Discipline: Technology and Engineering
Jaylen Scott - Southern University
Co-Author(s): Skyler Franklin, Southern University, Baton Rouge, LA
In certain areas of the world, water obtained from boreholes have high fluoride levels due to geological rock formations. For example in the Bongo District, located in the upper east region of Ghana, the main water source is derived from boreholes containing an excess amount of fluoride, 4 ppm above the World Health Organization (WHO) recommended intake for Fluoride in drinking water, that is 1.5 ppm. An adequate supply of fluoride levels is necessary to develop healthy bones and prevent tooth decay; however, excessive level of fluoride has detrimental effect on one’s health. Dental fluorosis is an extremely common disorder, characterized by hypo mineralization of tooth enamel caused by ingestion of excessive fluoride during enamel formation. Another manifestation of excessive fluoride is skeletal fluorosis, a bone disease caused by excessive accumulation of fluoride in the bones. Since there is no cure to fluorosis, the only remedy of the problem is prevention by extensive research to find a sustainable and cost effect way to eliminate excessive fluoride from water. In previous studies, a composite of abundant local soil (laterite) activated with alumina has been found to increase fluoride uptake and thereby improving the defluoridation performance to a level at or below the WHO recommended benchmark. This study seeks to investigate the defluoridation performance of Laterite composite with bio-sand. Two configurations of the composite laterite and bio-sand filtration system are tested. The design consists of the laterite composite column with a bio-sand filter that contained 10 kg of laterite to 2 kg of Alumina, and 10 kg of laterite to 1 kg of Alum. The Alum or Aluminum Sulfate (Al2(SO4)3 x 12H20) column was prepared by mixing the laterite with the liquid state of Alum. The Alum was treated with Sodium Hydroxide (NAOH) and washed until the Sodium Chloride was completely dissolved. Then the Alum was treated with Barium Chloride until it did not precipitate anymore and it got to a certain pH value (between 5.0 and 6.0). The Alum was chemically coated by hydrolysis. The Column adsorption tests were conducted by passing fluoride sparked water samples at fluoride concentration of 5.02mg/L and 6.4mg/L. The second column with Alum proved to be the most efficient in fluoride absorption. During the fluoride absorption test, the results show that PH levels levitate closer to a normal standard. which proves the pilot system to be effective. SEM micrographs of the physically coated alumina and the two chemically coated alumina laterite composite show a mixture of elements including Fe, Si, Ti and Al, which are closely associated. The EDX spectrum of the composite confirmed higher aluminum content than the raw laterite. Overall, the performance of the column with chemically coated alum was much better than that of the physically coated. Future work will be study effect of composite particulate size on fluoride adsorption rate and water volume flow rate.J Scott ERN abstract.pdf
Funder Acknowledgement(s): We thank the Kwame Nkrumah University of Science and Technology's Materials Science laboratory for hosting us during our stay in Kumasi, Ghana. Thank you to Dr. Francis Momade and Albert Adjaottor for their guidance throughout this research experience. Funding for this project was provided by the National Science Foundation under NSF-SUIRES (Grant # IIA 1358204) project.
Faculty Advisor: Patrick Mensah, firstname.lastname@example.org
Role: Design, Building water purification column and conducting experiments