Can Biochar Paint the World Green?

I add this recent item on Biochar. This will refresh your knowledge on the subject. I have covered it extensively over the past year or so and it is always nice to see another good survey story.

The principle reason this flies is that in the face of the developed world’s regulatory environment and the clear lack of patentability, most protocols like this run into an irresistible headwind. Familiarity with the literature on zeolites and thence solid crystalline acids immediately suggests the use of activated carbon as a soil additive. It certainly did to me yet I backed off for the above reasons.

Because the Amazonian Indios have conducted a field test over thousands of years, the need for extensive field tests just to show feasibility evaporates and we can now study the effects of thousands of years of such practices on such soils.

Thus concern over scientific acceptance may make you look wise but science in the field makes you look like the guy sitting on the cure for cancer.

Can charcoal paint the world green?

A look at the promising future of biochar

by Myles Estey

October 31, 2008

Amidst growing documentation of global warming and its dangers, a simple method of carbon sequestration has been quietly demonstrating potential to play an integral role in the fight against climate change.

Far from the spectacular engineering of most sequestration methods or industrial greenhouse gas (GHG) capture systems, focus instead lies on very simple ingredients: waste organic matter, a kiln and chunks of charcoal. Interest in how this can not only fight climate change, but also soil degradation, soil toxicity and poor crop yields, continues to build rapidly around the world.

This is not your average charcoal. Originally called Terra Preta de Indio (Amazonian Dark Earth, after its region of origin), researchers today tend towards the term “biochar.” The char product derives from a special burning process called pyrolysis, where organic matter is burned in the absence of oxygen at a temperature between 300 and 600 degrees Celsius. Wood chips, crop residues, manure, food wastes: any and all forms of organic matter can be combusted through pyrolysis to similar results.

The anaerobic nature of this burning partially prevents the release of carbon as a gas, instead leaving a residual char that is extremely rich in carbon: the biochar. The differentiating feature in the two breakdown processes is simple.

Typical combustion of organic matter (burning, incineration), releases nearly all of the carbon as carbon dioxide (CO2) the gas which scientists increasingly identify as the root of the climate change problem. Similarly, when organic materials are left to break down naturally, these same products will release methane, a gas with 21 times more global warming potential (GWP) than CO2 which again fuels the climate change feedback loop. Pyrolysis burning ensures much of the carbon stays as a solid, thus not releasing it into the atmosphere as a gas.

The pyrolysis kilns – which can range from the size of a fist to an industrial facility - have yet another added feature that help mitigate the effects of climate change. Many are designed to harness the heat of the kiln to assist in generating the facility where they are stationed. In other words, while biomass gets treated in a carbon-responsible manner, it simultaneously diminishes the need to draw more power from the grid, which has associated emissions of its own, an added step of efficiency.

Within the actual pyrolysis process, instead of emitting the majority of carbon as gas, the nature of the anaerobic burning permits roughly 50 per cent of the carbon in the combusted product to end up as the carbon-rich biochar. The promising aspect here is that carbon is stable in this state. It can be buried safely in the ground, where it breaks down on the scale of hundreds to thousands of years, boosting soil health while doing so.

As Cornell professor Johannes Lehman – among the more prolific and respected researchers on the topic – writes in the article “Bio-energy in the Black”, the buried biochar has two main attractive features: “a high stability against decay and [a] superior ability to retain nutrients as compared to other forms of soil matter.” This means that as the carbon breaks down in the ground, it makes positive contributions to the soil health. Initial research has shown definitive potential for the char to boost crop yields, reduce soil degradation and offset the presence of dangerous chemicals that have ended up in soil - all fairly high accolades for little pieces of charcoal.

Despite the promising functions of biochar, research on the modern applications of biochar remains in the embryonic phase. To date, all that has been determined is there is enough potential for biochar to warrant further study. Initial observations of how well char has acted when put in soil, and how safe the char is as a carbon storage mechanism, has been a major boon to the burgeoning interest in the topic. Similarly positive results yielded from climate models calculating the extent to which pyrolysis methods of combusting biomass can prevent the release of CO2 into the atmosphere are further propping up interest in pursuing the practice.

