E. J. UMBLIA
ESTONIAN OIL SHALE A N EMERGING INDUSTRIAL COMPLEX UNDER THE SOVIET SEVEN-YE-.I ontrol of the extensive oil-shale reserves in Estonia, together with the oil-shale processing industry based on these reserves, went into Russian hands in World War 11. During the first period of Soviet occupation (1945-1958), a crash program was instituted to relieve the critical fuel shortage in the northwestern region of the Soviet Union where reserves of other fuels are inadequate. For this reason rather high production costs have been tolerated. However, because much cheaper liquid and gaseous fuels have become available from southern Russia, this program in some respects has now become impractical. Therefore, to put the Estonian oil-shale industry on a more sound technical and economic basis, the Soviets are trying to develop an industrial complex capable of completely utilizing oil shale and its pyrolysis products. This complex is to consist of power plants, shale-pyrolysis plants, refineries, and building-material factories. A miniature model has been constructed and is said to be in trial operation. The complex is to be based on high productivity processing equipment, modern technological processes, and very large scale production, which according to optimistic estimates, will eventually involve an annual throughput up to 100 million tons of shale. According to the seven-year plan (1959-65), this will redwe the price of shale from underground mines to 28 rnhles ($7.00) and that from open pits to 16 to 22 rubles ($4.00 to $5.00 per ton). These costs differ sharply from those in the United States where oil shale can be mined for 50 cents per ton. T h e aspect of this program expected actually to put the industry on its feet is the extensive utilization of oil shale as a source of ch aw materials. The Soviets are trying to use, for a1 synthesis, materials such as olefins, aromatics, phenols, and neutral oxygen compounds which are recoverable from pyrolysis products. rials are plants, to be conarea of the Soviet Union, chemical fibers, synthetic c products. The planners
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believe that the kerochemical raw materials, produced in the industrial complex, can be competitive with those from usual petrochemical sources. However, improvements have been slow, and the entire program is said to lag increasingly behind general industrial progress in the USSR. Oil Shale Deporils
The richest and most abundant oil-shale reserves in northern Europe are .in northern Estonia where the deposits of oil shale (kukersite) are found in marly rocks of the middle-Ordovician period. At the northern border of the kukersite deposits, the shale beds lie rather near to the earth's surface, whereas to the south they reach to a depth of more than 300 feet. Total geological reserves are estimated at 14.5 billion tons. The pure kukersite contains up to 40% of bituminous organic matter (kerogen), 80% of which can be volatilized by pyrolysis. The average oil yield of kukersite is about 50 gallons per ton. The raw shale has a heating value of approximately 6400 B.t.u. per pound. Because of impurities, however, heating value ofcommercially mined kukersite is somewhat lower-Le., about 5500 B.t.u. per pound for pyrolysis-quality shale and 4500 to 4900 B.t.u. per pound for fuel-qual$ shale. In addition to the kukersite shales in northern Estonia, there are also rather wide-spread deposits of bituminous alum shale (dictyonema-shale). These latter deposits, as a ruk, lie deeper than the kukersite, but are fairly near to the earth's surface in some areas. This alum shale has a heating value of about 2000 B.t.u. per pound and an average oil yield of 16 gallons per ton. Reserves are estimated at about 15 billion tons. The bituminous alum shale cannot at present compete with kukersite shale. Future commercial utilization is considered to depend upon finding an economical &e for the mineral matter in the alum shale. This may be feasible, especially in areas where phosphorite-containing sedimentary rocks occur under the &-shale beds. An exploitation project at the Estonian Academy of Sciences is expected to be completed in 1962.
The Soviet Union's current sevenyear plan calls f o r a sharp increase in electrical power
from Estonian oil shale, plus greater utilization
,
%Explored Oil Shale Area %?$Unexplored Oil Shale Area
1
L ,
In the Present Seven-Yeor Plan, the State Budgel Provides for ConsiderableIndvstrial Expansion
Million Million Capital sum Rubles' B Oil-shale mining 690 172 Oil-shale processing 147 37 Heavy chemical developmentb 58 14 = C-&d at m @?&I mfb ej' 4 mblar pn dollm. flazcem, a?uol p w 6 A s i a g
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pawn of the mdla ir 5 lo IO timer lolua b
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Bos~dondolaoilondphorphorilr.
