Study On The Environment Characteristics Of Electrolytic Manganese Residue And Its Composite Cementitious Materials

Electrolytic manganese residue (EMR) is a kind of harmful solid waste of great amount and high moisture content,which comes from manganese industry when manganese carbonate ore is used to produce electrolytic manganese powder.The water-soluble manganese in EMR has greatly exceeded the limit,which caused serious contamination to the environment of the enterprise nearby.Meanwhile the total amount of sulphate takes up about 20% of EMR,so it is a very efficient means for the preparation of composite cementitious materials.However,because of the system's stability and manganese toxicity in itself,whether composite cementitious materials prepared by EMR is harmful to the environment is the focus of attention.Therefore,the study on the environmental characteristics of EMR and its composite cementitious materials is of great significance for the security of application and promotion of these new materials.First of all,this study in-full analyze environmental characteristics of EMR, focusing on the study of leaching toxicity on EMR.Then the curing effect of the water-soluble manganese in EMR cementitious material system such as EMR - Cement,EMR - Pretreating agent,EMR-Pretreating agent - Fly ash,EMR - Pretreating agent - Fly ash - Cement and leaching toxicity of manganese in system under various factors were studied.In the last,curing mechanism of manganese was analyzed by means of XRD and SEM .The results show that:â‘ The EMR is low-level radioactive waste,which is not corrosive,only the concentration of water-soluble divalent manganese is about 900 times of standard 2mg/L in"Integrated Wastewater Discharge Standard".â‘¡The pH value of the leaching agent is main factor affecting the leaching toxicity of EMR.Under acidic conditions (1