Neutralization of acidic water is used to reclaim mined land, while neutralization of soil promotes plant growth. Neutralization is also used for the safe disposal of acidic and basic hazardous wastes as well as to neutralize acids in the human body via antacid tablets and baking soda.
Water that runs off from mines becomes acidic, so it is neutralized with calcium oxide acting as the base to make it reusable. This procedure is effective but expensive, and other methods, such as using human-made wetlands containing water plants, are more cost-efficient neutralizing options for acid mine drainage.
Agricultural limestone-calcium carbonate or calcium sulfate neutralizes soil that becomes too acidic or basic by the natural acidic content of surrounding soil, too little rain or the effects of acid rain. This process is called liming, and it is used to encourage plant growth. Neutralization is also used to dispose of hazardous wastes that are too basic or acidic for regular disposal by applying chemicals, such as sodium bicarbonate and calcium carbonate, to produce non-hazardous salts that take up less space.
Antacid tablets neutralize gastric acid in the stomach that causes discomfort, and the use of sodium bicarbonate, also known as baking soda, neutralizes the alkaline environment in the digestive tract.