颗粒大小和几种预处理方法对浒苔厌氧发酵产沼气的影响

Effect on biogas production by the anaerobic fermentation of Enteromorpha prolifera of different granule sizes and with the methods of several pretreatments

近年来，由于生态环境变化和人为等因素，我国东部沿海遭受大规模浒苔侵袭的现象时有发生。开展浒苔的沼气发酵研究，一方面可以使这种优质的大型海藻类生物质原料被合理高效地利用，变废为宝；另一方面可以丰富沼气发酵原材料的种类，达到可再生能源开发的目的。该实验研究了不同颗粒大小（粗粒0．30～0．85mm、中粒0．15～0．30mm、细粒0．075～0．15mm）和碱预处理法、热预处理法、酸预处理法对浒苔在高温条件下发酵产沼气的影响。研究表明，当温度为50℃、初始pH为7、接种率为10％、料液总固形物（Ts）质量分数为8％的条件下厌氧发酵浒苔，粗粒组、中粒组和细粒组的浒苔挥发性固体（VS）产气率分别为386．9mL／g、434．4mL／g、436．5mL／g。其中，中粒组比粗粒组产气总量提高了12．26％，细粒组比中粒组产气总量提高了0．49％。这说明粒度越小越有利于提高浒苔沼气发酵的利用率；在相同发酵条件下（同上试验），碱、热、酸预处理组分别比未预处理组产气总量提高13．14％、11．39％和3．63％。其中，碱预处理组的VS产气率最高，为493．3mL／g，发酵过程中pH也较为稳定。因此，碱预处理法在提高浒苔厌氧发酵的沼气产量方面效果最佳。该研究的成果可为厌氧发酵浒苔生产沼气的工艺研究及生产提供参考。

In resent years, the phenomenon that China＇ s eastern coast was invaded by Enteromorpha prolifera because environmental change and anthropogenic factors occurred frequently. The significance of the study on fermentation of E. prolifera is in order to make the high-quality macroalgae biomass feedstock to be used rationally and efficiently, and to turn waste into treasure; On the other hand, it is a method to enrich types of raw materials of biogas in fermentation process to achieve the purpose of the development of renewable energy. In this paper, we research the effects on the biomass production by anaerobic fermentation of E. prolifera of different granule sizes（coarse particles 0.30 - 0.85 ram, medium-grained 0. 15 - 0.30 mm, fine-grained 0.075- 0.15 mm） and under different pretreatment methods （thermal pretreatment, dilute alkali pretreatment, acid pretreatment）. The results show that, biogas production rate of volatile solids （VS） in anaerobic fermentation process of using E. prolifera of different granule sizes mentioned above are 386.9 mL/ g, 434.4 mL/g and 436.5 mL/g. The production of biogas of E. prolifera at medium-grained showed 12.26% improvement than that at coarse particles. The experiments of E. prolifera at fine-grained showed 0.49% improvement than that at medium-grained. It shows that the smaller the particle size, the more improvement of utilization of E. prolifera in biogas production. It was found that, compared with the group without pretreatment, efficiency of biogas production of the three pretreated groups （ thermal, dilute alkali and acid pretreatment methods） showed 13.13% , 11.39% and 3.63% improvement when all the groups were under the same conditions（the same as the previous experiment）. Alkaline pretreatment method showed the best result, biogas production rate of volatile solids of this group is 493.3 mL/g. Alkaline pretreatment method improved biogas production efficiency in fermentation effectively, and the pH value in the process is relatively stable. This study tries to provide a theoretical reference to the research of biogas production process by anaerobic fermentation of E. prolifera.