Lime production: traditional techniques in Patarra, Costa Rica
Practical Action
• The amount of waste produced by the lumber industry in the area is expected to
decline in the next five years, making lime burning increasingly dependent on timber.
• Working conditions for employees in the whole process are poor.
• The tendency to leave quicklime exposed to air for a period before hydrating it results
in some undesirable premature slaking.
• The system does attempt to separate out the 4 to 8% silicate-based impurities in the
lime which come from using an impure limestone.
The overall result of these problems is that the quality of the product is low in terms of both
the available lime content and the fineness. It is suitable only for agricultural purposes, and
only a low percentage is used in the construction industry, which, in any case is decreasing
its use of lime in the area. Marketing studies have shown that construction and other
industrial activities could increase their consumption of lime if the quality standards
improved without excessive increase in cost. The largest difficulty in obtaining a standard
quality for the lime is inadequate hydration.
Information at a glance
Type of kiln
Capital costs
Mode of production
Running costs
Type and quality of limestone
Fuel efficiency
Conversion rate CaCO3 TO CaO
Hydration
Sieving/classification
Milling
Quality of lime produced
Principal market
Number of persons employed (including
quarrying)
Traditional cylinder, open topped
Very low
One batch per 8 days, average of 15
batches per year
Low
Marble approx 80% CaCO3
16%
96%
Manual
Manual
Electric hammer mill
Low (average 45% available lime)
Agriculture
3 full time and 8 casuals
References and further reading
• Lime - An Introduction Practical Action Technical Brief
• Hydraulic Lime - An Introduction Practical Action Technical Brief
• Methods for testing lime in the field Practical Action Technical Brief
• How to calculate the Energy Efficiency of Lime Burning Practical Action Technical
Brief
• How to Build a Small Vertical Shaft Lime Kiln Practical Action Technical Brief
• A Small Lime Kiln for Batch and Continuous Firing Practical Action Technical Brief
• Pozzolanas: Lime-pozzolana Cements Practical Action Technical Brief
• Pozzolanas - An Introduction Practical Action Technical Brief
• Testing methods for pozzolanas Practical Action Technical Brief
• Pozzolanas: Portland-pozzolana Blended Cements Practical Action Technical Brief
• Pozzolanas - Calcined Clays & Shales, and Volcanic Ash Practical Action Technical
Brief
• Pozzolanas - Rice Husk Ash and Pulverised Fuel Ash Practical Action Technical Brief
• Small Scale Production of Lime for Building John Spiropoulos, GTZ,1985
• Gypsum Plaster: Its Manufacture and Use, A. Coburn, E. Dudley and R.Spence,
Practical Action Publishing, 1989 (now out of print).
• Supplementary Cementing Materials for Use in Blended Cements, R.J. Detwiler, J.I.
Bhatty, S. Bhattacharja, Research and Development Bulletin RD112T, Portland
Cement Association, Skokie, Illinois, USA, 1996
• Small-scale Lime-burning: A practical introduction M. Wingate and others, Practical
Action Publishing, 1985.
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