Although Quicklime & Hydrated Lime are both made from ground limestone (calcium carbonate), they are obviously not identical products. Here, we explore some of the differences between the two, using one versus the other, and why you might choose one over the other.
The first and primary difference is found in the molecular structure. Quicklime is calcium oxide, and Hydrated Lime is calcium hydroxide.
The two products also look different. Quicklime will typically appear as a more dense, BB-like product, and may be dull-white or grayer in color. Hydrated Lime is a bright white, lighter, and more ‘fluffy’ product.
Quicklime also known as burnt lime or calcium oxide (CaO) is a versatile alkaline chemical compound with many uses across various industries. However, finding places to purchase quicklime can be challenging these days compared to the past. In this comprehensive guide, we’ll explore the best options for where to source quicklime along with how to use it effectively and safely.
What is Quicklime Used For?
Before discussing where to get it, let’s first understand the versatility of quicklime:
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Stabilizing soils – It’s added to clay soils to improve strength and workability through a process called lime stabilization.
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Mortar and plaster – Quicklime has traditionally been used to make lime mortar and plasters for brickwork and renders. It slowly reacts with air to gain strength over time.
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Waste treatment – It can be added during sewage sludge treatment to reduce odors and microbes.
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Steel production – Quicklime helps remove impurities like silica from iron ore during steel manufacturing.
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Flue gas treatment – It can capture sulfur dioxide from power plant flue gases.
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Leather tanning – Mixing quicklime with water makes calcium hydroxide or slaked lime used in leather processing.
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Sugar refining – Quicklime is added during juice purification to precipitate impurities.
As you can see, quicklime has many industrial and construction uses. Now let’s explore the best places to buy it.
Where to Buy Quicklime
Unfortunately, quicklime has become more difficult to source compared to the past. Here are some of the main options for where you can purchase it today:
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Online – Retailers like Amazon offer quicklime for sale online in smaller quantities, often around 50 lb bags. Expect to pay premium prices, sometimes upwards of $100 per bag.
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Farm supply or feed stores – Some agricultural retailers carry quicklime bags for soil stabilization applications, though selection is often limited.
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Masonry supply companies – Stores catering to masons may stock quicklime for historic mortar production, though availability varies regionally.
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Chemical supply companies – Industrial chemical suppliers are one of the few consistent sources for pure quicklime, though pricing is very high unless buying full pallet quantities.
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Direct from manufacturers – Larger regional lime producers may sell quicklime direct to consumers if you arrange local pickup. Check for kilns located near you.
Unless you need industrial bulk volumes, sourcing smaller bags can be difficult. Expect to pay higher prices or buy full pallets online for better value.
Using Quicklime Effectively and Safely
Once you secure a quicklime supply, proper handling is crucial for both results and safety:
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Wear protective gear like gloves, goggles, mask and coveralls when handling. The reaction with moisture can cause burns.
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Fully hydrate and slake quicklime before use by slowly and carefully adding water. This makes the slaked lime paste safer to work with.
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Only use stainless steel or plastic mixing tools. The chemical reaction corrodes most metals.
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Work in small batches, mixing only what you need. Leftover quicklime remains hazardous.
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Follow recommended application rates carefully to avoid using excess. More is rarely better with caustic chemicals.
While quicklime requires care to use properly, when handled safely it offers many unique benefits not easily achieved with other products. Be sure to take precautions and manage it responsibly.
Frequently Asked Questions
Here are answers to some common questions about purchasing and using quicklime:
Is quicklime the same as hydrated lime?
No, quicklime (calcium oxide) and hydrated lime (calcium hydroxide) are different chemicals.
Is agricultural lime the same as quicklime?
No, ag lime is usually ground limestone (calcium carbonate), not the purified quicklime compound.
Where can I buy small bags of quicklime?
Online retailers provide the most options for buying smaller quantities vs. industrial use. Try stores like Amazon or local masonry suppliers.
What’s the difference between quicklime and slaked lime?
Slaked lime is quicklime combined with water, making it hydrated calcium oxide, while quicklime remains non-hydrated until water is added.
How much water should be used per pound of quicklime?
Use approximately 0.4 gallons of water per 1 lb of quicklime. Always add powder to water slowly to prevent dangerous reactions.
Can I make my own quicklime by burning limestone?
It’s possible but very difficult, requiring heating limestone between 900–1000°C. It’s easier and safer to buy premade quicklime.
Conclusion
Production: Quick vs Hydrated
Limestone is a type of sedimentary rock. In its raw form, it is calcium carbonate. The first step in the production process for either product is the extraction of limestone from quarries and mines. Then, the limestone is crushed, screened, and washed. By heating this crushed limestone to a high temperature, carbon dioxide is released, and calcium oxide (Quicklime) is left. To make Hydrated Lime, the production process is taken a step further, and the product is then quenched with water. This is called “slaking”, and is done in a controlled way since it does produce an exothermic reaction (it gets hot!).