In recent years, the concept of a circular economy has emerged as a revolutionary solution to reduce waste and create value from it. Given the valuable biomass by-products that come from the sugar production process such as bagasse, tops and trash, the South African sugar sector has the potential to harness this circular economy approach for positive change and sustainable growth. It can achieve this by beneficiating its waste to generate a variety of products ranging from bioenergy, second-generation biofuels, animal feed and bioplastics.
Defining the Circular Economy
A circular economy can be defined as an economic system that ensures that maximum use is extracted from a resource and minimum waste is generated for disposal2.The traditional linear approach to the generation and disposal of waste where waste is disposed through burning, landfilling, incineration, burying and open pits has proved to be unstainable in the long run due to the negative impacts it poses on aquatic, terrestrial, and atmospheric ecosystems as well as human health1. The South African sugar could integrate the concept of the circular economy into its sugar production processes, contributing to not only environmental sustainability but also socio-economic sustainability by generating new business opportunities from the so-called “waste”.
The circular economy aims to redefine waste as a valuable resource. For the sugar industry, this would mean producing a variety of products from the straws, bagasse, ash from bagasse incineration, press mud, wastewater and molasses from the sugar production process3. This approach could utilize a large portion of the millions of tons of “waste” generated by the global sugarcane industry annually3.
The sugar cane value chain master plan has concluded but the work is unfinished
Some potential uses for these materials are highlighted below:
Bagasse
The fibrous residue left after sugarcane crushing is known as bagasse. The South African sugar industry already uses sugarcane bagasse as fuel in cogeneration plants to produce thermal energy and electricity to run the mills. Furthermore, it can be expanded to produce additional products such as biofuels, biodegradable packaging, or even fibreboard for construction3.
Molasses
The South African sugar industry produces some potable and industrial ethanol used to manufacture pharmaceutical intermediaries and products and alcoholic drinks4. Molasses could also be used to produce bioethanol for fuel blending, animal feed and cosmetics3.
Sugarcane Leaves and Tops (Straws)
Through green cane harvesting, these by-products can be left on the field as mulch. The mulch controls the weeds, conserves more water in the soil by reducing water evaporation and returns carbon and nutrients to the soil3. They can be collected manually or mechanically and like bagasse, be used for cogeneration or to produce second-generation bioethanol5.
Sustainability in Sugar Production:
The circular economy approach also extends to the agricultural aspects of sugar production. By implementing sustainable farming practices, such as precision agriculture, growers can reduce water usage, minimise chemical inputs, and enhance soil health. This not only improves environmental impact but also contributes to the long-term viability of sugar production. Achieving the transition to a circular sugar economy will, however, require collaboration among various stakeholders, including sugar producers, researchers, policymakers and public-private partnerships to drive the research and implementation of sustainable practices.
The sweet revolution of a circular sugar economy holds tremendous potential, benefiting both the industry and the planet. By reducing waste, optimizing resource usage, and diversifying revenue streams, the sector can decrease its environmental footprint, enhance competitiveness, and contribute to job creation in the green economy. Embracing sustainable practices and promoting the circular economy agenda on a larger scale will ensure a more sustainable future for the sugar industry.
