16 research outputs found

    Constraints to domestic roofwater harvesting uptake in Uganda: an assessment

    Get PDF
    The constraints that affect the immediate take-up of roofwater harvesting in Uganda were; the limited availability of roofing of suitable type and adequate area per capita, the ‘excessive’ cost of RWH components and systems in Uganda and the absence of a supply chain for providing RWH systems for those who want them. The rural roofing constraint is severe and must be either accepted biasing the technology somewhat away from the poorest households or attacked via trials of rival ways of bypassing this constraint. Means of achieving reductions in costs include training, the promotion of the very concept of technology choice, experimentation with rival models for delivering RWH and the use of public/NGO purchasing to encourage more efficient forms of production

    Potential of Densification of Mango Waste and Effect of Binders on Produced Briquettes

    Get PDF
    In Uganda, agro-processing of fruits produces large volumes of agricultural wastes much of which are not utilized but disposed in the landfill. This study explored the possibility of producing biomass briquettes from mango waste (seed covers) that could be used for energy supply in small factories and for domestic cooking. Dried mango seed covers were crushed to particles of size 2 mm and bonded with three different binders; starch, starch-clay soil, and starch-red soil. The best mixing ratios for briquettes were; 4:1 (seed-cover: starch), 9:2:1 (seed cover: starch: clay soil), and 16:4:1 (seed-cover: starch: red soil). The formed briquettes were subjected to several standard methods to verify their suitability as fuels. The briquette properties tested were moisture content, volatile matter, ash content, fixed carbon content, calorific value, compressive strength, and gaseous emissions. Results showed that briquettes bonded with only starch had a significantly (p ≤ 0.05) higher fuel properties with low: moisture content (11.9%), volatile matter (16.0%), ash content (2.8%) and emissions (0.178% CO, 0.0021% (CH)X , 1.14% CO2 and no NOx); higher fixed carbon (69.3%), breaking strength (maximum force, 34 N and compressive stress, 273 N/mm2) and calorific values (16,140 KJ/Kg)  compared to starch-red soil and starch-clay soil briquettes.  But after a linear regression analysis, results further showed that maximum force (R2 = 0.636) and ash content (R2 = 0.520) were good indicators of energy content of a particular briquette. However, more research is needed on using other binder types rather than cassava starch which is considered as food

    Assessment of the suitability of pineapple waste as feedstock for vermicomposting

    Get PDF
    Declining soil fertility is a challenge to sustainable agricultural production in sub-Saharan Africa with a case of Uganda. However, the large volumes of agricultural waste generated from pineapples can be converted into soil conditioners through vermicomposting. by the use of earthworms. Several types of agricultural waste have been studied extensively as vermicompost feedstock, but little work exists on pineapple waste. The objective of this study was to investigate the suitability of pineapple waste for vermicomposting. To achieve this, an assessment of the physicochemical properties of fresh, pre-composted pineapple waste, and the resultant vermicompost, and determination of the optimal feeding rate and stocking density were performed.  The study revealed that pre-composting reduced the moisture content (28.8%), VOC (10.3%), and increased the pH (56.8%) which was helpful in waste stabilization as well as in the mass reduction of the waste. Vermicomposting after pre- composting increased the bulk density (92.3%), ash content (25.4%), pH (10%), EC (14.3%), total phosphorus (20.9%) and total potassium (28.4%) but decreased the moisture content (29.1%), VOC (11.8%), organic carbon (81.4%), total nitrogen (21.3%) and the C:N ratio (76.4%) of the pineapple waste hence giving a more stabilized and mineralized vermicompost. The study further revealed an optimal feeding rate of 2 kg feeds/kg worms and a stocking density of 1 kg worms/m2 for complete nitrogen mineralization of the pineapple waste and 1 kg feeds/kg worms and 0.5 kg worms/m2 for higher phosphorus concentrations. The degradation of the pineapple waste by earthworms demonstrated the practicability of vermicomposting as a simple and low-cost technology of converting pineapple waste into an effective nutrient rich soil amendment.

