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By Arthur Knapp

THE economics of fuel oil must be considered in two aspects; viz., fuel oil as one of a number of competitive fuels and fuel oil as a refined product of petroleum. "Fuel Oil" is usually defined as that product of petroleum which is used in furnaces for the generation of heat by simple combustion. It is true that any product of petroleum used in an internal combustion engine is essentially a fuel oil, but such oils are not included in the class known as "Fuel Oil." FUEL OIL AS ONE OF SEVERAL FUELS For a number of years, the petroleum industry has believed that the petroleum reserves were very limited and that petroleum products would begin to become scarce within a few years. The industry has believed FIG. 1.-DAILY AVERAGE CONSUMPTION OF FUELS BY PUBLIC UTILITY POWER PLANTS. that there would be a gradual but continual rise in prices as a result of this impending scarcity.

Jan 1, 1928

By Y. C. Liu, R. H. Richman

Deformation and recrystallization textures of the a solid solutions of Cu-P, Cu-As, and Cu-Sb alloys are examined as a function of composition. It is found that the deformation texture of copper is unckanged up to a composition of 0.43, 0.41, and 0.24 at. pct of phosphorus, arsenic, and antimony, respectzvely, and then the transition to the 70 : 30 brass type of deformation texture proceeds linearly as the logarithm of the solute content. Recrystallization textures consist of strong, new components that do not all bear the usual<111> rotational relation to the deformation components. The dependence of the deformation texture transitions and the recrystallization orientations upon composition and solute-element type is discussed. A systematic evolution of individual recrystallization components in the annealing texture of copper was portrayed as a function of germanium or tin content in a previous study.&apos; Similar patterns of tex-tural change have been observed with copper-zinc alloys,2 and in less detailed studies of other systems.3,4 In fact, most of the literature dealing with preferred orientations in copper alloys indicates that the influence of solute elements upon textures in copper is of one general type. As the alloy content of copper is increased, the deformation texture changes from the copper type to the 70:30 brass type, and the annealing texture undergoes a comparable change from the (001) [ loo] orientation of unalloyed copper to the {113} <211> type of 70:30 brass, with the notable exception of copper alloyed with Periodic Subgroup V-B elements.4-8 In almost every case it is possible to describe the reorientations after annealing as 30 to 40 deg rotations about <1ll> poles of the deformation components. Since there is apparently not much difference in the final textures of the copper binary systems already investigated, only a limited variety of preferred orientations has served as the basis for current theories of the origin of annealing textures. In order to test the validity of the proposed theories, and the possibility that the <111> rotations are not unique, it would be most desirable to study the reorientation relationships of additional, and heretofore unanalyzed, recrystallization components if such components exist. Examination of the literature reveals a good deal of uncertainty concerning preferred orientations in copper alloyed with elements in Subgroup V-B of the Periodic Table. Phosphorus is known to inhibit the cube texture in copper when present in amounts as low as 0.01 wt pct,8 but the recrystallized matrix that occurs instead of the cube orientation was reported as either random or weakly textured, with orientations not observed in Cu-Zn, Cu-Ge, or Cu-Sn alloys.4-9 A Cu-0.75 at. pct As alloy apparently contained, along with the (001)[100] and (113) <211> type of recrystallization components, {110} <112> and (110) <001> components, whereas an almost random distribution of orientations was found in alloys of higher arsenic content.4 A {110} <001> component also appeared in rolledand annealed Cu-Sb alloys, but otherwise the recrystallization textures of Cu-Sb alloys seem to con-

Jan 1, 1962

By Walter Kauenhowen

The production of crude oil in Germany during 1933 totaled about 1,669,521 bbl., a slight increase over the 1,608,558 bbl. produced in 1932. This is an extension of a yearly increase which has continued uninterruptedly since 1928. The 1933 increase in production is due chiefly to developments in the Nienhagen field. The production of the Wietze and Oberg fields remained rather stable, while the Oelheim-Eddesse and Volkenroda fields showed decreases. Nienhagen Field.—This field furnished about 61 per cent of the total German oil production in 1933. Most of the drilling activity centered the north district near the village of Nienhagen, where the trend of

