Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
  • C10L1/324—Dispersions containing coal, oil and water

Definitions

• the present invention evolves from the inventor's discoveries disclosed in his United States patent 3,941,552 and according to which a fuel in the form of a dispersion is made by mixing finely divided coal, oil, and water and subjecting the mixture to violent sonic agitation sufficient to cause cavitation in the mixture in order to effect a stability of the mixture, i.e., substantial shelf or storage life and the ability to use the fuel without in situ agitation equipment.
• emulsions is intended to include emulsions having particulate matter in dispersion or suspension as a component thereof.
• the term "sonic" includes both audible and ultrasonic frequencies and can be effected by sonic generators such as an ultrasonic probe, or by so-called super mixers which cause violent agitation of liquid sufficient to cause cavitation, or by piston homogenizers operating at high pressures of 1000 to 4000 p.s.i. or higher effecting super mixing by means of liquid being ejected through a restriction to increase its velocity after which it impinges on a plate or ring at which time the pressure and/or impact causes violent agitation and cavitation.
• sonic generators such as an ultrasonic probe
• super mixers which cause violent agitation of liquid sufficient to cause cavitation
• piston homogenizers operating at high pressures of 1000 to 4000 p.s.i. or higher effecting super mixing by means of liquid being ejected through a restriction to increase its velocity after which it impinges on a plate or ring at which time the pressure and/or impact causes violent agitation and cavitation.
• sonifying and “sonification” is intended to include the concept of agitation sufficient to cause cavitation.
• the stabilization effects of cavitation in the process of the invention appear to be applicable to a wide variety of mineral suspensions and dispersions and is very beneficial in fuel dispersions including coke, petroleum coke, peat, and charcoal, as well as coal, among the carbonaceous minerals having noncarbonaceous elements in their make up.
• coal beneficiation without agglomeration as a first step, with agglomeration as a second step, in the processes of the invention is effected.
• the beneficiation step is interrupted and the agglomeration step is modified to accommodate the basic, end result of a clean, stable fuel.
• Sonification is used to enhance both steps and, in the instance of agglomeration, to effect usable agglomerates which lose their identity as such in the final mixing step.
• the in-line production methods of the invention have been found to facilitate improvement of the final product by accommodating the introduction of residual oil as a component of the coal, oil, water product and the use of heated components where desirable, for example.
• One aspect of the present invention provides a method of separating particulate discrete minerals bonded together mechanically by making a slurry of the particles and subjecting the resulting slurry to such intense vibrating action as to produce cavitation within the slurry and the separation of the different components of the particles.
• the present invention provides a method for producing fuel comprising a mixture of coal, oil, and water which method includes the step of mixing particles of coal and impurities with water to form a slurry, exposing that slurry to such violent agitation as to cause cavitation so that the impurities are detached from the coal particles.
• the method also includes the step of separating the detached impurities from the slurry and using those impurities as a by-product, for example, in the production of aggregates.
• the cleaned coal slurry, after adjusting the water content is then mixed with oil and the mixture of coal, oil, and water is treated to form an emulsion.
• the treatment of the coal, oil, and water to produce an emulsion is that described in U.S. patent 3,914,552.
• the agitation of the slurry of coal and water is most desirably affected sonically, and the slurry is exposed to an energy density of at least 3 watts per cm 2 , but in any event sufficient energy density, in combination with a suitable frequency, as to cause cavitation and related to the range of particle size being treated.
• emulsions of coal and water with distillate oil or water with distillate oil which are emulsified and which are stabilized by blending a residual oil with the fuel.
• the present invention contemplates an optional first step of coarse grinding followed by separation of a major amount of the contaminants of the mineral being processed, followed by wet grinding followed by pre-sonification of the suspendant liquid and the particulate material to reduce the size of the particulate material and in case of coal, to further beneficiate the same by releasing from the coal particles, further particles of ash and other impurities not separated out in the first separation step.
• Separation of the impurities from this slurry may then be effected, or while sonification of the slurry is taking place, agglomeration may be induced.
