Let’s come clean on “dirty” coalViv Forbes | August 26, 2012
Viv Forbes sent me this a few weeks ago and it got buried under my to-do pile. I don’t know how NZ coal compares with the Australian version he mentions, but there are several coal specialists who visit here – perhaps one of them might enlighten us. – Richard Treadgold
We are winning the war on man-made global warming.
But about half of the population still think that the carbon tax will do some good. Why? Because they think it is all about cleaning up “dirty coal”.
The seeds of public concern were sewn with Penny Wong’s Machiavellian linking of “carbon” and “pollution”. She was assisted by the gross stupidity of the coal industry leadership in promoting nonsense like carbon sequestration as a “clean coal” option. The public naturally assumed “if they need to spend billions to produce clean coal, obviously we are now using dirty coal. This generation of coal industry leaders is more culpable than the greens, because they should have known better – they have betrayed their shareholders, their employees and the nation.
The whole “dirty coal” programme was assisted by the continual portrayal by alarmist media and government propagandists of power station cooling towers belching “pollution”. As carbon dioxide is an invisible gas, this is clearly a lie. What is seen are clouds of water vapour with no more pollution potential than wispy white cumulus clouds or boiling dark nimbus thunder-heads. Have a gander at this photo.
When looking for a suitable photo of the Bayswater Power Station in New South Wales I couldn’t help noticing how clean it looks. In every photo taken in good weather, there’s no sign of smoke coming out of the plant. Some “eco” sites use images taken facing the sun, which shows the steam in shadow and makes it look a bit dirty. Although it’s not dirty. As you can see, modern coal power stations are very clean.
The climax of all this was a letter published in the Queensland Times of Ipswich, a town founded on coal mining, describing carbon dioxide as “one of many lethal pollutants released by coal combustion.”
What’s the truth?
The facts on coal combustion
When we burn any carbon fuel such as coal, oil, wood, gas, grass, candle sticks, cardboard or cow manure, it produces several gases. Burning a typical Australian thermal coal in air would produce mainly nitrogen (68%), carbon dioxide (21%), water vapour (7%), oxygen (1%), argon (1%) and ash (2%).
So 98% by weight of coal combustion products (the first five) are natural gases merely being recycled to the atmosphere from whence they came. None are toxic. All are invisible except for water vapour.
To describe carbon dioxide as a “lethal air pollutant” is an irresponsible lie – it is surprising to see such rubbish in print. Carbon dioxide is the most important and essential atmospheric plant food, without which there would be no plants, no herbivores (which live on plants), and no carnivores (which live on herbivores).
Our coal is simply another form of trees and plants that grew in Australian soils in a previous era. Ash is unburnt mineral matter that comes naturally from the soil and should go back there. Almost all of the ash is now captured in modern coal-fired power stations, but cannot be captured in bush fires, barbeques, wood stoves, cow manure cookers and open air cremations.
No more dangerous than burnt toast
Soot is a product of incomplete combustion and is not produced in modern, well-designed power stations. It is no more dangerous than burnt toast.
It is true that some coals can produce some SOX (oxides of sulphur) and NOX (oxides of nitrogen) but these are also caught in modern filters and cleaners. Only small traces enter the air. They could be annoying, and would be dangerous if concentrated in city air, but EVERY normal component of coal is an essential plant nutrient, and far from being invariably toxic, is often in short supply in the broader environment. Anyone who raises crops or animals often needs to supplement soils, pastures or animal feeds with nitrogen, sulphur, phosphorus, calcium, magnesium, copper, zinc and selenium, to name a few.
The few coal combustion products that are genuinely toxic, such as mercury, occur rarely and in tiny quantities. If present, special filters are used to ensure they are not released. Australian coals are generally very low in mercury, indeed lower than in the average earth environment. Naturally occurring rocks containing mercury (as found at Cinnabar in Queensland), dental amalgam and the new “green” fluorescent light bulbs represent a far greater mercury danger.
Compared with Earth’s long history, today’s level of atmospheric carbon dioxide is very low and the green world will benefit greatly from any additional carbon dioxide we add to the atmosphere. That is why nurserymen add carbon dioxide to their greenhouses.
Related posts at Carbon Sense
Here is a detailed report on coal combustion products.