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Monday, June 26, 2017

Clean Coal, (and other bed time fairy tales)


In recent weeks, if you live in America, you’ve heard a ton of how the coal industry has been oppressed under the Obama administration. You have heard that President (excuse me I just threw up a little) Trump is bringing back coal.  Putting them miners back to working their ass off, etc.  Well actually his tweet said minors, but whatever, I’m about 50% sure he means miners. 

In this post, I’m not going to get into the actual numbers of mining jobs, or how much coal is produced.  Nope, I’m going to talk about what “Clean Coal” is.  Sit back and relax as we toddle down the road of clean coal half truths and alternate facts!

First things first, what is Clean Coal?  Well, according to the Department of Energy, who I must point out is led by none other than ‘ol pointy boots himself Rick Perry, clean coal is a series of processes and technologies that make coal less harmful, help it produce more power, and other really nice sounding things.  The big-ticket item in clean coal is carbon dioxide capture or sequestration.   

Basically, burn the hell out of it, and pump the CO2 underground and hope for the best.  At no point in the process is the coal any less hazardous than it always was.  Clean coal should really be called “cleaner coal smoke” because that’s where whatever improvements in the process are can be found.  The exhausted gases if the system works as describe will be lower in CO2, and sulfur.  There could be some reduction in the heavy metals leaving the stack, but the majority of that is not from clean coal tech, but rather the stack scrubbers operating at higher levels of efficiency, or the scrubbing elements of the stack being improved in general.

While speaking of higher efficiency, clean coal tech reportedly is being used to make the process of power generation with coal more efficient.  Pushing the process to higher levels of efficiency is awesome, right? Well, there’s one problem with that statement, combustion has a maximum efficiency of that relates to the amount of oxygen present in the process.  That is the ONLY factor that can improve the process, assuming that the coal you have is the same type from one test to the other.  Now for the record, there are five primary types of coal they are peat, lignite, subbituminous, bituminous and anthracite.  In my geology studies, we didn’t count peat, since it is the parent material for coal, and not readily used in the coal energy production model for power generation.  In general, however they are harder and thus more energy packed per unit in the above respective order.  The hardness is related to how the coal formation was deposited, the amount of pressure and heat it underwent and the amount of plant material remaining in a sample. 

Anyway, so let’s say you have a pound of high quality West Virginia anthracite coal and you have a fire roaring along, then throw that coal in there.  In normal oxygen levels, that one pound of anthracite will produce 12,700 BTU’s, which are British Thermal Units.  Now, let’s say I start blowing air into the fire with a fan or some sort of apparatus.  The fire will get hotter because there is more air, i.e. we are in excess, and the combustion becomes more efficient.  At the end of the day this is great, but there is a limit on the efficiency of combustion.  Under most models that I’ve seen, the limit on the best coal burning power plant translates to around 60% efficiency, while some of the worst are down into the range of 15%.  Older plants, by in large were less efficient than newer plants.  The efficiency is also effected by the coal type burning, but again, that difference is minor compared to how the reaction is managed.

Now the clean coal folks would have you believe that gasification and other processes improve efficiency and while that statement isn't wrong per say, it’s not telling the whole story.  The process overall can be improved by using gasification in so much as it can reduce levels of sulfur or in some cases CO2 in the gas product BEFORE its reacted.  The process doesn’t improve the burn because again that is limited by the amount of oxygen present in the reaction chamber.  There is a point also where you can feed no more oxygen into the chamber and not start reducing the heat output because it’s being lost to all that air blowing in.

Long story short, clean coal is a lot of smoke and mirrors.  The coal itself is just as dirty and dangerous as it always was.  The men and women mining it are getting just as sick from black lung and all sorts of other aliments from the work as they always were.  The danger is that under the guise of science, the truth of their plight and the truth of coal is being hidden.  The real dangers are being overlooked in favor of profit margins and frankly the deaths of the miners and the illness that plague the communities is simply blood on the hands of the government who allows the use to expand and the people making money off the effort. 

Those who would deceive you have gotten really good at making the tech sound “sciency” and cutting edge.  And to be complexly fair some of it is novel and does help clean up the exhausted product, but nothing and I do mean nothing, can make the coal coming out of the ground less dangerous. 

Remember, the fight for our environment is not a sprint, it’s a marathon.  We all need clean air, clean water and clean land to survive, and no amount of political rambling and certainly no amount of hot air from the GOP and Trump can change the biology of survival.  Keep resisting!

Below you will find links to various sources that discuss coal, clean coal and the economics of it all.  


Until next time ~





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