Complete Lime Production and Whitewash: From Limestone to Plaster
⟁ cover painted for this edition — the source module carried no illustrations
Complete Lime Production and Whitewash: From Limestone to Plaster
Lime is one of the most versatile materials in human history. This campaign covers lime burning, slaking, mortar making, whitewash, and agricultural applications.
Chapter 1: Limestone and Lime Types
Material
Chemical Formula
Source
Use
Limestone (raw)
CaCO3
Quarried or collected
Raw material
Quicklime (burned)
CaO
Limestone heated to 1,650°F+
Mortar, plaster, agriculture
Slaked lime (hydrated)
Ca(OH)2
Quicklime + water
Mortar, whitewash, soil amendment
Lime putty
Ca(OH)2 + water
Slaked lime aged in water
Premium mortar, fine plaster
Hydraulic lime
Ca(OH)2 + silicates
Impure limestone burned
Sets underwater, stronger mortar
Chapter 2: Lime Burning
Kiln Type
Capacity
Fuel
Temperature
Time
Difficulty
Pit kiln (clamp)
100-500 lbs
Wood
1,650-2,000°F
24-72 hours
Low-moderate
Flare kiln
500-2,000 lbs
Wood
1,650-2,000°F
24-48 hours
Moderate
Draw kiln (continuous)
Continuous
Wood, coal
1,650-2,000°F
Continuous
High
Pit kiln method: 1) Dig pit 3-4 feet deep, 4-6 feet diameter. 2) Line bottom with fire grate (stones or metal bars). 3) Stack limestone pieces above grate (fist-sized, loosely stacked). 4) Leave air channels between stones. 5) Build fire below grate. 6) Maintain fire for 24-72 hours (temperature must exceed 1,650°F). 7) Limestone changes from gray to white as it burns. 8) Burned lime is lighter in weight (lost CO2). 9) Test: burned lime crumbles easily and reacts vigorously with water. 10) Let cool completely before handling. 11) Store quicklime in airtight container (absorbs moisture from air). 12) Caution: quicklime is caustic; wear eye protection and gloves.
Chapter 3: Slaking
Slaking process: 1) Place quicklime in metal or stone container (not plastic). 2) Add water slowly (quicklime reacts violently with water). 3) Reaction produces intense heat (can boil water). 4) Steam and spattering are dangerous (wear full protection). 5) Add water until lime is fully hydrated (thick paste). 6) Stir thoroughly. 7) Result: lime putty (calcium hydroxide paste). 8) For dry hydrated lime: add less water, let dry to powder. 9) Lime putty improves with age (store under water for weeks to months). 10) Aged lime putty makes the finest plaster and mortar.
Slaking Method
Water Ratio
Result
Use
Dry slaking
Minimum water
Dry powder (hydrated lime)
Mortar, agriculture
Wet slaking
Excess water
Lime putty (paste)
Fine plaster, whitewash
Hot slaking
Moderate water
Hot paste
Immediate mortar use
Chapter 4: Applications
Application
Recipe
Use
Properties
Lime mortar
1 lime putty : 3 sand
Masonry joints
Flexible, breathable, self-healing
Lime plaster
1 lime putty : 2-3 sand
Wall coating
Breathable, antimicrobial
Whitewash
Lime putty + water (thin)
Paint/coating
Antimicrobial, reflective, cheap
Limewash
Hydrated lime + water
Exterior paint
Weather-resistant, traditional
Soil amendment
Hydrated lime or ag lime
Raise soil pH
Corrects acidic soil
Water treatment
Hydrated lime
Purify water
Raises pH, precipitates contaminants
Tanning
Hydrated lime + water
Remove hair from hides
Alkaline bath loosens hair
Nixtamalization
Hydrated lime + water
Process corn
Releases niacin, improves nutrition
Whitewash recipe: 1) Mix hydrated lime with water to milk-like consistency. 2) Optional: add salt (1 cup per gallon) for durability. 3) Optional: add flour paste (1/2 cup per gallon) for adhesion. 4) Apply with brush to clean, damp surface. 5) Apply thin coats (thick coats crack and peel). 6) Multiple thin coats build up coverage. 7) Whitewash is antimicrobial (lime kills bacteria and mold). 8) Reapply annually for best appearance.
Chapter 5: Safety
Hazard
Source
Protection
First Aid
Chemical burns
Quicklime, slaking
Gloves, goggles, long sleeves
Flush with water 15+ minutes
Eye damage
Lime dust, splashing
Safety goggles (sealed)
Flush with water, seek medical help
Heat burns
Slaking reaction
Stand back, add water slowly
Cool burn, seek medical help
Respiratory
Lime dust
Dust mask or respirator
Move to fresh air
Skin irritation
Wet lime (mortar, plaster)
Gloves, barrier cream
Wash thoroughly
Reference Card
Limestone plus heat equals quicklime (heating limestone above 1,650°F drives off carbon dioxide, leaving calcium oxide; this is the fundamental reaction of lime production). 2. Quicklime plus water equals slaked lime (adding water to quicklime produces a violent, exothermic reaction; the result is calcium hydroxide, which is the working form of lime). 3. Slaking is dangerous (the reaction with water produces extreme heat and spattering; always add water to lime slowly, wearing full protective equipment). 4. Lime putty improves with age (aged lime putty makes smoother, stronger plaster and mortar; store under water for months if possible). 5. Whitewash is antimicrobial (lime-based whitewash kills bacteria and mold on contact; this is why barns, dairies, and hospitals were traditionally whitewashed). 6. Lime mortar breathes (unlike cement mortar, lime mortar allows moisture to pass through; this prevents trapped moisture from damaging stone and brick). 7. Lime corrects acidic soil (agricultural lime raises soil pH, making nutrients available to plants; test soil pH before applying). 8. Lime is one of humanity's oldest materials (lime plaster, mortar, and whitewash have been used for over 10,000 years; it remains one of the most useful materials you can produce).
