The natural process of converting algae to crude oil takes millions of years. But engineers at the Department of Energy's Pacific Northwest National Laboratory carried out this conversion in a lab in a matter of minutes, according to a press release.
Though alga has long been established as a potential source of biofuel, the fuel produced is said to be expensive owing to the complex procedures involved in this conversion. However, engineers at the Department of Energy's Pacific Northwest National Laboratory developed a cost effective way to develop crude oil from algae.
Freshly harvested algae were crushed into pulp using a chemical reactor. After running the system for less than an hour, the engineers were able to create crude oil along with some useful by-products. The crude oil can be converted into aviation fuel, gasoline or diesel fuel. The water produced during the conversion process can be processed further to yield cleansed water along with potassium and nitrogen that can be used to grow more algae.
"Cost is the big roadblock for algae-based fuel," said Douglas Elliott, the laboratory fellow who led the PNNL team's research. "We believe that the process we've created will help make algae biofuels much more economical."
The PNNL team simplified this process and reduced its cost by amalgamating many small chemical processes into one continuous process. The best part of this process is that wet algae can also be used. Most current processes require dried algae and drying the plant can consume a lot of time and energy, making it very expensive.
"Not having to dry the algae is a big win in this process; that cuts the cost a great deal," said Elliott. "Then there are bonuses, like being able to extract usable gas from the water and then recycle the remaining water and nutrients to help grow more algae, which further reduces costs."
Another plus point of the new process is that it eliminates the need to use solvents like hexane to extract the energy-rich oils from the rest of the algae. The new PNNL process subjects the algae to very high temperatures and pressure. This tears apart the algae and converts most of the biomass to fuel.
"It's a bit like using a pressure cooker, only the pressures and temperatures we use are much higher," said Elliott. "In a sense, we are duplicating the process in the Earth that converted algae into oil over the course of millions of years. We're just doing it much, much faster."
The new development opens doors to producing fuel in a cost effective way without damaging the environment.
Watch a video of the process here:
