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Facts About Coal Log Pipeline

What is coal log pipeline (CLP)?

Coal log pipeline (CLP) is an innovative emerging technology for coal transportation using pipelines. In the process of CLP, coal at the mine is first compacted into cylinders (logs) of a diameter 5 to 10% smaller than that of the pipe through which the coal logs are transported. The length of each log is usually twice the log diameter. Water is used to suspend and transport the logs through the pipe.

How much water is needed to transport coal logs through pipelines?

The coal-to-water ratio in a CLP is 3 to 4, depending on pipeline size. This means one pound of water can transport three to four pounds of coal in a CLP.

Is coal log pipeline the same as coal slurry pipeline?

No, coal slurry pipeline does not involve coal logs. It transports coal in slurry form - a mixture (paste) of fine coal particles in water. For coal slurry pipeline, the solid-to-water ratio is one. This means each pound of water transports only one pound of coal. Therefore, coal log pipeline (CLP) uses only one-third to one-fourth of the water needed by coal slurry pipeline to transport the same amount of coal.

Has coal slurry pipeline been used commercially?

Yes, coal slurry pipeline has been used in several countries including the United States. In fact, the U.S. has the world's largest and longest coal slurry pipeline - the Black Mesa Pipeline from Arizona to Nevada, over a distance of 273 miles. It is an 18-inch-diameter pipeline that transports 5 million tons of coal per year approximately. It has been used very successfully since 1970.

Has coal log pipeline been used commercially?

Coal log pipeline (CLP) is a much newer technology than coal slurry pipeline. CLP is actively being developed at the Capsule Pipeline Research Center (CPRC), University of Missouri-Columbia, with a strong participation from the Rolla campus as well. It will take at least two to three more years of active research and development before CLP can be reliably used commercially. Current plan calls for the completion of the development work in 1999. Longer time may be needed to complete the work if insufficient funds are available to carry out the planned remaining work.

Why is development of CLP needed? Why don't we just rely on the coal slurry pipeline?

CLP is superior to the coal slurry pipeline. In addition to requiring much less water, CLP also has the potential advantages of being more economical, dewater of coal being much easier, use of less energy to transport each ton of coal, and making clean-up much easier in the event of spills. Consequently, CLP is more attractive than coal slurry pipeline and will have a larger future market.

What are the remaining works in the development of CLP before it can be used commercially?

The remaining works involve conducting a large pilot-plant test, revising a manual of practice, revising a cost analysis of CLP, and select a commercial demonstration project.

What is the pilot-plant test?

The pilot-plant test involves constructing and testing an entire CLP system - designed and constructed similar to that of a commercial CLP except that for budgetary reasons the pilot plant pipeline is smaller and much shorter than any real future commercial CLP. The pilot-plant pipeline will use a 6" steel pipe 3,000 ft long. It will be made into a closed loop through which coal logs can be recirculated and tested over any distance. The testing of such a pilot plant is the last necessary step before commercial demonstration of CLP can be undertaken.

Why is the pilot-plant test necessary?

CLP is a sophisticated and costly technology that must be developed in steps before it can be used successfully commercially. The pilot-plant test will provide the information and data needed for designing the first commercial project of CLP - the commercial demonstration. Without the pilot-plant test, the adequacy and success of any commercial demonstration of CLP cannot be assured.

Has there been any interest expressed by any party in a commercial demonstration of CLP?

In 1996, CPRC conducted a national survey of coal companies and electric utilities to determine whether any of them had, and would be interested in submitting, a potential demonstration site (project). Any submitted demo project had to satisfy a set of stringent criteria such as the transportation distance must be less than 100 miles, and the throughput of coal (transportation capacity) must be less than 5 million tons per year. Eighteen projects were received and considered. Upon preliminary evaluation, three projects were found to be economically feasible. At present, the two most promising projects under active consideration are a 23-mile pipe for Potomac Electric and Power Company (PEPCO) in Maryland, and a 90-mile pipe for Southwestern Public Service (SPS) in Texas.

Why is commercial demonstration of CLP limited to relatively short (less than 100 miles) and relatively small (less than 5 million tons per year) projects?

Actually, longer and larger projects are more economical due to economy of scale for pipelines. However, for a demonstration project which is the first commercial project of its kind, it is not prudent to have the pipeline longer than 100 miles and pipe diameter larger than 10 inches. Otherwise, it would be too costly to modify the system after it is built. Being the first commercial project, there may be unexpected findings which would require system modifications in order for the system to operate smoothly and efficiently. Therefore, the first project (demo project) should be as small as possible and yet be economically feasible. If the project is too small (say less than 10 miles or of diameter smaller than 8 inches), it would be difficult to compete with truck or train economically, and hence cannot be justified on cost, unless it is a government subsidized demonstration project.

Is it possible to have government subsidy for the first commercial demonstration of CLP?

Yes, it is. On many occasions in the past, the U.S. government has subsidized costly demonstration of important new technologies to encourage their commercial use. However, Congressional approval is required before government subsidy will be available. Companies interested in having the government to subsidize a CLP demonstration project must justify through the Congressmen and Congresswomen from their states.