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Mining
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At present underground mines deliver 93% and the open pits 7% of the shale produced, but in 1965 these xfigures are expected to be 68 and 32%. Open-pit mining is employed in areas where the overburden to Known Ibe removed is not thicker than about 100 feet. reserves of this near-surface kukersite are several hundred The average output per miner in 1959 was 81.7 tons of oil shale per month at a direct cost of 35.1 rubles (58.77) per ton at the mine. Mining losses in the under-
AUTHOR ' E . J . Umblia was fmmerly associated with the Estonian oil shale industry and has systemntically collected and interpreted data from numerous Sooiet sources. At present he is
of shale-oil pyrolytic products as raw materials f o r the USSR chemical industry
ground mines amount to 450j00. The present quality of the mined shale is said to be poorer than under private management in the period of independence prior to Soviet domination. Through the use of new types of machinery and special room-and-pillar mining techniques, mechanization of the underground mines is to he raised from its present 18 to 90%. The efficiency of open-pit mining is similarly to he improved by installing new mining machinery. By these means, it is hoped to double or even treble the shale output per miner. At the same time efforts will be made to reduce mining losses from 45y0 to 25 or 30% in the underground mines, and to 13 to 20% in the open pits. But the successful application of such mechanized mining processes requires much more effective heneficiation of the mined shale. To accomplish this, a wetflotation method is said to be under development. Uses for Oil Shale
A tremendous increase in shale consumption for electric power generation is expected during the next few years. The shale-heated electric power plants in the oil-shale region are expected to deliver not less than 85% of the electric power output of 7.5 billion kw.-hr. planned for Estonia by 1965. T h e Baltic Thermal-Electric Power Plant at Soldino, for example, when fully completed, is planned to have a generator capacity of 600,000 kw. This plant will consume a large part of the normally difficult-to-use shale fines, which constitute about 25% of the total oil-shale output. The retorting capacity for oil shale is also to be increased from its present 3 million tons per year to about 4.3 million tons in 1965. The sbale-sas output wilt be simultaneously increased by 20% and shale-oil: production by 40%. SDR The remaining important oik-sale consumers are mainly industrial plants in Estonia, Latvia, Lithuania, and Russia. In accordance with the official commerci$P statistics, over 1.9 million tons of Estonian oil shale w j s exported to these countries in 1956. The largest RwVOL. 5 4
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sian consumer is the shale-gas plant a t Slantsy, USSR (near the Estonian frontier), w& an annual consumption of 0.8 to 1 million tons of kukersite. Apart from power plants, the biggest future Estonian consumer will be the portland cement plant at Kunda which, on completion of present expansion to an annual output of 600,000 tons of cement, will consume about 0.9 million ‘tons of oil shale annually. ,At present the whole shale-gas output and much of the oil is used for heating purposes. Thus by far the greatest part of mined oil shale both now and in the future will be used for power and heat generation. In 1956, 96% was so employed; in 1960, 90%; and by 1965, a t least 85% will still be used. Recently, however, there has been much concern as to whether oil shale, despite the announced price reductions, will be able to compete with cheap Russian petroleum fuel oil a t 70 to 90 rubles per ton ($3.00 to $3.75 per barrel) and natural gas a t 2 to 3 kopecks per million calories ($1.25 to $1.90 million B.t.u.). An exception may he the big electric power plants of the oil-shale district.
Shale Gar
In 1948 a shale-gas plant was erected a t Kohtla-Jaerve, which was claimed by the occupation authorities to be the biggest in the world of its kind. Since then, however, a shale-gas plant of comparable size has been built at the Russian shake-mining city of Slantsy. This plant also uses Estonian kukersite. Even after Anticipated Price Reductions, Shale Gar in the USSR I s Not Competitive with Natural Gas (Prtccr in kopeck/millzm col. and $/million B.t.u.)
Level of
Demand,.
over
Tons/yr.
