生物炭帮助农作物茁壮成长 还可以去除空气中的二氧化碳

中国玉米

His own CO2 emissions are below 200 kilograms per year, while we in the developed world emit 30 to 60 times more than he does. Our way of living, his problem. The great story is that Mister Ewane can improve his standard of living while removing CO2 from the atmosphere and helping fight climate change. This is not about trees. It’s much smaller. Sounds interesting? Well, bear with me. In order to fight climate change, we need to reduce, like crazy, our greenhouse-gas emissions, halving, in the next 10 years, the 50 billion tonnes that we emit annually, and then aiming to halve again in the following decade.

他自己每年排放的二氧化碳不超过200公斤，仅仅占我们发达国家人排放的30到60分之一。是我们的生活方式影响到了他。好消息是伊万内可以提高自己的生活质量，同时还能移除掉空气中的二氧化碳，为应对气候变化贡献力量。不是通过种植树木。比这还要简单。听起来还挺吸引人？且听我慢慢道来。为了应对气候变化，我们需要大量减少温室气体的排放，未来10年，我们要将每年排放的二氧化碳量从500亿吨减少到一半，并力争在下一个十年在此基础上再减少一半。

中国高粱

While reduction is needed, it will not be enough to get us to zero emissions, which is needed to stabilize climate. There will be, for a very long time, residual emissions, from some industrial processes, from aviation, from agriculture, etc. Billions of tonnes of residual emissions, even when we have reduced all that we can. So we can’t be zero emissions. But we can be net-zero emissions. That is, removing from the atmosphere, as much CO2 as we emit annually. And maybe, one day, remove more than we emit, to restore our climate balance.

减少碳排放是必要的，但靠这来实现稳定气候所需的零碳排放，远远不够。工业、航空、农业等领域产生的残余排放会在未来很长一段时间内持续存在。这些残余排放有数十亿吨之多，即使我们已经尽可能在减少了。因此，我们做不到零排放。但我们能做到“净零排放”。也就是，将每年排放到空气中的二氧化碳全部移除。甚至，将来某一天，为了使气候回归稳定状态，我们移除的二氧化碳比排放的还要多。

That’s when Mister Ewane comes into play. He has been capturing CO2 through the growth of his crops, year after year. Photosynthesis that drives the growth of crops is by far the most efficient way to capture CO2 from the atmosphere. But if nothing is done, that same CO2 goes straight back into the atmosphere when plants decompose or are burned. But the good news is that we can stabilize the carbon contained in the leftovers from the coffee cherries of Mister Ewane. That means we can remove CO2 year after year and help fight climate change.

伊万内先生这时就能发挥作用了。他种植的作物在生长过程中一直在年复一年地捕获二氧化碳。促进作物生长的光合作用是迄今为止最快的碳捕获途径。但如果什么也不做的话，同样多的二氧化碳会在植物降解或燃烧时被排放出来。好消息是我们有技术能够将伊万内先生的咖啡果渣中的碳固定下来。进而每年都能移除一些二氧化碳，帮助应对气候变化。

And what if that same technology would allow Mister Ewane to improve the productivity of his fields, hence his standard of living? Now you start to see the opportunity. It’s called biochar. Let me say right away that biochar is by no means a magic wand that will take us out of the climate crisis. It’s one of the many solutions to help remove CO2 from the atmosphere. But if used smartly, it’s just an amazing thing. Biochar is carbon resulting from pyrolysis. That is, heating biomass at high temperature without oxygen. Any kind of plant-based, dried biomass contains about half of its weight in the form of carbon.

如果我告诉你这一技术还能帮助伊万内先生提高耕地产量，进而提升他的生活水平呢？现在大家能看到其中蕴含的可能了。我们利用的是“生物炭”。我要首先说明生物炭绝不是一个魔棒，轻轻一挥，就能使我们摆脱气候危机。它是移除大气中二氧化碳的方法之一。但是如果使用得当，它会产生惊人的效果。生物炭是经过热裂解形成的。所谓热裂解，就是在无氧环境下高温加热生物质。任何一种来源于植物的干生物质，所含的碳占自身重量的一半。

And it is this carbon that is extracted and stabilized to create biochar. Biochar is essentially carbon that was captured from the atmosphere by plants and transformed into a very stable form of carbon. It looks like charcoal powder. The first amazing property of biochar is that it remains stable for hundreds of years, even if put in the soil, where biomass will normally degrade. Think about it. The CO2 captured by plants through photosynthesis and converted into biochar stays in the soil, and so stays away from the atmosphere, for hundreds of years.

我们将这些碳提取并固定下来，制成生物炭。生物炭本质上就是我们用植物捕获大气中的二氧化碳将其转化为稳定形式的碳，看起来像木炭粉。生物炭具有一种神奇特性，可以将碳固定在地下数百年，而一般的生物质在土壤中都会降解。试想一下。植物通过光合作用捕获的二氧化碳转化成了生物炭，封存在地下，与大气隔绝成百上千年。

So we have a carbon removal situation. And this is good for the climate. The second amazing property of biochar is that, when mixed with topsoil, it improves the soil quality, hence, crop yields. This is especially true for poor, dry and acidic soils that lack nutrients. Putting carbon in the soil has been known empirically for hundreds of years as a way to improve soil quality. It was used in some parts of Amazonia prior to the arrival of Europeans. And it’s still used today in some parts of Asia. Biochar’s effects on soil come from its microstructure.

这是一个移除碳的好方法，有利于应对气候变化。生物炭的第二大神奇特性在于，将它和表层土混合，可以改良土质，借此使作物增产。对那些贫瘠、干旱以及酸性土壤来说更是如此。将碳固定在土壤中改良土质的方法已经实践了数百年。早在欧洲人到来之前，亚马逊部分地区就有使用，至今在亚洲的部分地区仍有使用。生物炭对土壤的作用和它的微观结构有关。

When magnified, biochar looks like a carbon sponge, with hundreds of square meters of surface per gram of biochar. This ultraporous structure helps retain water and nutrients. Biochar also favors the development of microbial life into the soil that is most needed for plants to absorb nutrients. And last, given its high pH, biochar helps counter the negative effects of soil acidity. Using biochar allows to reduce, or even eliminate, the need for fertilizers, cutting costs for farmers and helping the environment. And the great thing is that, given its stability, biochar needs to be applied just once.

生物炭放大看就像一块吸收碳的海绵，每一克生物炭表面积有好几百平方米。这种多孔结构有助于保存水分和营养物质。生物炭也有利于土壤中的微生物生长，而这些微生物是植物吸收营养元素所必需的。最后，由于生物炭的碱性比较大，能够促进土壤酸碱平衡。生物炭可以减少甚至消除对化肥的需求，这样一来，农民种植成本减少、环境也有所改善。特别好的一点在于，由于生物炭很稳定，仅需一次使用。

And its effects last for decades. And then, there’s a bonus. The production process of biochar generates flammable gases. Part of those gases are used to heat the reactor where biochar is produced. And the remaining gases can be used to generate renewable heat or electricity. So not only the production process of biochar is self-sustained. But it is a source of additional renewable energy. Quite incredible. So we have this amazing product that is a climate solution, an agricultural solution and a renewable energy solution. And now, you start to wonder: How come this biochar thing that he’s talking about is not widely used all over the place? What’s the problem?

效力就能持续数十年。还有一个附带效益。生物炭生产过程中会产生可燃气。其中一些可以用来加热生产生物炭的反应器，另一些可以用来生产可再生的热能和电能。生物炭的生产不仅能够自给自足，还能产生额外的可再生能源。太神奇了。这样神奇的产品可以解决气候问题、农业问题和再生资源问题。现在，你肯定要想了：“那为什么他说的这个生物炭没有在全球大规模应用开来呢？问题出在哪呢？”

Well, the answer is plain and simple: costs. Most biochar produced in the last years had to be sold at prices as high as 1,000 dollars per tonne, to cover production costs. That made biochar uneconomical for most usages. And so, despite its wonderful properties, it has remained a niche product. But things started to change in the last couple of years. The recognition of climate change started to shift our behaviors, leading companies and states to commit to net-zero trajectories. Some innovative companies committed to an accelerated net-zero trajectory, started to buy, at a high price, biochar-based carbon credits for their long-term CO2 removal effects.

