Study On The Technology Of Using The Sieved Landfill-stablized Waste As Base Material

The paper researches on sieved landfill-stablized waste in informal landfill of Beijing region,which is sieved into the soil of 5 particular size gradations(5mm,7mm,10mm,15mm and 20mm)through sieve,and added with smashing plant litter for improvement.16 kinds of plants containing arbor,shrub and herb three types such as lilac,sophora japonica,sobina vulgaris,amorpha fruticosa and arundo donax,etc.are chosen for planting experiment.This test determines the sieved landfill-stablized waste and compares the testing result with CJ-T 340-2001 National Standard of the People’s Republic of China for Urban Construction Industry-Planting Soil for Greening and GB 3838-2002 National Standard of the People’s Republic of China-Environmental Quality Standard for Surface Water.Through analysis,the heavy metals content of sieved landfill-stablized waste of 5 particular size gradation is up to the standard,proving that the experimental soil is free from heavy metal pollution;seen from indexes such as pH of soil,gross water soluble salt,organic matter content,water-holding capacity of field and non-capillary pores,content of each group is up to the standard.Seen from the test data of leachate index firstly collected,leachate is free from heavy metal pollution.Seen from indexes such as total nitrogen,chemical oxygen demand and five-day bod,etc.,only each index of the soil with particular size not more than 5mm can meet V-class environmental quality standard for surface water,while the chemical oxygen demand and five-day BOD of the soil of other particular sizes exceed standard in different extents.And then the plants of current growing season are tested for four plant growthform indexes such as height increment,ground diameter increment,new branch length and new branch diameter.Through the analysis on the data of four indexes,it is shown that the survival rate of plants is not obviously related to component and particular size of sieved landfill;deciduous tree(paper mulberry,acer mono,ailanthus altissima and sophora japonica,etc.)grows the least in landfill of 7mm-10mm particular size,while conifer(pinus tabuliformis,Sabina vulgaris and pinus bungeama)grows well in the landfill;dungarunga(zizyphus jujube,lilac)grows relatively well in the landfill of 10-15mm particular size;herbaceous plant(willow,branch millet and arundo donax)grows relatively well in the landfill with particular size less than 5mm and will grow lesser along with the increasing of particular size of sieved landfill;growing of platycladus orientalis,euonymus maackii,euonymus kiautschovicus and Huamulan of control group has no obvious difference from that of experimental group.Combining above soil and leachate indexes,it can be seen that the sieved landfill with particular size less than 5mm is relatively appropriate for being used as the basic materials for seedlings cultivation.Based on the above,we chose Sophora japonica Linn.,Ziziphus jujubaMill.var.spinosa(Bunge)Hu ex H.,Lndigofera kirilowii Maxim.ex Palib,Euonymus maackii Rupr.,Platycladus orientalis(L.)Franco,Panicum virgatum,Arundo donax as the most suitab.species.