On-Site Treatment Of Sediment From Polluted River And Lake And Its Removal Ability Of Nitrogen And Phosphorus

The sediment of polluted rivers and lakes has become the endogenous pollution and the unwise treatment may lead to more serious environmental pollution and waste of resources. With the development of the society and economics, water pollution has become one of the most important problems. And the sediment treatment of polluted rivers and lakes has also become more difficult than before, because of its complexity and poor self-purification ability. Ecological restoration will be a hot zone for sediments treatment and has been widely considered as the best way to solve the sediments pollution. But the shortcoming of ecological restoration for sediments is inefficient. This research makes a combination for dredge and on-site treatment. Use the sediments by dredged to build an ecological revetment. The dredge makes sure the high efficiency of sediments treatment and the on-site treatment system makes sediment harmless and resources reuse.The on-site treatment was established in an artificial lake near Yi Tong River of Changchun City in Jilin Province, China. Use willow(Salix matsudana Koidz) as the experimental plant. Mix sediments with clinker by different volume ratio. This research tries to discuss how the different volume ratio and different time affect the willows growth and physical and chemical properties of sediments. Here comes the result:(1)From the biomass we can easily see that the sediments combined with the clinker have positive effect on the growth of willow. By October,in the fifth team, the biomass of root is 12.00g;The biomass of steam is 56.20 g and the biomass of leaves is 19.18 g. Compare with the team without the clinker, the team mixed with the most of clinker has increase by 363.32%、950.47%、230.12% in the roots,steams and the leaves. By this we can see the mass of clinker mixed with sediments affect the willow’s growth.(2)The accumulation of N and P in willow of different team doesn’t have a big difference. But in different part, the accumulation of N and P has a big different. The accumulation of N in steam is higher than other parts. 90% N store in steam. The leaves will fade away every year and the N in the leaves will follow the leaves go back into the sediments but the steam will not. So the willow has a good absorb for N. But for P, the willow doesn’t means too much.(3)By October, the willows has absorbed 56.07g、49.02g、51.50g、54.40 g of nitrogen and 3.76 g 、 1.22 g 、 7.74 g 、 4.80 g of phosphorus in non-clinker, 0.25 clinker,0.5 clinker and 0.75 clinker. There is not too much different in nitrogen’s absorbing among all the teams. Although there is some different in phosphorus’ s absorbing but the use of phosphorus of willows is not the main way to move P out of the sediments. Considered the biomass of the willows, the volume ratio of 1 to 1 for clinkers and sediments is the most efficiency ratio.The on-site treatment system tries to find a way using the concept of ecological restoration to settle the problem of sediment after dredging. Mix sediments with the clinkers and use the wells to apply the water for system then plant willow in it. The on-site treatment system not only tries to reiterate the sediments but also builds an ecological revetment for rivers and lakes.