Hydrated lime (calcium hydroxide) is used across a variety of industries due to its versatility. Here are the main industries where it plays a significant role:
- Construction Industry
- Mortar and Plaster: Used to improve workability, plasticity, and durability.
- Soil Stabilization: Hydrated lime is used to improve soil properties for construction foundations.
- Cement Production: Acts as a binding agent and additive in cement and concrete production.
- Water and Wastewater Treatment
- Water Purification: It is used to adjust pH and remove impurities like heavy metals from drinking water.
- Wastewater Treatment: Neutralizes acidic water and aids in precipitating harmful substances from industrial wastewater.
- Agriculture
- Soil Amendment: Used to neutralize acidic soils, promoting healthier crops and increasing soil fertility.
- Animal Feed: Acts as a calcium supplement in livestock feed.
- Chemical Industry
- Manufacturing Chemicals: Serves as a base material for producing various chemicals like calcium salts, calcium stearate, and calcium hypochlorite (bleaching powder).
- pH Regulation: Commonly used in chemical processes to maintain desired pH levels in reactions.
- Mining Industry
- Ore Processing: Hydrated lime is used to extract metals such as gold, silver, and copper through processes like flotation and cyanidation.
- Flue Gas Treatment: Helps remove sulfur dioxide (SO₂) and other acidic gases from flue emissions.
- Paper and Pulp Industry
- Pulp Production: Used in the causticizing process, which recovers sodium hydroxide (NaOH) from sodium carbonate in kraft pulp mills.
- Water Conditioning: Removes impurities from water used in papermaking processes.
- Food Industry
- Food Additive: Acts as a preservative and pH regulator in the production of pickles, tortillas (nixtamalization process), and other foods.
- Sugar Refining: Used to purify raw sugar by removing impurities in the production of refined sugar.
- Environmental Control
- Air Pollution Control: Reduces sulfur emissions in coal-fired power plants and other industrial facilities by capturing sulfur dioxide (SO₂) in flue gas desulfurization processes.
- Waste Management: Helps neutralize acidic waste and stabilize hazardous materials.
- Leather Industry
- Tanning Process: Used in the preparation and softening of hides before tanning by helping to remove hair and fats.
Hydrated lime’s strong alkaline properties and reactivity with water make it a critical component across various industries for treatment, processing, and stabilization purposes.