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The Differences Among Quicklime, Hydrated Lime and Limestone2023-08-01 11:02:20

About Lime

Lime is an inorganic cementing material that hardens through exposure to air, with calcium oxide as its primary component. It is produced by calcining materials high in calcium carbonate content, such as limestone, dolomite, chalk, and shells at temperatures ranging from 900-1100℃. As the earliest known cementing material used by humans, lime has been widely utilized in civil engineering applications and can also be employed for medicinal purposes.

Lime Classification


The chemical formula of lime is CaO, also known as calcium oxide, which is commonly utilized in construction sites. It is a naturally occurring rock primarily composed of calcined calcium carbonate, resulting in the removal of carbon dioxide gas and the formation of calcium oxide. This white substance possesses an amorphous structure and exhibits hygroscopic properties or can transform into hydrated lime upon contact with water. Additionally, it can be incorporated into lime slurry, plaster, and mortar for coating materials alongside its application as a building material. Quicklime finds extensive usage in various everyday products such as rubber, plastic, paper, toothpaste, cosmetics fillers, desiccants and disinfectants. In agriculture, it serves as a fertilizer by enhancing soil structure and supplementing plants with essential calcium.
Hydrated Lime
Hydrated lime, also known as calcium hydroxide or slaked lime, is a white powdery solid with the chemical formula Ca(OH)2. Upon addition of water, it separates into two distinct layers - the clear upper layer of lime water can be utilized for carbon dioxide testing purposes while the turbid lower layer of liquid is referred to as lime milk or lime slurry and commonly employed in construction applications. Calcium hydroxide dissolves readily in water and possesses strong alkaline properties that may cause skin and fabric corrosion. It finds diverse industrial uses and serves as both a fungicide and chemical raw material.
The primary constituent of limestone is calcium carbonate (CaCO3). Lime and limestone are extensively utilized as construction materials and industrial raw materials. Limestone can be directly processed into stone or calcined to produce quicklime. Quicklime, which absorbs moisture to form hydrated lime, constitutes the major component of Ca(OH)2, also known as calcium hydroxide. Hydrated lime can be employed as a coating material and brick adhesive in various forms such as lime paste and stone plaster.

The Difference Between Quicklime and Hydrated Lime

  1. The difference in ingredients: Quicklime is primarily composed of calcium oxide (CaO), while hydrated lime is mainly composed of calcium hydroxide (Ca(OH)2). Quicklime is produced by heating limestone at high temperatures in a lime kiln and has strong water absorption properties, which explains why it's often used as a desiccant in various products' packaging. When quicklime comes into contact with water, it generates significant heat and forms calcium hydroxide.
  1. The difference in usage: Quicklime, hydrated lime, and complex alkalis all have pink or white appearances and can be used as alkaline agents for wastewater treatment to enhance the alkalinity of the wastewater and coagulate phosphorus for removal. However, according to Shenlong Calcium Industry - a company that has been producing and selling calcium hydroxide for many years - quicklime is more commonly used in construction due to its physical property of absorbing and releasing heat; this property may cause pipes or equipment used in wastewater treatment to overheat or burn when quicklime is applied. Additionally, when quicklime comes into contact with soil during fertilization or rainwater exposure, it can also burn crops. On the other hand, hydrated lime finds more applications in fish pond disinfection and increasing soil pH value; however, using hydrated lime for fish pond disinfection may result in increased mud production.
  2. Different chemical formulas: Quicklime's chemical formula is CaO; whereas hydrated lime's chemical formula is Ca(OH)2.

The Relationship Between Quicklime,Hydrated lime and Limestone

Quicklime, also known as calcium oxide, can be dissolved in water to produce hydrated lime (CaO + H2O = Ca(OH)2).
Hydrated lime reacts with CO2 to form calcium carbonate (Ca(OH)2 + CO2 = CaCO3↓ + H2O).
The primary constituent of limestone is calcium carbonate, which is heated and calcined to obtain quicklime (CaCO3 =(high temperature)= CaO + CO2↑).
Therefore, these three substances are interconvertible; that is to say, quicklime and water yield hydrated lime, hydrated lime transforms into limestone through carbon dioxide reaction, and limestone decomposes into quicklime at high temperatures.

Introduce to Limestone Grinding Mill

 YGM Raymond Mill 
Capacity: 0.2-50 t/h
Feed Size:35 mm
Powder Fineness:50-325 mesh
The Raymond mill can operate autonomously without the need for additional auxiliary equipment. Throughout the production process, this equipment demonstrates exceptional reliability, low noise emission, consistent grain size distribution, and minimal energy consumption. The enhanced mill design allows for product adjustments suitable for small-scale production or challenging materials while ensuring high-quality steel processing in critical areas to guarantee safe and dependable operation.
HGM Ultrafine Grinding Mill
Capacity: 0.2-45 t/h
Feed Size: ≤20 mm
Powder Fineness: 325-3000 mesh
The ultrafine mill can process twice as much material as other mills while reducing energy consumption by 30% at the same finished particle size and with the same motor power. The rings and rollers are forged from special materials, resulting in a high utilization rate. Spare parts have a life cycle of about one year under the same grinding conditions and finishing size, which is 2-3 times longer than that of other grinding lengths. However, spare parts' life cycles may differ due to varying hardness levels of different materials. Problems caused by bolt loss or rapid wear of bearings and sealing components do not occur since there are no rolling bearings or screws in the grinding chamber. The final fineness of ground material can be adjusted between 325 mesh to 3000 mesh. Dust pollution and noise are significantly reduced by applying pulse bag dust collectors and silencers while ensuring even material entry into the machine, stable fineness adjustment during operation, increasing capacity efficiency, and reducing power consumption.

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