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EXPERIMENT IN MANUFACTURE OF ALUMINA FROM (LAY
Mr. DIRKSEN. I have one question about your alumina situation. Two years ago, I believe, we gave the Bureau of Mines in the Department of the Interior $65,000 with which to set up a pilot plant for the purpose of ascertaining a short cut or new method of deriving alumina from clay, and aluminum from alumina. Some new process came over heer, I think the French process, which is on a flotation basis rather than the type that Alcoa uses. I chased it throngh the Bureau of Mines and had some little thing to do with it, and it was finally tested out and, insofar as I know, was approved.
Now it became necessary, of course, to get clearance from the War Production Board and I think, as a matter of fact, it rests there at the present time without clearance, on account of critical materials. But I am interested in those studies and the possibility of the manufacture of aluminum from a process of this kind because of the critical situation in aluminum at the present time, and I would like to have you tell us about that, either on or off the record.
Mr. LILIENTHAL. The Walthall process, as we call the T. V. A. acid process, after the T. V. A. chemist who invented it, has been proved beyond any question as being technically feasible. We have made alumina (several members of the committee have seen it from ordinary white clays that are very common in the country.
Mr. DIRKSEN. The basic approach is that you can get alumina from low bearing clays, as I understand; you do not have to have a special deposit?
Mr. LILIENTHAL. Clays are relatively high in alumina. which, of course, is present in all of the earth's surface, but these particular clays are relatively low in impurities. But that is the only difference between the clays we use and any of the earth around us.
The Walthall process has been subject to reexamination by the best consulting board we could get in the country, of industrial engineers and professors of metallurgy. As a new process it is in competition for approval, chemically, and in the purity of the product, with the older Bayer process.
The Bayer process, which I suppose is 50 or 60 years old, has been refined and improved and the cost lowered in a large-scale operation over the years—you would not have to be very perceptive to guess what kind of comparison we would get. Naturally the Bayer method in a large commercial operation would show up better, when compared to results obtained in a pilot-plant operation-although ours is a relatively large pilot plant, but still not a commercial plant.
The importance of the operation, as we have sought to make clear over a period since before the beginning of the European war, was that it was a kind of insurance against that treacherous piece of water between here and South America, and important as a measure to conserve the high-grade bauxite in this country. We have not been persuasive about that. Some of the technical men who examined the process on behalf of W. P. B. may have had some difficulty in being disinterested in judging a new process because it is human nature to resist new things you are not accustomed to; but that this process will be used on a commercial scale before very many years, is perfectly clear.
At the moment, while there are great difficulties in getting this high-grade bauxite from South America, the situation is that while alumina is now tight and the supply tight, the W. P. B. is persuaded that it will take fewer critical materials to expand the bauxite plants using the old Bayer process, using domestic high-grade bauxite and in addition using a new process on domestic low-grade bauxites rather than to build a plant using the Walthall process.
The use of domestic low-grade bauxites involves a new process too; it has bugs in it. Nobody seems to know, or has been willing to tell us at least, what it is going to cost. But on the comparative use of critical materials which they have a better chance than we to judge, it may be that such a decision proves to be right. Our own people are disappointed. We have worked 7 years at this process, in a large pilot plant. It might have been money well spent to have built a commercial-size plant, not large enough to affect the total supply, but large enough so as to prove the operation. Naturally, when you have been working hard on that kind of project, you get
elings into it. We try to avoid that. The best evidence of that is that we have recently agreed, as being probably the agency best qualified technically in the clay field, to develop another kind of clay process, known as the modified Pederson process, with funds furnished by W. P. B. We are conducting these tests at Muscle Shoals.
I am not too happy about the W. P. B. decision. I think the Wathall process is a hedge that might better have been taken, but these other men have the responsibility and they are all able fellows. But, as to the future, this seems to me awfully important: that the Federal Government should not fail to do anything necessary in order to have a stand-by of this kind of clay process against the hazard of future wars; because, in the meantime, we will have been drawing enormously on our high-grade domestic deposits and will have drawn very heavily on our low-grade domestic deposits; so that, when this war is over, it looks as if there are only two alternatives open; one is clay, and the other is to keep the lines from South America open, no matter what happens. So that we feel, even though present conditions will not permit the construction of a commercial size plant, the way things now are, we look on the process as insurance.
I would like to supplement that with some factual material. Mr. WOODRUM. All right, sir. (The supplementary material follows:)
RESEARCH ON ALUMINUM FROM CLAY-STATUS AS OF DECEMBER 1942
The Tennessee Valley Authority can now report that the Walthall process for producing alumina from clay is farther advanced in pilot-plant tests than any of the many clay processes on which research is being conducted over the country. This fact is of great importance in assessing the status of raw-material supply for the country's great aluminuin production program. For that reason we want to describe the Authority's work in this field in some detail.