With optimistic initial findings, claims have emerged that state even modest application of biochar systems could reduce global greenhouse gas emissions by 10 per cent, that biochar will be the wedge to avert climate change disaster or that biochar will help arrest the onslaught of desertification and topsoil depletion.

Professor Lehman, though himself an ardent believer in the worth of biochar, is insistent that much more research needs to be done to determine exactly what role biochar can play in helping society work towards a healthier planet before definitive claims can be made.

“We need to evaluate the biochar potential at the scale that it needs to be implemented, with solid accompaniment by research to evaluate both its benefits and potential problems,” explains Lehmann. He adds with some chagrin that the money needed to move forward is a drop in the bucket compared to U.S. research money backing biofuel and other carbon sequestration projects.

“I think the technology is at our fingertips,” Lehmann furthers, “if we could just get a few million [in funding] it would make a huge contribution to our understanding.”

Beyond understanding how it will all work scientifically on the larger scale, more also must be done to understand how biochar can work from an economic and policy standpoint. No matter how ecologically beneficial biochar may prove to be, it will go nowhere without industry backing.

Peter Fransham - the Vice President of Technology at Advanced BioRefinery Inc. (ABRI), an Ottawa-based company that works with pyrolysis - is well aware of this. Peter has the unique position of having worked in the small industry for 20 years, a veritable eternity in this young field. Even today, ABRI remains one of only four or five Canadian companies dealing with pyrolysis or biochar.

Fransham believes any decisions to invest in biochar will come down to simple cost analysis: will it bring sufficient financial benefit to those who use it? He offers the sample question of “what is the increase in yields that one will obtain from putting [char] into the field, and how long is the payback for that [individual]?” Being able to answer this question accurately will be crucial to biochar’s direction from here.

“At this point, we don’t really have the numbers to say what the payback is going to be. And that’s where the academic community comes in, to help determine these rates,” Fransham adds. “Can we put this in at this rate, and have this improvement, and generate a positive rate of return for the farmer?” Accurate answers to this question still hang in the balance, and Fransham underlines that determining actual dollar figures on the costs and benefits will be a prerequisite for an industry to grow around the technology.

These steps are being taken, however slowly, and far removed from the limelight. ABRI’s understanding of how the biochar process can work continues to develop in concert with others around the world. Joint research projects in both Canada and the U.S. continue to fuel ABRI with more information about how their two main biomass interests - poultry manure and wood chips - can be reduced through pyrolysis, and used as a marketable product.

Positives outweigh the negatives for Fransham and his company these days, but as he says of any long term success, “biochar has to prove this is something we have to do today, as well as in the future” in order to really flourish.

Lehmann and the academic community around biochar are hoping to do just this. Far more so than Fransham, Lehmann speaks with excitement of the potential for biochar not as a business, but as a means to fight climate change, boost crop yields and enrich soil quality. And it is in these latter three points that most of Lehmann’s work focuses, hoping to find that we may have a way to help us steer off our crash course to a climatic disaster.

However, Lehmann speaks firmly on the fact that biochar will never be the sole answer to curbing global warming. Such a goal, he reminds, will only be realized by reducing the high dependence on GHG-producing energy we see today. He cautions that it is an illusion to think that biochar is a magic solution, instead emphasizing that it can “play a significant role in a portfolio of options” to fight climate change, if done properly. He adds, “it may be the only option that we have right now, today, that can actually have a net withdrawal of CO2 from the atmosphere in a safe and environmentally conscious way.”

This, of course, is hugely important news for anyone even remotely concerned with our planet’s health.
The fact that biochar can conceivably remove CO2 from the atmosphere and make an end product that has its own set of benefits is certainly compelling, to say the least, and more than worthy of the research Lehmann, Fransham and their peers advocate.

If it is even half of what some have predicted, everything from timber mills in the Canadian north, to Australian farms plagued by arid ground, to African villages that rely on dangerous or inefficient combusting methods, to mega-farms in the American northwest could be reaping the benefits of biochar and revolutionizing how we deal with our organic waste. And all the while bringing our atmospheric CO2 to more stable levels.

If research heads in the direction many are hoping it will, there may be a chance yet for charcoal to do something few would have ever guessed of it: make our world a greener place.

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