    Transforming Corn Stover to Useful Transport Fuel Blends in Resource-Limited Settings

    Get PDF
    Development of local technologies is crucial to the sustainable energy agenda in resource-limited countries and the world. Strengthening local green technologies and promoting local utilization will reduce carbon emissions that could be generated during transportation and delivery of green products from one country to another. In this paper we developed bio-oil/diesel blends using a low-tech pyrolysis system designed for smallholder farmers in developing countries and tested their appropriateness for diesel engines using standard ASTM methods. Corn stover retrieved from smallholder farmers in Gayaza, Uganda were pyrolyzed in a batch rocket stove reactor at 350 °C and liquid bio-oil harvested. Bio-oil chemical composition was analyzed by Gas Chromatography equipped with Flame Ionization Detector (GC-FID). Bio-oil/diesel emulsions in ternary concentrations 5%, 10% and 20% bio-oil weight were developed with 1% concentration of sorbitan monolaurate as an emulsifier. The bio-oil/diesel emulsions and distillates had property ranges: specific gravities at 15 °C 827.4–830.7 kg m−3, specific gravities at 20 °C 823.9–827.2 kg m−3, kinematic viscosities at 40 °C 3.01–3.22 mm2/s, initial boiling points 140–160 °C, final boiling points 354–368 °C, and calculated cetane indexes 56.80–57.63. These properties of the bio-oil/diesel blends and their distillates compare well with standard transportation diesel fuel. The emulsion distillates meet the standard requirements for automotive diesel in East Africa

    Rainwater harvesting knowledge and practice for agricultural production in a changing climate: A review from Uganda’s perspective

    Get PDF
    With a changing climate in Uganda, rainfall distribution patterns have become more irregular over time and space. Excess water during rainy season is causing runoff, soil erosion, nutrient depletion and crop damage which reduce the productive capacity of land, while on the other hand, prolonged droughts during the crop growing period have become common occurrences. Additionally, pastoralists lose livestock during the dry period each year in the Cattle Corridor of Uganda due to water shortage and lack of forage. It thus remains difficult to achieve the agricultural development targets identified in the National Development Plan for Uganda, without addressing regular incidences of adverse impacts of climate change. Currently there are no well explained approaches which can contribute to adoption of technologies like rainwater management systems which are crucial in enhancing crop yields and livestock production during periods of water shortage. The overarching objective of this paper was to carry out an assessment of the status, performance, and scope for improving rainwater harvesting (RWH) for small-scale agriculture under local conditions. Accordingly, research gaps in RWH technologies were identified and documented to inform future studies. The research was carried out in the semi-arid areas of Nakasongola, Rakai, and Hoima Districts characterized by crop-livestock dependent livelihoods. Findings show that RWH Technologies can enable smallholder farmers and agro-pastoralists to become more resilient to increasing climate variability and climate change by conserving soil and water thus increasing food production and enhancing food security. Small-scale irrigation systems have enabled farmers adapt to drought challenges by enhancing crop yields and allowing farmers to target for higher market prices usually associated with the effects of drought. However, there are challenges including threats to sustainability of such established systems because of lack of community participation in systems’ monitoring and maintenances, and vandalism, and some systems require high investment costs.

    A critical analysis of physiochemical properties influencing pit latrine emptying and feacal sludge disposal in Kampala Slums, Uganda

    Get PDF
    Inadequate information on physiochemical properties of faecal sludge leads to inappropriate design of pit emptying devices and poor faecal sludge disposal contributing to environmental pollution. This study undertook a critical analysis of physiochemical properties of feacal sludge that influence design and performance of pit emptying devices and faecal sludge disposal for improved faecal sludge management in urban slums. The physiochemical properties determined were; Moisture content (MC), ash content (AC), total solids (TS), volatile solids (VS), nitrogen (N), phosphorous (P), potassium (K) and pH. Samples were collected from 55 unlined pits at depths of 0, 0.5, 1 and 1.5 m from pit surface. The unlined pits in this study were purposively selected from slums in Kampala. A sample of 300 g was sucked from each depth using a manual sampling tool and emptied into a plastic container. The container was then wrapped in a black plastic bag and transported in cooler boxes to the lab for analysis. The properties were subjected to Principal Component Analysis to isolate the critical parameters that affect pit emptying and faecal sludge disposal. The mean results were: MC of 86 ± 8.37%; TS of 0.14 ± 0.08 g/g wet sample; VS of 0.73 ± 0.32 g/g dry sample; pH of 8.0 ± 1.5; AC of 0.35± 0.18 g/g dry sample; TN of 3.5 ± 0.08%; K of 2.2± 0.13% and P of 1.4± 0.05%. It was concluded that physiochemical properties in Ugandan pits are comparable to those of global pits except for the acidic conditions at top surface in some pits, and higher moisture content in pits due to the high water table. PCA results showed that moisture content and total solids affected pit emptying techniques while fractional content of N, P and pH affect most choice of faecal sludge disposal technique.Key words: Pit latrine, faecal sludge management, developing countries, physiochemical properties, pit emptying

