Questions about energy generation from coal

[hagopbul]

TL;DR Summary

reduction of coal consumption for energy generation

Hello :

i was watching the news , and it was all about how Europe will start the coal factories again for energy generation

had a question related to reduction of coal consumption for energy generation

1 ) could we use coal fine particles instead of chunks of coal that will burn more efficiently and reduce the amount that is used for the process and in the same time reduce the amount of CO2 generated of the system

2) could we use the fine particles above mentioned with mixture of atmosphere that have more oxygen percentage in it , which also will result in less coal been burned and less CO2 been released

3) coal fine particles range from micrometer to sub micrometer

4) could we treat the coal particles for reduction of CO gase releases

Best Regards
Hagop

 

[Baluncore]

1 ) could we use coal fine particles instead of chunks of coal that will burn more efficiently and reduce the amount that is used for the process and in the same time reduce the amount of CO2 generated of the system

The coal is pulverised now.
https://en.wikipedia.org/wiki/Coal-fired_power_station#Fuel_processing
CO2 is generated in proportion to the energy generated. Less CO2 is less energy.

2) could we use the fine particles above mentioned with mixture of atmosphere that have more oxygen percentage in it , ...

There is no advantage in using concentrated oxygen.
Again, Less CO2 is less energy.

4) could we treat the coal particles for reduction of CO gase releases

That is best done by making sure there is sufficient air to burn the CO to CO2.

 

[anorlunda]

Good questions.

Power plants burn pulverized coal, which is like a fine dust. The energy to run the pulverizers must be subtracted from the electric power produced.

Power plants also carefully control the ratio of air to fuel to assure complete combustion with no excess air. The combustion would be more efficient with more oxygen, but the energy needed to produce the oxygen from air must be subtracted from the electric power made.

Others have noted here on PF that an alternative to burning more coal in Germany was to add a new major north-south transmission line. The German people rejected that idea.

Many times, choices have unforeseen consequences.

 

[Baluncore]

Others have noted here on PF that an alternative to burning more coal in Germany was to add a new major north-south transmission line. The German people rejected that idea.

March 2021 New underground transmission line.
https://www.cleanenergywire.org/new...irms-route-corridor-north-south-power-highway

 

[hagopbul]

couldnt we surface treatment of the coal particles during pulverization to increase the speed of oxygen reaction with the surface of the coal particles

 

[russ_watters]

couldnt we surface treatment of the coal particles during pulverization to increase the speed of oxygen reaction with the surface of the coal particles

The speed of the reaction doesn't change the energy balance, but as said pulverized does ensure good mixing with air for uniform, complete combustion.

 

[anorlunda]

couldnt we surface treatment of the coal particles during pulverization to increase the speed of oxygen reaction with the surface of the coal particles

What would you hope to accomplish? For maximum efficiency you want

• Complete combustion
• Highest temperature
• Lowest clumping of waste products

Some furnaces create a cyclone circulation. That increases residence time in the furnace and increases fuel to air contact. Faster burning might improve that, but incremental changes only, not a major change.

There is some conflict between combustion efficiency and production of pollutants, especially nitrous oxides. Any change in the combustion parameters has the potential of increasing pollutants, so it would have to be carefully evaluated and monitored.

The world has more than 200 years experience in burning coal, so new ideas that have not been considered before are really hard to find.

If people anyplace use electricity partially generated by coal, the best way to improve the situation is to consume less energy. Conserve.

 

[hagopbul]

higher reaction speed equal higher heat release if i am not mistaken , isn't it ?

 

[anorlunda]

higher reaction speed equal higher heat release if i am not mistaken , isn't it ?

No. Higher heat release per second but not higher total release when reaction is exhausted.

 

[256bits]

couldnt we surface treatment of the coal particles during pulverization to increase the speed of oxygen reaction with the surface of the coal particles

You could use gasification to get some benefit, but it is expensive.
https://en.wikipedia.org/wiki/Integrated_gasification_combined_cycle

 

[sophiecentaur]

the best way to improve the situation is to consume less energy. Conserve.

As ever.
But that's not an attractive solution and would involve a significant change of lifestyle for 'First World' countries. ("Why should we?")

 

[anorlunda]

As ever.
But that's not an attractive solution and would involve a significant change of lifestyle for 'First World' countries. ("Why should we?")

It is an inconvenient truth.

(Al Gore got a Nobel Prize for saying that. Do I get one too?)

 

[russ_watters]

The best way to improve the situation is to consume less energy. Conserve.

But that's not an attractive solution and would involve a significant change of lifestyle for 'First World' countries. ("Why should we?")

It is an inconvenient truth.

I disagree with both. The west is already reducing energy use per capita while continuing to increase standard of living. But even then it isn't necessarily required.

The problem is the developing world, which has no other option but to massively increase energy use in order to increase standard of living. So in order to do it without carbon...they have to do it with carbon free sources of power.

Of course, so can we if we ever decide we feel like it.

 

[hutchphd]

(Al Gore got a Nobel Prize for saying that. Do I get one too?)

Sorry no. But I will give you a gold star instead Congratulations for work well done!

 

[Vanadium 50]

Many times, choices have unforeseen consequences.

Or forseen ones.

 

[Baluncore]

couldnt we surface treatment of the coal particles during pulverization to increase the speed of oxygen reaction with the surface of the coal particles

Pulverisation greatly increases the surface area of the fuel, which leads to a faster reaction with the oxygen in the air that is used to transport the coal dust into the furnace. The surface area of the dust is so great that a surface treatment would require a similar weight of treatment material be applied to treat the fuel dust. Have you worked out the surface area of 1 kg of coal, pulverised to dust of different sizes?