In testimony before this committee last year, we announced that our research work in the development of the Walthall process for the production of aluminum from clay had culminated in success and that the Office of Production Management had appointed a committee to study our reports and look over our pilot plant.
The meeting with this committee was held as planned and, in order to bring you up to date on the project, we shall give you in brief a complete history of it.
For the last 5 years Tennessee Valley Authority has been actively carrying on extensive research to develop a process for the production of aluminum from clay
of the type which exists in large deposits in the Southeast and other parts of the country. This clay contains 30 to 35 percent aluminum oxide and about 1 percent of iron oxide, the remainder being mostly silica. It is a type of clay which exists in great abundance, and there are many deposits now being used. It is, therefore, of low value and a cheap potential raw material. Certain deposits in western Tennessee have been thoroughly explored, and an available reserve of millions of tons has been proved. Large deposits of similar clays also exist elsewhere, notably in Georgia.
As a result of its research, the Authority has developed a method for extracting aluminum oxide from such clays, which is known as the Walthall process. This is an acid process, consisting of treating the clay with sulfuric acid and recovering aluminum oxide from the solution. A pilot plant having a capacity of a few hundred pounds of clay per day has been built and operated intermittently over a period of more than 2 years to develop and test the various steps. Testing a new process in a pilot plant of this size is quite different from testing a new process by test-tube work in the laboratory. The Authority's pilot-plant tests have led to conclusions as to technical feasibility of the process and preliminary estimates of its economics that are far more reliable and realistic than any conclusions drawn from small-scale laboratory work of test-tube scope. Our pilotplant tests come as close to simulation of commercial operations as is possible without actually building and operating a commercial scale plant. The product of this pilot plant is aluminum oxide, which is susceptible to reduction to aluminum metal in electrolytic cells similar to those now in use commercially. Operation of this pilot plant demonstrated that the production of aluminum oxide from clay by the Walthall process is technically feasible.
Since aluminum is one of the most critical war metals, the Authority felt that the Walthall process, which makes it possible to use domestic clays as a source of aluminum, might constitute a valuable contribution to the war effort. Consequently, in November 1941, as stated before this committee last year, Tennessee Valley Authority submitted a proposal to Office of Production Management for the construction of a plant to utilize domestic clays and Tennessee Valley Authority electric power in the production of aluminum metal.
Following this proposal, technical representatives of Office of Production Management reviewed the Walthall process an January 1942. They stated that in their opinion the product of the pilot plant at that time was not nearly pure enough for the manufacture of aluminum. However, there was promise, they felt, that by changes in the process this situation could be corrected, at least in great measure.
Subsequently, during the 1942 calendar year, considerable time and effort have been spent in improving the performance of the pilot plant, and the purity of the aluminum oxide produced has been improved considerably. Aluminum oxide analyzing better than 99 percent Al,03 has been produced consistently. For comparison, commercial Bayer alumina contains approximately 99.2 percent Al,03.
It is, of course, inevitable that the specific impurities present in aluminum oxide produced from clay by an acid process will differ from those in aluminum oxide produced from bauxite by the alkaline Bayer process which is now in commercial use. The question of effect of these iinpurities (present in Walthall aluminum oxide to the extent of less than 1 percent) on the production of metal can best be determined by practical manufacture of metal from the oxide.
With a view toward getting at this effect, a very small electrolytic cell has been operated. Experiments to date have indicated that metal can be produced from the Walthall aluminum oxide which is equal in purity to that produced from commercial aluminum oxide when both operations are carried out in our experimental cell. However, because of the small size of the cell, it was not possible to produce metal quite equaling the highest-grade commercial specifications either from Walthall aluminum oxide or from the aluminum oxide now used by the industry in its metal production. For the same reason it is impossible to draw any conclusions as to the relative cost of operating the cell with the two different materials.
The present status of the alumina-from-clay research may be summarized as follows:
1. While a considerable number of clay deposits are known to exist, the extent and quality of at least one large, advantageously-located consolidation of suitable clay available at low cost have been definitely proved.
2. An acid (Walthall) process for the extraction of aluminum oxide from clay has been developed and shown to be technically feasible by operation of a pilot plant.
3. The quality of the aluminum oxide produced from clay by the Walthall process differs somewhat from that of the commercial product now in use. Small-scale experiments have indicated, however, that this aluminum oxide can be used to produce metal approaching very closely the quality of the highest grade aluminum now used commercially.
4. While the economics of the process cannot be definitely determined until commercial scale operations are undertaken, the cost of producing aluminum
from clay utilizing the Walthall alumina process (for preliminary production ther of the oxide) has been estimated at 15 cents per pound,
A second meeting with (Office of Production Management) War Production Board representatives is scheduled for the early future to review results obtained in the recent pilot-plant tests.
