ME graduate student launches new company

Andrew Friend headshotA mechanical engineering graduate student is bringing the Latin word renovo to life on Iowa State’s campus. Translated to English, renovo means to repair or restore, and it’s the underlying concept of Andrew Friend’s company Renovo Fuel Technologies.

The company is based on Friend’s thesis research in renewable fuel. “We are hoping to market an energy product for use in the coal industry that would allow coal power plants to burn renewable fuel in their boilers,” Friend says. “I chose the name renovo because I think of my process as renewing or remaking coal combustion.”

Consulting with Friend on his research efforts and the start of his company are Robert Brown, Anson Marston Distinguished Professor of Engineering, Gary and Donna Hoover Chair in Mechanical Engineering, Iowa Farm Bureau director of the Bioeconomy Institute, director of the Center for Sustainable Environmental Technologies, and professor of mechanical engineering, chemical and biological engineering, and agricultural and biosystems engineering; and President of Breen Energy Solutions Bernard Breen. As Friend worked out his idea, Brown and Breen gave him insight into the renewable fuels and coal industry and offered their guidance and support along the way. Also working with Friend on product development was R. Christopher Williams, professor of civil, construction, and environmental engineering.

“The renewable boiler fuel developed during my thesis research proved to work so well that I figured starting a company was inevitable,” says Friend. He started Renovo Fuel Technologies to enter in the John Pappajohn Iowa Business Plan Competition in April. Unfortunately, his proposal was not accepted for the final stages of the competition, but that didn’t hinder Friend from pressing on with the launch of his new company.

Friend’s confidence in the acceptance of his technology comes from the energy generation structure of the United States. Currently, the U.S. Energy Information Administration identifies coal as the leading form of electricity, supplying about 45 percent of United States power generation. “Coal will remain the most reliable form of baseline electricity generation for the foreseeable future,” says Friend. “With that in mind, power plants should be looking at ways to burn renewable fuel in their boilers to reduce harmful emissions.” The harmful emissions Friend mentions include a large amount of pollutants like carbon dioxide (CO2), sulfur dioxide (SO2), heavy metals such as mercury, and acidic gases such as hydrogen chloride.

Preliminary experiments of using alternative fuels in coal boilers have not been very successful. Attempts to burn a mixture of wood chips and coal was found to be ineffective because wood has low bulk and energy density, which requires large amounts of wood fuel to be brought to the power plants and increases fuel transportation costs. Additionally, alkali metals found in wood can cause fouling and slagging issues in the boilers.

Coal-Bio-oil Pellets, 27% Bio-oil
Coal-bio-oil pellets, made with 27% bio-oil

Other biomass sources, such as corn stover and switchgrass, offer advantages over wood because they have high energy density, but they can’t currently be co-fired in coal boilers because of high alkali content. Friend devised a way around this problem. “With my technology, we can use almost any kind of biomass because we remove the alkali metal during production of our renewable boiler fuel.” he explains.


The process to create Friend’s biorenewable boiler fuel, which comes in the form of pellets, grew from Iowa State’s research into improving fast pyrolysis technology and took many months of fine-tuning. Friend breaks his improved method down into two basic steps. The first step utilizes fast pyrolysis technology by putting biomass such as wood or corn stover into a reactor at very high temperatures (500 C) in the absence of oxygen to prevent burning, which results in three products: biochar, bio-oil, and a gas. Next, the bio-oil is mixed with coal, placed into a mold, and compressed to form a pellet. The pellets consist of up to 35 percent bio-oil and have the same energy density as coal. Friend sees them as a substitute for coal because they can be crushed or pulverized, meaning that they can be handled with existing coal infrastructure.

Pulverized Coal Bio-oil Pellets
Pulverized coal bio-oil pellets

While bio-oil plays a large role in the production of the renewable fuel, the co-product of fast pyrolysis, biochar, can be placed into soils, having a positive impact on the environment. Friend explains that biochar acts as a fertilizer because of the carbon, nitrogen and alkali metals found in the material. The biochar can also be used for carbon storage because it remains in the soil for thousands of years, reducing the levels of CO2 in the atmosphere.

Friend says the direction of his company will not be to create the bio-oil or make the pellets directly but rather to manage the technology. “We hope to be a consulting engineering firm that leverages our patents by providing engineering services, such as designing a facility for manufacturing the pellets, but not necessarily operating the manufactory,” explains Friend.


The research behind Renovo Fuel Technologies was motivated by the increasing regulations associated with the renewable portfolio standard (RPS). Each state has its own RPS that requires a certain amount of renewable electricity be burned or sold. Iowa’s requirement is that MidAmerican Energy and Alliant Energy generate a combined total of 105 megawatts of renewable energy. Since 1997, Iowa has met this standard, but as the demand for electricity increases, Iowa’s RPS may be redefined to encourage the development of renewable energy.

