NEUTRALIZACIÓN DEL POTENCIAL DE HIDRÓGENO DEL AGUA MIEL DE UN BENEFICIO HÚMEDO TECNIFICADO DE CAFÉ UTILIZANDO HIDRÓXIDO DE CALCIO Y BICARBONATO DE SODIO

Abstract

Coffee waste water, have an average pH of 4.68 units, when this water is discharged into bodies of water change drastically the natural acidity and causing increased turbidity and reduced the dissolved oxygen. Prior to conducting treatment by biological way, it is necessary to perform the addition of alkalinity which can be through two alkalizing groups: those that react with carbon dioxide to form bicarbónica alkalinity as calcium hydroxide and that offer directly bicarbónica alkalinity as sodium bicarbonate. In laboratory, using fifteen differents samples of coffee waste water was added different concentration of sodium bicarbonate and calcium hydroxide. For each and every concentration of alkalizing, its pH was measured in each laboratory test and after 24 hours. With all pH values and by descriptive statistical analysis it was concluded that a concentration of 2.50 grams of sodium bicarbonate per liter of coffee waste water, neutralizes the pH in a mean value of 6.23 units, and additional buffer capacity as 24 hours later, the medium pH value for this concentration was 6.27 units. By contrast, using calcium hydroxide at a concentration of 2.50 grams per liter of coffee waste water as is traditionally done, pH increases abruptly up to 10.20 units and 8.75 units 24 hours later.