Chemosphere ( IF 5.778 ) Pub Date : 2021-02-15 , DOI: 10.1016/j.chemosphere.2021.129954 Lu Li; Zhouyang Li; Kang Song; Yilu Gu; Xiaofeng Gao; Xiaoli Zhao
The harvesting of algal sludge from eutrophic lakes, including the large quantity of organic matters, has the potential to be used as valuable products through the process of resource recovery. This study investigates the fatty acid production potential from algal sludge via anaerobic fermentation under different pH values. The results indicated that the recovery of short-chain fatty acids (SCFAs) was the highest (3269.25 ± 32.89 mg·COD/L) at pH 11 after 7 days of fermentation. The SCFAs concentration at pH value 11 was 6.24, 1.27, 4.90, and 0.53 times higher compared with that at pH value 3, 5, 7, and 9, respectively. The SCFAs production was continually increased from day 1 to day 7 at pH value 7, 9, and 11. Much fewer middle- and long-chain fatty acids were produced compared with SCFAs. Gross.
fatty acid production was the highest at pH 11. The concentrations of soluble protein and polysaccharide were the highest at pH 11, implying that the disruption of algal cells could have a high value at pH 11. The polysaccharide concentration was the lowest at pH 7. The fluorescence excitation-emission matrix profile implied that the disruption of algal cells was the greatest at pH 11. Methane production was greatest at pH 7 and 9. Overall, the results of this study revealed that a pH of 11 was optimal for the recovery of SCFAs from algal sludge due to the higher cell disruption, suitable ORP condition for SCFAs production and inhibition of methanogens.
从富营养化湖泊中收获藻类污泥（包括大量有机物），有可能在资源回收过程中用作有价值的产品。这项研究调查了在不同pH值下通过厌氧发酵藻类污泥产生脂肪酸的潜力。结果表明，发酵7天后，pH 11时，短链脂肪酸的回收率最高（3269.25±32.89 mg·COD / L）。pH值为11时的SCFA浓度分别是pH值为3、5、7和9时的6.24、1.27、4.90和0.53倍。在pH值7、9和11的第1天到第7天，SCFA的产量持续增加。与SCFA相比，产生的中链和长链脂肪酸要少得多。总的。