• a minimal amount of the agglomerating liquid is added to the sonified slurry and this mixture is continued to be agitated preferably by sonification sufficient to induce cavitation in the mixture. It has been found that with sonification in the agglomeration step, only small amounts of agglomerating liquid are required.
• the mixture may then be screened to separate out the suspendant liquid. Further bridging liquid may then be added to produce the final product.
• a slurry of coal particulate and water is derived from the initial steps with the coal being approximately 1/3 the weight of the aqueous mixture. That mixture is then sonified to break the ash and pyrites from the coal, and oil as the bridging liquid is added. Sonification of this mixture causes the coal and oil to agglomerate. This mixture is screened to separata out the remaining ash and as much water as desired from the agglomerated mass. Oil is then added to the agglomerated mass, which still retains some water, to the extent desired for the final product.
• the amount of water left in the agglomerated coal can be carefully controlled by the amount and type of oil which is introduced in the spherical agglomeration process just as the coal/water mixture is being irradiated and when the mixture is about to be further irradiated after the introduction of the oil as the agglomerating medium.
• distillate oil in the agglomeration step and residual oil or a blend of residual and distillate oil in the final mixing step.
• the temperature of the water being at least about 35°C.
• Figure 1 is a flow diagram showing a coal benefaction process.
• Figure 2 is a flow diagram showing a coal benefaction process in combination with an agglomeration process.
• Figure 3 is a semi-diagrammatic showing of an ultrasonic reactor.
• coal and water are delivered to an impact mill 10 or to some other appropriate grinding apparatus.
• coal may be delivered to an impact mill 10a and water is added to the coal particles exiting impact mill 10a as, for example, at 12 to form a slurry.
• the slurry exiting mill 10, or that produced by the addition of water to the particles exiting mill 10a, is delivered to a tank 14 within which the slurry is subject to violent agitation in this particular embodiment by irradiating the slurry with sonic energy.
• the sonic vibrations may be generated by known technique, and particularly desirably the vibrations are generated by the utilization of equipment similar to that described in U.S. patent 3,941,552.
• the suitable vibrations Using a typical particle size of 50 to 100 microns or less the suitable vibrations have been found to have a frequency of between 500 and 50., 000 Hz and amplitudes ranging from about 2 x 10 to about 10 microns.
• the energy density should be of an order sufficient to produce effective cavitation within the volume of the slurry. It will be recognized that, dependent upon the density and other characteristics of the slurry, particularly the physical characteristics of the coal particles, the energy requirements will vary.
• the slurry is exposed to that radiation which will produce detachment of impurities bonded to the coal components of the particles and will simultaneously produce diminution of the particle size.
• the water and the coal and impuri ty components of the particles are delivered to a separation unit 16 in which the coal, pyrites and other impurities are separated.
• the denser impurities such as iron pyrites and silica are removed from the unit 16 as at 10 to be discarded or to be utilized in the manufacture of other products.
• the agglomeration process may be induced in the sonic treatment chamber 26, in which case a much smaller amount of oil is added to the slurry, as shall be described.
• agglomeration may be induced in sonic reactor 14 and, in which event, separation may be effected in separation unit 16 or by screening as discussed below with reference to the process shown in Fig. 2.
• a "cleaning" by separation may be performed after the first diminution step and the clean slurry presented to the reactor 14 for the agglomeration step.
• the coal may first be coarsely ground and water is added and initial separation of contaminants with water is carried out by froth flotation, although other separation methods may be used such as sonification of the slurry and magnetic or centrifugal separation.
• the "clean" coal, water slurry is then subjected to a grinding operation to grind the coal to between 100 to 300 mesh.
• the suspendant liquid water in this instance, may be fed from a water supply into a container and mixed with coal in particulate form preferably with a typical particle size of 50 to 100 microns or less, although larger particles sizes 200 microns or more may be used.
• the mixture preferably comprises 60% by weight of water and 40% by weight of coal.
• the mixture may be stirred by a propeller shown in phantom within the container in Fig. 1 and at any rate the slurry is pumped to an ultrasonic reactor of the type disclosed in U.S. Patent No. 3,941,552 and in U.S. Patent Nos. 3,715,104 and 3,749,318.
