1490 O’Brien Drive
Menlo Park, CA 94025
tel: (650) 543-8120
email: businessdevelopment@zeachem.com
ZeaChem, Inc. is developing a cellulose-based biorefinery platform producing either ethanol or a broad portfolio of other chemicals. ZeaChem’s indirect approach leap frogs the yield, capital and CO2 problems associated with traditional ethanol production practices and other potential cellulosic based ethanol processes. ZeaChem currently operates a pilot plant at its Menlo Park, CA laboratory.
Process Advantages
ZeaChem’s process combines biochemical and thermochemical platforms producing either ethanol or a broad portfolio of other chemicals. Utilizing a naturally occurring acetogen, found for example in termites, ZeaChem’s process fully utilizes all of carbon. Thus, the energy of all fractions of the biomass ends up in the product.
For every bone dry ton (BDT) of biomass, ZeaChem’s process will produce a theoretical maximum of 160 gallons of ethanol. Accounting for yield per acre, this is 3x more than corn based ethanol processes and ~1.5x more than either biological (enzymatic) processes or thermochemical (gasification) processes.
Technology Overview
ZeaChem’s innovative process was designed for high yield. The company is pioneering biorefinery technology using combinations of biochemical and thermochemical processing steps.
The biochemical processing step converts fermentable sugars in the cellulosic biomass into acetate, which is then recovered from the broth as an ester. The thermochemical processing step converts lignin and other non-fermentable materials in the cellulosic biomass into hydrogen. By combining these two streams in a hydrogenolysis reaction, ZeaChem produces ethanol. Unlike other processes, the Zeachem process uses all fractions of the plant – cellulose, hemicellulose, and lignin, giving it much higher yield.
Our approach allows both fermentable and non-fermentable fractions of the feedstock to contribute chemical energy to the ethanol product. Other approaches have theoretical restrictions that limit ethanol production to 60-100 gallons per dry ton of biomass. The ZeaChem technology will produce fifty percent more ethanol per ton of feed than the current best-in-class technology. Our higher yield dramatically improves process economics, allowing farmers to get more ethanol out of each acre of biomass crop.
Because the yield is so much higher and because energy integration is tighter, the ZeaChem process is friendlier to the environment. Ethanol produced by corn dry milling in the US has a net energy ratio of under 1.6, meaning that fewer than 1.6 units of renewable energy are produced for each unit of fossil energy used in the production the crops and conversion of the crops into fuel ethanol. In contrast, the ZeaChem technology enables a net energy ratio of 10-12. Such high values fundamentally change the nature of any policy debate on the environmental aspects of ethanol as a liquid transportation fuel.
The biochemical processing step can ferment any fermentable sugar, including simple sugars like those found in sugar cane juice, more complex sugars found in corn starch, and the mixed sugars commonly found in cellulosic hydrolyzates. Any material that isn’t readily fermented, such as lignin, can be processed via thermochemical means to produce hydrogen. The result is that the ZeaChem technology is highly flexibile and can be implemented anywhere in the world.