- Details
We've been documenting how the by-products of our coal use, such as Carbon Dioxide and Coke Oven Gas, can be collected, and then combined with coal to actually enhance the efficiency and productivity of coal conversion processes designed to produce, as end products, liquid fuels and chemicals, or plastics manufacturing feed stocks.
From China, where a truly intensive coal-to-liquid conversion industrial development is underway, comes this research result confirming that a steel-making by-product of coal use, from the coking process, Coke Oven Gas, can be combined with coal to enhance and improve the hydrogenation of coal into valuable hydrocarbons, such as liquid fuel.
As follows:
"Co-pyrolysis of coal with hydrogen-rich gases. 1. Coal pyrolysis under coke-oven gas and synthesis gas
Hongqiang Liao, Baoqing Li and Bijiang Zhang
State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, Shanxi 030001, China
Abstract
To improve the economy of the hydropyrolysis process by reducing the cost of hydrogen, it has been suggested that cheaper hydrogen-rich gases (such as coke-oven gas, synthesis gas) could be used instead of pure hydrogen. Pyrolysis of Chinese Xianfeng lignite was carried out with real coke-oven gas (COG) and synthesis gas (SG) as reactive gases at 0.1–5 MPa and at a final temperature up to 650°C with a heating rate of 5–25°C min−1 in a 10 g fixed-bed reactor. The results indicate that it is possible to use COG and SG instead of pure hydrogen in hydropyrolysis, but that the experimental conditions must be adjusted to optimize the yields of the valuable chemicals."
Another point to be made is that the Chinese researchers seem to indicate that "recycling" the synthesis gas derived from the coal decomposition back into the pyrolysis of more coal also improves the hydrogenation process.
But, definitely: A coal-use by-product of steel-making, coke-oven gas, which was once a troublesome and polluting effluent, can be collected and added to coal as an additional raw material which enhances and improves the conversion of coal into liquid fuel.
- Details
We had earlier reported the US Air Force's synthetic fuel development program; documented some test flights that had been made in the C-17 using coal-derived synfuel; and referred you to some universities where the program's research has been underway.
Herein, we document that the venerable B-52 bomber is now certified to operate on a blend of standard jet fuel and Fischer-Tropsch fuel made from coal.
The extended excerpt, with comment following:
- - "8/8/2007 - EDWARDS AIR FORCE BASE, Calif. (AFPN) -- Secretary of the Air Force Michael W. Wynne announced the completion of the Air Force's certification of the Fischer-Tropsch fuel blend in the B-52H Stratofortress during a signing ceremony here Aug. 8.
The signing ceremony certified that the blended FT and JP-8 fuel is safe for operational use in all B-52H aircraft and marked the formal conclusion of testing.
"The demonstration approach approved by Secretary Wynne in April 2006 identified five execution steps," said Maj. Gen. Curtis Bedke, Air Force Flight Test Center commander. "The final execution step began on Sept. 19, 2006. A B-52 was flown at Edwards with two engines running synthetic fuel and the remaining six engines on JP-8 fuel. On Dec. 19 2006, the B-52 was flown with all eight engines on the FT blend."
The B-52H was chosen as the test platform because of key advantages such as its eight engines, he said. The fuel system can simultaneously isolate, carry and manage both a test fuel and the standard JP-8 fuel.
The Air Force plans to test and certify every airframe to fly on a domestically produced synthetic fuel blend by early 2011.
"When I asked that this development be done, the people at Wright-Patterson Air Force Base, Ohio, and the Air Force Flight Test Center were excited to push this technology on behalf of the Air Force and America," said Secretary Wynne.
Every time the price of fuel goes up $10, it costs $600 million for the Air Force, he said.
"It causes angst to know that we're faced with a commodity that some might use against us," Secretary Wynne said. "We want to provide our nation a look forward to something else and to essentially join with numerous researchers who are looking for alternatives whether it is ethanol, switch grass, biomass or Fischer-Tropsch and finding the solution. I think it is going to be a tremendous partnership across the board."
One of the things planners are looking forward to is a clean coal to liquid manufacturing process, he said.
"It may involve several manufacturing steps to essentially neutralize carbon usage and get us to what we want," Secretary Wynne said. "We want a synthetic blend that will not interrupt the flow of fuel in our aircraft and airfields and will be a viable substitute."
A 50 percent blend appears to be the right answer, he said.
There are universities across the country trying to determine why we stopped at 50 percent, Secretary Wynne said.
"So the question is how do you bring this all to fruition?" he said. "For many years into the future, it is going to be very difficult to get more than a 50/50 blend on a real basis and not in a laboratory."
Testers are very pleased with the FT fuel's performance thus far, he said. The fuel may also reduce maintenance needs.
The next aircraft to be certified for FT fuel is the C-17 Globemaster III.
"This will be a bridge into the commercial arena," Secretary Wynne said. "We are being watched by many of our airline colleagues who are not only partnering with us, but researching our data. We have developed a rigorous process to qualify this fuel and any manufactured, processed synthetic fuel and blend."
The Air Force manual is being rewritten to highlight that there is a process to qualify alternative fuels within the Air Force, he said.
Recently, the Air Force ordered 281,000 gallons of synthetic fuel for further testing on the C-17 and B-1 Lancer engines in the coming year. NASA is also interested in synthetic fuels and will receive 9,000 gallons of synthetic fuel from the Air Force so they can begin evaluating its use in various engines and systems.
"This is the tip of the spear for national energy independence and cleaner energy," Secretary Wynne said. "It is doing well for the Air Force and the nation.""--
The signing ceremony certified that the blended FT and JP-8 fuel is safe for operational use in all B-52H aircraft and marked the formal conclusion of testing.
"The demonstration approach approved by Secretary Wynne in April 2006 identified five execution steps," said Maj. Gen. Curtis Bedke, Air Force Flight Test Center commander. "The final execution step began on Sept. 19, 2006. A B-52 was flown at Edwards with two engines running synthetic fuel and the remaining six engines on JP-8 fuel. On Dec. 19 2006, the B-52 was flown with all eight engines on the FT blend."
The B-52H was chosen as the test platform because of key advantages such as its eight engines, he said. The fuel system can simultaneously isolate, carry and manage both a test fuel and the standard JP-8 fuel.
The Air Force plans to test and certify every airframe to fly on a domestically produced synthetic fuel blend by early 2011.
"When I asked that this development be done, the people at Wright-Patterson Air Force Base, Ohio, and the Air Force Flight Test Center were excited to push this technology on behalf of the Air Force and America," said Secretary Wynne.
Every time the price of fuel goes up $10, it costs $600 million for the Air Force, he said.
"It causes angst to know that we're faced with a commodity that some might use against us," Secretary Wynne said. "We want to provide our nation a look forward to something else and to essentially join with numerous researchers who are looking for alternatives whether it is ethanol, switch grass, biomass or Fischer-Tropsch and finding the solution. I think it is going to be a tremendous partnership across the board."
One of the things planners are looking forward to is a clean coal to liquid manufacturing process, he said.
"It may involve several manufacturing steps to essentially neutralize carbon usage and get us to what we want," Secretary Wynne said. "We want a synthetic blend that will not interrupt the flow of fuel in our aircraft and airfields and will be a viable substitute."
A 50 percent blend appears to be the right answer, he said.
There are universities across the country trying to determine why we stopped at 50 percent, Secretary Wynne said.
"So the question is how do you bring this all to fruition?" he said. "For many years into the future, it is going to be very difficult to get more than a 50/50 blend on a real basis and not in a laboratory."
Testers are very pleased with the FT fuel's performance thus far, he said. The fuel may also reduce maintenance needs.
The next aircraft to be certified for FT fuel is the C-17 Globemaster III.
"This will be a bridge into the commercial arena," Secretary Wynne said. "We are being watched by many of our airline colleagues who are not only partnering with us, but researching our data. We have developed a rigorous process to qualify this fuel and any manufactured, processed synthetic fuel and blend."
The Air Force manual is being rewritten to highlight that there is a process to qualify alternative fuels within the Air Force, he said.
Recently, the Air Force ordered 281,000 gallons of synthetic fuel for further testing on the C-17 and B-1 Lancer engines in the coming year. NASA is also interested in synthetic fuels and will receive 9,000 gallons of synthetic fuel from the Air Force so they can begin evaluating its use in various engines and systems.
"This is the tip of the spear for national energy independence and cleaner energy," Secretary Wynne said. "It is doing well for the Air Force and the nation.""--
We won't repeat Secretary Wynne's final sentence, but every one of our elected reps should commit it to memory, with the understanding that by "it", Wynne means "coal".