Jan 1, 1934

By W. R. Shimer

In his valuable report on Finishing Temperatures and Properties of Rails,l Dr. G. X. Burgess, Chief of the Division of Metallurgy, U. S. Bureau of Standards, has begun a line of investigation which should be continued by those interested in the subject, and who have proper facilities for carrying out the work. For the past year or more the Bethlehem Steel Co. has been conducting experiments to learn the effect of rail finishing temperatures on their physical properties and microstructure and the results are here given for the consideration of those interested in the rail situation. Considerable differences of opinion have been expressed by various authorities, in the past, as to the effect of large or small grain size and high or low finishing temperatures of steel rails on their physical properties and wearing qualities. Low finishing temperatures and, therefore, low shrinkage, have been advocated on the theory that the wearing qualities would be improved. Others have recommended high finishing temperatures. The generally accepted cause for rail failures, due to the development of transverse fissures, is excessive wheel pressure on hard rails. One of the causes advanced for hard rails has been that they contain too high percentages of carbon and manganese; another that the rails were finished at too low a temperature, i.e., at or near the critical point. In the experiments herein described the rails were rolled from reheated blooms. All the rail blooms were charged hot in a reheating furnace and brought up to about the original ingot-rolling temperature before rolling into rails. These rails gave better results in deflection, withstood a greater number of drops before breaking, and showed greater ductility than rails of identically the same composition and section which were rolled direct from the ingot. Rails rolled from reheated blooms, finished at somewhat higher temperatures than when rolled direct from the ingot, have a different microstructure, which the writer does not believe is due so much to the difference in finishing temperatures, as to the difference in

Jan 1, 1915

By C. R. Boyd

This section is about fifty miles in length, extending from the semi-magnetic and brown iron-ore deposits, near South Fork of Holston River, on Virginia and Tennessee State line, through Bristol, Tenn., Goodson, Imboden, or Mineral City, and Big Stone Gap, Va., to the Cumberland Mountain, on the line between Virginia and Kentucky. Following a geological section from the southeast for near South Holston River), to the northwest, we encounter, first: The slates of No. III.,* generally dipping southeasterly with a trend of N. 65&apos; E. They ontcrop along the north bank of South Holston River, having a thickness of 375 feet, 260 feet of which, as at Pen Rhyn quarry and the James quarry, southeast of Bristol, is slate of high grade for interior architectural uses. Next northwest is an undulating series, giving surface-exhibits of these slates, alternating with Trenton limestone, for 21/2 miles, to the&apos; line of semi-magnetic red iron-ores and brown iron-ores, of the upper horizon of No. II., generally pitching southeasterly, as though the whole series, including the slate described, formed a great trough, with its middle

Jan 1, 1887

By W. R. Shimer

IN his valuable report on Finishing Temperatures and Properties of Rails, I Dr. G. K. Burgess, Chief of the Division of Metallurgy, U. S. Bureau of Standards, has begun a line of investigation which should be continued by those interested in the subject, and who have proper facilities for carrying put the work. For the past year or more the Bethlehem Steel Co. has been conducting experiments to learn the effect of rail finishing temperatures on their physical properties and microstructure and the results are here given for the consideration of those interested in the rail situation. . Considerable differences of opinion have been expressed by various authorities, in the past, as to the effect of large or small grain size and high or low finishing temperatures of steel rails on their physical properties and wearing qualities. Low finishing temperatures and, therefore, low shrinkage, have been advocated on the theory that the wearing qualities would be improved. Others have recommended high finishing temperatures. The generally accepted cause for rail failures, due to the development ,of transverse fissures, is excessive wheel pressure on hard rails. One of the causes advanced for hard rails has been that they contain too high per centages of carbon and manganese; another that the rails were finished at too low a temperature, i.e., at or near the critical point. In the experiments herein described the rails were rolled from reheated blooms. All the rail blooms were charged hot in a reheating furnace and brought up to about the original ingot-rolling temperature before rolling into rails. These rails gave better results in deflection, withstood a greater number of drops before breaking, and showed greater ductility, than. rails of identically the same composition and section which were rolled, direct from the ingot. Rails rolled from reheated blooms, finished at somewhat higher temperatures than when rolled direct from the ingot, have a different microstructure, which the writer does not believe is due so much to the difference in finishing temperatures, as to the difference in

