How Biochar Removes CO2 from the Air -- and Helps Farmers Thrive | Axel Reinaud | TED

翻译人员: 新 陈 校对人员: Yip Yan Yeung

Imagine a farmer growing coffee in Nkongsamba,

想象一下，有这么一个农民

in the Moungo region of Cameroon.

在喀麦隆蒙戈州（Moungo） 种植咖啡豆。

Let’s call him Mr. Ewané.

我们姑且叫他 伊万内先生（Mr.Ewané）吧。

Mr. Ewané lives out of a small plot of land,

伊万内先生靠着一小亩地过活，

growing food to feed his family,

一家人吃的是地里种的庄稼，

and coffee, to earn a very modest income.

伊万内先生靠种植咖啡豆 来获取微薄的收入。

While many of us in the Western world debate about climate change,

我们西方国家大多数人 还在为气候变化争论不休，

Mr. Ewané knows it is real.

而伊万内先生确信 气候变化真实存在。

The rainy season is becoming more erratic,

雨季来临的时间越来越不固定，

impacting his coffee production

他地里的咖啡豆也跟着遭殃，

that has been declining year after year.

每年都在减产。

Mister [unclear] is by no means responsible for climate change.

气候变化绝不是伊万内先生造成的。

His own CO2 emissions are below 200 kilograms per year,

他自己每年排放的二氧化碳 不超过 200 公斤，

while we in the developed world emit 30 to 60 times more than he does.

仅仅占我们发达国家人 排放的 30 到 60 分之一。

Our way of living -- his problem.

是我们的生活方式影响到了他。

The great story is that Mister [unclear] can improve his standard of living

好消息是伊万内可以 提高自己的生活质量。

while removing CO2 from the atmosphere and helping fight climate change.

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。

This is not about trees.

不是通过种植树木。

It's much smaller.

比这还要简单。

Sounds interesting?

听起来还挺吸引人？

Well, bear with me.

且听我慢慢道来。

In order to fight climate change,

为了应对气候变化，

we need to reduce, like crazy, our greenhouse-gas emissions,

我们需要大量减少温室气体的排放，

halving, in the next 10 years,

未来 10 年，

the 50 billion tonnes that we emit annually,

我们要将每年排放的二氧化碳量 从 500 亿吨减少到一半，

and then aiming to halve again in the following decade.

并力争在下一个十年 在此基础上再减少一半。

While reduction is needed,

减少碳排放是必要的，

it will not be enough to get us to zero emissions,

但靠这来实现稳定气候 所需的零碳排放，

[which] is needed to stabilize climate.

远远不够。

There will be, for a very long time, residual emissions,

工业、

航空、农业等领域

from some industrial processes,

产生的残余排放会在未来 很长一段时间内持续存在。

from aviation, from agriculture, etc.

Billions of tonnes of residual emissions,

这些残余排放有数十亿吨之多，

even when we have reduced all that we can.

即使我们已经尽可能在减少了。

So we can't be zero emissions,

因此，我们做不到零排放，

but we can be net-zero emissions:

但我们能做到“净零排放”：

that is, removing from the atmosphere, as much CO2 as we emit annually.

也就是，将每年排放到 空气中的二氧化碳全部移除。

And maybe, one day, remove more than we emit,

甚至，将来某一天， 为了使气候回归稳定状态，

to restore our climate balance.

我们移除的二氧化碳 比排放的还要多，

That's when Mister [unclear] comes into play.

伊万内先生这时就能发挥作用了。

He has been capturing CO2 through the growth of his crops,

他种植的作物在生长过程中一直在

year after year.

年复一年地捕获二氧化碳。

Photosynthesis that drives the growth of crops

促进作物生长的光合作用

is by far the most efficient way to capture CO2 from the atmosphere.

是迄今为止最快的碳捕获途径，

But if nothing is done,

但如果什么也不做的话，

that same CO2 goes straight back into the atmosphere

同样多的二氧化碳

when plants decompose or are burned.

会在植物降解或燃烧时被排放出来。

But the good news is that we can stabilize the carbon

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

contained in the leftovers

from the coffee cherries of Mister [unclear].

固定下来。

That means we can remove CO2 year after year

进而每年都能移除一些二氧化碳，

and help fight climate change.

帮助应对气候变化。

And what if that same technology

如果我告诉你这一技术

would allow Mister [unclear] to improve the productivity of his fields,

还能帮助伊万内先生提高耕地产量，

hence his standard of living?

进而提升他的生活水平呢？

Now you start to see the opportunity.

现在大家能看到其中蕴含的可能了。

It’s called “biochar.”

我们利用的是 “生物炭”（biochar）。

Let me say right away that biochar is by no means a magic wand

我要首先说明生物炭绝不是一个魔棒，

that will take us out of the climate crisis.

轻轻一挥，就能 使我们摆脱气候危机。

It's one of the many solutions to help remove CO2 from the atmosphere.