We do want to repeat one passage that echoes other reports on FT fuel performance we have cited:
"Testers are very pleased with the FT fuel's performance thus far, he said. The fuel may also reduce maintenance needs."
If you've followed our dispatches thus far, you'll know it to be a frequent observation that coal-based, "FT", liquid fuels deliver better fuel economy and result in less engine wear than their petroleum-based counterparts.
- Details
We have documented in some general detail the indirect processes, such as Fischer-Tropsch, for coal liquefaction.
In brief summary, a "syngas" is generated by the thermal decomposition of coal in a low-oxygen atmosphere, which is then passed over an Iron-group metal or zeolite catalyst that condenses the syngas into liquid hydrocarbons, which, like crude oil, can then be refined into ethanol, methanol, diesel, gasoline, and other useful liquids.
That's a gross over-simplification, of course, but captures the rough outline of the process.
We're certain you're at least generally familiar with "coke" - the high-carbon residue produced by the low-oxygen roasting of coal - which is used in traditional steel-making processes.
Coke ovens in steel and coal country were once fairly common sights, especially visible at night, when they appeared as dull orange spots glowering on the dark hills.
The purpose of "coking" was to drive off the volatile components, including impurities like sulfur, so that a more pure, less contaminating, carbon product was produced for refining iron ore and making steel.
The volatile gases, driven from the coal by the coking process - the "coke oven gas" - are flammable. They were at first vented to the atmosphere - "flared"; but, later refinements allowed for them to be captured and used, either as fuel for the coke ovens themselves or as supplemental fuel for the steel mill furnaces.
The coking process does generates other products, and the following link, from which the table below it is extracted, can provide more detail; with additional comment following:
| Stream | Destination | Typical quantities, based on 1 million tons per year coke |
| Coke Oven Gas | Used as fuel gas at the coke oven battery and steel works | 50 million std.cu.ft./day |
| Flushing Liquor | Recirculated back to the coke oven battery | Varies with plant design |
| Waste Water | Discharged to treatment plant | Varies with plant design |
| Tar | Sold as product | 29,000 gallons/day |
| Ammonia/Ammonium Sulfate | Sold as product | 12 tons/day (as ammonia) |
| Light Oil (if recovered) | Sold as product | 12,500 gallons/day |
| Sulfur/Sulfuric Acid (if gas is desulfurized) | Sold as product | Varies with coal properties and local requirements |
Our focus is on the organic products of coking, but you can see that other useful by-products are also generated.
Next, we direct your attention to:
An excerpt:
"The 120 000 t/a methanol project based on coke oven gas designed by the Second Design Institute of Chemical Industry started production in Kingboard (Hebei) Coking Co., Ltd. on Sept. 5. The product reached the standard for AA-grade products in the United States. The capacity of this unit is 40 000 t/a higher than the first methanol unit based on coke oven gas in China complete in Qujing, Yunnan province in December 2004."
What all this adds up to is this:
In both indirect and direct (i.e., WVU's West Virginia Process) technologies for converting coal into liquid hydrocarbons suitable for fuel and plastics manufacturing, the coal, and it's intermediate products, must be "hydrogenated". WVU, in their direct coal liquefaction technique, as we understand it, use the solvent tetralin as the hydrogen donor.
Indirect CTL processes, such as Fischer-Tropsch and Bergius, use hydrogen derived from the coal itself, but there isn't enough to "go around". Much carbonaceous "slag" is generated, and a lot of the carbon is wasted. It has been suggested, perhaps in some places experimented with or reduced to practice, that the inclusion of biomass, or even pure hydrogen electrolyzed from water, could enable the necessary hydrogenation.
Herein, we have illustrated the possibility that an otherwise objectionable, hydrogen-rich by-product of coal use in the steel industry, coke oven flue gas, can be captured and recycled, as is, according to the above citation, apparently being done in China, into the process of converting coal into liquid hydrocarbon fuels.
We'll note also the co-production of fertilizer (ammonia), as well as other materials from which potential fuels could be derived - tar and light oil - in the coke-making process.
So, the possibility exists, as might be being realized in China, given the steel-making companies publicly known to be involved in their massive CoalTL industrialization program, to site, in an efficient and environmentally-beneficial way, a coal-to-liquid conversion facility next to a steel mill with an integral coking plant, to utilize coke oven gas as a co-feed in the synthesis of liquid hydrocarbon fuels, such as methanol, from coal.
