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Production of biomass briquettes of good strength and combustion characteristics usually requires the addition of a binder material to the feedstock. This study was aimed at developing a methodology for producing briquettes from water hyacinth at low compression pressures without using a binder material. Fresh water hyacinth was chopped to a maximum length of 3 cm, sun-dried to a moisture content of about 10%, mixed with shredded waste office paper in four water hyacinth to paper proportions on weight basis (100:0, 90:10, 80:20 and 70:30). The mixtures were soaked in water for three days and briquetted using a 6-cylinder screw briquetting machine. The resulting briquettes were subjected to standard strength and combustion tests. A Completely Randomized Design with four treatments replicated five times was used as the experimental design. Results from the study indicate no significant differences in compressed density, relaxed density, relaxation ratio and calorific value between the briquettes. The results further indicate that briquettes made without a binder material have significantly low but adequate shatter resistance, low ignition time, high burning rate and take a longer time to bring water to boil. It can be concluded that good quality water hyacinth briquettes can be produced at low compression pressures without using a binder material. This methodology can potentially increase adoption of water hyacinth briquettes in areas with poor access to binder materials. The originality of the research is the development of a water hyacinth briquetting methodology that does not use binder materials. [ABSTRACT FROM AUTHOR]

Surface irrigation is associated with low irrigation efficiencies and exerts a lot of pressure on water resources. Despite this, the irrigation method remains dominant in Malawi and other sub-Saharan Africa countries. A need exists to improve surface irrigation efficiencies in the wake of water scarcity. Applications of surface irrigation simulation, evaluation and design (SIRMOD) software in improving surface irrigation performance have been reported worldwide. However, no documentation exists on SIRMOD application in Malawi. A study was therefore conducted to investigate how furrow irrigation system performance could be improved at Kasinthula Cane Growers Scheme in Malawi using SIRMOD software. Field data collected from the scheme were used to calibrate the model before simulating water advance and recession times. Statistical comparisons of the simulated advance and recession times with corresponding observed field data showed that the model closely simulated field conditions; hence, it was deemed suitable for the scheme. Results from SIRMOD optimization procedure indicated that application efficiencies could be improved by 32–63% through reductions in furrow lengths, water inflow sizes and inflow cutoff times. The study established the need for Malawi and other developing countries to develop policies on optimization of irrigation performance using computer models such as SIRMOD. [ABSTRACT FROM AUTHOR]

Malawi's dairy farming is dominated by smallholder farmers living in rural areas. The farmers practise hand-milking and have an unreliable supply of clean water. Consequently, low milk yields of generally low quality are realized. Machines can safely be used for milking cows if proper hygiene exists. Utilization of milking machines requires a steady supply of clean water, hence the need for water pumps. Milking machine and water pump operation require a steady energy supply, yet access to the national electricity grid is currently very low in rural areas. The current study assessed energy and water use among smallholder dairy farmers at Chitsanzo Milk Bulking Group in Dedza, Malawi. The study also assessed the farmers' knowledge and interest in use of solar-powered milking machines and groundwater pumps. Data were collected using structured questionnaires, focus group discussions and key informant interviews. The study shows that most farmers spent huge amounts of time fetching water due to long distances (0.08–2 km) to water sources; hence, approximately 90% of the respondents under-watered their dairy animals. All milking was done by hand, which is time consuming and increases the chance of milk contamination. A need to research the introduction of solar-powered milking machines and groundwater water pumping was established. [ABSTRACT FROM AUTHOR]

This study evaluated effects of integrated application of compost and secondary treated sewage effluent (STSE) on net N mineralization (NMnet) and ryegrass production. Soil incubation and pot (glasshouse) trials were carried out on two soil types, sandy loam and clay loam. NMnetwas significantly higher (p < 0.05) in clay loam than in sandy loam soil. Increasing contribution of compost in integrated compost and STSE resulted in N immobilization. Experimental data on ryegrass dry matter (DM) obtained in pot trial was consistent with NMnettrend observed in soil incubation. In pot trial, ryegrass DM yield and N use efficiency reduced with increasing contribution of N from compost. For every unit addition of compost (25%), DM yield of ryegrass declined by 573 and 462 kg DM−1in sandy loam and clay loam, respectively. [ABSTRACT FROM AUTHOR]