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(The prepared statement of James R. Garvey, president and director of research, Bituminous Research, Inc., follows:)

STATEMENT OF JAMES R. GARVEY, PRESIDENT AND DIRECTOR OF RESEARCH, BITUMINOUS COAL RESEARCH, INC.

Mr. Chairman and gentlemen of the committee, my name is James R. Garvey. I am president and director of research of Bituminous Coal Research, Inc., with offices and laboratory at Monroeville, Pa. BCR is an affiliate of the National Coal Association, which has offices here in Washington, D.C., and through this affiliation serves as the research agency for the bituminous coal industry.

My purpose in being here is to discuss the current status of methods for control of emission of oxides of sulfur from coal-burning powerplants. We welcome this opportunity because we feel that through such discussions a better understanding of the complexity of sulfur dioxide control measures will result.

Our organiaztion, representing the bituminous coal industry, and with financial assistance and technical guidance of the electric utility industry, through the Edison Electric Institute and the Association of Edison Illuminating Companies, has been engaged in research on sulfur dioxide control for the past 8 years. We believe substantial progress has been made, as it has by other groups, including the Bureau of Mines and the Department of Health, Education, and Welfare, both of which have worked extensively on this subject. However, while several technically possible solutions have been developed, none is currently available which can be considered economically practical.

We feel that the time for coordination of the activity of all groups concerned has arrived, and that through such coordination we will be able to develop a better understanding of this gap between technical feasibility and economic practicality, and perhaps such coordination will enable closing the gap in the near future. Accordingly, we support the idea proposed in S. 306, calling for the establishment of a technical committee, with membership representing the Department of Health, Education, and Welfare, the Bureau of Mines of the Department of the Interior, and the coal, petroleum, and electric power industries. We have omitted the Federal Power Commission because it is closely confined to strictly regulatory powers established by statute and probably should not be expected to expand its field of activity into problems of this nature.

As I stated, some research progress has been made toward a solution of control of sulfur dioxide emissions from coal-burning powerplants. With the permission of the committee, I would like to review briefly the state of the art and outline some of the work which is currently underway.

To appreciate fully the approaches to a solution which are currently being tried, one must have in mind the process by which the energy of coal is converted to electricity in the conventional powerplant. In such a plant, coal, usually of the order of 2 inch x 0 in size, a size which is suitable for rail shipment, is delivered to the powerplant. Such a coal might contain 3.4 percent sulfur. At the plant the coal passes to a mill where it is crushed to a fineness about equivalent of talcum powder. The fine coal is mixed with air and burned in a boiler. Most of the heat of the gases at temperatures of 2,500° is transferred to water to make steam which then goes to the turbines for production of electricity. The gases from combustion, still at about 880°, pass through an air heater where more heat is extracted by incoming cold combustion air. The gases, then at 325°, go to a very efficient ash collector where upwards of 99 percent of the ash is removed. On the average, this ash removed takes out with it about 10 percent of the original sulfur. The essentially fly-ash-free gases then pass to the stack and, if we used 3.4-percent sulfur coal, there will be emitted to the atmosphere approximately 3,000 parts per million sulfur dioxide and 30 parts per million sulfur trioxide.

These concentrations are diluted after they leave the top of the stack (stacks of several hundred feet in height) and mix with the air of the outside atmosphere. By the time the ground level is reached several miles away, the concentrations are with rare exception of the order of 0.1 parts per million.

While concentrations of sulfur dioxide of this low level are well below the limits accepted for continuous 8-hour exposure for persons working in industries where such gases are part of their everyday environment, it has nevertheless been arbitrarily decided that the stack emission concentrations shall not exceed 2,000 parts per million SO2. To achieve such a concentration in the conventional

powerplant will require the combustion of a coal having about 2.2 percent sulfur if we assume that 10 percent of it will be retained in the ash. Because coal for steam purposes containing sulfur contents of this level, and at reasonable prices, is not available in many areas, the research has been directed at determining a method for utilizing the higher sulfur coal and still achieving the stack emission concentrations which have been indicated to be satisfactory.

What is available now and what is conceivable for the future to enable achievement of this goal? Control of sulfur oxide emissions from a powerplant can be achieved in three areas; namely: (1) reduction of the sulfur content of the fuel prior to firing, (2) the development of a new concept of conversion of the heat energy of coal to electricity, and (3) the recovery of sulfur oxides after combustion but prior to passage of the gases to the stack. Let us look at each of theṣe and review its status. Because we have some cost data available, let us start with the processes for recovering sulfur dioxide and sulfur trioxide from the flue gases.

Since they produce a recoverable and potentially salable byproduct, the three processes listed in table 1 show the most promise for application in electric utility plants.

