A case study in lime production ~ Sri Lanka
Practical Action
The difficulties of obtaining fuelwood continue. The requirement of a permit to
transport wood of any kind has resulted in appreciable price increases including an
artificial scarcity of wood for lime burning.
Although lime producers claim that the calcining efficiency of their kilns are fairly
satisfactory (over 85% being converted to quicklime) observations reveal that
fuelwood used for burning is considerably in excess of what is required.
Due to inefficient slaking methods the quicklime is not fully hydrated. Because of a
high demand for the product the hydration stage is often rushed to get the product to
the market as quickly as possible and so is not allowed to run to completion.
There seems to be an attitude among lime users that availability is more important than
quality. Although the quality of lime produced from coral is usually fairly satisfactory, it in no
way approaches that required for the chemical and other industries. The bulk of the lime
produced by traditional lime producers is consumed by the building trade.
Information at a glance
Type of kiln
Capital costs
Mode of production
Running costs
Type and quality of limestone
Type and quantity of fuel
Fuel efficiency
Conversion rate CaCO3 TO CaO
Hydration
Sieving/classification
Quality of lime produced
Principal market
Number of persons employed (including
quarrying)
Traditional, vertical shaft, cylindrical
Very low
Akurala area – small batches of coral ¾ to 1
½ tons per batch
Hill country – continuous 1 ½ tons a day
quicklime
Very low
42% of available lime
Trunks of the cocoanut palm and other types
of wood about ½ ton per batch of 1 ton of
coral
Low
58%
Manual
Manual
42% of available lime
Mainly building construction
2 full-time, 3-4 casual at Akurala
Hill country (dolomite) – 2 full-time, 8-10
casual
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
Testing methods for pozzolanas Practical Action Technical Brief
Lime Kiln Designs: Small & Medium Scale Oil Fired Lime Kilns Practical Action
Technical Brief
A Small Lime Kiln for Batch and Continuous Firing Practical Action Technical Brief
The Small Scale Vertical Shaft Lime Kiln: A practical guide to design, construction and
operation, Kelvin Mason, Practical Action Publishing, ISBN 9781853394652
Small-scale Lime-burning: A practical introduction Michael Wingate, Practical Action
Publishing, ISBN 9780946688012
A Case Study in Lime Production No2 Improved Techniques at Chenkumbi, Malawi.
Practical Action Technical Brief
Lime and Alternative Binders in East Africa Elijah Agevi et al, Practical Action /ODA,
1995
Lime and Other Alternative Cements Neville Hill et al, Practical Action Publishing, 1992
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