Study On Key Techniques For Reduction And Attenuation Of River Sediment

In this paper,the research on the reduction and attenuation of river sediments has been carried out to develop a new type of composite flocculant and G-type curing agent.After a series of tests,the treatment effects of the two reagents are very significant.The main conclusions are as follows:(1)Two or more flocculants are compounded for the nature of the sediment.Through the sedimentation column test,six suitable composite flocculants were obtained and the sediment test was carried out,including direct use of curing agent and curing agent after flocculation,and curing strength of cured samples 7d,14 d and28d.Evaluation,which proves that the curing effect is good;(2)After the flocculation of the sediment,the combined vacuum preloading is used for the dehydration test.By analyzing the dewatering effect of different flocculants in the flocculation-vacuum preloading test,the water quality,the dissipation of pore pressure,the shear strength of the cross plate,the compression coefficient and the consolidation coefficient,two sets of composites suitable for vacuum preloading were obtained.Type flocculant;(4)In the case of the combination of two flocculants,the incorporation of lime can increase the shear strength of the cross plate.And the addition of composite flocculant has effect on the particle size and gradation distribution of the soil.(5)The incorporation of composite flocculant in the test will improve the compressibility of the soil and increase the void ratio and consolidation coefficient of the soil,which is conducive to the consolidation and consolidation of the soil.(3)The phosphorus-removing microbial treatment method is applied to the heavy metals in the sediment to determine the optimum treatment conditions for the phosphorus microorganisms,and the characterization of the precipitates after the microbial treatment is analyzed,and the removal rate of the heavy metals is more than80%.(6)Heavy metal treatment has little effect on the water content before and after flocculation and before and after vacuum preloading,and does not affect the pore water pressure dissipation and the turbidity degree of drainage water quality.