Preparation of acidic buffer solution, useful for improving water quality, comprises setting a primary carbon dioxide subsaturation in water body and adding carbon dioxide-generating feedstock and alkaline raw materials e.g. calcium oxide

摘要

Preparation of an acidic buffer solution in surface water, preferably in acidic and mineralized open-pit mining lakes, comprises: setting a primary carbon dioxide subsaturation in the water body by adding alkaline feedstock; subsequently adding carbon dioxide and/or carbon dioxide-generating feedstock; and adding the alkaline raw materials e.g. calcium oxide until the calcite saturation index for the water body is reduced to a value = -5, the carbon dioxide partial pressure is reduced with respect to the initial value and the pH is set at a value = 6. Preparation of an acidic buffer solution in surface water, preferably in acidic and mineralized open-pit mining lakes, by the use of alkaline raw materials such as calcium oxide, magnesium oxide, sodium hydroxide, calcium dihydroxide in the presence of carbon dioxide, comprises: setting a primary carbon dioxide subsaturation in the water body at a partial pressure of less than 0.00035 atm by adding alkaline feedstock, as a result of which the calcite saturation index for the water body increases to = -5 and the pH increases from 8 to 12; simultaneously or subsequently adding carbon dioxide and/or carbon dioxide-generating feedstock, as a result of which the carbon dioxide partial pressure is raised to = 0.00035 atm and the calcite saturation index for the water body is decreased to = 0 and the pH value is reduced to 5-8 or adjusting a primary carbon dioxide supersaturation in the water body by the addition of an appropriate quantity of carbon dioxide and/or carbon dioxide-generating feedstock, as a result of which the carbon dioxide partial pressure is raised to a value of = 0.00035 atm and the calcite saturation index for the water body is reduced to a value = 0 and the pH value is reduced to a value of less than 8; and adding the alkaline raw materials until the calcite saturation index for the water body is reduced to a value = -5, the carbon dioxide partial pressure is reduced with respect to the initial value and the pH is set at a value = 6.