US1390230A - Method of transporting carbonaceous substance - Google Patents

Description

LINDON WALLACE BATES OF MOUNT LEBANON, NEW YORK,

METHOD OF TRANSPOBTING CARBONACEOUS SUBSTANCE.

No Drawing.

liquid carrier. More specifically it pertains to the transportation of pulverized coal, coke, or other solidcarbonaceous substance through pipes by means of an oil carrier, or other liquid hydrocarbon carrier, in which the particles are artificially stabilized to enable the passage of the composite throu h the pipes without congesting the same. t also refers to the method ofadapting the carrier for such service. The word solid is used in contradistinction with liquid and gaseous. It does not refer to size, inasmuch as the material to be carried is reduced to a small size and may be partially dissolved or peptized in the carrier. By the word stability there is meant non-separation of the components for a given period of time, such as will enable the carriage of theparticles through pipes by the carrier. It does not mean permanent stability, nor simply slow sedimentation which proceeds naturally; It means the retardation of separation by artificial means of the particles, especially those above colloidal size, since those within colloidal limits are naturally stable to ahigh de ree.

oal may be taken as a typical example of the solids it is proposed to transport. At the present",time this mineral is conveyed from the coal fields to market chiefly over railroads and in vessels. The cost of so doing, however, is becoming more and more expensive. On the other hand, the transportation of oil long distances through pipes has been carefully developed and perfected in recent years. Attempts have been made to carry or force coal. through pipes by means of water, butv owing to rapid sed1- Q mentation it has been possible to convey as a maximum only about 20% by weight of particles under a considerable head of water traveling some twenty feet per second. Save under such exceptional circumstances or in rivers, water has not served as a carrier to Specification of Letters latent.

Patented Sept. 6, 31921.

Application filed December 3, 1919. Serial No. 342,263.

transport coal. Only very small amounts may be made into a colloid with water, and so made naturally stable for transportation. So too pulverized coal is carried short distances through pipes by means of air under pressure, and also with the aid of a vacuum. But for economic reasons it is necessary to provide a method for carrying larger quantities of coal long distances through pipe line. The ability to pipe coal to market is of importance to the prosperity of localities situated far from the coal deposits.

By combining high percentages of pulverized coal with oil in such a fashion as to form a composite stable for the period of transportation, the composite like oil may be pumped or caused to flow considerable distances through pipes. In order to convey coal or other solids of a carbonaceous character through pipes with the aid of an oil or similar liquid carrier, it is necessary to reduce the solid by pulverization or otherwise so that about 95% passes through a hundred mesh per inch screen and 85% through'a two hundred mesh screen. Finer subdivision is desirable but is not essential. Such particles are far above colloidal size. The fineness desired depends to a certain extent upon the specific gravity of the solid and of the liquid, and upon the nature of the carrier and composite. It is possible to convey even coarser particles through pipes in the manner indicated because of the motion of the carrier in the pipes. There is not only the forward movement of the liquid, but there is a' tumbling motion and currents of all sorts due to natural or specially introduced unevennesses in the pipes, bends, elevations,

substance having stabilizing qualities. Of.

the substances which may be used to adapt the carrier to the proposed service one may mention mineral soaps, of which a soap comprising lime and rosin, or'like or equivalent acids or alkali, is preferred. Such an amount of this fixateur which adds from to 1%% of rosin to the total composite of carried and carrier will give a stability which may be varied in degree and duration and which may be caused to endure for days weeks or months. Another class of stabilizing substances, having for certain coals a peptizing effect, is that of coal derivatives, such a creosote, naphthalene, and water gas tar. The percentage required of the latter class of substances varies between 5% and 20%, also byweight. It is likewise possible to stabilize'coal and other particles -in oil as a carrier by adding from 10% to 30% by weight of a liquid combustible immiscible with the carrier, such as tar in oil. These methods are not equally effective or applicable, and one may combine them or some of them to advantage when the transportation of particles through pipes and use of the product is concerned. When the liquid carrier is composed of two or more different 1 liquid hydrocarbons it is found that a is superior as a carriersto a single liquid hydrocarbon. This may be explained by the fact that densification is more easily broken up by agitiation in the case of such a composite carrier.

The particles may be combined with the carrier either before, during or after the fixation of the latter. The combination treatment consists in blending the components by means of mechanical agitation or heat treatment or both, preferablythe latter 'method. The same commingling treatment may be used to fixate the carrier as to blend the carrier with the particles. The heat treatment consists in heating the mixture for at a temperature of from 65 C. to 95 C. The mechanical blending consists in passing'the components simultaneously through a coalpulverizing mill, paint mill, or other mixing apparatus of this sort.

A few minutes of such I treatment usually sufiices. When heat and mechanical blending are combined, the heat need not be applied so long as if it were used alone. The combined heat and mechanical treatment, maysuccessively or alternately. The components may be combined in batches or in a continuous process.

All li uid hydrocarbons which are suitable for el purposes, such as oils and tars, are suitable when fixated or When fixated and further treated, to serve as carriers for.

particles. It is desirable to have such a iquid of low viscosity, but not so low as to prevent its being made to carry up to about 45% by weight or particles, depending upon the character of the solid, the carrier and carried forming-a liquid. In the 'case of heavy oils it is for this reason sometimes useful to reduce viscosity. The addition of be given simultaneously,

high percentages ofcoal particles increases the viscosity from that of light oil to about that of a heavy oil. The addition of important amounts of particles to a heavy oil may cause the composite to approximate a paste in its normal consistency. The increase in viscosity due to the addition of carbons to a light oil is greater than to a heavy oil. Therefore, the viscosity of the carrier may well be reduced by blending therewith other liquid of a suitable character. Of the viscosity reducing liquids one may mention pressure still oil, naphthalene and water or oil gas tar. There are other liquids of low viscosity available. It is found. that the lower the viscosity of the components the less heat, and even no heat, need be applied to enable it to readily flow.