25,000
8,00025,000
1 7 ($1 07) 7 3 ($4 601 4 7 ($2 9 6 )
2 9 ($1 82) 7 8 ($4 901 5 2 ( $ 3 28)
Price Natural gas Shale gas (19581 Shale gas (1965)
J k than 8,000
3 z ($2 02) 8 2 ($5 15) 5 6 ($3 5 2 )
By-products of the gasification process are gasoline, sulfur, polyphenols, tar oil, and shale coke. Up to now processing and purification of these by-products has been
Oil Shle in the United States-
Three leading companies and a government agency have this to say:
In this country commercial production of shale oil rests largely in a state of suspended animation, even though reserves are estimated to contain 10 times more oil than has been produced here to date. The major deposits are those of the Green River formation in Colorado, Utah, and Wyoming. Large portions of these shales will yield an average of ahout 25 to,30 gallons to the ton. These 25- to 30-gallon shales generally have been considered rich enough to be potentially feasible cohnnercially. Our shale oil production costs still are not considered competitive with petroleum, which now is in ample supply. An oil shale industry of significant and efficient size would require considerable lead time and a large capital outlay. In 1944, when oil supplies were a matter of grave concern, the Synthetic Liquid Fuels Act was passed. It authorized the Bureau of Mines program to carry out research and develapment and explore the feasibility of obtaining liquid fuels from oii,shale. Under this program the Bureau set up an engineering-scale operation near Rifle, Colo., for mining and retorting the oil shale and refining the shale oil. Projections based on the technology and cost data from these operations to produce gasoline, and Diesel and other fuels indicated that these products could be delivered and sold on the West Coast in a commercial enterprise plant at essentially the same prices as comparable petroleum products. However, the Bureau’s project was closed down and placed in standby about six years ag? before entirely conclusive results were obtained, At the present time th research on oil .shde.&sh+-..Th Laramie.&tm. le@ Resea@ Center, search areas cdnstitution a ns.of.&ale oil and kerogen, which is the major organic material in oil shale; and conversion of oil shale to crude oil and the crude into finished products. A consider44
INDUSTR,IAL A N D E N G I N E E R I N G C H E M I S T R Y
able program of continuing study also is being conducted on the oil shale resources of the entire nation. MARLING G. ANKENY Director, Bureau of Mims U.S. Department of thc h t n i o r
The Shell Oil Go. has studied extensively the refining of kerogen obtained from shale oil, and is confident that the technology now available is adequate for designing full-scale plants tomake fuels and lubricants. However, we believe that products from oil shale are not yet economically competitive with those from crude petroleum. Therefore we are continuing to study novel methods for obtaining crude shale oil from the ground, and have made substantial investments in oil shale properties in the Rocky Mountain States. This valuable natural resource of oil shale is of great potential importance to the welfare of the United States. H. GERSHINOWTZ President, Shell Deoelopment Co., Diu. of Shell Oil Co.
Believing that some day, shale oil will be needed to supplement our petroleum and natural gas, Standard Oil Co. of California holds large reserves of shale in Colorado. Both economic and political factors will probably play a part, but even under the most favorable conditions, shale cannot be expected to furnish a major part of our energy for many years to Eo= LwilLhaue ta PM fromscratclu‘na market which now requires over 16 million barrels of petroleum and natural gas per day, and which hy 1970 wll require 22 million barrels. Refining shale oil to furnish a complete line of products appears much further in the future than use of the oil with minimum refining or use in local situations where the economics are
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more favorable. In the most favorable of such situations, shale oil may become competitive with petroleum and natural gas in the 1970's. A. L. LYMAN President, California Research Carp. Studies conducted by the Union Oil Co. of California have centered primarily on retorting Colorado shale and refining the reSulting oil. We have designed and succedully operated a novel retort for long periods at a throughput of more than 1000 tom of shale per day. We have developed techniques for refiniug the crude shale oil to high quality fuels such as gasoline,. Diesel, and turbine fuels. These techniques have been confirmed in an acNd refinery mn. Union Oil now can engineer and aperate a technically sound and proved shale operation. Based. on our own mining, retorting, and refining data plus mining data from the Bureau of Mines, we believe that the minimum size installation for p m essing shale from the Mahogany Ledge in the Colorado deposit should produce at least 25,000 barrels of crude oil per day. Based on theeconomic consideration that shale oil should be refined near the retort site, producing and refining this amount of oil would need a capital mvestment of about $100 million. At this time, however, potential return on this investment is insufficient to justify the risk because:
4
I ~
f
< 3
-The market for oil products in the immediate vicinity of the shale rock is limited. Much of the production would have to be shipped to markets now supplied by petmleum which requires lower transportation cost.
