Research is under way on new technology that aims to convert algae and any other biomass waste, such as bagasse, into organic fertiliser mats, or agrimats, Agricultural Research Council (ARC) senior researcher Dr Khumbulani Dhavu tells Engineering News.

The agrimats are manufactured by pressing this biomaterial in either a hot or cold press machine. These mats are intended for use as mulching material in agriculture, which aims to replace traditional plastic-based mulch mats with purely organic material that has potential to release nutrients into the soil.

Two press machines have been installed at the ARC’s Institute for Agricultural Engineering campus in Silverton, Pretoria. An expert from Tokyo University of Agriculture and Technology (TUAC) assisted with the installation and demonstration of the equipment before leaving the operation in South African hands in June.

The collaborative research project, which began in May 2017, is led locally by the Durban University of Technology, in partnership with the ARC, and in conjunction with Japanese partners Nagoya University and the TUAC.

The research is funded by the Department of Science and Innovation, in collaboration with the Japan Science and Technology Agency and the Japan International Cooperation Agency.

Under this project, oil will be extracted from algae harvested from water treatment plants at eThekwini municipality. After extracting this oil for biofuel purposes, the dry microalgal residue is then mixed with waste biomass from a variety of agriculture industrial processes – such as bagasse from sugar production, wood chips from timber production or any other crop residues – to produce material for agrimat production.

“We are currently familiarising our engineers and researchers on the operation of the machines where we are trying several proportional input variations. The agrimats are being subjected to various tests for the assessment of physical and chemical properties. This small-scale case study will help us determine the rate of degradation and how well the nutrients are released into the soil,” Dhavu explains.

The field test is being conducted at the ARC Ornamental and Vegetable campus in Roodeplaat, Pretoria.

Depending on the success of the research, the ARC aims to commercialise the agrimat technology in the near future, in conjunction with its local and international partners, Dhavu confirms.

To ensure that this technology takes root in South Africa, the research team is working on establishing a sustainable environmental business model, as well as training local personnel.