It is frankly recognized that the decision of the War Production Board to augment nondomestic sources of bauxite by using low-grade domestic bauxites affords little hope that the Walthall process or any other clay process will be used in large-scale production of aluminum metal during the war. It is believed, however, that the ready availability of several tested clay processes is good insurance for a certain supply of alumina to support the Nation's expanded aluminum-production program, particularly in view of the possibility of a long war. For this reason the Authority is also working on the modiíied Pedersen processan alkali process--at the request and expense of the War Production Board. Tois process is not as fully tested aand developed as the Walthall process but, in the judgment of War Production Board, it has shown sufficient promise to warrant further development,
The need for a clay process is clearly greater now than when we began our work 7 years ago, because in the early future, due to shipping hazards, our reserves of domestic high-grade bauxite will be seriously depleted, leaving us fully dependent upon low-grade bauxites and domestic clays should imports of bauxite ever be cut off again. We must therefore have fully developed clay processes available if we are to have a guaranty of domestic self-sufficiency of aluminum production in time of war.
MUNITIONS AND FERTILIZERS
Mr. LILIENTHAL. The only other item involving large amounts in the Budget estimate relates to the Muscle Shoals properties. It is covered beginning with page 22 in what is there called the fertilizer program, because that is what it was called before, and we did not want to confuse things by changing the title; but it is actually a munitions and fertilizer program.
Mr. STARNEs. That is in keeping, of course, with the original concept of setting this up to manufacture fertilizer in peace, and nitrates or other elements in war?
Mr. LILIENTHAL. Yes. Mr. STARNES. That was part of the whole original concept of World War No. 1.
Mr. LILIENTHAL. I thought it might save time to have this chart (exhibiting] just to indicate what has been happening as a result of the war, on these properties of Muscle Shoals, where we have been producing phosphorus for various kinds of phosphatic fertilizer. This chart is in terms of P,0s, the oxide of phosphorus, not tons of product, although the tons are given separately. But you see in this war situation, most of the output is for chemical warfare and that output is very large.
The next largest, I believe, is concentrated fertilizer, the superphosphate, denominated here as “lend-lease.” That is for shipment to Great Britain. The thought there is that this being such a highly concentrated material, a great many bottoms are saved by sending
the concentrated material to Britain, to be put on the soils there to raise cereals and other foods, rather than shipping the low-grade 16 to 20 percent material made by other methods.
Mr. Starnes. What do you call that high-grade fertilizer?
Mr. LILIENTHAL. Triple superphosphate and calcium metaphosphate.
Mr. DIRKSEN. In tonnage, that would be how much?
Mr. LILIENTHAL. In the fiscal year 1943, 26,000 tons of P,0, in lend-lease materials; in the 1914 fiscal year, an estimated 21,400 tons. That leaves a balance for the domestic program, which has been the major portion, of a relatively small 16,500 in the 1943 fiscal year, and 13,534 in the fiscal year 1944.
That is a visual explanation of the change in the utilization of the plant.
Now, returning to these physical properties at Muscle Shoals that basically were a part of an inheritance from World War No. 1, I want to call attention to the ammonia and ammonium nitrate plant, which is in operation.
That was not financed through the T. V. A. budget; but, of course, was financed through this committee as part of the War Department appropriation, by transfer to us. We have included, because we thought you ought to have it before you. It begins on page 44 with the "Design, construction and rehabilitation of ammonia and ammonium nitrate plants.” The product is sold to the War Department and transfers made to us, and that accounts in part for that item I referred to originally of reimbursement.
Similarly, the synthetic rubber, carbide operation, is set out on pages 43 and 44. Also the work being done for the War Production Board, on the Pederson process, and other work for that Board, and mineral research, on page 44.
GULF COAST PHOSPHOROUS PLANT
I want to mention the Gulf coast phosphorous plant. This committee last year approved a recommendation, both the recommendation of the Chemical Warfare Service and certain agricultural representatives of the Federal Government, for beginning the construction of a plant on the Gulf coast for the production of concentrated phosphorous to be devoted initially to elemental phosphorous for chemical warfare. We have gone as far in the beginning of that project as we can without getting critical materials; that is to say, we have bought the site and have the design well along. There is some money in this budget for carrying that design forward. We are ready to start to build. We have been told by the Chemical Warfare Service that they are reconsidering the 1944 program and that we should stand by, and we are standing by, ready to go as soon as they find we should begin actual building.
The effort was to put into 1942 calendar year and early 1943 every bit of production that can be squeezed in for direct military requirements, that have to be had; and that accounts in part for the deferment of the Gulf coast plant in 1942.
We urge, therefore, that the funds be left in that reserve so that we can go forward with that project when critical materials become available.