,
..'! !
-Import quotas are uncertain and increased quantities of low-cost foreign oil could depress domestic prices. ~.
I t
I
-The p&ent depletion allow?nce of 15%; bked on value of the shale rock, is unrealistic.
w. E. BRADLEY Vice Prcsidcnf, Union Oil Co. of California
accomplished only to a limited extent. This togetker with poor efficiency of the gasification equipment itself, seems to contribute to the rather high price of the shale gas. Until 1953, the entire output was supplied to Leningrad via a 126-mile pipeline. Since the discovery of new Russian petroleum and natural gas reserves, however, Leningrad and other big cities are now changing to cheaper petroleum fuel oil and natural g&. Thaefore, plans have been changed in some respects. For example, the idea of installing new gas pipelines from Kohtla-Jaerve to Leningrad and the Lettish capital Riga has been abandoned, as well as that of a new shalegas plant at the Estonian shale-mining city of Ahtpe. Instead, new gas pipelines to Tallinn and certain citiesin the oil-shale district itself have been planned. These latter cities, at least provisionally, will be forced to con. sume the expensive shale-gas from Kohtla-Jaerve. I n the long run, however, it is believed that the problems of the Estonian oil-shale industry can be solved only by shifting to gas-chemical synthesis. I n fact, it is already being suggested that a big shale-gas chemical plant should be erected in the Estonian oil-shale district, for the purpose of producing large quantities of aromatics and phenols, which appear to be critically needed by the rapidly expanding Russian chemical industry. T h e same plant would naturally produce unsaturated hydrocarbons as well. Furthemiore; this gas-chemical pl&t might eventually be supplemented by a synthetic &monia plant.at a fai .Apart from various could produce raw materials in collaboration wit phosphate plants at Ma produce nitrogenous whole northwestern area of the Soviet Union. Planned VOL. 5 4
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outputs for Maardu plants in 1965 are about 500,000 tons of raw phosphoriie, 110,000 tons of sulfuric acid, and 160,000 tons of superphosphaFz. For chemical synthesis, however, the present shale gas would be a t least twice as expensive as natural gas. Also, its canten&o€&ired-ol~flG (ahout and bydrogen is too low. Although necessary experimental work on catalytic reforming of this gas to synthesis gas is said to have been completed, and the present gasification equipment being improved, there is little optimism about the prospects of basing economical synthesis-gas production upon the present gasification process. Instead, a change to fluidized retorting has recently been suggested. It is believed that a fairly cheap shale gas might be produced, containing over 35% olefins, and a sufficient amount of hydrogen to yield as much as 1 ton of synthetic ammonia from every 3 tons of shale. This is based on using fluidized-carbonization equipment of special design, with a solid refractory heat-carrier outside the shale bed, and a supplementary steam-carbon reaction. Also experiments are presently in progress concerning in situ carbonization of kukersite. Shale Oil
Reiortina of oil is uresentlv carried out in a t least 3 plants located at Kohtla-Jaerve, Kivioeli, and Kohtla. No information has been pub-
--
lished about the activities in a fourth plant at Sillamae. Formerly a small spa, Sillamae has now grown into an industrial city of several thousand inhabitants who, however, are kept isolated from-the remainder”of the countrg: Rumors of uranium recovery there can neither be confirmed nor denied. The plant a t Kohtla-Jaerve accounts for about two thirds of the whole shale-oil output. It is intended that, by 1965, oil output a t Kivioeli will be substantially increased, when the intended two tunnel ovens and a fluidized retort have been built. The plan to build a new oil plant a t the shale-mining city of Ahtme has now been rejected. The predominant types of retorts used for pyrolysis are tunnel and shaft kilns which are essentially the same as those used for pilot production during the period of Estonia’s independence. The technical quality of the full-scale retorts, however, is said to be in some respects inferior to those in the pilot plants. They have been sharply criticized because of their clumsiness, inefficiency, and inability to retort shale fines. The price of crude shale oil is 290 rubles per ton (Xll.00 per barrel). T o make shale-oil production economically sound, a radical improvement in retorting techniques seems necessary. Those who understand the problem have suggested turning to improved types of tunnel ovens, fluidized retorting, and carbonization in situ.