原因其实很简单：成本太高。一直以来，大多数生物炭需要卖出每吨1000美元的高价才能收回成本。对于大多数用途来说，性价比并不高。因此，即使生物炭有这么多优点，也只有少量市场需求。最近十几年，形势开始发生变化。气候变化这一事实使得人们改变自己的行为方式，很多国家和企业都参与到净零行动中来。一些创新型企业为加速净零进程开始高价购买基于生物炭的碳信用额，因为生物炭有移除二氧化碳的长期卓越效果。

That changed the economics of biochar, as all of a sudden, the climate benefits of biochar could help subsidize its agricultural usage. As a consequence, biochar is emerging as a credible CO2 removal solution, especially that it is one of the very few that are available today for scaling. The technology is mature. The scientific backing is here. The economics could work. And the potential is huge. In Africa alone, we estimate that half a billion tonnes of agricultural residues are available to produce biochar. That means about the same amount of CO2 being removed every year from the atmosphere.

这样生物炭的市场环境就改变了，突然之间，生物炭的气候效益可以用来助力农业生产。正因如此，生物炭作为靠谱的移除二氧化碳的方法正脱颖而出，何况这是如今为数不多的可以规模化的途径之一。相关科技成熟了。有科学研究背书。市场可以运作起来。还有巨大的发展潜能。仅非洲一处就大约有5亿吨的农业废弃物可以用来生产生物炭。这就意味着等量的二氧化碳可以被从大气中移除出去。

And there are many more billion tonnes in the rest of the world. So let’s make biochar a solution at scale. For this, we need three things. One, access to biomass. Biochar production requires a large quantity of dry biomass, ideally sourced close to the production facilities to avoid transportation costs and emissions. It needs to be residual biomass so it does not require additional land to grow it. Most biochar companies today use wood residues, like sawdust or branches, to produce biochar. But many alternatives exists, in particular, agricultural residues.

世界其他地方还有更多亿吨计数的二氧化碳。让我们大规模推广生物炭这一解决方案。为此，我们需要做到三件事。第一，生物质的来源。生产生物炭需要大量的干生物质。最好产地临近生产工厂，这样就可以减少运输成本和碳排放。生物炭需要是残余的生物质，因而不需要占用额外的土地来种植。大多数生物炭公司使用木材废料，如锯末或树枝，来生产生物炭。但也有很多替代品可以利用，特别是农业废弃物。

Two, we need superefficient, 24-7 production systems. The technology exists. But there’s still room for improvement. And three, we need to encourage farmers to use biochar so that they can reduce the usage of fertilizers, and improve crop yields. Many companies, as we speak, are developing biochar-based business in a variety of geographies and with a variety of feedstocks. I cofounded one of them. We focus on tropical developing countries. Biomass is superabundant there, in the form of agricultural residues. We used an optimized production model, with easy-to-operate, midsize production plants, where the pyrolysis reactor looks like a tank wagon.

第二，我们需要全天候运作的超高效生产系统。目前有技术能够做到这一点。但是还需要进一步改良。第三，我们要鼓励农民使用生物炭，这样就可以减少化肥的使用，提高作物产量。此时此刻，许多公司正在不同的地方用各种原料发展基于生物炭的业务。我与人合作创办了一个这样的企业。我们关注的是位于热带地区的发展中国家。那里农业废弃物形式的生物质十分充足。我们使用的是一种优化过的生产方法，在易于操作的中等规模生产工厂进行，那里的热解反应器看起来像一辆油罐车。

Soils in the tropics are generally poor and acidic, hence benefit the most from the addition of biochar. And last, energy generation is most needed in rural areas of developing countries, where, very often, less than 25 percent of the people have access to electricity. That’s how we go back to Mister Ewane. We will convert to biochar the leftovers from his coffee cherries so that he can use it in his fields to improve the quantity and quality of his production.

热带地区的土壤一般都比较贫瘠、酸性很大，因而加入生物炭对这些土壤最有好处。最后，发展中国家的农村地区十分需要生产能源，那里通常只有不到四分之一的人用得上电。这我们就又要重新谈及伊万内先生了。我们将把他的咖啡果渣转化为生物炭，这样他就能在地里使用生物炭来提高作物产量和品质。

Mr Ewane will be able to afford the biochar, given that it will be highly subsidized by the related carbon credits. And the electricity generated will be distributed locally. A very circular model, for climate and people, now. Thank you for your attention.

只要伊万内先生从生物炭相关的碳信用额交易中得到大额补贴，他将能够买得起生物炭。而生物炭产生的电力就地分配。这样一个闭环模型，不仅解决了气候问题，还提高了人们的生活质量。谢谢大家的倾听。