The widespread adoption of biogas as a reliable alternative energy source seems like a nobrainer. Capturing energy rich methane produced from decaying materials is a proven technology yet its adoption as part of the renewable energy mix appears to have been overshadowed by wind and solar.
And by 2050, waste generation in Sub-Saharan Africa is expected to more than triple from current levels.
Plastics are especially problematic. If not collected and managed properly, they will contaminate and affect waterways and ecosystems for hundreds, if not thousands, of years. In 2016, the world generated 242 million tonnes of plastic waste, or 12 percent of all solid waste, according to the report.
What a Waste 2.0 stresses that solid waste management is critical for sustainable, healthy, and inclusive cities and communities, yet it is often overlooked, particularly in low-income countries. While more than one-third of waste in high-income countries is recovered through recycling and composting, only 4 percent of waste in low-income countries is recycled.
Researchers at the ARC-AE are going to great lengths to develop and promote crop cultivation and healthy soil properties using digestate. Any anaerobic digestion creates an end product called ‘digestate’, which will typically constitute 90-95% of the unconverted feedstock material. The anaerobic digestate makes an excellent renewable (green) fertiliser, with better characteristics than organic compost.
Integrated field experiments were recently conducted at various sites to ascertain digestate’s effects in comparison with chemical fertiliser on agricultural crops’ yield and profitability.
Crop yields were higher for plants grown with digestate compared to other fertiliser treatments. In addition, our analysis showed that the highest gross return was obtained from crops treated with biofertilisers. However, application of synthetic fertiliser in combination with biofertiliser can potentially increase crop yields and the subsequent economic return.
Our natural scientists, engineers and agricultural economists are working hard towards the establishment of protocols and mechanisms for end users. Some of the vital information an end user needs to know about are the following: storage, spreading strategy, application rate, properties of digestate and crop type, and time of application. – Dr Idan Chiyanzu, ARC-Agricultural Engineering