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close this bookThe Use of Effluents from Biolatrines in Tanzania (ADF, 1996, 38 pages)
View the document(introduction...)
View the documentForeword
Open this folder and view contentsIntroduction
Open this folder and view contentsThe problem defined
Open this folder and view contentsBiolatrine technology
View the documentPublic health aspects
View the documentFertilizer production and usage
View the documentResearch plan
Open this folder and view contentsResearch findings and interpretation
View the documentConclusions and recommendations
View the documentBibliography
View the documentAppendix


The African Development Foundation (ADF) Research Report Series presents the findings of studies undertaken as part of the Foundation's research grant program. The program is designed to support "action" research geared toward improving the overall quality, efficiency, and sustainability of self-reliant development. Research is carried out in concert with grassroots communities to understand and document the issues with which they are confronted. ADF expects researchers to explore problems directly related to grassroots development and to make concrete recommendations that will be useful to project designers and implementors, donor organizations, and government officials.

ADF's researchers are African scholars and development specialists, living and working on the Continent. The Foundation provides four different categories of research grants.

Gray Senior Fellowships - named in honor of former Congressman William H. Gray, III are awarded to academicians and development professionals who have demonstrated their commitment to grassroots development through careers in research, teaching, or public administration.

Bâ Applied Research Grants are provided to development professionals, scientists, and technicians who wish to study issues of direct significance to self-reliant development.

Leland Development Grants are awarded to scholars who will study topics that have direct bearing on improving the quality of projects that ADF and other donors support on behalf of the rural and urban poor.

Finally, the Foundation gives Knowledge Transfer Grants to support the provision of training to, or the production of training materials for or by, grassroots communities. At the time this grant was approved, the Foundation also granted Doctoral Fellowships to African students completing their dissertations.

Dr. Albert Butare, an engineer at Tanzania's Center for agricultural Mechanization and Rural Technology (CAMARTEC), has worked on developing inexpensive biogas digesters for rural areas. Biogas technology treats animal in a standard digester, and human waste in a biolatrine, by breaking down the organic matter in an anaerobic environment, killing pathogens and organisms which may be present, and forming a liquid slurry. The bacteria which break down and ferment the organic matter, when adequately balanced, will produce methane gas. The gas can be used for cooking and lighting. The slurry from standard biogas digesters is used to fertilize crops, but the slurry from biolatrines has not. He was awarded a Bâ Applied Research Grant in 1992 to analyze the effluent from biolatrine installations and to overcome societal resistance to using slurry as fertilizer.

In Dr. Butare's work, Analysis of the Effluent from Biolatrines in Tanzania, he states that effluent from the biolatrine is not used as fertilizer because of beliefs that the slurry is unsafe, as well as cultural restrictions. To overcome these restrictions, Dr. Butare sampled the effluent from several biolatrines for pathogens. He also conducted tests on soil and crops that had been treated with different types of fertilizer-animal manure, chemical fertilizers, and human slurry-to determine whether the use of slurry from the biolatrine produced harmful variations not present with animal manure or chemical fertilizers.

In all cases, Dr. Butare found that slurry from biolatrines is an effective fertilizer which does not expose the consumer to any of the risks assumed to be associated with human slurry. Additionally, demonstrations in the rural areas, where this technology would be most used, began to counter some of the taboos surrounding the use of human waste as a fertilizer. The Tanzanian government is already committed to the use of biogas as an energy source. An increasing number of households and institutions will be equipped with biolatrines and biogas digesters, resulting in readily available slurry for many rural Tanzanians. The costs are minimal and the slurry can be used to supplement or even replace more expensive chemical fertilizers, resulting in higher agricultural yields without increased costs.