A study looking into the effects of filtering wastewater into willow trees could help to create renewable biofuels, green chemicals and clean water, whilst at the same reducing a growing problem caused by contaminated water.
The project, published in Science of the Total Environment, suggests that over 30 million litres of wastewater per hectare of willow trees could be treated every year using this approach, which the research team described as a “biorefinery”.
-
Why Willow Trees?
Willow has historically been one of the most widely used woods for medicinal and even manufacturing purposes, with a fishing net made from willow dating back over 10,000 years.
It has considerable upside for biofuel production because it grows very quickly and its biomass can be transformed into a range of sustainable products, including bioethanol and green plastics produced without fossil fuels.
Willows are also exceptionally hardy trees that are very naturally tolerant of contamination, and it is this quality in particular that has made this research fascinating.
Willows do not, for example, need to be grown on high-quality land and so do not use land that could be used for food crops, and the powerful roots of willow trees naturally filter out the nitrogen that is commonly found in sewage waste.
This versatility is not unknown, and a previous study has suggested that a fifth of the world’s energy requirements could be provided through willow-produced biofuel without damaging food production whatsoever.
Willow also produces a range of highly useful chemicals, of which the most well-known and well-used is salicin, a precursor to aspirin.
Through filtering sewage, willow has also been found to produce a range of green chemicals with antimicrobial, antioxidant and anti-inflammatory properties.
Research has even been undertaken into ways to recover valuable metals using plant technologies that essentially extract them from contaminated soil.
-
Creating Biofuel From Willow Trees
Willow is a particularly effective producer of biomass, the plant material that is either burned or refined into biofuels such as bioethanol.
Once the willow has grown and been replanted, the wood from the trees is taken to a processing plant where through surface grinding it is turned into chippings.
These chippings could be burned on their own as for wood-burning stoves and boilers, but in most cases are taken to a biorefinery, where the clippings and chippings undergo a chemical process to convert them into bioethanol, typically through fermentation of sugars, starches and cellulose.
At this point, the bioethanol enters the fuel refinery process where additives are mixed in or the bioethanol is added to conventional fuel to serve as a replacement for petroleum.
Recently, the government changed the standard formulation of petrol in the UK to add twice the amount of bioethanol to it. This new E10 petrol is claimed to reduce carbon dioxide emissions by up to 750,000 tonnes a year, with little impact on modern cars.
Indeed, it is believed that most current cards manufactured since 2011 could use fuel mixed with up to 15 per cent bioethanol without the risk of mechanical problems, although the current E5 mix is still available for classic car owners.
9, a:1:{i:0;s:8:”defaults”;}, surface grinding, Could Biofuel Be Produced By Filtering Waste Into Willow?, A study looking into the effects of filtering wastewater into willow trees could help create renewable biofuels, green chemicals & clean water. See more here., A study looking into the effects of filtering wastewater into willow trees could help to create renewable biofuels, green chemicals and clean water, whilst at the same reducing a growing problem caused by contaminated water., field_544dcaa8220f0, , field_543e9601d7f94, 59