The U.S. Environmental Protection Agency (EPA) is also considering regulations for CO2 emissions, which could make Friend’s technology more valuable. “If the EPA enacts CO2 regulations, power plants will begin scrambling for ways to reduce their CO2 emissions. Burning my pellets is one way they could do this, and they would be burning renewable energy to meet RPS at the same time,” explains Friend. In this scenario, using the proposed biorenewable pellets would also save power plants money because they wouldn’t have to add expensive retrofits to remove carbon from their emissions. The pellets can also be used to meet the new EPA standards for the reduction of nitrogen oxides, heavy metals, sulfur, and acidic gases.

With all the advantages of his product, Friend expects a successful future for his company. After he graduates this fall with his master’s degree, he plans on beginning test burn demonstrations that will allow the coal industry to see the effectiveness of the product. Although it is not official, he says the power plant at Iowa State seems interested in being a test site, and adds that it will take time to integrate the pellets into industry. “It will be two to five years before my product is used on a large scale because of the lack of fast pyrolysis infrastructure necessary to produce the bio-oil for the pellets,” Friend says.

Friend has presented his product to a few companies and is currently applying for grants such as the Small Business Innovation Research grant. His thesis for graduate school is based on perfecting his product, and he hopes to test a variety of different compositions to find the perfect pellet. “It will be interesting to see the advancements made to my product, but as for the near future, I will continue to stay focused on getting my company’s name out there,” says Friend.

4 thoughts on “ME graduate student launches new company

  1. I’m always glad to see imaginative solutions coming from ISU students and grads. Having worked for one of the major US boiler companies for over 41 years, I would like to add these observations:

    Unless the composition of the biomass used to produce the oil is radically different from oil or coal, the CO2 production related to release of BTU in combustion will be the same as for coal or oil.

    The pellets of necessity use pulverized coal as part of the mix. Would it make sense to fire the oil via atomizers in the coal burner, or even in separate burners? The technology of burning pulverized coal is very mature, as is firing oil.

    Production of the biomass oil and the other products requires high temperatures, which must be produced by an energy source. When considering the energy requirements of the biomass process along with the other elements of firing a boiler, is there a net saving?

    Consideration of the elements in the original biomass material, such as corn stover, is most appropriate. Slagging and fouling of boiler heat transfer surfaces is a very real concern. For example, there are some central Illinois coals that are unsuitable for utility boiler use because of extreme fouling. Variations in slagging and fouling characteristics can create major problems in boilers designed for significantly different coals or other fuels.

    I applaud Mr. Friend’s efforts, and wish him well in his efforts.

  2. In response to Mr. Clifton, I thank him for his comments.

    He is correct – the amount of CO2 resulting from the combustion of the pellets, or even just the bio-oil, is the same as the combustion of coal. The real carbon savings comes in the fact that the biochar produced from fast pyrolysis is stored in the soil for many years, perhaps thousands of years. This is true for many biofuels as well. The combustion of ethanol produces comparable amounts of CO2 to that of straight gasoline. The reduction in carbon emissions is in the growth of the biomass, or in our case, in the production of biochar.

    Many different companies have attempted to directly burn bio-oil in boilers. The problem with this method is that bio-oil ages over time (meaning solidification and phase separation), especially when heated. It’s very difficult to store or transport bio-oil. My product can take bio-oil from any producer and create a homogenous pellet. The mechanism of bio-oil aging is a plus here because the pellets get stronger over time.

    Fast pyrolysis produces three products – bio-oil, biochar, and a weak syngas. The syngas and part of the biochar can be burned to provide heat needed for the fast pyrolysis reactions to occur. The amount of energy consumed in the production of the pellets is an issue. However, the real motivation for this product is regulations from individual states and from the federal government. This is true for many renewable energy sources – including wind energy. Governmental regulations and sometimes subsidies level the playing field for emerging renewable technologies as they attempt to compete with fossil fuels in the marketplace.

  3. I would like to correct an error in my post on August 23, 2011.

    I stated that “the amount of CO2 resulting from the combustion of the pellets, or even just the bio-oil, is the same as the combustion of coal.” While the combustion of the pellets does produce CO2 as a byproduct, the amount of net CO2 produced by the pellets is substantially lower than that of traditional coal. This is because the biomass used in the production of the pellets removes CO2 from the atmosphere during its growth cycle. The carbon is then reinserted into the atmosphere when the pellets are combusted, and the cycle is continued with biomass again removes the carbon from the atmosphere. A net removal of CO2 occurs when biochar produced from fast pyrolysis is stored in the soil for many hundreds of years as a carbon sequestration agent, and a soil amendment.

  4. Dear Sir
    Sub: Separation of HCL and sulphur dioxide gas

    I having a process where organic acid is chlorinated with thionyl chloride to get the acid chloride and off gas mixture of hydrogen chloride and sulphurdioxide are absorbed in water followed by caustic soda solution scrubbers. As it is not environment friendly we would like separate the gases as anhydrous hydrogen chloride and sulphur dioxide as this is having demand in the market.

    Please give your offer if you have developed the technology for the separation.
    Thanking you

Comments are closed.