Process:

TABLE 1.-Most promising SO: recovery processes

Developed by

1. Catalytic gas phase oxidation BCR and Pennsylvania Electric Co. group. 2. Alkalized alumina absorption U.S. Bureau of Mines. 3. Reinluft char absorption__--- Germany.

The work on all of these processes has passed the laboratory bench-scale stage and is now entering the pilot stage. While some additional technical problems must be solved before technical feasibility can be assured, it is possible at this time to determine the approximate cost of such recovery processes. The range of costs, including credits for sale of the byproduct and also possible costs for disposal of the byproduct, are shown in table 2.

TABLE 2.—Approximate costs in cents per million B.t.u. of SO2 recovery systems— with credits

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The most optimistic cost at the present time is 4.4 cents per million B.t.u., the equivalent of $1.14 per ton of coal, and could run as high as 12.1 cents per million B.t.u., the equivalent of $3.15 per ton of coal. Since the average cost of coal delivered to utility plants last year was approximately 25 cents per million B.t.u. of $6.50 per ton, it can be seen that the incorporation of processes of this type at their present state of development will substantially increase fuel costs. The second approach to better control of sulfur oxide emissions is through pretreatment of the coal prior to combustion so as to reduce the sulfur content of the fuel entering the boiler. Sulfur occurs in coal in two primary forms, organic and as a mineral called pyrite. The organic sulfur is chemically combined with the coal and cannot be removed except by chemical processing. Pyrite can be removed mechanically, but because of the extremely small size of the pyrite particles in many bituminous coals, not all of them are amenable to cleaning to the low level required. Some of the work which our organization has done, however, indicates that it might be possible to reduce the pyritic sulfur content with special coal-cleaning equipment installed at the powerplant where coal pulverization to the fine size needed to release the small pyrite particles is already done as a part of the crushing step prior to burning the coal.

Reduction in the organic sulfur content of the coals will require a chemical pretreatment such as dissolving the coal and filtering out the ash and other undesirable materials prior to combustion. Some work along this line is being sponsored by the Office of Coal Research of the Department of the Interior.

The idea of converting the coal to a gas before combustion takes place is also being investigated. The advantage of this approach is that the gas can be more economically desulfurized prior to combustion because the volume of gases to be handled will be substantially less than the amount which is present after combustion.

The final approach for control of sulfur dioxide emissions from coal-burning plants lies in the development of new concepts for generation of electricity from coal. While these will not in themselves produce a sulfur-dioxide-free gas, they could so increase the efficiency of power generation that the fuel savings resulting would close the gap between technical feasibility and economic practicality of gas-cleaning processes. The ideas are being investigated by many organizations and they include magnetohydrodynamics, fuel cells, the use of gas turbines, and supercharged boilers.

As I pointed out, research is underway in all three areas of control of sulfur oxide emissions in powerplants, work both in the United States and abroad. Research on some of the more promising methods has reached the pilot stage which, in all research, becomes the point where research expenditures begin to mount rapidly. The piloting of any one of the several approaches I have mentioned will cost several million dollars-more dollars than are available from the low profits of the coal industry. We therefore urge that the committee appointed under S. 306 also study the means by which the research on potentially feasible sulfur oxide control processes is to be financed.

The CHAIRMAN. Mr. Rogers, any questions?

Mr. ROGERS of Florida. I would like to ask just a question or two. I noticed two things. You have been doing research for 8 years, I believe, on this problem of getting control over the sulfur dioxide? Mr. MULLAN. That is right.

Mr. ROGERS of Florida. And you say that progress has been made; however, none are currently available which could be considered economically practical. What are the results that you have been able to obtain from your research that would help to get rid of this problem?

Mr. MULLAN. This is a review, to a degree, of Mr. Garvey's statement. I will give you some of it.

Mr. ROGERS of Florida. Is this putting a stack higher, or what? Mr. MULLAN. Our particular research has not been along those lines. Our research has been to cover the removal of the resultants from the coal itself and removing it from the flue gases themselves. At the moment I would say that there are three processes which seem to merit further work on the removal from the stack gases, they being the catalytic gas phase oxidation, the alkalized alumina absorption, and the Reinlift Char absorption methods. The latter was developed in Germany. The alkalized alumina absorption method is the Bureau of Mine's method in cooperation with the Public Health Service. And the catalytic gas phase oxidation process is one that has been worked on in our own laboratory and, also, by the Pennsylvania Electric Co. Each of these three processes, though, are well removed from the bench-they are in a pilot stage. You can imagine the problems of taking any of these from a bench scale to a full scale size in a powerplant, which would be tremendous. I will say that there is a problem. You can imagine when we are talking of running a test in an area which would be, say, 22 to 3 inches in diameter, being able to extract the gases from that, and then taking this out to, say, the local station of Pepco where the stack is 30 or 40 feet in diameter, and scaling it up would be difficult.

