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Wednesday, March 26, 2014

Crowd Funded Low-Tech Cyanide Mitigation, Anyone?


By Josh Kearns

Crowdsourcing is by now thoroughly established as an internet meme. How do I know this? Because I’m aware of it.

Compared to today’s hip and uber-connected Millennials, I’m a hopelessly antiquarian Gen-Xer. I do not and hope to never own a smart phone. (My career aspiration is to eventually go “full Wendell Berry” and refuse to even use a computer.) The only Rock I know is Classic; I don’t even know what “Emo” is (or was); anyway, these days I mostly dig on Bluegrass and Old-Time – you know, “both kinds of music.” I greatly prefer slow travel by train to blasting around the country (and world) stuffed into an airplane. I’ve vowed that my dearly loved ’89 Toyota pickup will be the last car I ever own. (It doesn’t have to last my whole lifetime – just until peak oil drives gas prices out of range of all but the one-percenters…) And I get all giddy whenever a new article comes out in Low Tech Magazine.

With that thumbnail sketch of my corn-pone backwardness, you can understand that by the time an internet trend reaches me, its cutting-edge has long since dulled.

One such contemporary internet meme for which I am late-as-usual to the party is: crowdsourcing support for scientific and research endeavors. I was excited to learn recently about sites such as experiment.com that provide a crowd-funding platform for research projects. This may turn out to be a viable support mechanism for “Chemistry Without Borders” projects, like those we undertake at Aqueous Solutions, which often are difficult to fund through conventional academic channels.

I would be interested to hear from any researchers who have experience with crowd funding their work – what do you think? Pros? Cons? Groovy? Or a total drag?

One thing about doing fieldwork is that practical and applied research projects seem to constantly throw themselves at you. I wrote about one in last week’s post, calling on the (Bio-) Chemists Without Borders community to help us hack a cheap-and-easy field E.coli water tests.

Another nugget (pun intended) I have been mulling over for a while now is how to develop a low-cost treatment system for village water sources impacted by gold mining effluents.

Burma is a country with a lot of mining operations and not a lot of environmental and public health protections.[1] Cyanide – a toxin so potent that it gets its own chapter in The Poisoner’s Handbook[2] – is by far the most common lixiviant (extraction agent) used in gold mining, accounting for about 90% of world production.[3] It’s also used in the recovery of base metal such as copper, lead, and zinc.


Gold mine in Burma.
Image source: http://thevelvetrocket.com/2011/02/23/photos-of-the-day-gold-mining-in-myanmrarburma/

A number of physical and chemical mechanisms influence the fate of cyanide released to the environment, including volatilization, sorption to sediments, oxidation, hydroloysis, photolysis, and biodegradation.[4] Cyanide reacts relatively quickly to for thiocyanate, which is less toxic but much more persistent.[5]

In my work and travels in SE Asia, I’ve encountered numerous individuals and communities concerned about their exposure to mining effluents. These have included complaints of symptoms consistent with exposure to thiocyanate, including skin, eye, and respiratory irritations, nausea and stomach ulcers, and possible neurological effects.

Without epidemiological surveys it is impossible to confirm exposure to cyanide or cyanate species, and the predominant exposure routes (occupational, food and drinking water, dermal exposure e.g. during bathing and clothes washing, etc.). But there is little doubt that mining in Burma heavily impacts water quality at the local and even regional scales, and that proper control measures on cyanide release to the environment are non-existent.

It turns out, though, that many garden-variety indigenous microbes are capable of uptake, conversion, sorption, and/or precipitation of the cyanide, cyanate, and thiocyanate.[3] Microbial species living in mine tailings piles can become acclimatized to elevated cyanide and thiocyanate. Some species, for example the ubiquitous Pseudomonas, are capable of using cyanide and thiocyanate as their source of carbon and nitrogen and are particularly effective at degradation.

A variety of fixed-bed bioreactors for cyanide/thiocyanate degradation have been developed and tested at the lab, pilot, and full scale with encouraging results.[5] One study found activated carbon to be a favorable biofilm support medium, due to its high porosity and surface area for microbial colonization, and its capacity for adsorption of cyanide and thiocyanate complexes.[6]

This has led me to wonder if we could develop a low-cost fixed-film bioreactor using locally generated adsorbent biochar as the support medium, and a cyanide-acclimated microbial inoculum harvested from local gold mill tailings.

