A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Solidification and stabilization of waste zeolite in cement matrix
Natural zeolites are often used to remove heavy metal ions from wastewaters. Their frequent use is due to the relatively low price of natural zeolites and to easy preparation of such material for removal of heavy metal ions. Zeolite tuff is ground to the desired size and alkali-activated if necessary, and is then ready for treatment of wastewater in the form of an active barrier. Once zeolite becomes saturated by heavy metal ions, it becomes a possible harmful waste itself, and should be taken care of in a manner that will not endanger the environment. A practical method of taking care of saturated zeolites is solidification and stabilization in cement matrix, where zeolite material is a substitute addition to cement. The cement composite obtained is tested by the US TCLP 'leaching test' for heavy metal ions in the elute. If the cement matrix containing a certain content of saturated zeolite passes the leaching test, its other properties are examined for its possible application as construction material. The effect of the substitute addition on hydration processes and possible pozzolan activity is examined, and on developed strength of the hydrated composite. A good indicator of the effect of the saturated zeolite added to cement is monitoring of the heat released, (Q), during the early hydration stage. The analysis of the Q-t curve obtained determines the effect of the addition to the kinetics of early hydration-retardation or acceleration of the process. By determining the total heat released in a specific hydration interval, one can derive conclusions on the progress of hydration and possible pozzolan activity of the addition. This study has examined the possibilities of solidification and stabilization of natural zeolite, clinoptilolite, saturated by Zn2+ ions, in type CEM I Portland cement. The decisive parameter for practical application of cement matrix containing saturated zeolite is strength developed during the first 28 days of hydration.
Solidification and stabilization of waste zeolite in cement matrix
Natural zeolites are often used to remove heavy metal ions from wastewaters. Their frequent use is due to the relatively low price of natural zeolites and to easy preparation of such material for removal of heavy metal ions. Zeolite tuff is ground to the desired size and alkali-activated if necessary, and is then ready for treatment of wastewater in the form of an active barrier. Once zeolite becomes saturated by heavy metal ions, it becomes a possible harmful waste itself, and should be taken care of in a manner that will not endanger the environment. A practical method of taking care of saturated zeolites is solidification and stabilization in cement matrix, where zeolite material is a substitute addition to cement. The cement composite obtained is tested by the US TCLP 'leaching test' for heavy metal ions in the elute. If the cement matrix containing a certain content of saturated zeolite passes the leaching test, its other properties are examined for its possible application as construction material. The effect of the substitute addition on hydration processes and possible pozzolan activity is examined, and on developed strength of the hydrated composite. A good indicator of the effect of the saturated zeolite added to cement is monitoring of the heat released, (Q), during the early hydration stage. The analysis of the Q-t curve obtained determines the effect of the addition to the kinetics of early hydration-retardation or acceleration of the process. By determining the total heat released in a specific hydration interval, one can derive conclusions on the progress of hydration and possible pozzolan activity of the addition. This study has examined the possibilities of solidification and stabilization of natural zeolite, clinoptilolite, saturated by Zn2+ ions, in type CEM I Portland cement. The decisive parameter for practical application of cement matrix containing saturated zeolite is strength developed during the first 28 days of hydration.
Solidification and stabilization of waste zeolite in cement matrix
Verfestigung und Stabilisierung von Zeolithabfällen in Zementmatrix
Dabic, Pero (author) / Krolo, Petar (author) / Bubic, Ana (author) / Krstulovic, Ruza (author)
2006
7 Seiten, 6 Bilder, 2 Tabellen, 7 Quellen
Conference paper
English
Stabilization/solidification systems in hydraulic matrix of electrodeposit waste
| British Library Online Contents | 1998
Microstructural Study of Cement Composites Produced by Hazardous Waste Stabilization/Solidification
| British Library Conference Proceedings | 2012
Solidification-Stabilization of a Tannery Waste with Blended Cement and Wyoming Bentonite
| Online Contents | 2000
Solidification/stabilization of Cr(VI) with cement
| British Library Online Contents | 2000