Oil Shale in Rest of World I
Information collected by I b EC editor of sources shows this pattern:
a wide variety
Except for some widely separated areas, economics of oil shale development throughout the world compares with that in the United States. Several European countries, Australia, and the Union of South Africa have operated on a commercial scale, but in most instances production has been either cut back or has ceased altogether. Spain, Brazil, Manchuria, and West Germany seem most active.
CHINA is thought to have the largest installation in the world. In 1915 during the Japanese occupation, an industry was started at Fushun in southern Manchuria, which now produces 9 to 12 million barrels of shale oil per year in Estoniantype retorts. The area has no oil and the shale which occurs as an overburden of coal can he mined at low cost. Also, a plant in the Kwantung Province near Hongkong may be producing some shale oil. C I 3 has a fairly vigorous industry; started about 1941, which vrocesses 900.000 tons of shale Der Year into 80.000 tons of products. There are no indications of production being cut back and products such as crude gasoline, ammbnium sulfate and nitrate, lubricants, solvents, paraffins, and gas oil are extracted. ~I
RAZ
is a promising area of development. In the sc-..iern sc ...oh fairly rich deposits occur which extend south into Uruguay, and @he USSR has indicated interest in develop46
INDUSTRIAL A 3 0 ENGINEERING CHEMISTRY
mental assistance. With some consultation with American engineering firmswhich used data obtained by the U. S. Bureau of Mines, a pilot plant was built at Taubatt, which is now operating on a semicommercial scale. If a commercial plant is built, it will he nearer the site of the deposits, and will be strongly subsidized by Petrobras, an agency of the Brazilian government. Financial backing by loan is being sought.
YUGOSLAVIA has oil shale deposits which occur in connection with coal, and some investigatory work on a pilot plant scale has been done. At one time it was planned to process some 15,000 tons of shale per day which was to be a by-product ofmining 1100 to 1200 tons of coal. Products such as benzene, gas oil, coke, and gas were to be produced. However, no commercial production has been reported, even though there are indications of revived interest. WEST GERMANY in May 1961, announced that a plant is operating at Dotternhausen. Organic material in the shale is burned as a fuel in the Lurgi process, and excess liberated heat is used to operate a power plant having a capacity of 40,000 kw.-hr. at 6000 volts. Richness of the deposits vary, but the shale is blended so that 7 tons is roughly equivalent in heat output to 1 ton of bituminous coal. The shale residue is used to make a cement clinker for producing a pozzolana-type cement. Capital investment for the installation was about $1.1 million. SWEDEN started a plant .in 1942 at Kvarntorp, which has processed some 3 million tons of oil shale per year. At the present time, most of the shale is treated by the Bergh-Kvamtorp method which utilizes energy from the shale only. How-
At present, pilot-plant scale investigations of fluidized retorting are said to be under way in two units. However, progress has been rather sluggish because of shortages in engineering equipment, measuring apparatus, installation materials, and other items. Shale-Oil Refining
Newly published.esthaam indieape t h a r i f d n : whore shale-oil output planned for 1965 is refined it might be possible to produce about 150,000 tons of gasoline (kukersol) and Diesel oil, 200,000 tons of impregnating oil and heavy fuel oil, 50,000 tons of asphalt, and 30,000 tons of phenols. T o date, however, only a minor part of the crude shale oil produced has been refined, the greater part being marketed as fuel. I n 1956, fol: example, deliveries to different areas of the Soviet Union amounted to over 200,000 tons (1.2 million barrels) of crude oil at 290 rubles per ton ($11.00 per barrel) and only 40,000 tons (240,000 barrels) of impregnating oil, a t 585 rubles per ton ($22 per barrel). Moreover, both the impregnating oil and the road asphalt produced are claimed to be of poor quality. According to the Estonian trade press, this state of affairs seems to have contributed considerably to the rather poor economy of the oil-shale industry. At the same time the outlook for marketing crude shale oil at the present price is obviously becoming smaller and smaller.
ever, some shale is processed by the Hultman-Gustahon method, and earlier the Industrimetoder and the Ljungstrom methods were used in situ The plant d e s fuel oil, gasoline, sulfur, bottled gas, ammonia, and lime, and has about 1145 employees. However, it is expected to close shortly.
