Coal Firing Furnaces-New Hampshire and Vermont Series Part 1, a little about the past, present, and the future of coal, and the Coal Fuenace's Stoker: Although coal has always been an important and plentiful fuel source, many folks, just may not realize how long it has been used or how much it is used today.
The Past
Coal has been used for nearly as long as mankind has thrived. In fact, coal was used to provide heat in caveman times!
In the 1300s in what is now the United States, the Hopi Native Americans, living in whats now Arizona, used coal to bake their pottery made from clay. By the mid-1700s, the first U.S. coal mining operations opened in Virginia. In 1762 coal was used to manufacture, shot, shell, and other war material during the Revolutionary War.
Wood charcoal had long been used to provide fuel in England, but in the 18th century it was discovered that coal burned cleaner and hotter. Soon after, coal use skyrocketed during the Industrial Revolution, when demands for energy sources increased.
Coal was used to fuel the boilers on steam-powered trains, which became a popular mode of transportation in 19th-century America. At the same time, coal was being used in the production of weapons during the American Civil War, and coke (a coal residue) took charcoal's place as the primary fuel for making steel.
About one hundred years ago in the United States, coal's abundance led to its widespread use for heating homes, generating electricity, providing cooking heat, powering railroads and boats, and fueling factories.
In the 1940's, the cyclone furnace was developed. That new technology allowed the combustion of poorer grades of coal to be used that had less ash production and greater overall efficiency.
The Present
Although coal may not be as visible today as it was around 1900, it is even more prevalent as a source of fuel. Coal production has increased by more than 70 percent since 1970.
If you use electricity, chances are that you are a coal consumer. Nine out of every 10 tons of coal mined in the United States today is used to generate electricity. About 56 percent of the electricity used in this country is coal-generated electricity.
Electricity generation is just one use of coal in the United States. In addition, manufacturing plants and industries use coal to make chemicals, cement, paper, ceramics, and metal products, to name a few. Methanol and ethylene, which can be made from coal gas, are used to make products such as plastics, medicines, fertilizers, and tar.
Certain industries consume large amounts of coal. For example, concrete and paper companies burn coal, and the steel industry uses coke and coal by-products to make steel for bridges, buildings, and automobiles.
About 9 percent of U.S.-mined coal is exported to some 40 countries, including Canada, Japan, and western European nations.
The Future
The United States has a 300-year supply of coal, if it continues to use it at the same rate as today. This is promising because, in addition to the many existing ways to use coal, the future holds new methods and potential for growth. Products from coal may soon be part of communications and transportation systems, computer networks, and even space expeditions.
Coal will likely continue to be an important source of electricity generation because it is more abundant and cost-effective than oil and natural gas. Compare these energy costs per million British thermal units.
- Coal—$1.20
- Oil—$4.45
- Natural gas—$4.30
Although coal is widely used for electricity generation in the United States and in countries throughout Europe, there will likely be a significant increase in the use of coal for electricity generation in countries such as China and India.
In addition to these new and increased uses of coal, new technologies will continue to enhance our ability to identify the shape and composition of untapped coal reserves. Core samples and information about the layers of overburden (the topsoil, subsoil, and other layers of earth and rock covering the coal bed) can be analyzed before the expensive process of coal removal begins. New technologies will also continue to improve the effects of the production and use of coal on the environment.
The U.S. Environmental Protection Agency's Coalbed Methane Outreach Program seeks to work with coal companies to reduce methane gas emissions associated with coal mining. Since 1990, methane recovered and used productively at coal mines has increased from 13.8 Billion cubic feet to 37.2 Billion cubic feet.
Coal Firing Furnaces-New Hampshire and Vermont Series Part 1, about the stoker of a coal furnace: Its a mechanical device that was designed and constructed to automatically feed fuel to the coal furnace. Stokers are used in commercial, industrial, and home heating systems. By using a stoker, the result is a more efficient combustion owing to constant instead of intermittent firing. According to the ASHRAE's 1960 guide, coal stokers can be divided into four classes, by their coal burning capacity.
- Class 1 stokers (10 to 100 lbs per hour)
- Class 2 stokers (100 to 300 lbs per hour)
- Class 3 stokers (300 to 1200 lbs per hour)
- Class 4 stokers (over 1200 lbs per hour)
The class 1 stoker is used mostly in home heating installations. The other three classes of stokers are used in commercial and industrial heating systems.
Class 1 stokers are usually the underfeed kind and are designed to burn anthracite, bituminous, semibituminous, and lignite coal, and coke. Ash can be removed automatically or manually, with the latter method being the most popular.
Coal Firing Furnaces-New Hampshire and Vermont Series Part 1, stokers are also classified by whether the coal is stored in a hopper or bin. The disadvantage of the hopper design is that it will need to be refilled at least one every day. But the bin stoker design eliminates haven to handle the coal. Your coal is delivered to your home, by the supplier and placed right into the bin.
A underfeed stoker is usual used for home heating furnaces and boilers. This kind of stoker is one in which the fuel is fed upwards from underneath the home's furnace or boiler. The action of a screw or worm carries the fuel back through a retort from which it passes upwards as the coal above is being consumed. The ash is generally deposited on dead plates on either side of the retort, from which it can be removed.
Coal Firing Furnaces-New Hampshire and Vermont Series Part 1, a underfeed stoker can be designed to use either anthracite or bituminous coal, but the individual pieces of coal should be unifoem in size, and no larger than one inch in diameter. The coal should be treated with oil in order to eliminate dust. The worm feed mechanism can be regulated to feed coal at variable rates.
Fun Coal Facts
- The U.S. produces about 1.1 billon tons, of the world's coal supply, second only to China
- Coal generales about half of the electricity used in the U.S.
- More than 2 million acres of mined land has been reclaimed over the past 25 years, now thats an area larger than the State of Delawre.
- The U.S. has in the area of a 245 year supply of coal, that is if we continue to use coal at the same rate at which we use coal today.
- Montana is the State with the most coal reserves, 119 billion tons. But Wyoming is the top coal producing State, it produced about 400 million tons in 2004.
- Texas is the top coal consuming State. Folks use about 100 million tons evey year.
- The average coal miner is 50 years old and has 20 years of experience.
- Coal ash, is used as filler for tennis rackets, golf balls, and linoleum.
- U.S. coal deposits contain more energy than that of all the world's oil reserves.
- Each person in the U.S. uses 3.8 tons of coal each year.
Post 583 - 17 Sept. 2009
Link to Coal Firing Furnaces-New Hampshire and Vermont Series Part 2
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if you let the fire cool off for five to ten minutes before you go to remove it. Turn the stoker off and open the furnace's fire door to cool the fire. You can fill the hopper while the clinker is cooling. A clinker normally forms around the retort. Be sure to use a iron bar or poker to raise the clinker. Be sure not to dig in the retort. After you have raised the clinker, use a clinker tong to lift it from your furnace. A clinker can be in one piece or in several pieces, but be sure to remove all of it. Keep the fuel bed of your furnace clean. Remove the clinkers as often as necessary.