Jan 3, 1915

By Clifford Frondel

THE aluminum oxide known as corundum has several varieties that have been used as gem materials since ancient times. These include the red variety called ruby, the blue variety sapphire, and the asteriated types of ruby and sapphire. Asteriated sapphire was known to the ancients under the name of astrios, and descriptions of this gem were given by Pliny and other early writers. The relation of these gem materials to each other as varieties of a single species, corundum, was first clearly established by Haüy in 1805 and J. M. Güthe&apos; in 1809. Natural gem corundum is obtained principally in Ceylon, Siam, Burma, India, and Australia. Star sapphires and rubies always have been highly prized and in recent years have become particu- larly popular in the United States. Natural star rubies of large size and fine quality are extremely rare and rank with large and fine emeralds and diamonds as the most valuable of gem stones. Interest thus attaches to the recent success in commercially synthesizing star sapphires and rubies of a size and perfection unmatched by nature. Corundum was first synthesized as crystals in 1837 by A. Gaudin, who fused alum and aluminum oxide with potassium sulphate. Numerous other syntheses have been reported in more recent years. Summaries of this work are given in Doelter&apos;s Hand-buch der Mineralchemie, Mellor&apos;s Compreheizsive Treatise of Inorganic Chemistry, and other reference works. The methods employed include the reaction in the gaseous state at high temperatures of halogen compounds of aluminum with water vapor or boric oxide; the crystallization of aluminum oxide from fusion in potassium molybdate, potassium dichrom-ate or borax; and crystallization from highly aluminous silicate melts. Red, blue, or green colored varieties can be obtained by the addition of small

Jan 1, 1955

By F. E. Griffith

Several disastrous and a great number of near-disastrous mine fires have been started by igniting the combustible conductor insulation and outer covering of trailing cables. Those who have had experience in fighting such fires know that they are extremely difficult to combat and extinguish owing to the irritating and noxious gases, fumes and vapors evolved from evaporation, distillation and combustion of the sundry compounds used in the construction of cables. When electric-motor-driven coal-cutting machines were first introduced in coal mines, the electricity was transmitted to the apparatus by two single-conductor trailing cables. Later, two-conductor parallel and concentric types were developed. These early cables were made with the materials available at that time with relatively little thought given to using new materials or utilizing the old to the best advantage. The copper conductors were stranded to give flexibility, but there were too few strands and the method of laying them was such that they did not endure well the stresses of twisting and pulling, to which trailing cables used in mines are usually subjected. The rubber insulating compounds used were not satisfactory in resisting water, high temperature, and the crushing stresses encountered in mine service. The outer coverings were cotton or jute braids saturated with tars or asphalts having relatively no abrasive resistance. In fact, the only consideration given to trailing cable design because of its extremely short life, was to construct it at the lowest possible cost. With increased electrification and mechanization, more serious problems were encountered. Cables used in mines were exposed to more severe conditions than in any other industry. The excessive overload currents, poor heat dissipation, severe abrasion, crushing loads from falling material, runovers, and any of the other things that tend to destroy cable, called for vast improvement in trailing cable design for mine use. About 1918, one manufacturer who recognized the need for improving the toughness of cables in order to obtain greater safety and longer life, developed a special rope-stranded conductor, a superior rubber insulation compound and a tough rubber sheath or jacket compound. As a result of this type of construction, broken conductor strands were practically eliminated, the insulating material withstood high temperature without undue disintegration, and the jacket, similar to that used for automobile tire tread, had high abrasion resistance, high tear resistance, and was waterproof. While the initial cost of these cables was higher than the jute-filled braided types, this disadvantage was more than offset by increased safety and longer service. Cables with these improved characteristics were first installed in mines in 1920. Since 1930, the use of braided trailing cables in coal mines has been almost completely supplanted by the more superior types, employing high-grade rubber compounds for insulation and sheath. The next steps taken to improve the