There are fuel additives that can be blended into the air+fuel flow which cleanse the flue gasses. But those additives do not coat the fuel particles, they react later with the combustion products to reduce air pollution.

higher reaction speed equal higher heat release if i am not mistaken , isn't it ?

The combustion of fuel dust in the air is so fast that the dust has no time to settle before it becomes ash. Any coating would slow the reaction, or cost more energy than it generates.

 

[Frabjous]

Pulverisation greatly increases the surface area of the fuel, which leads to a faster reaction with the oxygen in the air that is used to transport the coal dust into the furnace. The surface area of the dust is so great that a surface treatment would require a similar weight of treatment material be applied to treat the fuel dust. Have you worked out the surface area of 1 kg of coal, pulverised to dust of different sizes?

There are fuel additives that can be blended into the air+fuel flow which cleanse the flue gasses. But those additives do not coat the fuel particles, they react later with the combustion products to reduce air pollution.The combustion of fuel dust in the air is so fast that the dust has no time to settle before it becomes ash. Any coating would slow the reaction, or cost more energy than it generates.

This sounds similar to the dust explosion hazard in coal mines. Why isn’t this a concern in power plants?

 

[Baluncore]

This sounds similar to the dust explosion hazard in coal mines. Why isn’t this a concern in power plants?

Because the rate of combustion is regulated by the rate of fuel and air delivery. Combustion of the mixture is initiated by the heat of the furnace, then more air is added.

 

[sophiecentaur]

The west is already reducing energy use per capita while continuing to increase standard of living.

Why should it be necessary to be increasing the 'standard of living' beyond an 'adequate' level? The problem is that there is an expectation that, if less fortunate people's lives are improved then the lives of the already fortunate should also improve - and more than just pro-rata. If the West is doing better then that's good but there are many sneaky ways of making it look that way when they may not, in fact, be doing so.

Unfortunately, success is always interpreted in terms of 'growth'. Growth is possible by increasing trade and business within a nation (good old Keynsian arguments) but the numbers often rely on exploitation of less developed countries in the same system of a hundred years and more ago.

 

[Rive]

March 2021 New underground transmission line.

The first predictions of the problem what made those lines necessary dates back around 2008

The installation of PSTs to mitigate the troubles originating from the missing line and keep the troubles within Germany took just two years, 2016 to 2018
The separation of the affected monolitic bidding zone (DE-AT) which was needed to keep the troubles at bay happened at the end of 2018 (what a marvelous coincidence).

And finally, they managed to draw the route for that line.

I'm impressed.

 

[anorlunda]

The installation of PSTs to mitigate the troubles

What is a PST?

 

[Baluncore]

PST = Phase Shift Transformer.
But I think SuedLink is an underground 525 kV DC link.

 

[Rive]

But I think SuedLink is an underground 525 kV DC link.

Sorry for not being clear. This was ~ the background/trigger of the mentioned PST installations. The affected stations were (all) the border crossings between PL-DE and CZ-DE (check the map in the article!).

So the PSTs were to 'cage' the unwanted flows within Germany - and once the possibility of unaccounted flows gone miraculously Germany could find the money and will to start their own work towards a solution.

By the way all the border crossings on the western side are DC links. Those has inherent means to control the power flow. It's logical to have the new underground north-south line as a DC link too.

 

[anorlunda]

Sorry for not being clear. This was ~ the background/trigger of the mentioned PST installations. The affected stations were (all) the border crossings between PL-DE and CZ-DE (check the map in the article!).

Wow. I just read that article. It sounds like WW3 on the Euro grid. But to be fair, an analogous problem arose between the US and Canada with power flowing "the wrong way" in loops around Lake Ontario and Lake Erie. But that problem was due to an unforeseen loophole in negotiated rules. The loophole was fixed without parties getting angry at each other.

When different parties share a power grid, all the rules must be rational, fair, and above all apolitical. Apolitical is achieved by excluding all governments from the negotiations.

 

[Rive]

It sounds like WW3 on the Euro grid.

Since 'green' became a tool for political warfare here, it's quite an adequate comparison

 

[anorlunda]

Since 'green' became a tool for political warfare here, it's quite an adequate comparison

From today's news; partially analogous.

https://www.bbc.com/news/world-us-canada-62072844
New England Clean Energy Connect (NECEC) was supposed to be an industry-leading project, transporting 1,200 megawatts of Canadian hydropower to Massachusetts across 145 miles (233 km) of transmission line, and eliminating over three million metric tonnes of carbon emissions every year.
The $1bn (£840m) project, funded by utility company Hydro-Quebec and Central Maine Power (CMP), which is owned by the Spanish energy giant Avangrid, received final approvals, including a Presidential Permit from the US Department of Energy. Construction began in January 2021.
Now, the hydropower project could be dead in the water, after a majority Mainers voted to cancel it last November.

Also very political are "energy independence" politics that treat Canada as a separate country than the USA. Northeast US states much prefer hydro power from Canada over wind power from the US Midwest states.

Also very political are the differences between the Canadian provinces Ontario versus Quebec as power partners.

Also very political

https://www.sfgate.com/bayarea/article/climate-vigilantes-deflate-suv-tires-17293468.php

Vigilante climate activist group deflates Bay Area SUV tires overnight​