The CelloFuel Portable Biomass Refinery produces valuable products from biomass.
We have two inter-related projects that share patented technologies:
1) Solid-state fermenting of sugar beets, sugarcane and sweet sorghum and effiently extracting the resulting ethanol
2) Extracting larch arabinogalactan (LAG) and taxifolin (DHQ) from larch wood chips
Our technologies are based on the observation that it's very expensive to transport sugar-rich biomass long distances to be processed, and that the residuals from processing are valuable when kept on the farm and used as animal feed, for anaerobic digestion, and for fertilizing soil.
Our patented technologies for doing this are described in detail in these three patents which have been granted in numerous countries:
Our technologies are based on the observation that larch wood chips are much more valuable for making pulp and paper if the arabinogalactan and taxifolin are first removed. In addition, the arabinogalactan and taxifolin are quite valuable.
Our patented technology for doing this is described in detail in this patent which has been granted in numerous countries:
Larch arabinogalactan and taxifolin have many uses and have been approved worldwide for human consumption and as a component of animal feed. About 4,000 tons per year are currently produced worldwide, by Lonza and Ametis.
A peer-reviewed clinical study showed that larch arabinogalactan decreased the incidence of cold episodes by 23%. Reducing the cost of larch arabinogalactan can bring the health effects of larch arabinogalactan to the masses (it's currently fairly expensive). Another use of larch arabinogalactan is as a replacement for antibiotics in animal feed. To become widely used in animal feed it needs to be produced less expensively.
The CelloFuel technologies can produce larch arabinogalactan (LAG) and taxifolin (DHQ) from larch wood chips less expensively than existing production technologies.
Larch arabinogalactan can eliminate the need for antibiotics in chicken feed, which makes it possible to sell chicken as organic (which commands a 50% price premium over chicken fed with antibiotics).
About 35% of trees in the world's Boreal forests (Taiga) are larch trees. The pulp and paper industry is growing but larch is less useful than other softwoods because more chemicals are needed to make it into paper and because it's more difficult to bleach.
This is explained in more detail by Wenming He in 2013: "Larch is a primary raw material for pulp and paper industry in China. The advantage of larch is the long fiber length, its excellent growth rate, and its high adaptability to cultivation (Kojima 1996). However, its wood is characterized by thicker cell walls and higher extractives contents than in the case of other raw materials. Moreover, it is easily attacked by fungi during storage leading to blue colors. The lower brightness of larch pulps, usually 50–60% ISO, is a heavy shortcoming, which limits its usage. ... The major reason for the low SCMP brightness of larch is the presence of flavonoid polyphenols in the heartwood, which cause serious darkening in alkaline milieus (Zou and Jiang 1990; Liu et al. 2002)."
Our solution is a technology that efficiently removes the arabinogalactan and flavonoid polyphenols (taxifolin) from wood chips without reducing the quality of the paper fibers. More wood is then available for making paper pulp and arabinogalactan is then an additional revenue stream for the pulp mill. Our technology can efficiently scale up to the throughput required by even the largest paper mills.
There are several large sawmills in Russia, Canada and the US which process larch. The profitability of these sawmills can be significantly improved by making arabinogalactan from the sawmill residues after producing lumber from roundwood.
About 50% of roundwood is used to produce lumber, and 1/3 of the remainder consists of wood chips. These wood chips contain a significant amount of arabinogalactan and taxifolin, and can easily be extracted using our technology. After extraction, these chips can be used in pulp and paper mills to make high quality paper pulp.
Our technology involves infusing a dilute ethanol solution into larch chips, then using these ethanol-rich wood chips as distillation packing, boiling water at the bottom of the distillation column, recovering ethanol at the top of the distillation column, causing the arabinogalactan and taxifolin to accumulate in the water at the bottom of the column and recovering hydrous ethanol from the top of the column.
Our technology is very energy efficient, with the distillation step requiring less than 1 kWh of low-pressure steam heat per kg of arabinogalactan. This energy costs far less than electrical energy per kWh, and is often surplus (i.e. almost free) in pulp and paper mills.
Our technology is very capital efficient. No screw compressors are needed, no electric motors are needed, no pressure vessels are needed, no vacuum vessels are needed, no pulsating diaphram pumps are needed, no microwave emitters are needed, and no ultrasonic emitters are needed. It is also capital efficient because making and condensing low-pressure steam requires little capital.
Our technology produces wood chips from larch that produces pulp and paper that is much more valuable than unprocessed larch chips. The fibers in the wood chips aren't damaged by screw presses or screw conveyors and the arabinogalactan, polyphenols and other extractives are almost completely removed.
Our technology efficiently recovers the dilute ethanol used, resulting in very low cost of ethanol for each kg of arabinogalactan extracted.
Our technology does not require any modification to existing pulp and paper mills. It needs a bit of space to store wood chips before extraction and to store the extracted (i.e. washed) wood chips for use by the pulp and paper mill.
The first large-scale extraction of arabinogalactan from larch was the "Libby process", named for the city of Libby in Montana and used by the St. Regis Paper company to remove arabinogalactan from Western Larch. One variant used counter-current leaching with water over a 15 hour period and another variant coupled counter-current leaching with screw presses to squeeze wood chips. It is described in: U.S. Pat. 3,337,526 by Mark Adams in 1965. The main disadvantage of this method is that it is very capital intensive, very energy intensive and the screw presses damaged the fibers in the chips, making lower-quality paper.
