Mass. looks to forests for renewable energy source (wood-burning power plants)

http://www.bostonherald.com/business/general/view.bg?articleid=1191395&srvc=business&position=recent

rather than direct burn like most of the coal power plants do now. Depends on the link but anywhere from 50 to 60 percent less CO2 created from that one change alone. I haven't been able to get any traction here on trying to get any discussion on this at all. Oh I've been told this and I've been told that, all of it being bullshit coming from people who don't understand the gasifier. We could go a long ways towards cleaning up our air if we would convert our present coal burning power plants to a power plant utilizing a gasifier.

http://fossil.energy.gov/programs/powersystems/gasification/index.html

I don't think it's as easy as having UPS deliver your new gasifier to replace your old coal burner.

all the rest of the plant can be used other than the burn chamber they have now. The cooling towers can still be used the delivery and stock piling of the coal is already there, the steam turbine is already there and on and on. Compared to a new plant this would or should be a cinch to do.

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Are you saying it's more efficient somehow, so that you get more energy per ton of coal used? What links are you refering to?

The new power plants to be built in Germany will use this technology. They will replace older inefficient plants. We should be doing the same. It will make electric cars cleaner and more efficient.

Much less co2 and much more energy DM

http://www.clean-energy.us/facts/gasification.htm

About Gasification
Proven in the United States and around the world, gasification produces fuel, chemicals, fertilizer, and other products from coal.
Bookmarks


Gasification: The Logical Hydrocarbon Alternative
What is Gasification?
How does gasification differ from combustion?
What are the primary gasification technologies?
What is the history of gasification?
Where is gasification in use at present?
What is the future of gasification?
Why is gasification so important?
How serious is America's natural gas crisis?
Can syngas really replace natural gas in the industrial sector?
Under what conditions could such substitution occur?



Gasification: The Logical Hydrocarbon Alternative




Modern life depends upon energy and with each passing day it becomes more evident that clean, climate-friendly, and affordable energy technologies must be deployed as rapidly as possible. To that end, the United States and other nations are striving to make wind, solar, geothermal, hydrogen, and other “green” technologies a larger part of their overall energy mix.

However, for technical and economic reasons, it will be many decades before these resources can meet more than a fraction of the world’s energy demand. In the meantime, developed countries such as the United States and developing nations such as China and India will continue to rely upon hydrocarbons (natural gas, petroleum, and coal) for electricity generation and transportation fuel. So, it is fair to ask: What are our hydrocarbon options?

Natural Gas. This clean-burning hydrocarbon is in great demand both as a fuel to heat homes and run powerplants and as a raw material for the manufacture of chemicals and fertilizer. As a result, a supply/demand imbalance exists in the United States and many other countries. Because of this imbalance, the price of natural gas is (and is projected to remain) too expensive for use in baseload (24-7) electric powerplants or as a substitute for gasoline or diesel fuel.

Petroleum. This hydrocarbon is also in high demand around the world and there is a corresponding supply/demand disparity. But even if the demand for petroleum were to decline or the supply to increase, we would not want – for environmental reasons – to boost global consumption of gasoline, diesel, and other petroleum-based fuels. Also, like natural gas, petroleum is an important raw material for the production of chemicals and other high-value products. A strong case can be made that at least some of the world’s finite oil and gas resources ought to be conserved for such uses.

Coal. Unlike oil and natural gas, coal is plentiful and inexpensive. The problem with coal – like one of the fundamental problems with petroleum – is that the combustion of coal creates air pollutants and carbon dioxide (CO2). Although government and industry have cooperatively developed new “clean coal” technologies over the last three decades, there is still significant public opposition to the construction of coal-fired powerplants. Such opposition arises because even the newest coal-fired plants emit criteria air pollutants (albeit at greatly reduced levels), airborne mercury, and millions of tons per year of CO2 (which many scientists believe to be a major force in global climate change).

