Utilization of cow-dung in brickmaking
Practical Action
Exchange rate at January 1999:
2.332 LS = 1 US $
End notes
1. A civil war is raging in the country since 1955 which only temporarily ceased between 1972 - 1983 (rule of
General Numeiri). Massive internal migration to urban and production centres, together with other
environmental and socio-economic factors have resulted in large uninhabited areas amongst Sudan's total
geographical area of 2,6 million square kilo meters.
2. The production and development of roofing tiles or sheets has ceased in the country with the departure of the
British rulers and Italian Missionaries. Houses in urban which are roofed with tiles reflect the value which is
attached to this material.
3. Practical Action, Sudan experimented with a vaulted kiln in eastern Sudan. A certain potter in Omdurman is
firing the same kiln with agricultural wastes and old tyres. Two Hoffmann kilns are operated in
Khartoum/Atbara.
4. Kassala soil is mainly of gurera type and results shown in Table (3) refer to this type of soil.
5. NEA: National Energy Administration, Khartoum.
6. gagad: seeds of a local tree used in dyeing hides and for treatment if coughs and diarrhoea.
7. Dung is ignited to warm cattle camps and ward off wild animals and insects. Unlike wood, it turns slowly and
camp fires can be left unattended. Its ashes are used for cleaning teeth and body decoration. Mixed with cow
urine and clay, dried and fired, dung produces brilliant red hair dyes. Potters fire their products using dung. It is
also used as a fertilizer by tobacco growers, and as a table salt by fishermen.
8. In green bricks, water is met in three ways: free water which fills the pores; water which clings to the pore walls
after free water is removed; and chemically combined water. The first two "water types" are removed during
drying and the third during firing.
TO < 150OC drying or smoking stage: last traces of free water are removed:
TO up to 800 OC preheating stage: clay is decomposed and its combined water is liberated and passing out
of the chimney;
(iii) TO > 800OC to max: full firing stage;
(iv) Soaking: maintain max. temperature: principal re-crystalization, recombination and liquid formation
(vitrification) reaction take place during this period.
9. Bricks are fired in clamps in batches of 80 - 500 thousands. Clamps of larger capacities are preferable because
they are more fuel-efficient than smaller ones (smaller surface areas).
10. Strength = kg/cm2; Water Absorption = %; Density = kg/cm2 x 103, Note: Values are averages of four individual
bricks for each dung composition.
11. Warped bricks with broken corners and large surface voids as a result of excessive water, characteristic of
slopmoulding.
This document was written by Mr. Mohammed Majzoub of Practical Action Sudan
in 1999 and was originally published by GTZ for The building advisory service and
information network (basin).
Mr. Mohammed Majzoub
Practical Action Sudan
PO Box 4172
Khartoum Central
Sudan
Tel: 00 249 183 460 419, 00 249 183 578 821 or 00 249 183 578 827
Fax: 00 249 183 472002 | Telex: 984 22190 ACROP SD
E-mail: sudan@practicalaction.org.sd
Practical Action
The Schumacher Centre
Bourton-on-Dunsmore
Rugby, Warwickshire, CV23 9QZ
United Kingdom
Tel: +44 (0)1926 634400
Fax: +44 (0)1926 634401
E-mail: inforserv@practicalaction.org.uk
Website: http://practicalaction.org/practicalanswers/
Practical Action is a development charity with a difference. We know the simplest ideas can have the
most profound, life-changing effect on poor people across the world. For over 40 years, we have been
working closely with some of the world’s poorest people - using simple technology to fight poverty and
transform their lives for the better. We currently work in 15 countries in Africa, South Asia and Latin
7 America.