Bone char quality and defluoridation capacity in contact precipitation

J. Albertus, Henrik Bregnhøj, M. Kongpun

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearch


Samples from six different brands of bone char are tested for their capacity to remove fluoride from water in batch. Initial concentrations of 10 mg/L and contact times of 6 hours are used. The removal capacities observed are 0.6-1.1 mg/g on an average, s.d. being 0.16. Addition of calcium and phosphate compounds to the jar experiments results in more than doubling of these capacities, on average 1.9 mg/g, s.d. being 0.14. One of bone char products is setup in columns are fed with water, 100 mg/L, for saturation. Hereafter the coloumns are fed with water of 10 mgF/L where calcium and phosphate are added as in the contact precipitation process. The results show that the columns are able to remove up to 700 bedvolumes, before the concentration of fluoride in the effluent water breaks through, above 1.5 mg/L. Operational removal capacities observed are 7 and 9 mg/L, depending on contact time and the dosage of chemicals. It is discussed that longer contact time and higher dosage of calcium and phosphate may result in longer operation periods in the contact precipitation columns.
Original languageEnglish
Title of host publicationProceedings of the 3rd International Workshop on Fluorosis Prevention and Defluoridation of Water
EditorsE. Dahi, S. Rajchagool, N. Osiriphan
Place of PublicationChiang Mai, Thailand
PublisherISFR, EnDeCo & ICOH
Publication date2002
Publication statusPublished - 2002
Event3rd International Workshop on Fluorosis Prevention and Defluoridation of Water - Chiang Mai, Thailand
Duration: 20 Nov 200024 Nov 2000
Conference number: 3


Workshop3rd International Workshop on Fluorosis Prevention and Defluoridation of Water
CityChiang Mai


  • sorption
  • Bone char
  • contact precipitation
  • batch experiment
  • pyrolysis
  • defluoridation
  • dynamic removal capacity
  • calcination
  • flowexperiment
  • operational removal capacity
  • jar test

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