Gasification. There is another hydrocarbon option, however, and it is gaining momentum. This alternative is gasification, a process by which coal or other low-value hydrocarbons are gasified in a large chemical reactor. The resulting synthesis gas is cleansed and then used to fire an electric powerplant and/or converted into high-value products such as synthetic fuels, chemicals, and fertilizers. What makes gasification a “breakthrough” technology is that it combines the economic advantages of coal with the environmental benefits of natural gas.




What is gasification?




Gasification is a term that describes a chemical process by which carbonaceous (hydrocarbon) materials (coal, petroleum coke, biomass, etc.) are converted to a synthesis gas (syngas) by means of partial oxidation with air, oxygen, and/or steam.

Modern gasification technologies generally operate as follows:

A hydrocarbon feedstock is fed into a high-pressure, high-temperature chemical reactor (gasifier) containing steam and a limited amount of oxygen.


Under these “reducing” conditions, the chemical bonds in the feedstock are severed by the extreme heat and pressure and a syngas is formed. This syngas is primarily a mixture of hydrogen and carbon monoxide.


The syngas is then cleansed using commercially available and proven systems that remove particulates, sulfur, and trace metals (e.g. mercury).


Gasification is truly a breakthrough technology. Although syngas has lower heating value than natural gas, it can still be used in highly-efficient combined cycle electric powerplants or to make many products presently made from natural gas, including ammonia fertilizers, methanol-derived chemicals, and clean-burning synthetic fuels.




How does gasification differ from combustion?




Combustion (or burning) is an exothermic (heat releasing) reaction between a fuel and an oxidizer and (for a carbonaceous fuel) may be expressed:

Fuel + Oxygen → Heat + Water + Carbon Dioxide

Gasification is an exothermic reaction between a carbonaceous fuel and an oxidizer in a reactor where the oxygen supply is limited (generally from 20 to 70 percent of the oxygen for complete combustion). The reaction may be expressed:

Fuel + Oxygen (limited) → Hydrogen + Carbon Monoxide (+ some Water & Carbon Dioxide)
-----------------------------------------------------------------------------------------------------------------------------

http://www.netl.doe.gov/technologies/coalpower/gasification/basics/5.htmlGasification Systems Technologies
Gasification Basics



OK, so what really goes on inside the gasifier?
Depending on its type, a gasifier may operate at temperatures up to 2,600ºF, which is more than 12 times the boiling point of water, and pressures up to 1,000 pounds per square inch, gauge (psig), which is about 68 times that of standard atmospheric pressure. When the feedstock particles enter the gasifier and move through its zones they undergo three thermal and chemical processes – the first two in very rapid succession and the third more slowly:

Pyrolysis (a chemical breakdown of complex compounds caused by heat) occurs as the particles heat up. Volatile substances such as tar, hydrogen, and methane are released and char, a combustible residue resembling charcoal, is produced, resulting in up to a 70 percent weight loss for coal. The properties of the feedstock determine the structure and composition of the char.
Oxidation (controlled burning) then occurs as the volatile products and some of the char react with air or oxygen to form carbon dioxide and carbon monoxide. This type of reaction is known as exothermic, because it produces the heat.
Reduction then occurs as the char reacts with the carbon dioxide and steam to produce carbon monoxide and hydrogen, with some methane, which together make up the gaseous mixture known as syngas. This type of reaction is known as endothermic, because it consumes the heat. Slag is left as a waste product.
The net result of all of the chemical reaction inside a gasifier is that gasification is exothermic – it gives off heat. However, the main product of gasification is the syngas.

http://en.wikipedia.org/wiki/Gasification.>

GASIFIER PROCESSES

Hopefully.

:hide:

--d!

Calling it a wood-burning plant allows it to be built with fewer emission controls.

These plants have to be watched very carefully once they are running. Operators have a huge financial incentive to feed them lower quality and potentially toxic fuels they were not designed for.