MSW is complex. It is neither homogeneous nor fully convertible to energy. It is not the easiest material to turn into something useful, but Craig Stuart-Paul, CEO of Fiberight, has the creative vision to see its potential. With experience in the recycling and waste management business he is uniquely positioned to benefit from emerging
technologies creating a new and green business opportunity.
With this background Fiberight, founded in 2007, is focusing on turning “black bag” 
MSW into next-generation biofuels. The company’s process separates, cleans, and processes the items we throw away into an organic fraction, a hydrocarbon fraction, and an inert fraction. Most of the organic fraction is converted into cellulosic ethanol, the hydrocarbon (plastics) into electricity, and the inert into recyclables and other beneficial products.
Sorting is key
The first step on the road to making cellulosic ethanol out of MSW is to fractionate the waste stream into 4–5 distinct materials. Two of the materials are organic – a biopulp and a bioliquid.It is the biopulp fraction, making up about 45% of the MSW, which is used today to produce cellulosic ethanol.
Sorting the MSW is a key step in the process. “You can’t just back up a garbage truck into an ethanol machine and add some enzymes,” says Craig Stuart-Paul. “The core process really focuses on taking a nonhomogeneous feedstock and creating a washed and pretreated, homogeneous feedstock optimized for enzymatic hydrolysis.”
After sorting, washing, and pretreating the biopulp is converted into sugars before further fermentation into cellulosic ethanol. To do this Fiberight relies on Novozymes Cellic® CTec2 for hydrolysis of lignocellulosic materials. Cellic can be used on a variety of feedstocks such as corn cobs, MSW, wheat straw, and sugarcane bagasse.
“When we were originally developing our Cellic enzymes, I must admit MSW was not the first feedstock on our minds,” says Cynthia Bryant, Global Business Development Manager at Novozymes. “We were of course primarily focusing on corn cobs and stover, but our Cellic products are robust and, together with Fiberight, we have found that Cellic works quite well on the feedstock in their process.”
As the technologies for cellulosic ethanol are commercialized, producers such as Fiberight will continue to rely on higher-performing enzymes. Novozymes’ effort in cellulosic ethanol is the largest R&D endeavor in the company’s history with over 150 people working on developing solutions.
“We started in 2000, and in February of this year we delivered on our promise – to have the first commercially viable enzymes for cellulosic ethanol by 2010,” says Cynthia Bryant. “The launch of Cellic CTec2 and HTec2 in February offered the industry an average 1.8X performance increase over a variety of feedstocks, which allowed our partners with the most advanced processes to reach an enzyme use cost of USD 0.50/gal. Our focus is now to cooperate with our customers on improving the total production process, and see how the enzymes can play an even larger role in driving down production costs.”
Commercialization goals Fiberight chose Novozymes as its enzyme partner because it needed a company that could not only supply the proper enzymes but also help it to achieve its goals toward commercialization of its process.
“Novozymes was very willing and open to working with Fiberight’s technology and came out to our facilities in Blairstown, Iowa, and Lawrenceville, Virginia, to see our technology first hand,” says Craig Stuart-Paul.He adds that the quality and reactivity of Novozymes’ enzymes work well with Fiberight’s biopulp feedstock and enzyme recycling processes.
What about the rest?
Besides the 45% converted to cellulosic ethanol, other parts of the MSW are utilized in Fiberight’s process. 15% is mixed plastics and organic liquor (the hydrocarbon fraction), which is processed for energy production. 8% is recycled or processed into coproducts like fertilizers or animal absorbents (pellets). The rest is unusable waste, which is shipped to a landfill. In total the process recovers 80–90% of the material, leaving less than 20% to be sent to a landfill.
Fiberight sequesters the energy it produces from the hydrocarbon fraction and uses it to power the plant. This results in its biorefineries having the added benefit of being a net energy provider. Fiberight’s clean technology offers an 80% reduction in greenhouse gas emissions over the production of petroleum-based fuels.
“Our plants require zero input – we’re not taking any natural gas or electricity off the grid to make fuel,” says Craig Stuart-Paul. “Using our processes, there is enough energy from the hydrocarbon fraction to not only provide enough power for our own plant, but to net export too.”
Future focused
For each ton of MSW 85 gallons of cellulosic ethanol can be produced. And when you consider that the US generates approximately 170 million tons of excess trash each year, the potential is significant.
Fiberight is one of the few companies making biofuels from waste today. In November 2009, Fiberight purchased a dry-mill corn ethanol plant in Blairstown, Iowa, with the intention of retrofitting it to demonstration-scale operations. In May 2010 the company commenced production in Blairstown, the United States’ first commercial cellulosic ethanol plant, using enzymatic conversion technology and MSW as feedstock.
The Blairstown biorefinery is currently ramping up cellulosic production and anticipates installing optimized MSW processing and pulp pretreatment processes early next year. At full production the plant will process more than 350 tons of waste into ethanol daily. The feedstock used is paper pulp wastes, industrial wastes, and MSW.