湿地水生植物厌氧发酵研究进展

Research Progress of Anaerobic Fermentation of Aquatic Plants from Wetland

摘要: 随着社会经济的发展，大量污染物如重金属等进入水体。人工湿地应运而生，在去除水体污染物方面表现出独特的优势，尤其适合发展中国家。湿地水生植物生物量大、有机物含量高，将其作为厌氧发酵的原料，一方面可以产出沼气作为生物能源，另一方面可以实现水生植物的有效处置，避免二次污染和生物质资源的浪费。基于前人关于水生植物厌氧发酵的研究结果，本文从湿地水生植物去污特点出发，总结水生植物生物质的特点，首次从是否受到金属污染的角度总结水生植物厌氧发酵产沼气方面的研究进展，归纳了不同水生植物厌氧发酵产气潜力，并对未来该技术的发展趋势进行了展望，为未来水生植物的处理处置和资源化提供参考。

Abstract: With the rapid development of industries, heavy metals wastewaters are directly or indirectly discharged into the environment increasingly, especially in developing countries. The removal of heavy metals from contaminated environment has become an urgent issue. Phytoremediation, which is defined as the use of plants to remove contaminants from contaminated environment, has attracted extensive attention. Many aquatic plants have been found to be efficient in removing contaminants. Nevertheless, excessive growth of aquatic plants is conversely able to cause various problems such as interfering with releasing unwanted odors, blocking daylight to the organisms and deoxygenation of water leading to the death of fish and other aquatic life forms. Moreover, the second pollution caused by the decayed plants is also the negative impact that should be avoided. Thus, cost-effective disposal and bio-resource utilization are required to build a sustainable treatment system. Aquatic plants harvested from wetland have large biomass and high organic content. Those biomasses can be used as raw materials of anaerobic fermentation to produce biogas as bioenergy and achieve the effective disposal of residues as well as avoid the secondary pollution. Basing on the previous studies on the anaerobic fermentation with non-contaminated or contaminated aquatic biomass as feedstocks, this article reviewed the mechanisms of decontami-nation and characteristics of aquatic plant biomass. The progress of anaerobic fermentation, using the metal contaminated aquatic plant or not, was then summarized for the first time. The future development of the technology was prospected. This review is expected to provide reference for disposal and reuse of aquatic plants in the future.