Jan 1, 1949

By Malcolm V. Lowry

At Balmat in northern New York State, the St. Joseph Lead Co.&apos;s 2100-tpd zinc mining and milling operation is utilizing a unique thickener in conjunction with conventional crushing, grinding and flotation methods. From 1930 through 1962, zinc concentrates went directly from flotation to the filtering, drying and loading facilities, all of which had to operate 24 hr per day. Wide fluctuations in tonnage also had to be accommodated due to variations in the grade of ore. Many problems were thus encountered in filtering and drying, but the cost of installing a conventional, large diameter thickener could never be justified. In 1963, after thorough investigation, an unconventional thickener that is unusual in several respects was installed at Balmat. The tank depth is 16 ft instead of the normal 8 ft. The rakes are raised and lowered by having the main drive gear located on a movable platform. Automatic controls are programmed to raise the drive platform and rakes during one shift of storage. During the next two shifts of withdrawal, the controls are programmed to lower the drive platform and rakes.

Jan 5, 1966

By L. C. Graton

THE Federal taxes on incomes and excess profits are of course heavy. In 1917, the value of the mineral production of the United States was a little in excess of $5,000,000,000. The total of Federal taxes for that year, for the mineral producing companies, as computed by themselves, amounts, according to tentative compilations, to about $207,000,000, and the total for the comprehensive group of mineral and metal indus-tries to about $766,000,000, which figures represent respectively 9.5 per cent. and 35.1 per cent. of the total tax paid by all corporations. Be-cause of greater complexities in applying the revenue laws to mineral properties than to most other industries, opportunity is afforded for wide differences of view. The taxes indicated above, therefore, are not final

Jan 11, 1919

By David E. Fogelson, James J. Olson

Rock mechanics as a guide to a safe underground operation is gaining importance as more is under- stood of rock behavior under stress and of the competency of rock after blasting. The U. S. Bureau of Mines&apos; Twin Cities Mining Research Center and White Pine Copper Co. personnel undertook a joint research program recently to define how the rock adjacent to a newly opened underground working could be left as undisturbed as possible. The goal was to leave a competent structure which would tend to limit rock falls and thus decrease the incidence of fatalities from this greatest of all underground hazards. High-amplitude stress waves and borehole gases create a crushed zone in the rock, the thickness of which is about equal to the borehole radius. Beyond the crushed zone, additional structural damage occurs to the rock from the microstructural level up to visible fractures that may extend several feet. This type of rock damage near the final excavation lines reduces rock strength and increases the possibility of failure of the openings from subsequent vibrations or stresses.

Jan 9, 1969

By Walter Renton Ingalls

In addition to the localities in which tin-ores have been found in Mexico, mentioned in my paper on the a Tin-Deposits of Durango," presented to the Institute in March, 1895,* the following should be recorded. I am indebted to Captain Henry Freeman, of Durango, for the notes as to these occurrences. In the Sierra de la Candela, west of the Sierra de Sail Frailcisco and El Promontorio (the Llano de Guatimape intervening between the two ranges), cassiterite is found in veins and stream-beds. The veins are narrow, and the ores have the same characteristics as those of Potrillos. They were exploited by miners from Coneto in 1882-86, the more extensive work having been done on the northern side of the mountains. In the Sierra de las Palomas, on the western edge of the Otinapa, ranch, about 25 miles W.N.W. from the Diablo mine in the Cacaria district, there are several small veins, of which the ore, gangue and country-rock are similar to those of the Cerro de los Remedios, near the city of Durango. The latter are essentially the same as the Potrillos veins. In the Cerritos del Olote, in the Murphy grant, about 50 miles W.S.W. from Durango, there are old mines, now partially filled. The veins are narrow and poor; the ore is highly ferruginous; the country-rock is rhyolite, with some granite; immense quantities of chalcedonic rubbish are strewn along the course of the veins. In the Cerro Blanco, overlooking the pueblo of Mezquital, 48 miles south of Durango, tin-ore is mined by the natives.

