What have you done today to lower your impact?

We are washing away the foundations of our existence on every front. It is high time we move from crashing about on the planet like a bull in china shop and find a way to go forward with intent. We must find systems of living based on sustainability. The systems and tools exist, it is up to each of us to adopt them.

Blog Archive

Saturday, 15 November 2008

Green Chemistry and Engineering and green coal

Check out this excellent article over on celsias about the "other" waste products coal combustion is poisoning us with.
Green Coal? | Use Celsias.com - reduce global °Celsius

Of particular interest are the 12 principles of "green chemistry" and "green engineering" posted below for you to review before reading the article by Peter Montague. Here is his introduction,

"As we search for solutions to global warming and toxic contamination, we can compare technologies, intending to select the least harmful. In recent years, scientists have developed two sets of criteria that we can use to judge the "greenness" of competing technologies. The first is called "The 12 principles of green engineering " and the second is "The 12 principles of green chemistry ."

Both sets of principles were developed by teams of technical experts and published in peer-reviewed journals. They are now widely understood and endorsed. Most importantly, they offer ordinary people, as well as experts, a way to decide which technologies are worth supporting and which ones should be phased out or never developed at all."

The 12 Principles of Green Engineering

[First published in Paul T. Anastas and J.B. Zimmerman, "Design through the Twelve Principles of Green Engineering", Environmental Science & Technology Vol. 37, No. 5 (March 1, 2003), pgs. 95A-101A .]

Principle 1: Designers need to strive to ensure that all material and energy inputs and outputs are as inherently nonhazardous as possible.

Principle 2: It is better to prevent waste than to treat or clean up waste after it is formed.

Principle 3: Separation and purification operations should be designed to minimize energy consumption and materials use.

Principle 4: Products, processes, and systems should be designed tomaximize mass, energy, space, and time efficiency.

Principle 5: Products, processes, and systems should be "output pulled" rather than "input pushed" through the use of energy and materials.

Principle 6: Embedded entropy and complexity must be viewed as an investment when making design choices on recycle, reuse, or beneficial disposition.

Principle 7: Targeted durability, not immortality, should be a design goal.

Principle 8: Design for unnecessary capacity or capability (e.g., "one size fits all") solutions should be considered a design flaw.

Principle 9: Material diversity in multicomponent products should be minimized to promote disassembly and value retention.

Principle 10: Design of products, processes, and systems must include integration and interconnectivity with available energy and materials flows.

Principle 11: Products, processes, and systems should be designed for performance in a commercial "afterlife".

Principle 12: Material and energy inputs should be renewable rather than depleting.


The 12 Principles of Green Chemistry

[First published in Martyn Poliakoff, J. Michael Fitzpatrick, Trevor R. Farren, and Paul T. Anastas, "Green Chemistry: Science and Politics of Change," Science Vol. 297 (August 2, 2002), pgs. 807-810 .]

1. It is better to prevent waste than to treat or clean up waste after it is formed.

2. Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product.

3. Wherever practicable, synthetic methodologies should be designed to use and generate substances that possess little or no toxicity to human health and the environment.

4. Chemical products should be designed to preserve efficacy of function while reducing toxicity.

5. The use of auxiliary substances (e.g., solvents, separation agents, and so forth) should be made unnecessary wherever possible and innocuous when used.

6. Energy requirements should be recognized for their environmental and economic impacts and should be minimized. Synthetic methods should be conducted at ambient temperature and pressure.

7. A raw material or feedstock should be renewable rather than depleting wherever technically and economically practicable.

8. Unnecessary derivatization (blocking group, protection/deprotection, temporary modification of physical/chemical processes) should be avoided whenever possible.

9. Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.

10. Chemical products should be designed so that at the end of their function they do not persist in the environment and break down into innocuous degradation products.

11. Analytical methodologies need to be developed further to allow for real-time in-process monitoring and control before the formation of hazardous substances.

12. Substances and the form of a substance used in a chemical process should be chosen so as to minimize the potential for chemical accidents, including releases, explosions, and fires.


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