What do algae and manure have in common?

                    Photo by Jere-me

Both are being explored as renewable sources of crude oil by researchers at the University of Illinois.

                

                Yuanghui Zhang, professor and biological engineer at the U of I, headed the research, which initially began simply as an investigation into waste management methods for hog farmers but opened an entirely new market.

                “We started this project fourteen years ago, and it started as a project to treat swine manure.” Zhang said.  “This was just one way of treating the manure.”

                The system uses a thermo chemical conversion, or TCC, to convert the organic compounds into oil and gas.  This process consists of applying heat to the manure in a pressurized enclosure, which causes the rearrangement of the molecules, thus changing the composition of the matter.

                This results in a crude oil which, once refined, has the same properties as traditional oil and can be used to make any number of petroleum based products, including plastics and transportation fuels.  “This is a crude oil, not an alcohol, not ethanol, not biodiesel,” Zhang said.

                A key component in the method developed by Zhang and his colleagues is markedly different from conventional TCC processes in that it requires neither a catalyst nor the manure to be pre-dried.

                While the process does require a fuel source to heat the organic compounds and convert them into oil, Zhang said that the energy which the process yields is three times greater than the energy input.  Additionally, in his research Zhang was able to achieve a 70 percent conversion rate of manure to oil, or a 50 percent conversion rate to refined oil; however Zhang said that he anticipates that an even greater conversion rate could be achieved with more research into the process.

                However, even at the current rates, this would add a significant amount of profit for hog producers, as well as provide a means of waste management.

                “Our research has now also expanded from swine manure to human waste,” Zhang said.  “And we are also now doing research on using the waste water, animal waste and human, to grow algae, and then convert the algae into crude oil.”

                Growing the algae on the waste water is dual purposed, as not only is it very rich in nutrients, but the waste water needs to be cleaned anyways and the algae does this.

                The process would also be carbon neutral, Zhang said.  “When you extract the energy from the biowaste, the remaining nutrients and CO2 are absorbed by the algae.  Then we convert that algae into more oil.”