It’s a tough question whether such a system could produce drinking-water-quality-water, especially in the case of source waters that are very heavily impacted by mining effluents and therefore are likely to contain also a host of toxic metals. Although, thiocyanate readily forms complexes with many transition metals, so some metals removal may also be achievable through co-precipitation. Furthermore, biochars have also been demonstrated as effective for some uptake of some heavy metals.[7]

Could the water be made safe for drinking and food preparation is thus a totally open – and difficult – question. In my experience, though, many affected communities have worked to secure alternative sources of water for consumption, but still rely on mining impacted waters for bathing, personal hygiene, and clothes washing. A cost-effective treatment system could, therefore, alleviate dermal exposures, or, for example, provide sufficiently detoxified water for raising fish or watering livestock.

Anyway, just some ideas that come up in day-to-day activities here in the village. I wonder if we should test the crowd-funded-science-research waters. What do you think? Anyone want to team up on this project?


As usual, you can find me on Facebook, and please “Like” Aqueous Solutions!


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References

[1] At What Price? Gold Mining In Kachin State, Burma. Images Asia & Pan Kachin Development Society, November 2004. [http://www.ibiblio.org/obl/docs/gold%20pdf1.pdf]

Vrieze P, Naing Zaw H. In Tenasserim hills, rise in mining threatens communities. The Irrawaddy, Wednesday, February 5, 2014. [http://www.irrawaddy.org/feature/tenasserim-hills-rise-mining-threatens-communities.html]

[2] Blum D. The Poisoner’s Handbook: Murder and the Birth of Forensic Medicine in Jazz Age New York. Penguin, pubs. 2011. The book has also been made into a PBS film: http://www.pbs.org/wgbh/americanexperience/films/poisoners/

[3] Akcil A., Mudder T. Microbial destruction of cyanide wastes in gold mining: process review. Biotechnology Letters 25: 445–450, 2003.

[4] ATSDR Toxicological Profile for Cyanide. [http://www.atsdr.cdc.gov/toxprofiles/tp8-c6.pdf]

[5] Gould WD, King M, Mohapatra BR, Cameron RA, Kapoor A, Koren DW. A critical review on destruction of thiocyanate in mining effluents. Minerals Engineering 34 (2012) 38–47.

[6] Dictor MC, Battaglia-Brunet F, Morin D, Bories A, Clarens M. Biological treatment of gold ore cyanidation wastewater in fixed bed reactors. Environmental Pollution, Vol. 97, No. 3, pp.287-294.

[7] Mohan D, Sarswat A, Ok YS, Pittman CU. 2014. Organic and Inorganic Contaminants Removal from Water with Biochar, a Re- newable, Low Cost and Sustainable Adsorbent- a Critical Review. Bioresource Technology (in press).


Thursday, March 20, 2014

(Bio-) Chemists Without Borders: Help Aqueous Solutions Hack Field E. coli Testing!

Biochemists and microbiologists: Aqueous Solutions has a mission for you.

By Josh Kearns
  
I recently visited two village training centers deep in the wilds of Tenasserim district (Thailand-Burma border region), where colleagues and I conducted follow-up inspections on water treatment systems installed by local trainees during recent months. (Check out our Facebook page for photos from the trip.)

On this trip and the other routine visits we make to project sites, in addition to troubleshooting, refurbishment, and data collection to supplement our research objectives, we perform microbiological testing to verify drinking water safety. For this task we have been using 3M Petrifilms, which indicate total coliforms as well as E.coli in a 1 mL water sample.


Local trainees conducting E.coli testing.

Over the years, Petrifilms have proved indispensible for validating our treatment system designs, as they are the most practical and economical (about US$2 per test) test for microbiological water quality that we have yet come across.


Naw Gay Pho giving instruction on interpretation of the microbial tests.

Their main drawback, though, is the 1 mL sample volume. The international World Health Organization (WHO) standard for water quality includes the criteria for E.coli of less than one colony-forming unit (CFU) per 100 mL. With a 1 mL sample volume, this standard is thus two orders of magnitude below the detection level of the Petrifilm test.

