Study On Physical And Chemical Properties Of Hazardous Wastes And Compatibility In Cement Kilns

Due to the hazardous characteristics of hazardous wastes,it will endanger the safety of human health and the ecological environment seriously without proper disposal.At present,incineration and landfilling are two main ways to deal with hazardous waste in China,while there is still some shortcomings..With the rapid development of China's economy,industrialization and urbanization,the amount of hazardous waste will increase significantly,but its disposal capacity is far from enough,so it is urgent to find a new way to treat and disposal hazardous waste.Use of cement kilns to deal with hazardous wastes is a more popular approach.It mainly studied on the compatibility,physical and chemical properties of hazardous waste,collected from a company in Chongqing.High calorific value of hazardous waste is used as alternative fuel in cement production,while low calorific value of hazardous wastes used as alternative raw materials.The harmful components of hazardous waste,such as F,Cl,S,heavy metals have great influence in the quality of cement products,which should be under strict control.This paper tries to put forward a suitable quality control for cement plant internal management,and on this basis,burning compatibility model was established.Use oily sludge as an alternative raw material in cement production and it tested the XRD pattern,leaching toxicity,and compressive strength of calcined clinkers.It is shown that a high calorific value can make most of the hazardous waste a good combustion performance and suitable for burning in the cement kiln to take replace part of the fuel.Meanwhile,the good compatibility of hazerdous wastes can make them mixed as an alternative fuel.The proportion of alternative fuels reaches 6.9%,and the harmful components in the waste are within the national standard.Oliy sludge can reduce its moisture content by adding CaO or lime,and then used in cement kiln as an alternative within the ratio of 5%.The addition of raw materials will not affect the mineral phase and compressive strength of cement.Based on domestic and foreign studies and the national standard,the quality control values of F,Cl,S,Hg,Tl+Cd+Pb+15As are 0.25%,1%,2.5%,10 ppm,300ppm,respectively.