SCOTLAND has an installation still operating in conjunction with a refinery at Pumpherston, but in recent years its output has declined steadily. For example, in 1945 it processed 800,000 barrels of shale oil, but in 1960 only about 420,000 barrels. The plant, owned by Scottish Oils, Ltd., comprises about one third of the total refinery capacity. UNION OF SOUTH AFRICA has extensive deposits, but no oil, and a plant owned by the Torhanite Mining and Refining Go wen1 on stream during the thirties. The products were blended with petroleum fractions. However, operation
was stopped in the middle fifties and the capacity was switched to coal processing.
Gar output by oplont in Kohlto-Jacroe. Until 7953,thc mtirr output mas piped to Leningrad. Now, hawcwr, thc Esronion capit.1 uses obout 20%
The development of refining processes has taken more time than expected. Not until recently has it been possible to modify all the small pilot units at Kuhtla-Jaerve and Kivioeli for the various refining stages which have been gradually developed, and to form them into two production-scale refining complexes. The larger of these at Kohtla-Jaerve, in addition to the recovery of refinery gases, is to produce primarily aromatics (from crude gas-plant gasoline), phenols (both from condensation water and shale oil), solvents, neutral oxygen compounds (from light oil), impregnating oil, asphalt products, petro!eum coke, and sulfur. Later, the production program may be extended to include certain additional processes at present still in the laboratory or early pilot stage, such as catalytic beneficiation of crude and heavy oil, hydrogenation of neutral oxygen compounds to cyclic compounds, production of flotation agents, pesticides, and synthetic tanning agents. The second refinery, at Kivioeli, will process crude gasoline from all the shale-oil plants. It is further planned to recover phenols, and to produce lubricating oils and basic materials for detergents from the light fractions of the shale oil. Later, a big plant for production of detergents for the whole northwestern area of Soviet Union is to be built at Kivioeli. Chemical Trends
SlAM at one time was processing shale at a site near the Burmese border, but activity now is probably dormant. AUSTRALIA has some of the richest deposits in the world, and in the past has operated a government-subsidized plant However, no commercial activity is reported now. USSR produces two thirds of her total output of shale oil in Estonia, but the balance originates within her own borders. About two nineths is produced near Leningrad, and one nineth in the Volga region.
Estonian technologists seem to think that, even after thorough overhaul, the shale-oil industry will not be able to compete with Russian petroleum and natural gas unless substantially converted to the production of petrochemical (kerochemical) basic materials. They emphasize that, since the kukersite-pyrolysis products are charac- . terized by rather high yields of olefins, aromatics, phenols, and neutral oxygen compounds, it is feasible t 4 produce a. number of basic materials valuable for org&id chemical synthesis in a simpler and possibly cheapd; VOL. 5 4 NO. 1
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way from shale gas and shale oil than from natural gas and petroleum. The Russian chemical industry, which under the current seven-year plan is to be vigorously expanded, is at present short of phenols and aromatics. This situation seems to be largely responsible for the decision of the Estonian Communist Party to direct the shale-oil industry toward chemical applications. One of the most important problems from the kerochemical viewpoint seems to be that of recovering well defined phenol fractions, usable for high quality chemical synthesis, from shale-pyrolysis products. The greatest success to date has been in recovering polyphenols from the condensation water of different pyrolysis processes. These polyphenols consist mainly of homologs of resorcinol. These can be used for making adhesives, synthetic tanning agents, and phenolic-molding compounds. The lower boiling phenols from the shale-oil fractions, with boiling point below 300" C., are regarded as still more valuable than the polyphenols. They may serve as basic materials for varnishes, phenolic resins, synthetic fibers, detergents, and adhesives, but the associated complicated processing problems are still far from being solved. Utilization of heavy oil-phenols is now being investigated at the laboratory stage. Preliminary results are said to indicate that the manufacture of epoxy resins and other quality products is likely to be possible only with very narrow fractions of these phenols. Among other kerochemical projects now under investigation, special emphasis is being placed upon the building of a carbamide-resin plant and a formaldehyde plant, as well as upon a pilot plant for manufacture of carbonic acids by catalytic oxidation of kerogen. Shale Coke and Ash
