Researchers have found a way to produce a higher quality, more stable fuel from biowaste, 

such as sewage, that is simpler and cleaner than existing methods.

"This  puts  biofuel  closer  to  being  a good substitute for fossil fuels," said  Hua Song,  an 

associate  professor  of  chemical  and  petroleum engineering at the University  of  Calgary.

Song and his research team recently published the results of their research conducted at th

e Canadian Light Source in the journal Fuel.

"The  world  energy  market  is  currently dominated by fossil fuels. With increasing concern 

surrounding climate change and dwindling resources that are associated with the use of fos

sil fuels, renewable energy sources are becoming increasingly desirable and are currently th

e fast growing energy source," wrote Song in the research paper.

Currently,  biowaste is converted into biofuel in a complex two-step process. The biomass is 

first converted into a biocrude oil using a chemical and thermal process. Crude oil, in general, 

is oil that has not yet been refined and still contains impurities. The second stage is a form of 

refining  i n  which  hydrogen is added under high pressure and heat, and serves to remove 

contaminants such as sulfur, nitrogen and oxygen. However, hydrogen is expensive, the two 

stages are energy intensive, and carbon waste is left in the form of char and CO2 emissions.

A process to reduce reliance on fossil fuels that still produces the harmful greenhouse gas is 

counterproductive. Song and his team set out to simplify the conversion process in a way that 

is sustainable, cost-effective, and clean.

"In our work, we've developed a process which simultaneously produces and upgrades bio-oil 

in one step and without the need for high pressures," says Song.

The  researchers  used  methane instead of hydrogen for the purification process and they 

used it directly in the crude stage, but they had to chemically remove the hydrogen from the 

methane during the purification process since hydrogen is still needed to remove impurities.