Diseño y puesta a punto de un reactor para el uso de la electrocoagulación como método de eliminación de fluoruros en agua de consumo humano

  1. Vicente Fernando Mena González
Supervised by:
  1. Ricardo Manuel Souto Suárez Director
  2. Juan José Santana Rodríguez Director

Defence university: Universidad de La Laguna

Year of defence: 2021

Type: Thesis

Teseo: 689558 DIALNET

Abstract

For years, the duality between the benefits and the toxicity of fluoride to public health has been clear. From this situation arises a concern about the composition of the water that is currently consumed and in particular its fluoride content, a problem observed for generations with the occurrence of many cases of dental fluorosis. According to various studies, most of the fluoride present in the waters comes from contact with soils of marine or volcanic origin. In particular, the waters coming from certain galleries in the north, northwest and south of Tenerife contain fluorides in concentrations that reach up to 12 mg/L. As much as the World Health Organization (WHO) recommends a maximum fluoride concentration of 1.5 mg/L, and this being the maximum limit allowed by the Spanish regulations on water for human consumption, there is a need to correct this parameter. For this reason, in order to make use of this groundwater of volcanic origin to supply the population, it is necessary to resort to mixing techniques with other waters with low fluoride content, or to use separation technologies capable of obtaining water suitable for human consumption (namely, electrodialysis [1,2], reverse osmosis [3,4], nanofiltration [5], activated alumina beds [6], chemical precipitation [7,8], etc.), although involving significant amounts of rejected water, which it can only be released into the marine environment. One of the little-proven technologies, which could be an economically interesting alternative for the elimination of fluorides from this water with almost total exploitation of the water flows, can be the use of electrochemical techniques for water treatment. In this context, electrochemical technologies attract growing technological interest by allowing greater ease and safety in their use, versatility and high environmental compatibility [1,6,9,10]. This is due to the fact that electrochemical technologies have the following advantages: (1) to operate at ambient temperature and pressure; (2) the operations in the systems are easy to perform; (3) the electrochemical system itself can be used for the in-situ production of chemical reagents, as well as for their disposal, avoiding the consequent risks of handling and eventual disposal after use; (4) modularity of electrochemical devices, which can be small enough to be transported to the place where their use is required; and (5) the high selectivity of electrochemical techniques that allows to act on particular reactions through the control of the electrical parameters of the system.