The spent shale (ash) from the retorting amounts to about 60Y0 of the kukersite. The weights composition of mineral matter in the kukersite is 38.3% CaO, 33.37, SiO2, 8.4% A1203, 6% F e 2 0 3 , 8.9% MgS04, 3.57, NazOfKzO, 0.1% S, and O.2yO C1. I n the past, shale coke and shale ash have been piled into huge stacks in the neighborhood of shale-oil retorting and shale power plants. By 1965, the planned shale processing capacity will yield over 2 million tons of coke from gas and oil plants and about 4 million tons of fly ash from shale-heated electric power plants. Such enormous quantities of coke and ash have always consituted problems in oil-shale processing, where the economics could be considerably improved by making use of these byproducts. Therefore, economical means of shale-ash utilization are being intensively sought in Estonia. At present minor amounts of shale semicoke from the shale-gas plant are used in the mineral-wool plant at Kohtla-Jaerve. The annual output of this plant is to be increased from the present 3000 tons to about 10,000 tons of mineral wool in 1965. Granulated shale coke has also been recommended as a suitable filler for the road asphalt made from heavy shale-oil fractions. Shale ash is used for manufacturing a hydraulic binder (kukermit) in two different grades. The poorer grade, 48
INDUSTRIAL AND ENGINEERING C H E M I S T R Y
known as ordinary kukermit, is made of ground shale ash from shale on the grate furnaces, with the possible addition of calcined clay. This grade is generally used for the manufacture of mortar. The better quality, called hydraulic kukermit, is made of fine-ground flyash from powdered shale power-plant furnaces. I t contains about CaO and lOy0a-CazSiOd. Hydraulic kukermit is used for manufacturing cellular concrete building blocks by a special foam preforming process. The material, however, is not as yet of reliable quality. The present annual output of kukermit, about 60,000 tons, is to be increased to 185,000 tons in 1965. Of this latter quantity, 120,000 tons of hydraulic kukermit will be used for making 500,000 cubic meters of cellular kukermit building blocks (corresponding to 230 million normal-size building bricks) at two large buildingmaterial factories located in the oil-shale district. Attempts to use hydraulic kukermit instead of cement or lime for stabilization of clayey road substrata have yielded promising results. Good stabilization, satisfactory for a first class asphalt-coated highway, has been obtained by using 56 pounds of hydraulic kukermit per square yard of road area. The resulting road is equivalent to that obtained when using 15 pounds of cement or 38 pounds of lime per square yard. Research and Technical Staff
For the utilization of oil shale as a chemical raw inaterial the processing methods and apparatus used in petroleum refining or coal carbonization cannot be applied. I n other words the development of a n oilshale processing industry depends very heavily on research. There are at present in Estonia about 10 institutes and special purpose laboratories engaged in oilshale research. This research work is coordinated by the newly established Institute for the Scientific Research of Oil-Shale Mining and Processing located at KohtlaJaerve. Some assistance is also obtained from related central research institutes in the Soviet Union. I n spite of these efforts, however, oil-shale processing research in Estonia is lagging behind the plans for industrial expansion. Complaints are constantly being mad? about the insufficient concentration of research teams upon the most urgent basic problems, and also about the disinterest of researchers in translating laboratory results into pilot-scale practice. There are also too few technologists with sufficient industrial experience in scale-up to large processing plants, and therefore many plants must be reconstructed several times before they fill the necessary requirements. Also, experienced polymer chemists are said to be very scarce. It is pertinent to note that people from different regions of the Soviet Union constitute the majority of the population in the industrial communities of the Estonian oil-shale district.
For readers interested in source material, the editors will be glad to supfily a list of references which are generally d@cult to obtain.
