The waste fiuorgypsum was modified and applied as a cement retarder. The main chemical composition and mineral structure of the waste fluorgypsum were analyzed. Scanning electron microscopy （SEM） and eight-channel m...The waste fiuorgypsum was modified and applied as a cement retarder. The main chemical composition and mineral structure of the waste fluorgypsum were analyzed. Scanning electron microscopy （SEM） and eight-channel micro-calorimeter （TAM Air） were employed to analyze the changes in morphology and study the application performance of the modified fluorgypsum, respectively. Experimental results indicate that the flexural strength and compressive strength of the modified fiuorgypsurn are roughly equal to those of the natural gypsum. The morphology of the crystal of the fiuorgypsum changes from block particle into trimetric short column. The fluorgypsum crystals stagger mutually and improve the strength of the hardened body. The modified fluorgypsum as cement retarder could delay the hydration, reduce the heat of the hydration and make the setting time, volume stability, and the S03 content of the cement meet the national standards. The modified fluorgypsum is a good substitute for the natural gypsum.展开更多
The chemical composition and mineral structure of fluorgypsum as well as its harm to application in cement were elaborately analyzed. The primary fluorgypsum was modified and its applications in cement＇s production w...The chemical composition and mineral structure of fluorgypsum as well as its harm to application in cement were elaborately analyzed. The primary fluorgypsum was modified and its applications in cement＇s production were studied. The technological flow chart of preparing modified fluorgypsum was given. Experimental results indicate that hydration ratio the modified fluorgypsum through adding compound additive for 14d is about 70%. The modified fluorgypsum as cement retarder has certain stimulation to fly ash and increases the strength of compound cement. In addition, its adding amount is lower than that of natural gypsum. The modified fluorgypsum is a good substitute for natural gypsum.展开更多
The characteristics of the desulphurized gypsum produced in the flue gas desulphurization （FGD） process of the Baosteel sintering plant are investigated in this study. According to the technical and quality requirem...The characteristics of the desulphurized gypsum produced in the flue gas desulphurization （FGD） process of the Baosteel sintering plant are investigated in this study. According to the technical and quality requirements of gypsum in the cement industry ,the feasibility of using desulphurized gypsum as a cement retarder is also studied. The results show that desulphurized gypsum can be used as a cement retarder instead of natural gypsum.展开更多
基金Project(21003014) supported by the National Natural Science Foundation of ChinaProject(2010FJ3167) supported by the Hunan Provincial Science and Technology Program,ChinaProject(K1104029-11) supported by the Changsha IT Project
文摘The waste fiuorgypsum was modified and applied as a cement retarder. The main chemical composition and mineral structure of the waste fluorgypsum were analyzed. Scanning electron microscopy （SEM） and eight-channel micro-calorimeter （TAM Air） were employed to analyze the changes in morphology and study the application performance of the modified fluorgypsum, respectively. Experimental results indicate that the flexural strength and compressive strength of the modified fiuorgypsurn are roughly equal to those of the natural gypsum. The morphology of the crystal of the fiuorgypsum changes from block particle into trimetric short column. The fluorgypsum crystals stagger mutually and improve the strength of the hardened body. The modified fluorgypsum as cement retarder could delay the hydration, reduce the heat of the hydration and make the setting time, volume stability, and the S03 content of the cement meet the national standards. The modified fluorgypsum is a good substitute for the natural gypsum.
基金the National Natural Science Foundation of China(No.20471046)
文摘The chemical composition and mineral structure of fluorgypsum as well as its harm to application in cement were elaborately analyzed. The primary fluorgypsum was modified and its applications in cement＇s production were studied. The technological flow chart of preparing modified fluorgypsum was given. Experimental results indicate that hydration ratio the modified fluorgypsum through adding compound additive for 14d is about 70%. The modified fluorgypsum as cement retarder has certain stimulation to fly ash and increases the strength of compound cement. In addition, its adding amount is lower than that of natural gypsum. The modified fluorgypsum is a good substitute for natural gypsum.
文摘The characteristics of the desulphurized gypsum produced in the flue gas desulphurization （FGD） process of the Baosteel sintering plant are investigated in this study. According to the technical and quality requirements of gypsum in the cement industry ,the feasibility of using desulphurized gypsum as a cement retarder is also studied. The results show that desulphurized gypsum can be used as a cement retarder instead of natural gypsum.
