Investigation On Immobilization Behavior Of Activitted Sludge On Carbon Fiber (CF)

Recently, membrane bioreactor (MBR) technology is more and more widely used in wastewater bio-treatment process, where the packed materials as a carrier of microorganism play an important role in MBR. Generally, all the packed materials type, the specific surface area, the pore volume and its distribution, etc, contributing to the bio-membrane will strongly affect the efficiency and the final result of wastewater treatment. The major commercial packed materials in market are usually composed of the traditional polymers such as PP, PE, PVC and PET/PBT, where the relevant research is mainly focus on the aspects of their specific surface area, structure and replace rate of bio-membrane. However, there still remain some shortages concerning with the rate formation, the amount and strength of bio-membrane.The current efforts are mainly placed on the following aspects such as how to increase the rate and the amount of bio-membrane, how to improve the replacement rate of bio-membrane, in the future so that to elevate the efficiency of wastewater treatment and to decrease the HRT of wastewater in MBR. The recent research works are mainly focused on the packed carrier concerning with bio-philic nature, and much development has been made where many scholars contribute greatly.Based on the above, the current theoretical and experimental investigation are carried out in order to certify the influences on the microorganism immobilization behavior of carbon fiber (CF), the growth promotion effects of carbon materials to microorganism and the application future of CF as a new kind of packedbio-materials for MBR. The thesis is divided into 5 chapters:'the 1st chapter is the introduction to MBR technology and CF; the 2nd chapter is concerning with the experiments of surface treatment of CF, the immobilization behavior of CF to microorganism, the XPS characterization on surface functional groups and the influence factors on bio-philic nature of CF; the 3rd chapter is related to the investigation on the microorganism growth promotion effect by means of calculating the wavelength of light derived from the valence-electron stimulated emissions in graphite crystal and the promotion experiments on microorganism growth; the 4th chapter is placed on the discussion of CF applications as a new kind of packed bio-materials in MBR.Through the above theoretical and experimental investigation, it is indicated that (1) the surface functional groups of C-C , C — COOH and C=O band strongly affect the microorganism immobilization behavior on PAN-based CF; (2) the microorganism immobilization behavior could be controlled by the surface treatment on varying surface morphology and functional groups; (3) it is suggested that the growth promotion effect on microorganism could be concerned with the coherent interference existing between the light derived from the valence-electron stimulated emissions in graphite crystal and the bio-photon fields; (4) CF could be used as a new kind of efficiency bio-carrier packed materials in MBR process for its fast bio-membrane formation and significant amount of sludge carrying capacity.