Revolutionizing the Production Process

In 2004, as a follow-up to the development of the pyrolysis process, University Professor Christian Roy and his student Richard Cranford began to explore the possibilities of creating a unique membrane for the purification of syngas. Their efforts evolved into Quebec-based Vaperma Inc. a company specializing in the development and commercialization of advanced gas solutions for the production of ethanol, biodiesel and natural gas. Now, with its innovative membrane technology in hand, Vaperma looks to revolutionize the biofuels industry.
By Khalila Sawyer | November 13, 2007
Vaperma Inc.'s hollow fiber polymeric membrane is a made-in-Canada technology that represents a new dewatering process for the production of fuel ethanol. The trademarked hollow fiber technology called the "Siftek" membrane allows for the highly selective separation of water from various gas mixtures and organic vapors. The heat-and solvent-resistant membranes offer an alternative to conventional ethanol dehydration processes and the removal of carbon dioxide (CO2).

The membrane contains approximately 15,000 hollow polymer fibers that are cut into two-meter lengths and are embedded, bundled and packed into a single removable cartridge. The cartridge is then housed in a module and is inserted into a pressure vessel. The membrane itself is composed of an inner and outer layer each with its own properties. The inner or active layer is where the separation occurs, while the outer or porous sublayer draws the water vapor out. Both layers are no more than 0.2 millimeters thick.

How it Works
When a wet, pressurized gas flows through the membrane, water vapor is absorbed by the inner layer and is then drawn out and diffused into the outer layer. During the ethanol production process, the fuel is dewatered by selective permeation of water vapor through the membrane. The water vapor is better able to permeate across the membrane at a much greater flux than ethanol because of the relatively high absorption and diffusion rates of the polymer formulation of the fabrication process.

After the initial evaporation of the ethanol/water feed, the remaining gas has 40 percent to 60 percent ethanol content. The blend passes through the first membrane module where 90 percent of the water is removed. The water is then pumped out, condensed and directed toward the front end of the plant. The remaining fuel flows through a second series of modules where any remaining water is removed. The result is a 99 percent pure fuel-grade ethanol product. Vaperma's unique process has the potential to dramatically improve the ethanol production process. With no distillation of the ethanol/water blend after evaporation needed, ethanol producers could see energy savings as high as 40 percent by replacing the distillation column and the molecular sieve units used in a conventional ethanol plant. Energy savings are realized mainly because of the membrane's ability to efficiently remove large amounts of water in a continuous process without a change in phase coupled with an advanced heat recovery concept.

The entire process is completed in one continuous step and less than 2 percent of the ethanol is recirculated compared with 38 percent to 48 percent with molecular sieves. "This is a net savings of 1.7 cents per liter (7 cents a gallon) for the ethanol producer," says Claude Letourneau, president and chief executive officer of Vaperma. In addition, the technology is easily integrated into new or existing facilities, requires approximately one-third of the space used for distillation and molecular sieve units, and can be easily expanded by installing additional membrane modules. Since the back end of any ethanol process is where the water is driven off, it would apply to any ethanol production procedure. The Siftek process can also be applied to any type of biomass feedstocks such as corn, sugarcane, wheat and cellulosic biomass. Lastly, no liquid waste is generated as the permeate is mostly water that can be recycled to the front end of the ethanol plant. This reduces the amount of makeup water.

Current Projects
Recently, Vaperma partnered with GreenField Ethanol, Canada's leading ethanol producer, and EnCana Corp., a North American unconventional natural gas and integrated oil sands company, to research and test the Siftek membrane technology. Talks between Vaperma and GreenField initiated two years ago when the companies considered installing a demonstration plant at GreenField's Tiverton, Ontario, ethanol facility.

"[Vaperma's] aim was to convince GreenField of three things: that the Siftek membrane would perform in such a way that it would not dissolve in ethanol, that it could create 99 percent ethanol purity, and that we could deliver a system that could easily adapt to their facility," Letourneau says. "The project was deemed successful within the first six months, which demonstrated the stability of the polymer membrane."

Vaperma's precommercial membrane spinning facility went on line soon afterward in August 2006 and spun enough fibers to enable testing at a larger demonstration facility in Tiverton. The resulting project was the first large-scale demonstration of the membrane technology for dewatering ethanol in North America.

GreenField was so enthusiastic with the first phase, that Vaperma will expand the second phase of its demonstration to GreenField's Chatham, Ontario, location. In the second phase, Vaperma will tweak its beer column to see if it can increase its current 40 percent to 60 percent ethanol content to 50 percent to 60 percent after evaporation of the ethanol/water feed occurs. "As Canada's leading renewable fuels producer, GreenField was eager to test the Vaperma process since it would save money and help the environment," says Robert Gallant, president and chief executive officer of GreenField. "And while saving money appeals to any business, the second factor was equally important because it is consistent with our vision to do business in the most environmentally responsible manner possible."

According to Pierre Ct, chief technology officer of Vaperma, who delivered a lecture on the successful trial demonstration in Tiverton at BBI International's 2007 Fuel Ethanol Workshop & Expo after corn, steam is the most important cost in the production of ethanol, representing approximately 15 percent of the total ethanol production cost.

"The unit in Tiverton used substantially less energy and therefore fewer greenhouse gases were created in the processreducing the plant's CO2 footprint," Gallant says. "While our plants are all extremely efficient, the less natural gas we use to make steam, the better for the environment." In addition to its research collaborations with GreenField, this summer Vaperma opened its new 22,000 square-foot research and technology center for the development and pilot testing of clean energy gas separation membranes in St-Roumald, Quebec. The facility will be primarily used to develop, test and improve the Siftek membrane. The center will be the hub for the manufacture and design of the membrane. It will also house the company's headquarters, engineering department, and experimental lab for membrane production, as well as an analytical lab for quality control and a precommercial membrane production line. Funding support came from Sustainable Development Technology Canada, Encana's Environmental Innovation Fund and Natural Resources Canada, who contributed a collective $7 million toward the project.

Outlook for the Future
As Ct expressed in his lecture, the new membrane technology will become an attractive solution to ethanol producers for a number of reasons. Most importantly while ethanol producers cannot control the cost of raw materials, they can reduce the processing costs with innovative technologies. Vaperma expects that the new membrane will appeal to ethanol producers in North America and Brazil to meet the growing needs of the ethanol industries. "Our first market is the Canadian ethanol industry, specifically GreenField Ethanol," Letourneau says. "After that, we hope to sell worldwide to all ethanol producers." The company has already been in talks with a number of U.S. companies and is strategically positioning itself with the sugarcane industry in Brazil.

At present, Vaperma sees no major obstacles before its Siftek membrane becomes a commercial product in 2008. The company is moving right along, according to Letourneau, and has already secured the proper funding. The company's only challenge will be to balance project development, testing and manufacturing, which Letourneau says all companies deal with. Some industry competitors are also researching similar products. Mitsui & Co. Ltd., which is involved in energy-related business activities and providing stable supplies worldwide, is aggressively marketing a ceramic membrane, one that Letourneau thinks has the same possibilities as Vaperma's polymer membrane but with the drawback of higher capital costs. Despite other research and developments made by the competition, Vaperma remains optimistic about its new Siftek membrane with industrial-scale commercialization projected for next year.

Khalila Sawyer is the managing editor of Biofuels Canada. Reach her at ksawyer@bbibiofuels.com or (519) 576-4500. This feature was reprinted from the October/November 2007 issue.