Recycling waste to new resources

We are facing an urgent need to rapidly turn an old, linear economy with dwindling natural resources and depletion of important ecosystems into a modern, circular economy that includes production of new products from different waste flows. It is now time to minimise our waste and make the most of it as a resource with commercial value and the potential to bring new benefits for society.

ESCALATING USE OF RESOURCES

Efficient ecosystems are an absolute must for welfare and quality of life. A rapidly growing population, higher standard of living and massive increase in consumption have led to a situation in which ecosystems are rapidly depleted and our climate is destabilised. The extraction and processing of materials, fuels and foods of various types has tripled since 1970; and use of resources dominates widely in high-income countries, which have a per capita footprint 13 times higher than that of low-income countries. All in all, extraction and refinement of various natural resources is estimated to cause 90 per cent of loss of biodiversity and half of climate change1).

Biofertiliser and bio-nutrients add important nutrients to the soil and are beneficial for organic farming. Photo: Kyle Mackie
WASTE – A RAW MATERIAL WITH COMMERCIAL VALUE

For a long time, waste was seen as a problem, a cost and something to burn or dispose of. These days will soon be behind us. Waste can be turned into new raw materials to use as a resource by developing sorting at source and recycling of materials. Sorted materials replace other production materials in this way, thereby helping to reduce the use of virgin raw materials. This also involves significant energy savings.

Food waste from households, catering and restaurants can be sorted and processed biologically in order to produce plant nutrients and biogas. Old clothing and other textile waste are an untapped resource for the fashion industry, which is in great need of more sustainable material choices. Nowadays, materials can be separated into recycled cotton or polyester that can be turned into new clothes with less of a carbon footprint. Similar examples can be seen in a number of waste flows in our society. Increased awareness of the value of waste in combination with innovation, product design and new technical breakthroughs mean that both the business community and the public sector are switching to circular material flows and business models, using waste as a commodity.

CIRCULAR MANAGEMENT OF ORGANIC WASTE

Sweden produces around a million tonnes of food waste every year. At least 75 per cent of this food waste has to be sorted and processed biologically by 2023, according to a new milestone defined by the government in the transition to a biocircular economy. We can take advantage of the energy and nutrient content of products by collecting organic waste from households, remains from slaughterhouses, fertiliser from farms, leftover food from restaurants and food that cannot be sold in shops. There are a number of ways to do this, but one of the most effective is to use anaerobic, biological digestion. Waste facilities then become something of a biocircular industry instead, where waste is refined to make valuable products such as biogas for sustainable transport, district heating for heating buildings, biofertiliser and fields and plant nutrients for crops of leafy greens for restaurants and schools.

BIOGAS – FUELING FOSSIL-FREE TRANSPORT

Biogas is a unique example of circular economy. Biogas production is an effective way of taking advantage of the organic waste generated by our communities and using the digestion process to convert it into renewable biogas, a fossil-free fuel for the transport sector. Biogas is an excellent substitute for natural gas as its production is circular and resource-efficient. Using biogas as a fuel instead of diesel and petrol also helps to significantly improve air quality and reduce impact on health and the environment in cities thanks to a reduction in both nitrogen oxides (NOx) and harmful particulates. Emissions of sulphur oxides (SOx) leading to acidification of soil and water are almost eliminated with biogas, too. In Sweden, biogas use amounts to almost 4 TWh each year, and interest in this renewable fuel is greater than ever in a number of sectors.

Biogas is recycled from food waste and used as a fuel for buses. Photo: Susanne Walström
BIOFERTILISER – BENEFICIAL FOR AGRICULTURE

Biofertiliser is an organic fertiliser used in agriculture, adding important nutrients such as nitrogen and phosphorus to the soil so that crops can grow and flourish. Biofertiliser is produced using a circular process and is a nutrient-rich byproduct of the recycling and digestion of organic waste to biogas. Around 2.5 million tonnes of digestates from Swedish biogas plants are used as fertiliser for agricultural purposes each year2). Biofertiliser is increasingly replacing mineral fertilisers where the nitrogen is produced by means of a very energy-intensive method, and the phosphorus is extracted by mining phosphate ore at a small number of reserves in Africa. Many people are of the opinion that these reserves may cease to exist within a generation.

Biofertiliser is an organic fertiliser used in agriculture.
BIONUTRIENTS – FOOD WASTE BECOMES NUTRIENTS FOR CROPS

Alongside biogas and biofertiliser, bionutrients are a liquid nutrient solution which is also produced by digesting waste food and other organic waste. Bionutrients are very useful for hydroponic cultivation, i.e. indoor cultivation in water and without soil, solutions that are usually found in urban environments near to towns and cities. Thus plant nutrients are used to turn old food waste into new food, for example, by growing fresh herbs and leafy greens locally, in eco-friendly ways. Bionutrients can be used to great effect by both professional growers and hobbyists.

Peas Industries perceives a business opportunity in collecting society’s organic waste in efficient ways and meeting a growing need for both biogas and biofertiliser. This is done via our company Biond, which operates two waste plants in Sweden. These facilities operate as biocircular industries, with waste management as a service and biogas, biofertiliser and bionutrients as sustainable products.

Sources

1) European Academies’ Science Advisory Council (EASAC)

2) Swedish Energy Agency