The next company doing large-scale extractions was Larix, Inc. in Minnesota. (later sold to Lonza). Lonza currently produces about 4,000 tons per year of arabinogalactan and sells this for $144 million per year. Lonza's process uses two stage steaming, water impregnation and compression with two screw presses to extract the arabinogalacten. It is described in: U.S. Pat. 5,756,098 (since expired) and in U.S. Pat. App. 20100056772 (not granted). The main disadvanges of this method are that it damages the fibers in the wood chips so they can't be used to make paper, it is very capital intensive and very energy intensive (lots of electricity for screw presses). This process produces arabinogalactan for about $36/kg.
Several improvements to counter-current leaching and squeezing have been proposed: microwave assisted leaching (China), ultrasound assisted leaching (China), and water hammer shock wave assisted leaching (Russia), all coupled with counter-current extraction to concentrate the arabinogalactan. All of these methods suffer from the technical flaw that microwaves, ultrasound and water hammer shock waves all require more energy per kg of arabinogalactan extracted and require more capital per kg/year of arabinogalactan extracted.
Our partner in Russia, NanoTaiga, gave a presentation on November 20, 2019 about our technology at the Russian Forum for Wet Milling & Industrial Biotechnology Graintek-2019. You can download copies of the presentation in Russian and English.
There are three families of CelloFuel patents for making sugars and ethanol that have been granted in the US and around the world, including the US, EU, Canada, Russia, China, Mexico and Brazil.
We've received laboratory analysis results from Celignis Analytical that shows that our larch arabinogalactan is almost identical to Lonza's ResistAid product.
The cold water soluble part of our sample is 98.3% arabinogalactan, and Lonza's ResistAid is 97.1% arabinogalactan, so our sample is a bit purer than Lonza's. (Taxifolin isn't soluble in cold water.)
This analysis also shows that we extract three times as much taxifolin from larch as Lonza (7.8% in our extract vs. 2.4% in ResistAid).
In a separate analysis, we obtained larch chips after Lonza extracted arabinogalactan, and compared them to the larch chips after our extraction.
We ground up both types of wood chips, bone dried them, soaked them in cold water, then filtered off the water and bone-dried the remainder. Since arabinogalactan is highly soluble in cold water, the weight loss is due to arabinogalactan. This analysis shows that our extraction technique has a residual arabinogalactan content that's almost exactly (within 0.1%) the same as Lonza's technique.
Overall, these test results show that we simultaneously extract arabinogalactan and taxifolin, at a much lower capital cost than Lonza, and with the ability to scale to the size needed by a large paper mill.
We also now have access to a Shimadzu HPLC instrument for analyzing our samples in more detail.
We're doing testing to optimize arabinogalactan extraction from larch wood chips. We're using US Patent 10087411 with a 75mm diameter distillation column to optimize this process.
We're using chips from whole tamarack trunks, and are getting about 7-10% of the chips solubilized in water, depending on which part of the trunk the chips are made from. We just get them from a chip bin, so don't know what part of the tree the chips come from.
We know we're getting all of the arabinogalactan and DHQ (taxifolin) from the chips because when we bone-dry the chips and do a second extraction, there's no further weight loss and the liquid extracted is fairly clear.
There is no damage at all to the wood chips after our process, unlike Lonza's process (crushing the chips) and Ametis' process (ethanol extraction from sawdust). Our process is also scalable to very large scale using large chip bins with steam. A dilute ethanol solution is infused into the chips in the same way (using steam) that sodium hydroxide is infused into wood chips in a paper mill - a very well-understood process. We get an aqueous solution of arabinogalactan and DHQ at the bottom of the column and anhydrous ethanol at the top of the column. This aqueous solution can be directly spray-dried and sold as a product, without further processing.
This demonstrates that our process is a good way to remove arabinogalactan from larch chips so that they can subsequently used in a paper mill, with a very low capital investment.
The arabinogalactan we're producing has the same general appearance and color as the ResistAid larch arabinogalactan produced by Lonza. After we optimize the extraction, we'll send our samples to a lab to perform a detailed chemical comparison with ResistAid. Our process should produce a higher concentration of taxifolin (dihydroquercetin, DHQ) than Lonza's process.
After our technologies infuse yeast into biomass, it ferments and becomes ethanol-rich biomass. The same technology we're using for extracting arabinogalactan from larch chips we also use for removing ethanol from fermented biomass. This is an atmospheric-pressure distillation column with ethanol-rich biomass as the distillation packing.
A 1/3 scale model of the CelloFuel module has been successfully built, and we're beginning construction of a full-size CelloFuel module that is 1 m in diameter and 6 m high (with a build cost less than $2,000). The 1/3 scale model has a volume of 1/2 m3, where the full-size CelloFuel module is 5 m3. Here are some pictures of vertical orientation, horizontal orientation, the top cap and the trunnion.
This is for testing rotation, biomass loading (tilted at 45 degrees) and unloading (tilted at 135 degrees). We've tested with 1800 W of heat using double reflective insulation and found that this is very efficient and cost-effective.
Here is a video of the 1/3 scale CelloFuel module with top cap rotating around the trunnion.
Here is a video showing cutting the metal plate for the top cap with a plasma cutter.