Where are CLP research and development (R&D) being carried out?

R&D in CLP has been carried out almost exclusively at Capsule Pipeline Research Center (CPRC), University of Missouri - both the Columbia Campus (UMC) and the Rolla Campus (UMR). This is so because CLP was invented by two UMC professors: Civil Engineering Professor Henry Liu and Chemical Engineering Professor Thomas R. Marrero. The Board of Curators of the University of Missouri owns two U.S. patents on CLP. Dr. John Wilson, Professor and Chairman of Mining Engineering, is also leading a research team at UMR conducting extensive R&D in CLP.

Who are funding (or have funded) research in CLP?

The R&D in coal log pipeline (CLP) at CPRC has been funded by a number of government agencies and private companies including the following:

Federal Agencies - National Science Foundation and U.S. Department of Energy

State Agency - Missouri Department of Economic Development

Private Research Organization - Electric Power Research Institute (EPRI).

Private Companies - Ameren Corporation (Union Electric Company); Arch Mineral, Corporation.; ARCO Pipe Line Company, Associated Electric Cooperative, Inc.; Gifford-Hill America, Inc.; Kansas City Power and Light (KCPL); Mid America Pipeline Company (MAPCO); Peabody Holding Company; Southwestern Public Services (SPS), Willbros Engineers, Inc.; Williams Pipeline Company; and Williams Technologies, Inc.

Small Businesses - Bonnot Company, COMPACTCONSULT, Inc.; Erie Press Systems; T. J. Gundlach Machine Co., Nova Tech, Inc., PERMALOK Corporation; PRO-MARK Process Systems, Ramer & Associates; STI International Associates, and T. D. Williamson, Inc.

In addition, a number of other companies have made generous donations of materials, equipment, services and money to CPRC, but are not official sponsors.

How much total funding has been provided for coal log pipeline (CLP) research so far, and how much more money is required before the CLP technology can be demonstrated commercially?

Since 1991, CLP has been under intensive R&D at CPRC. A total of $5 million (approx.) has been spent directly or indirectly in the R&D of CLP. Approximately $2 million will be needed in the future (in 1998 and 1999) to complete the pilot plant test - the last step of CLP development before this technology can be demonstrated commercially.

What are the main technical accomplishments made at CPRC in coal log pipeline R&D?

The main technical accomplishments include: (1) success in producing water-resistant and wear-resistant coal logs; (2) success in testing logs produced in a 5-mile-long existing underground pipeline in Conway, Kansas; (3) success in demonstrating a low-cost, highly-effective, hydrophobic binder for making coal logs; (4) demonstrated that by using a trace amount of a high molecular weight polymer, energy consumption in CLP can be greatly reduced (drag-reduction phenomenon); (5) discovered a new method to dissolve polymer in water which is far more effective than current methods; (6) discovered several ways to make good-quality coal logs and other compacted solids such as by modifying mold exit shape and using back pressure during coal log ejection from mold; (7) obtained two U.S. patents and three others are pending; (8) developed theories for predicting the hydraulics of coal log flow, the compaction of coal logs, the heating and cooling of coal logs, the water absorption rate of coal logs, and the automatic control of coal log system; (9) conducted a thorough research on important legal aspects of coal pipelines such as eminent domain rights, water rights, rights to cross railroads, etc.; (10) designed and constructed a unique machine (hydraulic press) to compact coal logs rapidly; (11) designed a second-generation coal log machine based on the rotary press concept; (12) developed a three-dimensional coal log compaction model which can be used to optimize the tools (molds and pistons) used for compacting coal logs; (13) designed a pilot-plant CLP - a 6" diameter 3,000-ft long closed loop pipeline complete with automatic injection/ejection, pump bypass, and waste water treatment facilities; (14) completed a most sophisticated cost model to determine the cost of transporting each ton of coal by CLP over any given distance, and to compare with the costs charged by trucks and railroads; (15) completed the first draft of a two-volume manual of practice for CLP, including a legal manual; (16) completed 35 MS theses (or reports), 10 Ph.D. dissertations, and 6 JDs; (17) published over one hundred papers on CLP in technical journals and conference proceedings which constitute the current knowledge in this new field.

Are coal logs water-resistant? Do they absorb water when moving through water-filled pipes?

Coal logs are rather water-resistant. They normally absorb very little water. The main reason for this is that coal logs are compacted under very high pressure. The high pressure squeezes air and water out of the pores, causing the pores to be saturated with water. The densified and saturated logs can absorb very little water.

If coal logs are saturated with water upon compaction, don't they contain too much water affecting burning?

No. Even though the logs are saturated with water, they contain less water than those in the raw coal. This is due to the fact that the high pressure used in compaction has squeezed out some of the water in the coal being compacted. The result is that the saturated coal logs actually contain less water than the unsaturated loose coal.

How to minimize the moisture content of coal logs?

In addition to using high pressure for compaction, the moisture in coal logs can be further reduced by using particle size distribution corresponding to the "maximum packing density," and by using an inexpensive hydrophobic binder such as Orimulsion.

