Page 75 - Industrial Plants

From organic waste to biomethane,

bringing carbon back to the soil

A success story of the circular economy in the UK

Bjorn Blankespoor, Head of International Sales, BTS

naerobic digestion (AD) is a natural passenger cars fueled with biomethane.
process where bacteria decompose AD prevents organic waste from rotting in landfills and
organic waste in the absence of emitting harmful methane into the atmosphere. Unlike
oxygen to produce biogas (a open-air landfills and even composting facilities, AD
renewable fuel) and digestate (an processes organic waste in a closed environment,
A organic soil fertilizer, amendment, or capturing and containing all emissions in the end-
additive). The process allows for recycling excess products of biogas and digestate and, preventing
organic waste, creating renewable energy, and those emissions from being released into the
returning nutrients and carbon back to the soil all have atmosphere.
significant impacts on reducing greenhouse gas (GHG) Digestate, an often-overlooked end product of AD, is
emissions, making AD a vital tool in reversing the an organic soil amendment that
effects of climate change. replaces synthetic fertilizers and sequesters carbon
back into the soil. Digestate improves the soil health of
Biogas produced through AD uses organic sources our farms and communities by recycling nutrients and
that consume carbon dioxide from the atmosphere carbon in organic waste back into the soil.
during photosynthesis, making it a truly renewable Reducing emissions from the energy, waste, and
fuel. When one considers the cumulative effects - agriculture sectors is crucial in our global fight against
diversion from landfills, the offsetting the use of fossil climate change. The protection of our biosphere and
fuels, and the recycling of nutrients and carbon back the advance innovative technologies go hand-in-hand.
to the soil - AD is a carbon-limiting technology that the result is the creation of a circular economy
can reduce atmospheric GHG concentrations. diverting organic waste from landfills, generating
environmentally friendly fuel, and producing an organic
“Biogas produced through AD uses soil amendment that offsets the use of synthetic
organic sources that consume fertilizers and locks atmospheric carbon in the ground.
carbon dioxide from the atmosphere
during photosynthesis, making it a AD facilities have three stages: feedstock receipt, the
truly renewable fuel digestion process, and end-product utilization (see
Figure 1).
Biogas can also be refined into renewable natural gas
(RNG), which is fully interchangeable with conventional, The resulting products of digesting feedstocks in an
fossil fuel-based natural gas and has the potential to AD facility is biogas and digestate. Methane is the
displace over 40% of conventional natural gas usage primary constituents of biogas, which can be refined
in transportation. Fueling vehicles with RNG could into renewable natural gas (RNG) by removing its non-
prevent 5 tons of GHG emissions annually, per each methane components.

IndustrIal Plants - September 2021
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