However, a new field-oriented commercial E.coli test kit was recently brought to our attention. This method makes use of a 100 mL sample volume, and a simplified approach to most-probable-number (MPN) analysis – allowing for better precision and achieving a lower, WHO-approved detection level.

Unfortunately, at over US$10 per test, this particular E.coli testing system is priced well out of the range of affordability for small, grassroots NGOs like Aqueous Solutions and our community based partners. Furthermore, these test kits are rather bulky, containing a lot of single-use plastic ware. This would make it cumbersome, if not impossible, for example, to hike distances in remote, rugged terrain with enough supplies for testing several water sources and treatment systems. Moreover, the single-use plastic ware presents a safe and environmentally responsible disposal challenge. (Where we work, it’s not a matter of phoning up the local EH&S to come by and properly dispose of our bio-waste!)

We have, however, devised a “hack,” that will allow us to use the basis of this commercial method but at greatly reduced cost, and with less bulky and reusable equipment.

The hack is nearly complete, but we lack one key ingredient: 5-Bromo-4-chloro-3-indolyl β-D-glucuronide, also known as “X-Gluc.” X-Gluc is a chromogenic indicator that produces a blue color in the presence of E.coli.

So, Biochemists and Microbiologists Without Borders, your mission, should you choose to accept it, is to help Aqueous Solutions identify a convenient and economical source of X-Gluc.

The ideal form would be a tablet pre-dosed for 100 mL sample volume. Sigma-Aldrich sells tablets, but they are quite expensive. We contacted the company selling the MPN test kits described above about purchasing their E.coli media pellets but they will not sell them separately from the test kits. And since the media pellets are proprietary, they will not provide any information about how to acquire them directly or derive our own.

(As an editorial aside, this is an example of how intellectual property can inhibit rather than promote innovation, as is commonly claimed. Our goal is not to undermine the market for this company’s product, but to build on the extant research and development to adapt the system for other scenarios where it is currently infeasible – and therefore there currently is no market. Making knowledge artificially scarce by keeping the E.coli media formulation proprietary is obviously unhelpful from the perspective of the many communities who could benefit from water testing…)

Anyway, that’s our pitch. Any leads for how we can secure a supply of X-Gluc in a cost effective manner would be much appreciated! We are really excited about this hack and the potential it represents to increase the sensitivity and robustness of our water system validation field protocol!

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As per usual, please feel free to follow me on Facebook (https://www.facebook.com/joshua.kearns.399), and “Like” Aqueous Solutions (https://www.facebook.com/AqueousSolutions)!



Thursday, March 13, 2014

A Chemist’s Critique of Economics and “Sustainable Development”

Part I: Contemplation of the Energy Return on Investment (EROI)

Author’s note        This post is a bit longer (and headier) than previous posts, but herein I open a very complex and somewhat controversial constellation of subjects, and attempt to treat matters in a cross-disciplinary manner and at the root-level.

My intention in blogging for Chemists Without Borders is, in addition to producing journalistic descriptions of field projects and laboratory research geared to the development of appropriate water and sanitation technologies, from time-to-time to develop in-depth discussion of pertinent “big-picture” themes in economics and sustainability. I invite you to participate in the discussion through the “Comments” section – your feedback will likely shape future posts on these complex topics.

That a Chemist would inveigh against contemporary prevailing economic orthodoxies is perhaps a rarity but not without precedent.  Frederick Soddy won the 1921 Nobel Prize in Chemistry for his work (with Ernest Rutherford) on radioactive decay, but spent much of the rest of his career developing critique and prescriptions for economics rooted in physics. He called for radical shifts in our concepts and policies pertaining to money and finance, including, for example, the abolition of fractional reserve banking. For this, according to one reviewer of Soddy’s legacy writing recently in the NY Times op-ed section, he was “roundly dismissed as a crank.”

I’m well aware of the danger of also being labeled a crank, at least in the short term. But as the saying goes, “Nature bats last.” Moreover, the ideas of Mr. Soddy and his intellectual heirs in the emergent paradigm of Ecological Economics go along way to explain the abysmal failure of most establishment efforts in “sustainable development” over recent decades. These matters are deeply relevant to scientists such as “Chemists Without Borders” aspiring to impact the humanitarian development sector in a durable and beneficial manner.

