URI | http://purl.tuc.gr/dl/dias/3FAEBE56-9AE6-4830-A528-25256B2B9761 | - |
Identifier | https://doi.org/10.1016/j.clay.2006.09.010 | - |
Language | en | - |
Extent | 10 pages | en |
Title | Gelation of water-bentonite suspensions at high temperatures and rheological control with lignite addition | en |
Creator | Christidis Georgios | en |
Creator | Χρηστιδης Γεωργιος | el |
Creator | Vassilios C. Kelessidis | en |
Creator | Pagona Makri | en |
Creator | Vassiliki Hadjistamou | en |
Creator | Christina Tsamantaki | en |
Creator | Athanasios Mihalakis | en |
Creator | Cassiani Papanicolaou | en |
Creator | Antonios Foscolos | en |
Publisher | Elsevier | en |
Content Summary | The effectiveness of lignite addition to prevent gelation of 6.42% w/w water–bentonite suspensions exposed to high
temperatures has been studied, using twenty six lignites from various basins in Greece with variable organic and inorganic contents
at concentrations of 0.5% and 3.0%. The lignite-free bentonite suspensions thickened considerably when heated at 177 °C for 16 h,
as was indicated by a two-fold increase of the yield stress, when compared to samples hydrated only at room temperature. However
plastic viscosity did not change appreciably. Full flow curves showed a Herschel–Bulkley behavior of all suspensions. Addition of
lignite maintained the stability of the suspensions exposed to high temperatures (177 °C) by keeping the yield stress low and did
not affect plastic viscosity. Some of the Greek lignites performed equally well with a commercial lignite product and improvements
of 80 to 100% of the stability of the suspensions, compared to lignite-free suspensions, have been found. Lignite addition also
lowered yield stresses for the hydrated samples. No specific trends have been identified between the effectiveness of lignites to
stabilize bentonite suspensions and their humic and fulvic acids and humins content. However, those lignites with highest humic
and fulvic acid contents have maximum stabilization capacity. Similarly, no specific trends have been observed between the
stabilization capacity of lignites and their inorganic components such as oxygen and ash content and also with the cation exchange
capacity. The effectiveness of the Greek lignites to stabilize bentonite suspensions is very high and the minor differences in the
efficiency of the different lignites cannot be attributed solely to any specific component | en |
Type of Item | Peer-Reviewed Journal Publication | en |
Type of Item | Δημοσίευση σε Περιοδικό με Κριτές | el |
License | http://creativecommons.org/licenses/by/4.0/ | en |
Date of Item | 2015-10-01 | - |
Date of Publication | 2007 | - |
Bibliographic Citation | V. C. Kelessidis , G. Christidis , P. Makri ,V.Hadjistamou , C. Tsamantaki , A. Mihalakis ,C.Papanicolaou, A. Foscolos ,"Gelation of water–bentonite suspensions at high temperatures and rheological control with lignite addition " ,Ap. Clay Sc.,vol. 36.no.4 ,pp.221-231 ,2007.doi :10.1016/j.clay.2006.09.010 | en |