PROCESO DE TRATAMIENTO UTILIZADO PARA ELIMINAR ARSENICO EN UN POZO DE AGUA UBICADO EN ZIMAPÁN,

Abstract

The problem of arsenic contamination of wells located in the municipality of Zimapán, Hidalgo became evident in 1992. In August 2011 the construction began on the first floor area water treatment to remove arsenic from well water to treat the disabled since 1998 Muhi for exceeding the NOM-127-SSA1-1994. The well will provide 22 LPS will be treated by coagulation-flocculation process using FeCl3 as coagulant to reduce the concentration of arsenic in a higher concentration of 1 mg/L to 0.025 mg/L for the NOM. Chapter 1 provides background on the problems of pollution, characterization studies including groundwater well on Muhi, treatment processes for arsenic-contaminated water and sludge management. Chapter 2 presents the current normativities for maximum permissible levels of arsenic, national and international and Mexican Official Standards used for quantification of As Chapter 3 presents the methodology to be carried out and finally in Chapter 4, the capacity of the well and the technical evaluation of the treatment train. As a result it was found that the concentration of arsenic in the well the Muhi is greater than the maximum permissible limit set in changing of the NOM-127-SSA1-1994 which is 0.025 mg/L and that established by the World Health Organization which is 0.010 mg/L, so that the water isn’t for human consumption, the well will provide 22 LPS will be treated by coagulation-flocculation process. The removal efficiency of As will depend largely on the dose of coagulant FeCl3, and the dose of chlorine used to oxidize the arsenic in As+3 to As+5, with the coagulation-flocculation process, the crucial step in the train treatment. The sludge will be sent to landfill but can be a potential source of arsenic contamination when not meet the guidelines for disposal. As the coagulation-flocculation process, the determining step in the treatment train for arsenic removal is important to monitor the doses and amount of FeCl3.The agitation must be strong the first few minutes after adding coagulants and then slow stirring for optimum flocculation, the optimum pH should be between 6-8.To ensure in the taking domiciliary the concentration of 0.2-1.5 mg/L chlorine remaining established in the Mexican Official Norm suggested adding chlorine in the storage tank water and finally to verify the global quality of treated water is recommends periodically analyzed in an accredited laboratory.