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The word sustainability is flung around an awful lot these days, not least in the eponymous sector of sustainable community development. Unfortunately this most often happens with an astonishing lack of comprehension of basic foundational concepts. As “Chemists Without Borders,” we might hope to offer some prescriptive illumination on the subject.

A major hindrance to authentic sustainable development arises from the gaping disconnect between economics and the natural sciences. As an undergraduate Chemistry major, I was introduced to the First and Second Laws of Thermodynamics – in lay terms, (1) matter and energy are conserved, neither created nor destroyed but rather altered in form, and (2), there’s no such thing as a free lunch. Accordingly, it never fails to send me into a state of sputtering apoplexy when I hear economists, business people, political leaders, and development wonks stumping for this-or-that program designed to “promote and ensure sustainable growth.”

It ought to be obvious to everyone that pursing infinite growth on a finite planet is a futile (and destructive) absurdity. But most professionals, even those working explicitly in the “sustainable development” sector don’t seem to get it. (Trust me – I have been to their conferences, and no, they don’t get it.)

The problem extends right up to the highest levels of thought-leadership. To wit, financier Michael Metcalfe’s recent vacuous and smarmy TED talk suggesting the solution to global poverty is just to print more money. Jeez – why didn’t we think of that decades ago and avoid the whole problem of poverty in the first place?

Concerns about the rampant inflation such an approach would trigger notwithstanding (Metcalfe lamely dodges this point in his talk), it’s obvious that the self-proclaimed “financial whiz, economist and macro strategist” has no grasp on the fact that debt-based money represents a future claim on real wealth, that the ultimate source of all real wealth is Nature (i.e. the biosphere), and that under a highly leveraged fractional reserve system the aggregate of such claims may far exceed the capacity of physical resources to pay them back.

I harshly pick on Metcalfe as a rhetorical foil to make the point that we Chemists (With or Without Borders), along with our other natural science colleagues, have a mission to “connect-the-dots” that will bring economic and development agendas back into conformation with bio-physical reality.

EROI: Energy Return on Investment

To do this, our conceptual toolkit should include an in-depth look at EROI: “Energy Return on Investment.” EROI is net energy – the amount of energy left over once the energy costs of extraction are subtracted. Professor David Murphy of Northern Illinois University has recently published an excellent review of EROI with sobering implications for the future of economic growth.

We in the developed world have gotten used to continual economic growth as "normal" over several generations' time since the advent of fossil fuels, oil being of prime significance. In the past, we have always being able to expand our access to cheap, accessible high-EROI oil, and this has enabled economic growth and vast increase in societal and infrastructure complexity. In the initial heyday of US oil drilling in the early 20th Century, for example, the EROI was 100:1 or more (Hall and Day, 2009; Heinberg, 2011). This means that for every barrel of oil expended in exploration, drilling and extraction, we got 99+ barrels in return – an energy windfall unprecedented in the evolutionary history of the planet.

Given that the exponential increase in global economic output over the past 200 years is highly correlated with the same exponential increase in energy consumption (Murphy, 2014; see also below), the exhaustion of cheap high-EROI oil can be expected to cause economic growth to stall and reverse into contraction. This, in turn, can be expected to precipitate rapid civilizational decomplexification along with severe social and economic dislocation, since the energy surpluses used to build and maintain societal infrastructure at a previously high EROI erode rapidly and in a nonlinear manner.


Over the past decade, we've run out of cheap, easily accessible, high quality oil, and have begun to exploit more dispersed, environmentally risky, geo-politically contentious, low quality, and therefore more expensive, low-EROI resources such as fracked shale oil, tar sands, and super deepwater offshore deposits. Murphy summarizes that  “the average EROI for US oil production has declined from roughly 20 in the early 1970s to 11 today, while the global average EROI was roughly 30 in 2000 and has declined to roughly 17 today.” He indicates that the EROIs of oil production from ultra-deep-water areas, biofuels, and tar sands/oil shale are “less than 10,” “between 1 and 3,” and “roughly 1.5,” respectively.