    Improving Maize Shelling Operation Using Motorized Mobile Shellers: <em>A Step towards Reducing Postharvest Losses in Low Developing Countries</em>

    Get PDF
    Maize shelling is still a challenge in low developing countries with more efforts required to advance this operation. In Uganda, motorized immobile maize shellers have been fabricated locally to enhance the shelling operation. However, their performance has not elated the farmers. The unsatisfactory performance is a result of these shellers being fabricated by local artisan with finite understanding of the maize grain characteristics and operation factors to optimize maize shelling. In addition, farmers in these countries have a deficiency of power to operate the motorized maize shellers available. Transportation of these motorized maize shellers is also still a challenge and it imposes an extra cost to the farmers hence reducing their profits from maize growing. In this chapter, we reviewed maize shelling process in low developing countries particularly the categories of maize shelling, maize sheller design requirements, use of equations to design sheller parts, modification of the motorized maize shellers and case studies on the mobile maize shellers, comparing them with immobile maize shellers. The study concluded that on addition to other sheller performance attributes, motorized mobile maize shellers can solve transportation challenges associated with motorized immobile maize shellers

    Mapping the medical outcomes study HIV health survey (MOS-HIV) to the EuroQoL 5 Dimension (EQ-5D-3L) utility index

    Get PDF
    10.1186/s12955-019-1135-8Health and Quality of Life Outcomes1718

    Evaluation of FAO AquaCrop Model for Simulating Rainfed Maize Growth and Yields in Uganda

    No full text
    Uganda&#8217;s agriculture is mainly rainfed. While farmers make efforts to increase food output to respond to the demands of a fast growing population, they are vulnerable to losses attributed to fluctuating weather patterns due to the global climate change. Therefore, it is necessary to explore ways of improving production in rainfed agricultural systems to save farmers labour and input costs in situations where the grain harvest would be zero due to crop failure. In this study, the Food and Agriculture Organization (FAO) AquaCrop model was evaluated for its predictability potential of maize growth and yields. The study was conducted at Makerere University Agricultural Research Institute Kabanyolo (MUARIK) in Uganda for three seasons. Maize growth and yield data was collected during the following seasons: Season 1, September to December 2014; Season 2, March to July 2015; and Season 3, September to December 2015. The model was calibrated using season 1 canopy cover data. The relative errors of simulated canopy cover ranged from &#8722;0.3% to &#8722;13.58% for different stages of the crop growth. The deviation of the simulated final biomass from measured data for the three seasons ranged from &#8722;15.4% to 11.6%, while the deviation of the final yield ranged from &#8722;2.8 to 2.0. These results suggest that FAO AquaCrop can be used in the prediction of rainfed agricultural outputs, and hence, has greater potential to guide management practices towards increasing food production

    Performance evaluation and optimization of the maize shelling operation of the multi-purpose farm vehicle

    Get PDF
    Small-scale farmers register high postharvest losses partly due to failure to carry out primary processing operations. Most of the maize shellers on the Ugandan market lead to high percentage of broken maize grains thus raising the risk of aflatoxin infection during storage. In this study, the operation of an existing maize sheller on the market with a shelling speed of 870 rpm for maize at 13 % moisture content was tested. The main objective of this study therefore was twofold; (i) to develop and evaluate a maize sheller and (ii) to optimize the multi-purpose vehicle shelling operation. The improved maize sheller was designed, fabricated, evaluated and optimized using a factorial experiment with shelling speed and moisture content as the main effects at three levels. Analysis of Variance was done using R-studio. A cost-benefit analysis of the shelling technology was conducted. The obtained results showed that a reduction in moisture content and an increase in shelling speed increased the shelling efficiency, the grain damage percentage, output capacity and the cleaning efficiency. The optimum moisture content and the shelling speed of the multi-purpose vehicle maize shelling were 13% and 896 rpm respectively. Except the shelling efficiency, the results of the modified maize sheller were significantly different (p&lt;0.05) from those of the market sheller. The payback period was 1.37 years while the benefit-cost ratio was 1.07. The optimized maize shelling operation of the multi-purpose vehicle is therefore economically viable
    corecore