Page 31 - Fuels & Lubes International 2013 - Q1

required minimum volumes of biomass-based
fuel.
however, with cellulosic biorefining,
companies like Zeachem can produce biofuels
and other chemicals derived from the struc-
tural parts of plants, which are comprised of
cellulose, hemicellulose and lignin. The energy
content in cellulosic biomass is divided between
the fermentable cellulose and hemicellulose
(two-thirds) and in non-fermentable lignin and
other components (one-third). For corn, wheat
and other agricultural plants, the structural
parts of these plants were previously only used
as compost or discarded as waste. In addition,
cellulosic biorefining can use plants not used as
food, municipal wastes, wood and other agricul-
tural wastes as feedstock.
Zeachem, with headquarters in Lakewood,
Calif., u.S.A., has been in the cellulosic and
advanced biofuels and biorefining industry since
its incorporation in 2002 and is poised to domi-
nate the market once it ramps up its production.
The company currently has a demonstration cel-
lulose biorefinery plant in boardman, Oregon,
also in the u.S., producing 250,000 gallons
(946,353 liters) per year. production is projected
to increase to more than 25 million gallons
(94,635,294 liters) per year.
According to walsh, their process “offers
the highest yield, at the lowest cost, with the
lowest fossil carbon footprint of any known
biorefining method.”
Zeachem’s hybrid biochemical and ther-
mochemical process uses naturally occurring
acetogens (bacteria) to breakdown cellulose.
walsh stressed that they use non-genetically
modified organisms and that the bacteria is part
of the natural gut flora found in the stomach
of termites and cows. Their patented hybrid
process allows them to eliminate carbon dioxide
production during the acetogenic process. As
a result, there is a 94-98% reduction in green-
house gas (ghg) emissions compared to regular
gasoline, based on calculations by the u.S. de-
partment of energy (u.S. dOe)/Argonne Labs
greenhouse gas regulated emissions and en-
ergy use in transportation (greet) Analysis.
Compared to corn ethanol’s 21-24%, Zeachem’s
process definitely stands out.
In addition, their process allows them to
use all parts of the feedstock (cellulose, hemicel-
lulose and lignin), thereby maximizing their
yield. based on their calculations, regular corn
ethanol has a farm yield of 150 bushels per acre
per year (bu/ac/yr), producing 2.7 gallons (10.2
liters) per bushel; Zeachem’s advanced cellulosic
ethanol has a farm yield of 15 bone dry tons per
acre per year (bdt/ac/yr), producing 135 gal-
lons (511 liters) per bdt. Comparable cellulosic
ethanol process’ (biochemical, thermochemical
or syngas fermentation) average yield is only 7.5
bdt/ac/yr and 90 gallons (340 liters) per bdt.
Their patented process can use a variety of feed-
stock, such as softwood, switch grass and corn
stover. They currently use hybrid poplar trees as
they have a contract with greenwood resources
(gwr), which ensures continuity of supply and
predictability of feedstock prices.
U.S. government support
governmental regulations and support
in the form of loan guarantees and grants
provide the industry the opportunity to reach
its potential. According to walsh, although
there had been a setback due to the recession in
2008, the advanced biofuels industry is poised to
ramp up production and meet future demands.
Zeachem’s C3 platform is roughly 12 months
behind their C2 platform and is expected to
seamlessly interphase with each other. Their
downstream partners, Valero, p&g and Chrys-
ler, will be utilizing their products from these
来。通过把玉米和甘蔗中的糖份转化为生物燃料，人
们已学会如何释放储存在植物中的能量。第一代生物
燃料，如玉米乙醇，已存在了几十年。然而，食品生产
商和动物饲料生产商，特别是那些采用玉米原料的，
在与生物燃料生产商在争夺原料。
这个关于食品和燃料的争论是非常现实的。有些
人把近期的粮食价格高企归罪于美国的可再生燃料
标准（RFS）强制规定的每年需要使用数十亿加仑的
可再生燃料。他们要求美国环保署（EPA）降低对生
物质燃料的最低数量要求。
然而，有了纤维素生物精制，像Zeachem这样的
公司就可以用植物的结构性器官来生产生物燃料和
其他化学品，这些植物结构含有纤维素，半纤维素和
木质素。纤维素生物质的能量含量分为可发酵的纤维
素和半纤维素（占三分之二）和不可发酵的木质素及
其他成份（占三分之一）。对于玉米、小麦和其他农作
物来说，这些植物的结构性部分之前只用于堆肥或作
为废弃物抛弃。此外，纤维素的生物精制可以利用不
作为粮食的植物、市政废弃物、木材和其他农业废弃
物作为原料。
Zeachem公司的总部位于美国加州的Lake-
wood，自其2002年成立以来，就一直从事纤维素和
先进生物燃料和生物精制业的研究，并随着其产量
的提升将主导这个市场。公司目前在美国俄勒冈州的
Boardman有一座示范性纤维素生物精制工厂，年产
量为250000加仑（946353升）。预计年产量将增加
到超过2500万加仑（94635294升）。
按Walsh所说，他们的工艺“提供了最高的收
率，成本最低，是已知生物精制方法中碳足迹最小的
工艺。”
Zeachem的生物化学和热化学混合工艺使用
天然的acetogens（能生产乙酸的细菌）来分解纤维
素。Walsh强调说，他们采用非转基因生物，而且这
种细菌存在于白蚁和母牛胃中的天然胆汁中。他们获
得了专利的混合工艺可以使生产乙酸的过程中不产
生二氧化碳。因此，根据美国能源部（USDOE）/阿贡
实验室温室气体可控排放和运输中的能源使用分析
（GREET）的计算，与常规的汽油相比，可以减少94-
98%的温室气体排放。与乙醇相比，可减少21-24%
的二氧化碳排放，所以Zeachem工艺具有绝对的优
势。
此外，他们的工艺使他们可以使用原料的任何部
分（纤维素，半纤维素，木质素），因此实现了收率的
最大化。根据他们的计算，常规的玉米乙醇的农场产
量为每年每英亩150蒲式尔（BU/ac/yr），每蒲式尔
可生产2.7加仑（10.2升）的燃料；Zeachem的先进
纤维素乙醇为每年每英亩150干吨（BDT/ac/yr），每
BDT可生产135加仑（511升）的燃料。而纤维素乙醇
工艺（生物化学，热化学或合成气发酵）的平均收率
仅为7.5/BDE/ac/yr和每BDT为90加仑（340升）。他
们的专利工艺可以使用多种原料，如软木、干草和玉
米杆。他们目前与GreenWood Resources（GWR）
有合约，因而使用混合的白杨木为原料，以确保连续
供应和原料价格的可预测性。
美国政府的支持
政府法规和贷款担保和拔款这样的支持为行业
实现其潜力带来了机遇。按Walsh所说，虽然由于
2008年的危机而有所退缩，先进生物燃料业已准备
好快速提高产量以满足未来的需求。Zeachem的C3
平台在进度上落后于C2平台约12个月，预计可以相
互无缝衔接。他们的下游合作伙伴，Valero、宝洁和
31 FUELS & LUBES INTERNATIONAL Quarter One 2013