As we've said many times: Our use of coal doesn't generate pollutants, just valuable by-products.
- Details
Control Of Emissions From Lurgi Coal Gasification Plants.
Our own US EPA issued this report on Lurgi-type coal gasification processes - the starting point technology, as we understand it, for Sasol's extensive industrial operations which convert coal into liquid fuels.
Some excerpts, with one, especially, noted below:
"The purpose of this document is to provide information on Lurgi Coal Gasification Plants, their emissions, control technologies which can be used to control emissions, and the environmental and economic impacts of applying these control technologies. This document is being issued to assist State, local, and Regional EPA enforcement personnel in the determination (on a case-by-case basis) of the best available control technology for Lurgi Coal Gasification Plants.
| Descriptors: | Air pollution; Coal gasification; Desulfurization |
| Date: Reference #: | 1978 A.78.5 |
| Availability: | Yes |
| EPA Office: | Office of Air and Radiation |
| Office Suboffice: | Office of Air Quality Planning and Standards |
| Office Division: | Emission Standards and Engineering Division |
| EPA Author: | NR |
| Document Type: | Cost Analysis |
| Contractors: | NR |
| Document Status: | Final |
| Pages: | 118 |
Note the year this study was performed. No further comment on that, and the changing nature of US political governance during the interim. But, after 118 pages, our US EPA came to this one cogent conclusion about gasifying coal to make liquid fuels:
"Most of the Sulfur can be recovered as a salable product." (Quote is directly excerpted from the report. We are unable to provide a precise citation due to the nature of published summaries available to us. - JtM.)
Well, at least we now know that.
But, as we earlier documented, some sulfur compounds, which perhaps could be derived from the raw coal itself, actually facilitate and make more efficient the actual process of coal liquefaction.
As we've been saying all along: Converting our abundant coal into needed liquid fuels doesn't generate pollutants. It does, though, create valuable by-products.
- Details
We're sending the abstract of this German study to affirm some points we've been attempting to document for you. Comment follows the excerpt:
| "Title | Quantitative investigations into the environmental impact of coal gasification and hydrogenation plants |
|---|---|
| Creator/Author | Juentgen, H. ; van Heek, K.H. ; Kirchhoff, R. ; Klein, J. |
| Publication Date | 1983 Feb 01 |
| OSTI Identifier | OSTI ID: 5176028 |
| Other Number(s) | Journal ID: CODEN: CHIUA |
| Resource Type | Journal Article |
| Resource Relation | Journal Name: Chem. Ind. (Duesseldorf); (Germany, Federal Republic of); Journal Volume: 35 |
The background and evolution of coal gasification and hydrogenation is discussed and those parameters affecting the emissions from installations of this kind, namely the feed coal, product, type of process and efficiency of the purification plant are assessed. Data are presented on several conversion techniques (Lurgi, Texaco, etc.) and three gasification processes and one hydrogenation process currently in operation are examined. The estimated emission levels are presented (SO/sub 2/, dust, etc.) and the effectiveness of the extraction methods used are discussed. An assessment is made of the long-term potential for coal gasification by application of nuclear process heat. Finally, other factors are discussed, such as plant breakdown, leakage sources and the emission of trace elements. It is concluded that coal gasification and hydrogenation on an industrial scale can generally be regarded as environmentally compatible."
First of all, this report is from Germany, where the technologies for coal conversion to liquids, via gasification and hydrogenation, were reduced to industrial practice in WWII.
Second, the report was made in 1983, but coal conversion is discussed herein as if it were a widely-known, understood and commercially-practiced technology, not some fanciful, unattainable goal only practiced by alchemists using fabled processes in distant lands.
But, finally, the main point we want to make herein is under-stated by the researchers, in typical Germanic fashion, in the final sentence: "It is concluded that coal gasification and hydrogenation on an industrial scale can generally be regarded as environmentally compatible."
To sum it up; and to repeat with some logical extrapolation: Turning coal into gasoline "can generally be regarded as environmentally compatible".
Join Friends of Coal
Be part of West Virginia's coal industry future. Together, we can continue building a stronger, more prosperous Mountain State by supporting our miners and communities.
West Virginia Coal Association
The West Virginia Coal Association has been the voice of the coal industry for over 100 years, advocating for safe, responsible mining practices and supporting the communities that depend on coal.
Join the FOC
Become a Friend of Coal and download our app to stay connected and support the industry.