Jan 1, 1898

By Robert C. Beckstorm

Russia produced over one-half of the world&apos;s petroleum in 1901. It dropped to a low figure in 1920 during the reorganization of the new government. Since then it has had a remarkable growth under the constant demands from the Central Bureau at Moscow. The five-year plan called for the development of all industries, many of which had permitted their equipment to gat out of repair or become obsolete, so that when the magic wand of authority demanded that they double, triple or quadruple their former production they looked to the oil industry for aid. This plan made necessary the building of new factories, dams and power stations; the developing of mines and agriculture, and in many places the building of cities and railroads. Exports were the solution and petroleum was the logical one to carry the load of development of the more backward industries. It had a ready market and fields located advantageously for transportation, which was cheap, and there was sufficient oil to meet the market demands at that time, as domestic consumption was not great. The building program demanded new and modern machinery and technical aid from abroad. FIG . 1.-PETROLEUM Money was necessary and petroleum was the impor- 1925-1931. PRODUTION IN RUSSIA tant product of exchange. This accounts for the rapid development of the old fields, the search for new ones and the building of refineries and transportation facilities. Fig. 1 shows the advance in production since 1925. There has been a. steady increase since 1920, and with the improved drilling equipment and improved methods it will increase as long as the now proved fields continue to produce new wells. The fields of Baku and Grozny have yielded 95 per cent of this production. The Cara Chukur field, which is being developed at the present time, is an extension of the Surakany at Baku and may be considered a part of the old field. New fields are being

Jan 1, 1932

By C. van der Poel

When oil is displaced from a horizontal formation by another fluid of lower density, the latter tends to override the former in the shape of a tongue owing to gravity segregation. This gravity tongue has an adverse influence on the oil recovery. If the fluids are miscible, diffusion (mixing) takes place at the interfacial boundary of the gravity tongue. This mixing should have a favorable effect on oil recovery. The report describes a laboratory study of the magnitude of the mixing zone under various conditions, so as to assess the effect of diffusion on oil recovery both in laboratory experiments and under actual field conditions. The technique used enables visual observation and measurement of the size of the mixing zone in transparent glass-powder packs. The results show that in experiments in small models and cores the width of the mixing zone may well be of the same order of magnitude as the height of the model. In such cases oil recovery is favorably affected by mixing. It can further be concluded that, under conditions prevailing in the field, mixing of the injected fluid with reservoir oil is equal to that caused by molecular diffusion alone, eddy-mixing not taking place to any appreciable extent. A simple calculation, then, shows that molecular diffusion is too small for a beneficial effect to be expected from the injection of miscible fluids in horizontal or nearly horizontal reservoirs unless pay zones are thin. INTRODUCTION This paper gives results of experiments made on the mixing which occurs when a miscible displacement is carried out in a horizontal reservoir. This mixing takes place at the interfacial boundary of the gravity tongue formed when the lighter injected fluid overrides the oil present in the reservoir. The object of the experiments was to simulate the field case where, for example, propane with a viscosity of 0.075 cp under reservoir conditions displaces an oil of viscosity 0.6 cp. In the experiments the lighter fluid had a viscosity of about 1 cp and the heavier one a viscosity of about 8 cp, so as to obtain the same viscosity ratio. In order to enable the results to be compared with those published in the literature, a set of experiments with viscosity ratio equal to one was also performed. EXPERIMENTAL TECHNIQUE The technique developed for the purpose enables the width of the mixing zone to be studied as a function of time and place. A glass-powder pack is saturated with a water-glycerine mixture of suitable viscosity, which represents the reservoir fluid. The pack is then rendered transparent by dissolving sufficient ammonium thiocyanate in the mixture to obtain a solution with a refractive index matching that of the glass powder. Alkaline water to which phenol-phthalein has been added is used as the lighter and less-viscous displacing fluid. In those places where mixing or diffusion of the two liquids occurs, the slightly acidic ammonium-thiocyanate solution neutralizes the alkali in the water, and the glass pack shows up white against the red-colored invading water. If a black cloth is hung over the back of the apparatus, the transparent part of the glass pack appears black. In this way the position of the two phases and the transition zone between them is clearly visible, as shown in Fig. 1 (where the red-colored invading water is the grey-shaded zone lying uppermost). In all experiments the amount of alkali in the water was chosen such that the upper contour corresponded to a concentration of 5 per cent of the dense liquid. The lower contour is determined by the size of the glass grains and the thickness of the pack and, consequently, varies from experiment to experiment. Corresponding concentrations of the dense liquid range from about 97 per cent for packs of small grain size (permeability = 1 darcy) to about 95 per cent for those with large grains