它是移除大气中 二氧化碳的方法之一。

But if used smartly, it's just an amazing thing.

但是如果使用得当， 它会产生惊人的效果。

Biochar is carbon resulting from pyrolysis,

生物炭是经过热裂解形成的，

that is, heating biomass at high temperature without oxygen.

所谓热裂解，就是 在无氧环境下高温加热生物质。

Any kind of plant-based, dried biomass

任何一种来源于植物的干生物质，

contains about half of its weight in the form of carbon.

所含的碳占自身重量的一半。

And it is this carbon that is extracted and stabilized

我们将这些碳提取并固定下来，

to create biochar.

制成生物炭。

Biochar is essentially carbon

生物炭本质上就是

that was captured from the atmosphere by plants

我们用植物捕获大气中的二氧化碳

and transformed into a very stable form of carbon.

将其转化为稳定形式的碳，

It looks like charcoal powder.

看起来像木炭粉。

The first amazing property of biochar

生物炭具有一种神奇特性，

is that it remains stable for hundreds of years,

可以將碳固定在地下

even if put in the soil,

数百年。

where biomass will normally degrade.

而一般的生物质在土壤中都会降解。

Think about it.

试想一下。

The CO2 captured by plants through photosynthesis

植物通过光合作用捕获的二氧化碳

and converted into biochar

转化成了生物炭，

stays in the soil, and so stays away from the atmosphere,

封存在地下，与大气隔绝

for hundreds of years.

成百上千年。

So we have a carbon removal situation,

这是一个移除碳的好方法，

and this is good for the climate.

有利于应对气候变化。

The second amazing property of biochar

生物炭的第二大神奇特性在于，

is that, when mixed with topsoil, it improves the soil quality,

将它和表层土混合， 可以改良土质，

hence, crop yields.

借此使作物增产。

This is especially true for poor, dry and acidic soils that lack nutrients.

对那些贫瘠、干旱以及 酸性土壤来说更是如此。

Putting carbon in the soil

将碳固定在土壤中

has been known empirically for hundreds of years

改良土质的方法

as a way to improve soil quality.

已经实践了数百年。

It was used in some parts of Amazonia prior to the arrival of Europeans,

早在欧洲人到来之前， 亚马逊部分地区就有使用，

and it's still used today in some parts of Asia.

至今在亚洲的部分地区仍有使用。

Biochar's effects on soil come from its microstructure.

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,

生物炭放大看就像 一块吸收碳的海绵，

with hundreds of square meters of surface per gram of biochar.

每一克生物炭表 面积有好几百平方米。

This ultraporous structure helps retain water and nutrients.

这种多孔结构有助于 保存水分和营养物质。

Biochar also favors the development of microbial life into the soil

生物炭也有利于 土壤中的微生物生长，

that is most needed for plants to absorb nutrients.

而这些微生物是植物 吸收营养元素所必需的。

And last, given its high pH,

最后，由于生物炭的碱性比较大，

biochar helps counter the negative effects of soil acidity.

能够促进土壤酸碱平衡。

Using biochar allows to reduce, or even eliminate,

生物炭可以减少甚至消除

the need for fertilizers,

对化肥的需求，

cutting costs for farmers and helping the environment.

这样一来，农民种植成本减少、 环境也有所改善。

And the great thing is that, given its stability,

特别好的一点在于， 由于生物炭很稳定，

biochar needs to be applied just once,

仅需一次使用，

and its effects last for decades.

效力就能持续数十年。

And then, there's a bonus.

还有一个附带效益。

The production process of biochar generates flammable gases.

生物炭生产过程中会产生可燃气。

Part of those gases are used to heat the reactor

其中一些可以用来加热

where biochar is produced,

生产生物炭的反应器，

and the remaining gases can be used to generate renewable heat or electricity.

另一些可以用来生产 可再生的热能和电能。

So not only the production process of biochar

生物炭的生产

is self-sustained,

不仅能够自给自足，

but it is a source of additional renewable energy.

还能产生额外的可再生能源。

Quite incredible.

太神奇了。

So we have this amazing product that is a climate solution,

这样神奇的产品可以解决气候问题、

an agricultural solution

农业问题

and a renewable energy solution.

和再生资源问题。

And now, you start to wonder:

现在，你肯定要想了：

"How come this biochar thing that he's talking about

“那为什么他说的这个生物炭

is not widely used all over the place?

没有在全球大规模应用开来呢？

What's the problem?"

问题出在哪呢？”

Well, the answer is plain and simple:

原因其实很简单：

costs.

成本太高。

Most biochar produced in the last years

一直以来，大多数生物炭

had to be sold at prices as high as 1,000 dollars per tonne,

需要卖出每吨 1000 美元的高价

to cover production costs.

才能收回成本。

That made biochar uneconomical for most usages.

对于大多数用途来说， 性价比并不高。

And so, despite its wonderful properties, it has remained a niche product.