For professionals in all fields concerned with true sustainable development, then, the ineluctable but deeply troubling questions is,

What is the minimum EROI required to run a highly globalized and integrated, sub-/urbanized, industrialized, hyper-complex society, and where are we now with respect to that minimum?

Furthermore, this question must be asked with the cognizance that, as Murphy points out, (1) the exponential relation between gross and net energy flows (the so-called ‘net energy cliff’, see below) comprises a critical point in the relation between EROI and price at an EROI of about 10; (2) the relationship between EROI and profitability becomes highly nonlinear as the EROI declines below 10; and (3) the minimum oil price needed to increase global oil supply in the near term is comparable to that which has triggered economic recessions in the past.


High oil prices reliably send the economy into a recession, because energy is the “master resource” that effects the production, and prices, of all other goods and services in the economy. Economic recession destroys demand, lowering oil prices; but if oil prices drop, then it is no longer economical for energy companies to exploit expensive low EROI resources. These upper and lower oil price bounds have characterized the bumpy plateau of oil production that we have been on since 2005, and go along way explaining our protracted economic non-recovery from the financial crash of 2008. Some analysts think that this indicates we’ve hit peak oil, and also that it signals the end of the era of economic growth (e.g. Heinberg, 2011) – that we are not in a "recession" per se, because "recession" implies a defined trough ending with an uptrend back to "normal," but are experiencing the first symptoms of economic stall and contraction.

The problem within the so-called “sustainable development” sector is that we talk incessantly about sustainability when we should be talking about un-sustainability. Economic growth is unsustainable, by definition, since it implies increasing demands for energy, resources, and waste assimilation capacity. Moreover, at this point in time the proliferation of “illth” (economic “bads”) has outstripped the production of wealth (economic “goods”), and so further growth should rightly be termed uneconomic (Daly, 2005). Substitution, technological innovation, and gains in efficiency can help, but not beyond the limits specified by the laws of thermodynamics. (Many scientists and engineers who should know better frequently forget this point.) Moreover, efficiency gains often backfire as increased consumption outstrips them (the so-called Jevons Paradox, or rebound effect). Technological innovation routinely creates more problems than it solves through unintended consequences and diminishing returns (e.g., see Heusemann and Heusemann, 2011). And as ecological economists have demonstrated, human capital is complimentary to natural capital, not a substitute for it as assumed by mainstream economists (Daly and Farley, 2004). This limits the extent to which resource substitution is effective or possible.

These are all concepts that Chemists and other natural scientists should have no problem grasping, because they are rooted the same laws (conservation of matter and energy, thermodynamics and entropy, etc.) that form the basis of our research and teaching. Our task is therefore to help society use these science-based methods for setting targets for authentically sustainable development.

Delving into more specifics and variations for how we can accomplish this task will be taken up in future blogs.

As per usual, please feel free to follow me on Facebook (https://www.facebook.com/joshua.kearns.399), and “Like” Aqueous Solutions (https://www.facebook.com/AqueousSolutions)!


References and Further Reading

Berry W. Faustian Economics. Harpers Magazine, May 2008.

Berry W. Inverting the Economic Order. The Progressive, Vol. 73, September 2009.

Daly H.  Economics in a Full World. Scientific American, September 2005.

Daly H., Farley J. Ecological Economics: Principles and Applications. 2004. Island Press, pubs.

Georgescu-Rogen N. The Entropy Law and the Economic Process. 1971. Harvard Press, pubs.

Hall C., Day J. Revisiting the limits to growth after peak oil. American Scientist Vol. 97, May-June 2009.

Heinberg R. The End of Growth: Adapting to Our New Economic Reality. 2011. New Society, pubs.

Heusemann M., Heuseman J. Techno-Fix: Why Technology Won't Save Us Or the Environment. 2011. New Society, pubs. [newtechnologyandsociety.org]

Murphy D. The implications of the declining energy return on investment of oil production. Phil. Trans. R. Soc. A January 13, 2014.

Sorrel S. Energy, Economic Growth and Environmental Sustainability: Five Propositions, Sustainability 2010, 2(6), 1784-1809.

Zencey E. Mr. Soddy’s Ecological Economy. New York Times, Opinion-Editorial section, April 11, 2009.





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