Peat is a natural raw material that arises in bogs. Because of its special composition, this type of humus is often used to improve the structure of soils. However, this requires moorland areas to be drained, which has devastating consequences for the ecosystem. Now researchers have developed a new technology to produce artificial peat. It works like a pressure cooker recipe and delivers peat substitute within minutes. This makes artificial peat a sustainable alternative to natural peat, which takes thousands of years to form.
There is little oxygen in wet bogs. Organic material such as dead plants is only incompletely decomposed by microbes under these conditions. Over the course of thousands of years, peat is created. This natural humus precursor has acidic and moisture-binding properties, as well as a fibrous and porous structure, useful for soils. Peat is therefore used worldwide for agriculture and horticulture. However, in order to extract peat, bogs have to be drained, which has a negative impact on these complex ecosystems.
Peat substitute from the pressure cooker
A team led by Nader Marzban from the Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB) in Potsdam has now found a way to obtain the valuable substance in another way. The researchers developed two processes to produce artificial peat. “We can produce artificial peat from almost any organic raw material, including biomass such as wood, grasses, leaves and paludiculture plants such as reeds and sphagnum moss. This process requires water, pressure and temperatures between 70 and 120 degrees Celsius as well as a suitable recipe for successful production,” explains Marzban the basic principle of the process.
The inventors compare their first approach to cooking these ingredients in a pressure cooker at around 120 degrees Celsius. Under these conditions, a type of black humus precursor with the same properties as natural peat is created from low-fiber raw materials in just 30 minutes. The quick-cooking process quickly imitates the natural formation of peat, which would otherwise take thousands of years, as the team reports.
Marzban and his colleagues further developed this first process so that the individual “pots” never stand still, but rather simmer peat-like substrate continuously. Raw materials with a higher fiber content can also be used. In this two-stage process, the biomass is first cooked under pressure at around 70 degrees Celsius. The fibers are then mechanically crushed, triggering chemical reactions that release heat and form peat-like humus structures.
Contribution to the circular economy
In both peat replacement production processes, large amounts of carbon are bound through the processing of organic waste material and hardly any emissions are produced. The bottom line is that the process is climate positive. The technology could soon contribute to a sustainable, bio-based circular economy. “Artificial peat offers an opportunity to replace natural peat, reduce emissions and recycle biomass,” says Marzban. “The production of artificial peat could soon reach industrial production due to its scalability and low cost. However, the concept is just the beginning, an exciting starting point for continuous development, adaptation and innovation.”
Source: Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB)