新墨西哥州立大学的教授正在尝试使用奶牛的粪肥和其他固体有机废物生产氢气—— 一种燃料电池的能源材料，有望替代非再生性的化石燃料。
氢气可以通过三种方法获得：热化学法、电化学法和生物法。其中生物学的方法是三种方法中耗能最低、最为环保的可持续发展的方法。
目前，生成氢的方法，如电解法或生物质气化法，都不经济。因为这些方法与使用非再生能源法制氢的能耗差不多。电解法利用化石燃料产生的电流把水分解成氢和氧，而生物质气化法则是在高温条件下，通过几个反应步骤后生成氢。
然而，最近的研究已经证实，生物法用有机肥制氢有可能更为经济。研究人员提出的利用生物过程制氢法唯一需要的外部能源就是阳光。
该项目的首席研究员为土木工程学教授Nirmala Khandan，主要合作开发者是化学工程教授Shuguang Deng和生物学教授Geoffrey Smith。他们的研究得到了美国国家科学基金的资助。
研究人员将开发出从家畜肥料制造氢气的技术并进行示范。此项技术将有两个步骤。第一步，通过厌氧菌的水解和发酵生产出氢气；第二步，由第一步的产物进行光发酵生成更多的氢气。
Khandan解释说，“我们正在利用微生物来将牲畜的固态肥料分解成液态。这个过程就是水解。微生物只能利用液态的物质，它们不能直接分解固态物质。这些微生物有一种生理机制，可以先把固态物质转化成液态，然后消耗掉液态的物质。在消耗液态物质的过程中它们获得能量，同时生成氢和其他副产物。我们试图获得这些微生物所产生的氢。”
该团队的研究还包括建造一个生产氢的反应器。反应器独特的构造有两层，分别针对两个反应步骤。
“这是一种新的处理装置，一种新方法，在其他任何地方都还没有采用，”Khandan说，“据我所知，只有其他三所美国大学在做类似的工作。”
此项研究的成果将带来许多益处，包括保存化石燃料，保护水和空气质量，减少温室效应以及减少对国外能源资源的依赖等。
研究人员计划开发出一种多媒体仿真模型来进行公众教育，对象包括各年级的学生和区域政策制定者。以燃料电池技术和制氢技术为基础，向公众展示如何将来自当地牧场的废物转化为能源。
他们还计划与新墨西哥州的农场和大型农场传统博物馆合作，建立一个永久性的展示区，突出展示氢技术可以减少对石油和天然气的开发与产量，从而提高环境质量。
英文原文：
Imagine an energy source that is efficient, pollution-free, and will never run out. Now, imagine that fuel comes from ordinary dairy cows – specifically, from their manure.
Professors at NMSU are attempting to use cow manure and other organic solid wastes to produce hydrogen – an energy source for fuel cells that could potentially replace non-renewable fossil fuels – in a way that is affordable.
Hydrogen can be produced by three different processes: thermo-chemical, electRochemical or biological. Biological processes are the least energy-intensive and the most environmentally friendly and sustainable of the three.
Current methods of hydrogen production, such as electrolysis or biomass gasification, are not cost-effective because of the amount of energy needed as well as the use of non-renewable energy. Electrolysis uses electricity produced from fossil fuels to break water down into hydrogen and oxygen, while biomass gasification uses a high-temperature process by which hydrogen can be produced after several steps.
However, recent research has suggested that biological production of hydrogen – biohydrogen, made from organic matter – could be possible for a much better price. The biological process the researchers are proposing relies only on sunlight for external energy.
The principal investigator for the project is civil engineering professor Nirmala Khandan. The co-principal investigators are chemical engineering professor Shuguang Deng and biology professor Geoffrey Smith. Their research is funded by a grant from the National Science Foundation.
The researchers will develop and demonstrate a two-stage process to produce hydrogen from cattle manure. In the first stage, hydrogen will be produced through anaerobic hydrolysis and fermentation. In the second stage, additional hydrogen will be produced through photo-fermentation of the products of the first stage.
Khandan explained the process. “We are using microorganisms that can break down the cattle manure, which is a solid, and convert it to a liquid form. That's the hydrolysis part. Microorganisms can feed on only liquids; they cannot consume solids directly. They have a mechanism by which they can convert the solids into liquid first, and then consume the liquid. They consume the liquid to get energy for themselves, while producing hydrogen and other chemicals as byproducts. We want to capture the hydrogen that they are producing.”
The team's research will also lead to the construction of a reactor for hydrogen production. The reactor will be a unique configuration with two stages, one for each process.
“It's a new process configuration, a new method that has not been done in many places,” Khandan said. “As far as I know, only about three other universities in the United States are doing this kind of work.”
Results of this research will have many benefits, including conserving fossil fuels, protection of water and air quality, reducing greenhouse gas emissions, and minimizing dependence on foreign energy sources.
The researchers plan to develop a multimedia simulation model to educate the community, including K-12 students and regional policymakers, on the basics of fuel cell technology and hydrogen, and show how waste material from local dairies can be converted into energy.
They also plan to work with the New Mexico Farm and Ranch Heritage Museum to set up a permanent display that will highlight how hydrogen technology can reduce oil and gas exploration and production in our state, improving environmental quality.
