源。本論文主要關(guān)注甜高粱秸稈的厭氧生物發(fā)酵產(chǎn)氫氣和揮發(fā)性脂肪酸。由于在微生物發(fā)酵過(guò)程中,甜高粱秸稈所含的纖維素和半纖維等結(jié)構(gòu)性多糖難以被有效利用,如何提高結(jié)構(gòu)性多糖的利用度和發(fā)酵產(chǎn)物的產(chǎn)量,成為本論文研究重點(diǎn)。共培養(yǎng)Clostridium thermocellum和Clostridium thermosaccharolyticum發(fā)酵甜高粱秸稈,當(dāng)?shù)孜餄舛葹?g/L,接種C.thermocell.m培養(yǎng)24h之后,以1:1比例接種C.thermosaccharolyticum可以獲得最大的氫氣和揮發(fā)性脂肪酸產(chǎn)量,氫氣產(chǎn)量為5.1 mmol/g-substrate,乙酸為1.27g/L,丁酸為1.05g/L。相比于單菌培養(yǎng)氫氣、乙酸和丁酸的產(chǎn)量分別提高了55%、9%、10%。通過(guò)C.thermosaccharaolyticum兩步發(fā)酵結(jié)合稀酸處理第一步發(fā)酵殘?jiān)男鹿に?進(jìn)一... 

【文章來(lái)源】：中國(guó)科學(xué)院大學(xué)(中國(guó)科學(xué)院過(guò)程工程研究所)北京市

【文章頁(yè)數(shù)】：129 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
Abstract
摘要
1. Introduction
    1.1 Bio-hydrogen and volatile fatty acid
        1.1.1 Bio-hydrogen
        1.1.2 Volatile fatty acid
        1.1.3 Biosynthetic pathways
        1.1.4 Process parameters for hydrogen and VFA fermentation
            1.1.4.1 Temperature
            1.1.4.2 pH
            1.1.4.3 Hydrogen partial pressure
    1.2 Lignocellulosic biomass for hydrogen and VFA production
        1.2.1 Substrates
        1.2.2 Pretreatment of substrates
            1.2.2.1 Physical pretreatments
            1.2.2.2 Chemical pretreatments
            1.2.2.3 Biological pretreatments
            1.2.2.4 Combined pretreatments
            1.2.2.5 Inhibitory compounds
    1.3 Sweet sorghum stalk
        1.3.1 Potential uses of sweet sorghum
            1.3.1.1 Food/feed
            1.3.1.2 Biofuel feedstock
            1.3.1.3 Sweet sorghum biorefinery
    1.4 Aims and objectives
2. Coproduction of hydrogen and VFA by thermophilic fermentation fromco-culture of C. thermocellum and C. thermosaccharolyticum
    2.1 Introduction
    2.2 Experimental methodology
        2.2.1 Materials and chemicals
        2.2.2 Microorganisms and culture condition
        2.2.3 Experimental design
        2.2.4 Analytical methods
    2.3 Results and discussion
        2.3.1 Effect of the inoculation ratio of C. thermosaccharolyticum to C.thermocellum on hydrogen and VFA production
        2.3.2 Effect of substrate concentration to optimize the maximum conversion forco-culture of C. thermosaccharolyticum to C. thermocellum on hydrogenand VFA
        2.3.3 Optimization of inoculation time gap between C. thermosaccharolyticumfollowed by C. thermocellum
        2.3.4 Hydrogen and VFA production from single-culture of C.thermosaccharolyticum and co-culture of C. thermocellum and C.thermosaccharolyticum
    2.4 Conclusions
3. Coproduction of hydrogen and VFA by two-step fermentation with dilute acidtreatment in between
    3.1 Introduction
    3.2 Experimental methodology
        3.2.1 Materials and chemicals
        3.2.2 Microorganism and culture conditions
st step fermentation">        3.2.3 1^st step fermentation
nd step fermentation">        3.2.4 Dilute acid treatment and 2^nd step fermentation
        3.2.5 Analytical methods
    3.3 Results and discussion
st step dark fermentation of sweet sorghum stalk by C.thermosaccharolyticum">        3.3.1 1^st step dark fermentation of sweet sorghum stalk by C.thermosaccharolyticum
st step fermentation">        3.3.2 Acid treatment on residual biomass after 1^st step fermentation
        3.3.3 Effect of acid concentration with different reaction temperature on residualbiomass for hydrogen, acetic acid and butyric acid production
        3.3.4 Total hydrogen and VFA production from one step fermentation and twostep fermentation with dilute acid treatment in between
    3.4 Conclusion
4. Coproduction of hydrogen and volatile fatty acid by two-step fermentationintegrated with alkali and enzyme treatment in between
    4.1 Introduction
    4.2 Experimental methodology
        4.2.1 Materials and chemicals
        4.2.2 Microorganism and culture conditions
st step fermentation">        4.2.3 1^st step fermentation
nd step fermentation">        4.2.4 Alkali treatment followed by enzyme hydrolysis and 2^nd step fermentation
        4.2.5 Analytical methods
    4.3 Results and discussion
st step dark fermentation by C.thermosaccharolyticum">        4.3.1 Fermentability of sweet sorghum stalk in 1^st step dark fermentation by C.thermosaccharolyticum
st step fermentation: effect ofNaOH loading and reaction temperature on composition of residualbiomass">        4.3.2 Alkali treatment on residual biomass after 1^st step fermentation: effect ofNaOH loading and reaction temperature on composition of residualbiomass
st step fermentation">        4.3.3 Effect of NaOH loading and reaction temperature on enzymatic digestibilityof residual substrate from 1^st step fermentation
        4.3.4 Effect of NaOH concentration with different reaction temperature onresidual biomass for hydrogen, acetic acid and butyric acid production
        4.3.5 Total hydrogen and VFA yields in one step and two step fermentation withNaOH followed by cellulase enzyme treatment in between
    4.4 Comparison of hydrogen and organic acid production performance for differenttreatment methods
    4.5 Techno-economic comparison of different anaerobic dark fermentation processes
    4.6 Conclusion
5. Conclusions and prospective
    5.1 Conclusion
    5.2 Novelty
    5.3 Prospective
List of abbreviations
References
Acknowledgements
Curriculum vitae



本文編號(hào)：2921310