Are coal logs wear-resistant in pipe?

Some are and some are not, depending on how you made them, and what kind of coal is used. The worst coal logs we made break up readily upon leaving the compaction mold; they are unsuitable for transport by pipeline. On the other hand, very strong logs can be and have been made. During the field test in Conway, Kansas, the worst logs broke up in the pipe but did not clog the flow, and the best logs lost only about 0.5% of weight during a 5-mile run through the pipe. In the laboratory, the strongest small logs (1.91-inch diameter) were circulated through a 2-inch-diameter pipe loop for a distance of 200 miles with 5% weight loss. Generally, the strongest logs are made from subbituminous coal mined at the Powder River Basin, Wyoming. The weakest coal logs made (i.e., the most difficult to compact) are compacted from anthracite coal.

Is coal log pipeline (CLP) cost effective for transporting coal?

A sophisticated and detailed cost analysis of coal log pipeline has been conducted at CPRC. The analysis calculates the anticipated price or tariff for transporting coal in dollars per ton for pipelines of various lengths. The tariff was determined from the cost plus a 12.5% after-tax return. This tariff was determined for CLP of various diameters (from 6" to 20") and lengths (from 10 miles to 2,000 miles), and plotted as a function of length and diameter (throughput). The results are then compared with the anticipated tariffs for slurry pipelines, trucks and unit trains. The results show that under ordinary conditions, large-diameter CLPs are more cost-effective than trucks for distances over 30 miles, approximately, and more cost-effective than unit trains for distances over 100 miles, approximately. CLPs are more cost-effective than coal slurry pipeline under most conditions. Details of the study can be found from the following paper: Liu, H., Noble, J., Wu, J. P. and Zuniga, R., "Economic Evaluation of a Coal Log Pipeline for Transporting Coal," Transportation Research: Part A, April, 1998.

Are there legal obstacles in future use of CLP? If so, what are they?

Yes, there are potential legal obstacles to the implementation of CLP. They are similar to those encountered by some coal slurry pipelines. These obstacles include lack of eminent domain rights in many states, possible refusal by some railroads to allow CLP to cross railroads, difficulties in getting water rights and permits to cross federal land and Indian reservations.

How should those legal problems be dealt with?

The best way to deal with these legal problems is through passage of new legislation (state laws) in states where proposed commercial coal log pipelines are to be located and where such laws are absent or inadequate. There are already eighteen states that have eminent domain rights either for coal pipelines or all types of pipelines. However, in states that don't have such laws, new laws can be passed provided that the public in those states wants to benefit from coal log pipelines. Therefore, it is important that planners of future CLPs must plan such pipelines with public interests in mind, and must educate the public in advance about the benefits that such pipelines can bring, in terms of new jobs created, lower utility rates, and the fact that CLP is very safe, very clean (non-polluting), does not occupy surface land, and uses much less water than coal slurry pipelines. Once the public realizes the benefits of CLP, it will approve new legislation to facilitate their construction.

For more information on legal issues concerning coal log pipeline, refer to the following papers:

Davis, P.N., "Legal Aspects of Future Coal Pipelines in the United States," Proc. of the 7th Int. Sym. on Freight Pipelines, Wollongong, Australia, July 1992, pp. 221-225.

Davis, P.N. and Liu, H., "Coal Pipelines Crossing Railroads: Legal Issues," Proc. of Spec. Conf. on Pipeline Crossings, American Society of Civil Engineers, Burlington, VT, June 1996, pp. 254-264.

Do you anticipate opposition from environmentalists and farmers? Some of them were opposed to the ETSI (Energy Transportation Systems, Inc.) coal slurry pipeline?

NO, because coal log pipelines uses much less water and poses no threat to the environment. In fact, the environment would be improved because using CLP will lead to fewer coal trucks on highways and streets, and fewer coal trains crisscrossing the nation. Consequently, less air and noise pollution will be generated by trucks and trains, and there will be less traffic congestion on highways and fewer accidents at rail crossings, etc. Use of coal logs will also mean less coal dust and cleaner power plants. Furthermore, once CLP is used commercially, it will lead to the development and use of other types of capsule pipelines for transporting grain, other agricultural products, solid wastes and so on. Farmers and the public will benefit from such new developments.

How does a CLP cross highways, railroads and rivers?

CLP crosses highways, railroads and rivers by tunneling underneath them, using modern technologies of directional drilling and micro-tunneling. Recent advancement in directional drilling technology allows pipes to penetrate deep underground over a maximum distance of about a mile, along a curved path. It allows new pipelines to be constructed across highways, railroads and rivers, without disturbing these roads and waterways.

What form of energy does CLP use? How much?

CLP uses electricity. In the U.S.A., the bulk of electricity is generated from domestic sources such as coal, nuclear and hydropower. In contrast, trains and trucks use diesel, most of which comes from imported oil. Therefore, the use of CLP also reduces U.S. reliance on foreign oil and helps to reduce trade deficit. CLP is also far more energy efficient than trucks for transporting coal.