Experimental Study On Solidification/Stabilization Of Polluted Sediment Of Pudong River In Fuzhou

The rapid development of China’s industry has led to urban river pollution,and pollutants are deposited in the river sediments,making the river sediments become black and smelly,affecting people’s daily lives seriously.In this paper,a series of physical,chemical and mechanical tests were carried out on the contaminated sediment of Pudong River in Jinan District of Fuzhou City.To study the formulation and effect of solidification and stabilization of contaminated sediment.The main research contents and conclusions of the thesis are as follows:(1)The basic physical,chemical and mechanical properties of the Pudong River pollution sediments in Fuzhou City were tested,and the basic physical,chemical and mechanical parameters of the contaminated sediment were obtained.The contents of heavy metals,organic matter,TN and TP in the polluted sediment were determined,and the environmental impact of contaminated sediments were evaluated.The test results showed that the content of heavy metals,TN and TP in the contaminated sediment exceeded the standard,indicating the necessity and urgency of river pollution sediment control.(2)Conducting research on soil physical-chemical-strength properties of contaminated sediments,under different curing agents(type,dosage,ratio),initial moisture content of sediment,maintenance age conditions,analyzing density,moisture content,pH,and strength of solidified soil.Setting up the relationship between the basic physical-chemical properties(density,water content,pH)and strength of the solidified soil.(3)The formation mechanism of the solidification strength of contaminated sediment was studied.The morphology and pore distribution of the products formed in the solidified soil were observed by scanning electron microscopy(SEM).The mineral component in the solidified soil is analyzed by X-ray diffraction test(XRD)too.It was found that the reaction product played the role of skeleton and filling in the solidified soil and enhanced solidified soil.The relationship between the relative peak intensity of the solidified soil mineral component and the strength of the solidified soil is established.(4)To carry out the study on the chemical stability of soil treated with contaminated sediment.The different curing agents(type,dosage,ratio),initial moisture content,and maintenance age are analyzed.The toxic leaching traits of the contaminated sediment after solidification were evaluated,and the chemical stability of the cured soil was evaluated.