生物炭及其金属改性材料脱除水体磷酸盐研究进展

Research progress on removal of phosphate from aqueous solution by biochar and its metal modified materials

磷素是水体富营养化主要限制性因子,控制河流湖泊中磷酸盐具有重要意义.吸附法是一种经济、高效和操作简单的除磷方法,但其应用的关键在于选择合适的吸附材料.将生物炭应用于水体磷酸盐脱除,一方面可为农林废弃物、畜禽粪便、活性污泥、入侵植物的处理提供新途径,另一方面吸磷后的生物炭还能用于土壤改良.然而,生物炭脱除水体磷酸盐虽具有以上优势,但也存在实际应用困难的问题.回顾了国内外生物炭脱除磷酸盐的相关研究成果.总结了生物炭脱除磷酸盐的能力;解释了常规生物炭和金属改性生物炭的脱磷机理;分析了溶液pH值、温度、共存离子、初始磷酸盐浓度以及其他反应条件对生物炭脱除磷酸盐的影响,简述了生物炭解吸磷酸盐的特性.最后提出应深入研究生物炭金属改性机理和脱除磷酸盐的机理,开展生物炭吸附磷素形态组成复杂的自然水体或吸附柱试验,加强吸磷生物炭用作土壤改良的研究及风险评价,并对生物炭制造成本做出估算,争取早日实现生物炭污染水体脱磷的产业化应用.

Phosphorus is the main limiting factor of eutrophication. How to control the phosphate concentration in rivers and lakes is of great significance to control eutrophication. it is considered that adsorption is an economical, efficient and simple phosphorus removal method. However, how to select the appropriate adsorption material is the key to its application. The application of biochar to the removal of phosphate from water can provide a new way for the treatment of agricultural and forestry waste, livestock manure, activated sludge and invasive plants. The phosphate-absorbing biochar can be used to improve soil improvement. Methodology is of highly advantageous but difficult in phosphate removal from practical waste water. The current paper reviewed domestic and international research results pertaining to phosphate removal by biochar. The ability of biochar to remove phosphate was summarized. The mechanism of phosphate removal by biochar or metal modified biochar was explained. The effects of pH, temperature, co-existing ion, initial phosphate concentration and other reaction conditions on the removal of phosphate by biochar were analyzed, and the characteristics of the desorption of phosphate were briefly described. Lastly, to realize the industrial application of biochar in contaminated water, it was pointed out that the mechanism of modification and phosphate removal be further researched, and experiments should be conducted using natural water bodies with complex forms of phosphorus or adsorption columns, and the research and risk assessment about phosphate-absorbing biochar as a soil amendment should be further strengthened, and the cost of biochar manufacturing should be estimated.