By Anthony Folger, Charles E. Straub

Kansas produced 38,150,878 bbl. of oil in 1928 and 40,658,170 bbl. in 1929, thereby retaining its rank as fourth among the oil-producing states of this country. Production for 1928 was less than that for 1927 (Fig. 1) because of a decrease in the number of completions, but the average initial production per well (Table 1) shows an increase due to the completion of wells of comparatively large capacity in the new Valley Center pool of Sedgwick County. This increase in average initial production per well was further augmented during 1929 by completion of additional wells of comparatively large capacity in the Valley Center pool and the new Greenwich pool of Sedgwick County. Production for 1929 exceeded that for 1928 and threatened to exceed all records except that of 1918, however, production was prorated in

Jan 1, 1930

By Dean F. Winchester, C. D. Johnson

The so-called Rocky Mountain region is here made to include Colorado, Idaho, Montana, northern New Mexico, Utah and Wyoming, an area of great distances and relatively sparse population. Conditions of distance, transportation and markets have had their retarding influence on devolopment and production but the increase in facilities and markets in recent years has provided additional incentive for more thorough search for new productive areas and the more complete development of the known fields. The low prices of crude during the past year have offset, to a certain extent, the desire for increased production and much of the effort has been directed therefore to outlining new areas rather than to attempts to increase production from known fields and thereby add to the already sufficient supply above ground. During the year just closed the Rocky Mountain region has seen consistent efforts to outline new areas and these efforts have been reasonably successful. In this area a very large part of the land is government property, and by cooperation between the government, the private owner and the company it has been possible to carry on development in a scientific manner, providing for the maximum recovery of valuable products at least cost and at times when prices were best. Due to the fact that in the Rocky Mountain region costs of exploration and development are relatively high because of natural circumstances, it has been the policy of operators to drill test wells only on structures where they controlled a large proportion of the land. Even community lease programs have been effected in certain areas, thus obviating the necessity of offset drilling and the attendant uneconomical and even wasteful production. Oil production in the Rocky Mountain states has shown a slight increase during the year, the average daily production for November being 78,124 bbl. as against an average in January of 76,681 bbl. The total production during the first 11 months of the year, according to the U. S. Burcau of Mines, was as follows:

Jan 1, 1929

By R. W. Parsons, P. R. Chaney

Oil recovery by the imbibition mechanism can be important in fractured carbonate reservoirs with a bottom water drive. Laboratory experiments were performed on water-wet carbonate rocks to model this process. The results are interpreted in light of the applicable scaling laws. The imbibition production behavior of a pillar of rock subjected to a slowly rising water table can be synthesized from data on total immersion experiments on small rock samples. If the rate of water table rise is slow enough and if the physical properties are such that the imbibition zone is of a small vertical extent, then only the final oil recovery on the small samples need be known. Applying laboratory imbibition data to a real reservoir should be done with caution because of possible wettability problems and the unknown behavior of two-phase flow in fractures. INTRODUCTION The spontaneous taking up of a preferential wetting fluid into a porous medium with the simultaneous expulsion of the contained fluid is termed imbibition. One of the many physical imbibition processes is the production of oil by the taking up of water into a water-wet reservoir rock. In certain types of heterogeneous reservoirs, e.g., fractured, it is realized that imbibition alone may be the dominant mechanism. Theoretical studies of imbibition oil recovery have followed several lines of attack. The behavior of certain mathematically tractable and conceptually simple models have been analyzed. Birks1 considered a bundle of vertical capillaries model, while Perotti et al.2 and Kelemen3 used a model of a series of vertically oriented fractures. If the oil production behavior from a block of reservoir rock is known, then the cumulative behavior of a vertical stack of these blocks subjected to a rising water table can be determined by a method outlined by Aronofsky et al. 4 Knowing the capillary pressure and relative permeability functions should uniquely set the imbibition behavior for a given sample. Solutions of the partial differential equations describing the process, however, present some formidable problems. Digital computer techniques have been applied to displacement processes in which the capillary pressure has been included.5"8 More recently, similar techniques have been used by Blair 9 to calculate countercurrent imbibition behavior. The fact that imbibition behavior is described by the usual fluid flow equations (Darcy&apos;s Law and continuity equation) implies that the derived scaling laws should apply equally to this situation. Use of model experiments to study imbibition has been employed by Graham and Richardson 10 and Mattax and Kyte,11 who actually tested the scaling law applicability. This study is concerned with scaled model imbibition experiments on water-wet carbonate rocks. Of particular interest is the slowly rising water table experiment. This simulates a highly fractured reservoir with the water table rising uniformly through the vertical fracture system. Experiments were performed on different sized samples and with different rates of rise of the water-oil interface surrounding the rock pillar. Total immersion imbibition experiments on smaller rock samples were performed to test the basic linear scaling laws and to see if these simpler tests could be used to synthesize the rising water table experimental results. THEORY IMBIBITION SCALING LAWS Scaling laws for the flow of two incompressible immiscible fluids in a porous medium have been presented by Rapoport.12 These are derived directly from Darcy&apos;s Law for the individual phases and the continuity equation. Results from a laboratory model experiment will duplicate those from some reservoir prototype if a constant proportion is maintained among the three forces acting on the fluids — the capillary pressure gradient, the gravitational gradient and the flowing pressure gradient. Operation of the model (i.e., fluid injection or withdrawal) must be conducted in accordance with specific equations. If the

Jan 1, 1967

By J. Szekely

The paper discusses simultaneous heat conduction and diffusion. These problems may arise in slag-metal kinetics and in connection with rapid heating or cooling of specimens. A mathematical formulation is given and it is shown that the transients due to either the variability of the diffusion coefficient with temperature, or thermal diffusion, are unlikely to be important for molten or solid metals and slags. The negligibility of these effects is due to the large values of the ratio thermal diffu-sivity/molecular diffusivity. In many problems relating to transport-controlled metallurgical kinetics the diffusion process is accompanied by the transfer of heat; large-scale metal refining or metal reduction may be quoted as examples. It has been shown that due to turbulent mixing in these systems the relevant transport phe- nomena are best described in terms of "surface renewal models" which require the solution of the unsteady-state diffusion equation.1-1 Problems involving simultaneous diffusion and heat conduction are also encountered in the laboratory in connection with rapid heating or cooling of specimens. The effect of variable temperature on diffusion may be twofold: a) in the absence of "cross effects" the problem, due to variable temperature, is that of diffusion with a variable diffusion coefficient; b) if the Soret Effect is nonzero, thermal diffusion must also be taken into account in the formulation. Although information is available on thermal-diffusion transients in a steady-temperature gradient,4&apos;5 little work has been done on the effect of unsteady temperatures on either the diffusion coefficient or on thermal diffusion.&apos; In the following a formulation is given and solutions presented with a view of examining the areas where these effects may be important.

Jan 1, 1965

By Earl Oliver

Some two years ago the Petroleum Division of the A. I. M. E. organized a special study of unit operation. That method of handling oil pools had been urged as the remedy that would save the United States petroleum industry from the crisis that even then loomed as more than a small cloud on the horizon. Today it is only one of several remedies vigorously advocated. Proration, regulation of imports, unit operation, constructive marketing and interstate compacts all have their earnest proponents, but the advocates of each have been disposed to look with indifference on the other respective proposals, with the result that none has had united support. Meanwhile the industry has drifted rapidly toward a serious crisis, the imminence of which in itself may bring the solution. The gravity of the situation tends to force study of the merits of proposals that a short time previously were brushed aside as impractical; and to the surprise of most of us we now find merit where previously we thought none existed. Irrespective of what might have been the result had any single proposal being adopted years ago, it is now apparent that under present conditions no one of the remedies—unit operation, proration, regulation of imports or constructive marketing—standing alone would be of much benefit. On the other hand, it is becoming evident that a well balanced program comprising all four of these remedies might save the United States petroleum industry; also that some such comprehensive program might be necessary to save it. It is even becoming evident that the despised interstate compact might be an appropriate type of machinery in which to group and coordinate all these remedies. We have progressed beyond the belief that either the industry or the government working alone can correct the situation, and have arrived at the more healthy realization that the task will require most sympathetic cooperation between government and industry, backed by an equally sympathetic public understanding. If we were functioning under a Mussolini or a Stalin, stabilizing the petroleum industry would be a much simpler task. However, in the

