Over the past years of experience, Lime Industries have collected numerous questions from customers and lime users and compiled them in our FAQ page.

Q: What is Calcination?

A: CALCINATION - Calcination is where limestone or limesand is burnt in a kiln. The raw material temperature is elevated to beyond 825C causing it to decompose. The resultant of the thermal decomposition is Quicklime with Carbon Dioxide released as a by-product.

CaCO3 + Heat ↔CaO + CO2
100g        56g    44g

Q: What is Hydrated Lime?

A: HYDRATED LIME – Is a derivative of Quicklime, the result of the hydration reaction between Quicklime and Water. The reaction also generates heat. The amount of water added will determine the whether the hydrated lime is a powder or a liquid. Hydrated Lime is available as a powder or a liquid.

CaO + H20 = Ca(OH)2 + heat

Q: What is the difference between Slaked Lime and Hydrated Lime?

A: Slaked lime and hydrated lime are often confused. Technically the addition of water to form a hydrated lime in powder form is called hydration. When the addition of water produces hydrated lime in a liquid form this process is called slaking.

Q: Is Agricultural Lime the same as Lime?

A:  The term agricultural lime, or "Ag-lime," usually refers to limestone. Limestone (calcium carbonate) is not the same as hydrated lime (calcium hydroxide).

 

Listed below are different names that are associated with lime in its different forms. These are not necessarily always accurate however in most cases the forms can be classified as follows:


Limestone- Often the criteria associated with these products are the particle size and the purity of the limestone.
Limestone is also known as: Limestone Road base, Ag-lime, Crushed limestone, Calcium Carbonate, CaCO3

Quicklime- Often the criteria associated with this product is the chemical purity, the quicklime reactivity and the particle size
Quicklime is also known as: Burnt lime, Active lime, Calcium Oxide, CaO 

Hydrated Lime (Powder) - Often the criteria associated with these products are the particle size and the purity of the hydrated lime. The purity can be expressed as a percentage of its Calcium Hydroxide component or by its Calcium Oxide (Quicklime) component.
Hydrated Lime Powder is also known as: Lime, Powdered lime, Hylime, Builders lime, Slaked Lime (See above), Calcium Hydroxide and Ca(OH)2

Hydrated Lime (Liquid) - Often the criteria associated with these products are the sloid content in the liquid or its chemical equivalent expressed as a percentage of its Calcium Hydroxide component or by its Calcium Oxide (Quicklime) component.
Hydrated Lime Liquid is also known as: Lime Putty, Lime Slurry, Milk of Lime, MOL, Calcium Hydroxide slurry, Calcium Hydroxide, Hydrated Lime slurry, Slaked lime and Liquid Lime.