Inasmuch as an oil of extremely low viscosity can not be made to carry as high a percentage of particles as an oil of moderate viscosity, it is occasionally desirable to raise the viscosity \of the carrier. This may be done in sevei al ways. The carrier when fixated may be alternately heated and cooled, which ages it and raises its viscosity. Or again there may be blended with the carrier liquid or liquified hydrocarbons of higher viscosity, like pitch and road oils. The best viscosity to load high percentages of carbonaceous particles is about 20 Engler at 20 C. The adjustment of the viscosity, by way ofincrease or reduction thereof, is of considerable importance.

In order to transport particles incorporated in an oil carrler through pipes it is often desirable to heat the mixture so as to increase fluidlty. In the case of a heavy oil it is sometimes necessary to apply a heat of, from 150 F. to 230 F. ,Heating the oil to 150 F. is frequent. In the case of the composite heat is also of value to assist the trans-v portation. The amount of heat varies in each individual case. In some cases it may not be necessary to elevate the temperature 110 over the F., which is considered the nor mal-temperature in the case of oil. Any

elevation of temperature by artificial means over this normal is considered as a heating of the carrier. The heat may be applied either to the liquids when in storage by means of coils or otherwise,*and when in pi es by heating the pipes or-the pumps, here are a number of things that may be done to the components and composite aside from the blending described above.

less. Removal of ash facilitates, therefore, the transportation of the particles and the use of the product carried. All the ash or some of it may be removed from pulverized carbonaceous substance, such as coal or lignite, in any of several known ways, wet

or dry, such as air blast separators, sifting mechanisms, screens and tables, flotation and other mechanical or chemical treatments. Such additional steps assist the preparation of the solid carbons for transportation and may be applied, generally speaking and according to the method, either before, during or after the composite -is made or transported. Upon arrival at destination the particles which are in the suspension class as regards size, may be removed from the carrier by centrifuging, or by filtering, or may be allowed to settle and then the carrier removed. The carbonaceous particles with their coating of oil are highly suited for further treatment to make briquettes or may be used just as they are as a mobile fuel paste. The carrier with the larger coal particles removed, and retaining the coalparticles which are of molecular or colloidal size and which cannot be filtered or centrifuged out, may be used as'a high grade liquid fuel, suitable not only for burnmg purposes, as fuel oil, but also for Diesel engines, semi-Diesel engines, or even internal combustion engines of more delicate mechanism with the aid of the latest carbureters. Or again the composite as piped with its full load of coal may be used as a liquid or mobile fuel, its stability being such that it may be used in oil fuel apparatus. The completed product or the partially separated product may also be used to make gas, instead of the coal and oil being separately treated for gas-making. Or again the fuel may be used for other purposes for which its nature fits it. The removed carrier may be used several times and each time becomes more enriched with colloidal and molecular coal. 'VVhatever. disposition is made upon arrival of the particles and of the carrier, the solid substance in pulverized form has been transported through pipes, which is the vital matter herein treated. Aside from these indications with regard to the possible future utilization of the particles and carrier and of their separation, the subsequent disposal of these substances is not exhaustively dealt with herein.

An example of carbonaceous particles inparticles in the carrier and the dispersion endures for several months to an adequate ex-v tent to enable the composite to be piped without congesting the conduits throu h sedimentation. Thissame method may 0 used to transport coal containing high percentages of ash. The ash, whose specific gravity is high, is also stabilized in the carrier.

Having thus described my invention what I claim is:

1. That method of transporting carbonaceous substance, which consists in reducing the substance to the form of particles, combining the particles with liquid hydrocarbon as a carrier, treated with-substance having stabilizing qualities so as to carry the particles in stable suspense, passing the liquid composite through a pipe-line, and upon arrival at destination removing solid carbonaceous substance with associated liquid hydrocarbon from the carrier.

2. That method of transporting carbonaceous substance, which consists in reducing the substance to the form of particles, combining the particles with liquid hydrocarbon as a carrier, treated with a lime-rosin soap so as to carry the particles in stable suspense, passing the liquid com osite several miles through a pipe-line and tliereupon separating transported particles from most of the liquid hydrocarbon carrier.

3. That method of adaptin carbonaceous substance containing ash so t at it may be transported through pipes, which consists in reducing the same to the form of particles, removing ash, and combining the particles with a liquid carrier comprising high boiling liquid hydrocarbon, which is prepared by the addition thereto of substance having stabilizing qualities, to carry in stable suspense the particles of solid carbonaceous substance reduced in specific gravity by the removal of ash.

4. That method of adaptin carbonaceous substance containing ash so t at it may be more readily transported through pipes which consists in reducing the same to the form of particles, removing ash, and combining the particles with liquid hydrocarbon of moderate viscosity which is treated with lime-rosin soap for stabilizing purposes, the components being blended by mechanical means when heated above normal temperature.

Signed at New York city in the county of New York and State of- New York this 1st day of December A.D 1919.

:LINDON WALLACE BATES.