【摘要】 通过对污水生物污泥在不同碳氮比(70、140和210)基质条件下的连续培养,研究生物污泥增脂的历程及其对后续制取生物柴油的影响,并考察在此过程中污泥脱水性能的变化。结果表明:在不同C/N值条件下培养的生物污泥制取生物柴油过程中,生物柴油产量均在培养5 d时达到最大,且碳氮比值越高则生物柴油产量越大,碳氮比值为70、140和210条件下培养的生物污泥原位酯化制取的生物柴油产率分别为4.65%、5.53%、6.59%,为原始污泥制取生物柴油产率的3.58、4.25和5.07倍;且此时污泥中各脂肪酸含量均发生了变化,其中油酸含量明显增加,大约占脂肪酸总量的40%。与此同时,与原始污泥相比,高碳氮比基质培养后的污泥中主导微生物倾向于酵母菌,且污泥的毛细吸水时间从第5天开始迅速升高。综上所述,C/N值为210条件下培养5 d时的生物污泥制取生物柴油的产率最大、脱水预处理最易实现。更多还原

【Abstract】 The effect of different C / N ratios( C / N = 70,140 and 210) on the lipid accumulation and the subsequent biodiesel yield of activated sludge in the process of continuous cultivation was studied. Meanwhile the dewatering characteristic of the cultivated sludge was investigated. The results showed that the yield of the fatty acid methyl esters( biodiesel) was enhanced via cultivating the activated sludge at different C / N ratios,and a higher biodiesel yield happened under the cultivation of the higher C / N ratio. The maximum biodiesel yield of all the cultivated sludge was achieved on the 5th day of the sludge cultivation,which were 4. 65%,5. 53% and 6. 59% respectively when the C / N ratios were 70,140 and210. The above values were 3. 58,4. 25 and 5. 07 times those of the raw biological sludge. Moreover the content of the fatty acids in the cultivated sludge at different C / N ratios was changed and the content of oleic acid was remarkably increased,accounting for about 40% of the total fatty acids. Compared with the raw biological sludge,the dominant microbes in the sludge cultivated at high C / N ratios were apt to be yeast and the capillary suction time of the sludge began to increase rapidly from 5th day of the cultivation.In summary,when the biological sludge was cultivated at the C / N ratio of 210 for five days,the biodiesel yield reached the maximum,and the pretreatment process of dehydration was easier for the sludge.更多还原