因此，即使生物炭有这么多优点， 也只有少量市场需求。

But things started to change in the last couple of years.

最近十几年，形势开始发生变化。

The recognition of climate change started to shift our behaviors,

气候变化这一事实使得人们 改变自己的行为方式，

leading companies and states to commit to net-zero trajectories.

很多国家和企业 都参与到净零行动中来。

Some innovative companies

一些创新型企业

committed to an accelerated net-zero trajectory;

为加速净零进程

started to buy, at a high price, biochar-based carbon credits

开始高价购买基于生物炭的 碳信用额（carbon credit），

for their long-term CO2 removal effects.

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,

这样生物炭的市场环境就改变了。

as all of a sudden,

突然之间，

the climate benefits of biochar

生物炭的气候效益

could help subsidize its agricultural usage.

可以用来助力农业生产。

As a consequence,

正因如此，

biochar is emerging as a credible CO2 removal solution,

生物炭作为靠谱的移除 二氧化碳的方法正脱颖而出，

especially that it is one of the very few that are available today for scaling.

何况这是如今为数不多 的可以规模化的途径之一。

The technology is mature.

相关科技成熟了，

The scientific backing is here.

有科学研究背书，

The economics could work.

市场可以运作起来，

And the potential is huge.

还有巨大的发展潜能。

In Africa alone,

仅非洲一处

we estimate that half a billion tonnes of agricultural residues

就大约有 5 亿吨的农业废弃物

are available to produce biochar.

可以用来生产生物炭。

That means about the same amount of CO2

这就意味着等量的二氧化碳

being removed every year from the atmosphere,

可以被从大气中移除出去，

and there are many more billion tonnes in the rest of the world.

世界其他地方还有 更多亿吨计数的二氧化碳。

So let's make biochar a solution at scale.

让我们将大规模推广 生物炭这一解决方案。

For this, we need three things.

为此，我们需要做到三件事。

One, access to biomass.

第一，生物质的来源。

Biochar production requires a large quantity of dry biomass,

生产生物炭需要大量的干生物质。

ideally sourced close to the production facilities

最好产地临近生产工厂，

to avoid transportation costs and emissions.

这样就可以减少运输成本和碳排放。

It needs to be residual biomass

生物炭需要是残余的生物质，

so it does not require additional land to grow it.

因而不需要占用额外的土地来种植。

Most biochar companies today use wood residues,

大多数生物炭公司使用木材废料，

like sawdust or branches,

如锯末或树枝，

to produce biochar.

来生产生物炭。

But many alternatives exists --

但也有很多替代品可以利用.....

in particular, agricultural residues.

特别是农业废弃物。

Two, we need superefficient, 24-7 production systems.

第二，我们需要全天候运作的 超高效生产系统。

The technology exists,

目前有技术能够做到这一点，

but there's still room for improvement.

但是还需要进一步改良。

And three,

第三，

we need to encourage farmers to use biochar

我们要鼓励农民使用生物炭，

so that they can reduce the usage of fertilizers,

这样就可以减少化肥的使用，

and improve crop yields.

提高作物产量。

Many companies, as we speak,

此时此刻，许多公司

are developing biochar-based business

正在不同的地方用各种原料

in a variety of geographies and with a variety of feedstocks.

发展基于生物炭的业务。

I cofounded one of them.

我与人合作创办了一个这样的企业。

We focus on tropical developing countries.

我们关注的是位于 热带地区的发展中国家。

Biomass is superabundant there,

那里农业废弃物形式的生物质

in the form of agricultural residues.

十分充足。

We used an optimized production model,

我们使用的是一种 优化过的生产方法，

with easy-to-operate, midsize production plants,

在易于操作的 中等规模生产工厂进行，

where the pyrolysis reactor looks like a tank wagon.

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,

热带地区的土壤一般 都比较贫瘠、酸性很大，

hence benefit the most from the addition of biochar.

因而加入生物炭 对这些土壤最有好处。

And last,

最后，

energy generation is most needed in rural areas of developing countries,

发展中国家的农村地区 十分需要生产能源，

where, very often, less than 25 percent of the people

那里通常只有不到四分之一的人

have access to electricity.

用得上电。

That's how we go back to Mister [unclear].

这我们就又要重新谈及 伊万内先生了。

We will convert to biochar the leftovers from his coffee cherries

我们将把他的咖啡果渣 转化为生物炭，

so that he can use it in his fields

这样他就能在地里使用生物炭

to improve the quantity and quality of his production.

来提高作物产量和品质。

Mr. Ewané will be able to afford the biochar,

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，

given that it will be highly subsidized by the related carbon credits.

他将能够买得起生物炭。

And the electricity generated will be distributed locally.

而生物炭产生的电力就地分配。

A very circular model,

这样一个闭环模型，

for climate and people,

不仅解决了气候问题， 还提高了人们的生活质量。

now.

就是现在。

Thank you for your attention.

感谢聆听。