基于矿化垃圾的生态护岸强化脱氮基质的可行性研究

FEASIBILITY OF A NEW AGED-REFUSE-BASED SUBSTRATE MATERIAL OF ECOLOGICAL EMBANKMENT FOR ENHANCED REMOVAL OF NITROGEN

生态护岸是目前河、湖治理与修复过程中削减面源氮营养盐的重要措施之一。而筛选高效、低耗的生态护岸基质材料是其关键环节。通过优化复配矿化垃圾、沸石和砾石,研制一种基于矿化垃圾的新型强化脱氮生态护岸基质材料,并从其透水和持水性、抗剪、抗压和抗冲刷性、生态安全性、植被相容性和氮削减特性等方面对该材料进行了性能评定。结果表明:该新型基质材料的透水(渗透系数为1.31~2.55 cm/min)、持水(持水度为5.87%~8.02%)、抗剪(抗剪强度大于60 kPa)、抗压(抗压强度大于380 kPa)以及抗冲刷的性能均满足生态护岸基质材料的要求;发光细菌毒理实验证实其生态安全性;该材料适于护岸植被芦苇、鸢尾和麦冬的生长;具有优良的氮削减性能(氨氮和总氮的削减率分别为95%和70%)。静态经济评价表明,该材料具有明显的成本优势。该新型材料的研制对于生态护岸脱氮功能拓展以及解决河湖治理中面临的"氮超标"问题具有现实意义。

Ecological embankment is considered as one of the effective measures to control non-point nitrogen pollution in water environment remediation, and the key step is to screen out substrate-material with high-efficiency and low-cost. This research developed new aged-refuse-based embankment material and its performance was evaluated systematically in terms of water permeability and water holding capacity, shearing and compressive property, ecological safety, vegetation compatibility, as well as removal of nitrogen. Results indicated that the permeability coefficient and the retention were 1.31 ~2.55 cm/min and 5.87% ~ 8.02% , respectively; the shear and compressive strength were separately greater than 60 kPa and 380 kPa; toxicology experiment of luminescent bacteria confirmed its ecological safety; reed, iris and liriope were good candidates for vegetation; the removal efficiency of ammonia nitrogen, total nitrogen was 95% and 70% , respectively. Thus, the material could meet the requirements of ecological embankment. Notably, it was also with extremely low cost. This research is of great significance to expand the pollutant-removal function of ecological embankment, and solve the problem of hindering non-point nitrogen.