Jan 1, 1931

By G. A. Vissac, R. G. Minet, N. E. Sylvander

R. G. Minet—The authors&apos; description of the remarkable progress made in the last few years in applying the fluidized solids technique to the problem of lignite drying and carbonization clearly demonstrates that engineering techniques available today may make many processes practical and profitable which a few years ago were considered otherwise. As pointed out in the article, the future of the carbonization step hinges on the value and utilization of low temperature tar. On paper, at any rate, this tar looks like a valuable raw material for the chemical industry to use. Some 50 to 60 pct may be converted to pitch for electrodes, roofing, road tars, and other valuable products; the 25 to 30 pct tar acids could conceivably form a basis for a new low cost resin or plastic of the phenolformalde-hyde type. Yet these materials are so new and dissimilar from available sources that much work must be undertaken by the chemical industry before they will be accepted. Now that the work of Dr. Perry and his colleagues has made a large supply of low temperature tar a real possibility, I would expect the chemical industry to accelerate its work in this field. On the basis of certain data available in the literature it appears possible to produce a more aromatic tar, although in smaller yield, by operating at temperatures in the range of 1300" to 1500°F. Operating a fluidized bed process for lignite at these conditions should be technically possible, at least, and could produce a tar having more familiar characteristics. I wonder if Dr. Parry would care to comment on such a possibility. Incidentally, in our own work on carbonizing coking coals in fluidized beds, using Ohio, Pennsylvania, and West Virginia high volatile bituminous coals, we have obtained yields which agree with the correlation given for tar yields vs moisture and ash-free volatile Btu. Our data are slightly under the line, but certainly in the range of the correlation. We have also obtained evidence in support of the authors&apos; statement as to the effect of air on the process. In our pilot plant all the heat required for carbonizing is released by internal combustion of char in the fluidized bed in normal operation. We are also equipped to obtain all carbonization heat by external electric heaters on the shell of the carbonizer while introducing only an inert gas to the process. We note no difference in tar yield or characteristics between the two operations. In the case of the gas, however, it appears that some hydrogen is consumed by the air combustion. We would be interested in hearing in a little more detail about the hot dust and char handling problems at Sandow. Have the authors found char subject to spontaneous combustion? Have they ever tried a coking coal in their pilot plant? V. F. Parry (author&apos;s reply)—Production of a more aromatic tar by operation of the carbonizer at 1300" to 1500°F does not appear to be economical. 1) The capacity of a reactor operating at 1500°F would be 30 to 50 pct less than the capacity at 932 °F and the cost of processing would increase materially. 2) The cracking of tar vapors in a reactor requires appreciable time to complete the reactions and it is doubtful that considering the very short time of residence of tar vapors within the reactor (4 to 10 sec after evolution) the basic character of the tar would be changed significantly. This is indicated from the data reported in Table XIV. 3) General studies have shown that it is advisable to operate at the minimum temperature to produce the maximum tar and minimum gas. 4) Operating problems and the maintenance of vessels and reactors, and the hazards of handling hot char, increase with the temperature of carbonization. It is technically possible to operate at temperatures as high as 1500°F, but in my opinion it is not economical or desirable. We believe that the primary tar must be won in the simplest way and then processed alone to change its character for production of desired products. It is interesting to have confirmation of our observations on the reaction of air with the products of carbonization. The major reaction is with the char, fol-

Jan 1, 1957