A study of recycling resources on the processes of cement

• Main Authors: Nian-Fu Wang, 王年福
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/36596049227543156483

碩士 === 國立中央大學 === 土木工程學系碩士在職專班 === 91 === This study is based on the physical and chemical properties of recycling resources(industrial byproducts or wastes), taking legal restrictions into account, and the characteristics of three main producing processes of the cement (raw meal proportion, clinker sintering, cement grinding). It researches the possibility of different types of recycling waste materials in different producing processes. The chemical analysis and physical tests of the final products also make sure of its influential degree(s). In applying recycled resources, the legalities of rule restrictions and procedure don’t mean the inevitability of being applied; therefore, before proceeding to recycle the resources in cement industry, it’s necessary to proceed to considerable interior evaluations to make sure of its influences on producing procedures and final products. The research on applying recycled resources to three main producing processes of the cement shows the application of paper industrial sludge in raw meal proportion producing process, on the condition of chlorine included only 420 ppm and the total chlorine of raw meal limited to 130 ppm, is completely practicable. In applying petroleum coke to clinker sintering producing process, when the dosage comes to 20.05%, it shows disadvantage on the stable operation of the rotary kiln. The observation of microscope of clinker and the result of compressive strength of cement also shows the disadvantage when the dosage amounts to 12.69%; therefore, the application of petroleum coke should be limited under 12.69%. Applying anhydrite to cement grinding producing process shows it is not absolutely sure to have an influence on its compressive strength when the dosage comes to 30%. However, as far as the setting time and false set are concerned, the initial setting time can be shortened 27% when the dosage reaches 20%. Besides, the phenomenon of false set of paste is getting worse. It suggests the mixed proportion should be controlled under 15 %. In addition, the results of TCLP of the clinker or cement after applying in respective producing process conform the legal restrictions and it can be inferred that cement can be regarded as a superior matrix of solidification or stabilization. According to the research, cement industry can properly utilize the characteristics and predominance of producing process in recycling resources. It can also be expected that cement industry will play a “triplicate” role in the cycle among “ecology, life, and production” to maintain production, improve ecology and be related to daily life. Moreover, at first, only choose the application which has a minor influence on producing process and products, accumulate and expand experiences, and promote legal rules or restrictions, and we can make efforts to produce “Eco-Cement” and achieve the final purpose of taking large care of recycled resources and producing the least pollution.