Written by Harold Armitage

 

 

The extraction and burning of fossil fuels causes massive pollution which cuts years off the lives of many people and reduces the quality of life through ill health. especially in urban environments.

As well as pollution of the air, we have pollution of agricultural land and hence water and everything we eat.

Extraction.

Extraction of fossil fuels causes massive disturbance to the landscape.
Millions of years ago, rainfall leached out substances toxic to us and washed them out to sea where they were buried by silt. They are toxic to us because we have never been exposed to them as we evolved.

Extraction of fossil fuels by mining or drilling brings these toxic substances to the surface; they are not easily got rid of. The problem is especially bad in third world countries where often no effort is made to safely dispose of the various wastes. As fossil fuels (and other minerals) become depleted ever more extreme methods are needed to extract them.

The fuels themselves also contain these substances. The ones burned in an unrefined state are especially dangerous to health.

Coal.

Coal is burned in an unrefined state. As well as carbon, coal contains ash, up to 25%, also sulphur. There are various grades of coal used for different purposes, ranging from cement and steel production to burning in power stations. This results in the production of ash which contains many toxic elements/heavy metals ranging from radioactive materials to mercury, arsenic, cadmium and thorium.  Some coal ash was used in the manufacture of “clinker blocks” for building work. Some coal ash is as radio active as medium level nuclear waste. Fine ash particles can be carried into the atmosphere with combustion gases, (fly ash) so widely distributing these poisons.

In large industrial situations, combustion gases are “scrubbed” to largely remove contaminants but they still have to be disposed of once gathered in.  Sulphur dioxide in the combustion gases is removed by reacting it with limestone so making gypsum (plaster). However this now considered a bit iffy because of other contaminants.

However, there are still small obsolete users where scrubbing is not done so these poisons are released into the atmosphere. Burning coal domestically on an open fire is worst option of all, a large percentage of heat and unburned fuel is lost up the chimney.. Never let coal ash anywhere near your garden, many of the contaminants can be taken up by plants (especially arsenic). Arsenic laced cabbage is not unknown. Once in your soil, it will be there forever.

Oil

Oil too comes in many forms and come with most of the same poisons as coal. Unlike coal, oil is refined/distilled to produce many grades for different purpose,  At the end of the refining process, we are left with a black sticky substance known variously as “bunker oil”, “ heavy fuel oil” and “residual fuel oil”. This contains the various contaminants. Nevertheless it’s burned in power stations, ships and medium to large industrial heating systems.

The oil fractions we are most familiar with are the less viscous used to fuel motor vehicles and home heating. The nasties have largely been removed.  However, there is whole new set of more recently revealed problems.

Quenching

All our fuels are mixed with a carefully calculated amount of air plus a little extra to try to ensure that the fuel is as completely burned as possible. However if the burning air/fuel mix is cooled too much before combustion is complete, the process stops and unburned fuel escapes with the discharged combustion gases. This is called “quenching”. This takes the form of carbon particles (known as Particulate Matter, (PM) and can occur with all our fossil fuels.  Most of what we are now exposed to and the most dangerous comes from the internal combustion engine.
Pollution from the internal combustion engine (ICE)

In order to ensure the maximum amount of fuel is burned, it is reduced to as fine a spray of droplets as possible. In days of yore this was done using the carburettor, nowadays by fuel injection, with much smaller droplets hence more of the fuel is burned leading to higher efficiency.

It’s not possible to design an engine where all the fuel is burned. This revolves around the melting points of the metals used which have to be cooled to prevent damage. This means that the fuel-air mix adjacent to the metal is also cooled, the combustion process ceases (quenching) leading to PM being generated.  Every little speck of this is coated with a carcinogenic material. The PM is so small (especially from diesel engines) that when inhaled it penetrates to every part of our body, even our DNA is affected with an unknown effect on our descendants.

Less exotic but still serious, it causes all manner of lung complaints and mental problems. Children are especially at risk, it’s now thought that many of these previously unknown childhood diseases/mental problems are down to air pollution.
(This has been determined statistically by comparing the health of children in high pollution areas with those in rural environments.) Two stroke engines are very polluting due to the lubricating oil being mixed with the fuel, hence now banned.

Other pollutants produced are NOx, oxides of nitrogen produced due to the high temperatures of burning fuel and ozone (no health benefits from ozone in spite of the traditions.) These cause various lung problems, most notably asthma. All combustion gases are bad for you regardless of the source, one of the reasons for short lives of our ancestors before chimneys came into wide use. To partially overcome this, “cats” are fitted to the exhaust system of many cars. (Cats = catalytic converter). The precious metal (yes more mining)  in these devices enables combustion to take place at lower temperatures than normal so getting rid of unburned fuel (well some of it at least). Also the NOx can be reduced. Attempts have been made to filter out the PM with very limited success.

It’s not possible to design an IC engine with no pollution, attempts were made back in the 70s  to make engines using ceramic materials to reduce quenching. All failed due to lubrication problems and the ceramic materials being too weak.

Gas

Gas is the least polluting of our fossil fuels mainly because it can be mixed very thoroughly with the air needed for combustion so reducing PM. Also as it’s mostly hydrogen, the main constituent of the combustion gases is water. The water produced is very acidic and NOx also is produced.

Carbon monoxide

Another probable constituent of combustion gases is partially burned carbon, ie, the gas carbon monoxide, one of the deadlier gases to humans. If there is the slightest possibility of combustion gases getting into your living space you must have a carbon monoxide (CO) detector. Any fuel-burning appliance, burning any fuel, with a conventional chimney poses this risk.

Explosion.

All our fossil fuels can cause explosions but the most likely is gas. To have an explosion, there must be a gas leak, an accumulation of gas and an ignition source. In spite of every precaution, we still have regular gas explosions. These then are the problems with burning fossil fuels. Depletion, pollution/health hazard/explosion, and climate change. It will take many decades and £billions to set up any alternative and it has to be done and done right now,

Nuclear

So what about nuclear where there are no combustion gas emissions?  We were promised back in the 50s that electricity from nuclear power would be so cheap as to be not worth metering. (What happened to that promise? They were actually  more interested in producing nuclear bomb materials than electricity.)
Nuclear energy divides into two camps; fission, and finally on the horizon, fusion. The current technology is fission. Apart from the prospect of nuclear accident, the main problem is disposing of nuclear waste. No totally satisfactory method has yet been devised.  Nuclear waste has been stashed away by many governments, including the UK, at vast cost. Yet to come is the permanent solution which again will be costly. There are numerous pie-in-the-sky schemes and some abject failures.   Further complicating the issue is that finally (after fifty years of experiments and research), nuclear fusion seems to be a possibility, theoretically far safer and with much reduced nuclear waste. (I have seen a good explanation as to why electricity from nuclear fusion will never be viable.)

This of course leaves a quandary about what to do next. Electricity supplies have to be planned many decades in advance. The consequences of being wrong are financially disastrous. Also not considered at the time of construction, the problems of decommissioning obsolete nuclear power stations.

The French have long had “cheap” nuclear power. It’s only been cheap because almost no money has been put aside for the eventual de-commissioning of nuclear power stations. (Steel is weakened after years of exposure to radiation.) Rumours of impending bankruptcy abound, which would leave the French taxpayer to pick up the tab.

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