Reverse osmosis pilot plant employed for pollutants-free drinking water production from the groundwater Mezquital valley, Mexico: An alternative to solve water scarcity in Metropolitan area

As populations grow and industries expand, pollution of our water sources increases. These sources are vital for human consumption. The growing presence of diverse contaminants requires the installation of more complex drinking water treatment systems. The current research examines the technical and economic viability of purifying water extracted from underground aquifers in the Mezquital Valley and Actopan, both in Hidalgo, Mexico. The objective is to mitigate the water shortage affecting the Metropolitan area of the Valley of Mexico. In this work, two reverse osmosis (RO) pilot plants—one producing 1 liter per second and the other 5 liters per second—were used to purify water from three deep underground wells. A thorough water-quality analysis was performed, covering over 350 water characteristics. Three prefiltration systems were assessed: sand filters, zeolite filters, and microfiltration (a membrane process that removes small particles). The results showed that using reverse osmosis with membranes designed to block most salts enables compliance with the maximum permissible water limits for human consumption established by Mexican regulations and World Health Organization (WHO) guidelines. Complete removal (100%) was achieved for total dissolved solids (TDS), total hardness (a measure of calcium and magnesium content), and sulfanilamide (an antibiotic contaminant). For nitrates, sodium, and sulfamethoxazole (another antibiotic), removal rates were 94%, 87%, and 95%, respectively, when purifying water from MZ-303 well with a pilot plant flow rate of 5 liters per second.