| Popis: |
The present study was conducted to investigate the heavy metals (HMS) removal from aqueous solutions in Complex ecosystem filter (CEF) with vermiculite substrate. Experimental results showed that the CEF was highly effectively in removal of HMS and the average removal rates of Cu2+, Zn2+, Pb2+ and Cd2+ were 81.60%, 80.55%, 83.20% and 62.21% respectively, under the hydraulic loading of 2.0m3/m2.d. The effluent concentration of HMS complied with the water quality standard of according to the Chinese Standard of Surface Water Environment Quality (GB3838-2002). The discernable trend is that roots accumulate significantly greater concentrations of metals than stems and leaves for all four metals. The Cu2+ concentration ranged from 4.11 to 8.23 mg/kg in the root tissues, while varied from 2.23 to 3.02 mg/kg in the stem tissues and from 1.32 to 1.85 mg/kg in the leaves tissues. The concentration of Cu2+ on vermiculite substrate was stable at about 30mg/kg, which suggested that the HMS assimilated by vermiculite substrate could be absorb by plant roots. Thus the adsorption capacity of vermiculite was effectively improved, as well as the work cycle of the CEF. |
