Science Inventory

DEVELOPMENT OF SOURCE-SEPARATION LATRINE TECHNOLOGY FOR SUSTAINABLE HUMAN WASTE MANAGEMENT IN RURAL GHANA

Impact/Purpose:

The current latrine facilities in the village Obodan (Ghana) are overused and cannot accommodate the entire community. To avoid the long waits, stench and unsanitary conditions of the public latrines, community members construct their own unlined pit latrines, posing a serious risk of groundwater contamination and local pollution. A preliminary trial of a source-separated latrine is being developed to alleviate the demands on existing infrastructure with a more sustainable model of human waste management. Past projects (KVIP installed by our team in 2005) in Obodan have not been sustainable due to maintenance costs coupled with a lack of accountability in fee collection. Private latrines will have more individual accountability and ownership, which along with community involvement should lead to sustainable project.

Description:

The biotransformation of the collected solid waste will be remotely monitored by measuring the accumulation of H2, CH4 and CO2 gases in the head-space of the collection chamber using an online gas analyzer. These gas levels will indicate the state of decomposition, which will be accelerated by periodic addition of sawdust, which should lower the organic carbon : nitrogen ratio to about 25:1 Thermocouples will also be installed to indicate elevated chamber temperatures typical of high decomposition rates. Operationally simple volume sensors based on solids levels will be employed to monitor the rate of waste accumulation to better size the future latrine chambers. To determine if the urine is suitable for reuse, the mineral content (N, P, K) will be analyzed on-site. The use of an online ammonia analyzer will be evaluated to provide long-term hands-free information. We will look to remove pathogens and cut down the usual six weeks of resonance time needed via a modular sand filtration unit. Measured pathogen indicator levels should be below the US standards of 200 fecal chloroform units / 100ml urine.

Record Details:

Record Type:PROJECT( ABSTRACT )
Start Date:08/15/2010
Completion Date:08/14/2011
Record ID: 249167