$$\textbf{Concept:}$$ A neutralization reaction is when an acid and a base react to form water and salt and involves the combination of H+ ions and OH- ions to generate water.
$$\bullet$$ Acidic substances are present in industrial wastes. If these are directly disposed into the water, then they may be harmful to fishes, aquatic plants, and other aquatic animals. Therefore, basic substances are mixed in this waste to neutralize them.