At the present time the Public Health Service, as well as our own agency, is planning expansions of this activity. They have testified—

I am not sure whether before your committee or some other committee that they are planning a major project to evaluate these three methods.

Mr. ROGERS of Florida. Who is going to do that?

Mr. MULLAN. This will be the Public Health Service in cooperation with the Tennessee Valley Authority. Our own laboratory is considering continuing its research on both phases, the removal of the sulfur from the bulk, and the removal of the sulfur dioxide from the stack.

Mr. ROGERS of Florida. I notice that you have made some progress in reducing some of this.

Mr. MULLAN. Some progress has been made. The big problem that we have now is getting it into a practical device that can be applied to the facility.

Mr. ROGERS of Florida. Where it would be within economic feasibility?

Mr. MULLAN. Certainly, this is necessary.

Mr. ROGERS of Florida. Is it possible to bring out filters in these stacks at all?

Mr. MULLAN. There has been some work-you are speaking specifically of sulfur dioxide?

Mr. ROGERS of Florida. Yes.

Mr. MULLAN. There has been some work done on filters. And by adding a dolomitic lime to the fuel as it is burned. The conversion is then extracted. At the moment this has been done only on a small scale.

Mr. ROGERS of Florida. Has it proved feasible so far?

Mr. MULLAN. I would say technically feasible.

Mr. ROGERS of Florida. To use a filter and, also, to add water to the fuel?

Mr. MULLAN. In one case I am familiar with they were using dolomitic lime.

Mr. ROGERS of Florida. Could you present the committee with a little memorandum on what this has shown?

Mr. MULLAN. In fact, we could, probably. I am sure that we could get information on all of the processes.

Mr. ROGERS of Florida. I think that it would be helpful.

Mr. MULLAN. Unfortunately, Mr. Garvey was most familiar with the particular research. He is not here today.

(See testimony of James R. Garvey, p. 330.)

Mr. ROGERS of Florida. That is why I wanted to pursue it further. If you will furnish it for the committee it would be helpful. I know that in my area we are very much concerned about a plant where you see the smoke rolling out of the smokestack.

Mr. MULLAN. I might make the point that there are various contaminants.

Mr. ROGERS of Florida. I realize that. Thank you.

The CHAIRMAN. Dr. Carter.

Mr. CARTER. I believe that we can say that the industry wants to do everything that is possible. Certainly, we realize there is a great problem here and it affects the use of millions of tons of coal coming out of the States of Illinois, Indiana, and the like.

Thank you.

The CHAIRMAN. Mr. Satterfield?
Mr. SATTERFIELD. No questions.
The CHAIRMAN. Mr. Mackay?
Mr. MACKAY. No questions.

The CHAIRMAN. Mr. Gilligan?

Mr. GILLIGAN. Just one question. In your statement submitted to this Subcommittee on Public Health, at the conclusion of the statement it mentions that research is underway in all three areas of control of sulfur oxide emissions in powerplants, both in the United States and abroad. Research in some of the most promising methods has reached the pilot stage which, in all research, becomes the point where research expenditures begin to mount rapidly.

The piloting of any one of the several approaches I have mentioned will cost several million dollars-more dollars than are available from the low profits of the coal industry. We therefore urge that the committee appointed under S. 306 also study the means by which the research on potentially feasible sulfur oxide control processes is to be financed.

Have you any suggestions as to how such research should be handled?

Mr. MULLAN. You realize that there has been a time lag between Mr. Garvey's presentation before the Senate committee and this particular period here. I believe that the Public Health Service has made statements that they are contemplating that it will cost about $7 million for the three pilot studies. And in line with this a coinstitute is expanding is own research abilities.

Mr. GILLIGAN. Thank you.

The CHAIRMAN. Do you support Senate bill 306 insofar as it would provide for a technical committee to pursue research in this field?

Mr. MULLAN. Yes, we do. We feel that the formation of such a committee would give direction from your own committee that such activities would take place. Certainly, there is a speaking acquaintance between the various agencies concerned, but we believe that it would be better to tie all of these people together.

The CHAIRMAN. Do you support the position for grants to be made in connection with the research provided for in S. 306?

Mr. MULLAN. I believe that the grants are made relative to the automobiles.

The CHAIRMAN. Yes.

Mr. MULLAN. I made an earlier statement that we had no expertise relative to that phase of the legislation.

The CHAIRMAN. Do you not think that this committee should have such information? If you are not in a position to comment on this I suppose then that the committee should, also, consider the emission of fumes from automobiles?

Mr. MULLAN. My comments, sir, were specifically toward the problem of sulfur dioxide. I think that if you take and inject several other items into a specific program you tend to confuse the overall issue and get nothing out of a committee. If your committee would feel that it is necessary that there be a committee to study automobile exhaust fumes, I think that this committee should be made up of people with expertise in the subject. Certainly, the coal industry, to my knowledge, does not have that expertise.

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