• the slurry is subjected to sonification, that is, to violent sonic agitation, with an intensity sufficient to cause cavitation and for a time sufficient to reduce the particle size of the coal particulate even further as a result of the pyrites including ash breaking away from the coal.
• sonification that is, to violent sonic agitation, with an intensity sufficient to cause cavitation and for a time sufficient to reduce the particle size of the coal particulate even further as a result of the pyrites including ash breaking away from the coal.
• the slurry may first be subjected to a separation step to eliminate the impurities broken away from the coal particulate.
• the slurry is then pumped to a container where the relatively small amount of the agglomerating medium, in this instance between 1% and 370 by weight of the coal, is added to the slurry.
• the slurry with the agglomerating medium is then agitated or continued to be agitated and, according to the invention, preferably sonified again with
• the agglomeration step is very much enhanced by the use of sonfication, that is, it is quicker and less agglomerating medium has to be used than if agitation of less intensity is applied to the mixture.
• the resultant mixture after sonification of the water/coal slurry and agglomerating oil medium comprises the agglomerated mass of coal and oil and. a mixture of water and ash which is lyophilic to the agglomerating medium but not to -water. The mixture is then screened so that the water and ash are screened out and the agglomerated mass of coal and oil is recovered.
• the screened out water/ash may be brought back upstream through a separating step where the ash and water are separated and the water returned to the water supply to the initial container.
• the agglomerated mass also contains a small amount of water which is quite acceptable to the desirable qualities of the final product sought in this process, i.e., a coal, oil, water fuel with between 10% -
• One fuel of this invention comprises a mixture of about 50% by weight coal particles of about 200 mesh size, 20% water, 25% No. 2 distillate oil, and 5% of No. 4 residual oil and is produced by first forming a slurry of water andcoal. Thereafter, the blended oils are united with the slurry of coal and water and the resultant mixture is subjected to agitation to cause the formation of an emulsion.
• the agitation may be sonic agitation or an homogenizer or other mixing means may be used.
• Another fuel according to this aspect of the invention comprises only oil and water and is produced by blending 5% of No. 6 residual oil with 80% of No. 2 fuel oil and then admixing the resultant blend with water, the water comprising 15% by weight of the mixture. The mixture is then agitated to form an emulsion.
• the emulsion is stabilized by the addition of residual oil and appreciable shelf life is obtained in each instance.
• FIG. 3 is a semi-diagrammatic showing of an ultrasonic reactor 200.
• Ultrasonic vibrations from 20,000-22,000 Hz result from electricity at the same frequency which is shown coming in through wires.
• the vibration is in piezo-electric stack 210 to which is coupled the broad end 220 of a steel velocity transformer which tapers exponentially to a small end 230. It is this end which agitates the dispersion.
• the reactor utilizes a sonic, or preferably ultrasonic, probe in confined space, such as a container 130. It is important that the space between the end face of the probe and the container wall 232 facing it be adjustable and that the channel between the space and wall be of uniform and small dimension so that liquid dispersions flowing between the plates are maintained in a thin or short path exposed to violent ultrasonic vibrations.
• the container is provided with two liquid conduits, one coming in from the side and directed substantially across the space between the end of the probe and the wall, and the other conduit being axial.
• the flow of liquid across the plates makes is possible to have a somewhat extended zone of ultrasonic vibration as the probe end and container wall can be brought close together so that there are not such long paths through liquid as to attenuate seriously the force of the ultrasonic vibrations and in some cases that the amplitude of vibration approximate the spacing between probe end and wall.
• the flow of liquid system across the probe and wall may either be under pressure, that is to say, where the liquid dispersion is pumped in, or it may flow by having the outlet under suction. It is, of course, possible to combine both methods. When pressure flow is used, it is sometimes desirable to increase the pressure downstream from the outlet conduit, which can be done by throttling or other means.
• the pressure on the liquid medium in the zone of agitation, or in apparatus terms in the container, can vary, and in many cases a positive pressure is desirable.

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• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Dispersion Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Liquid Carbonaceous Fuels (AREA)
• Colloid Chemistry (AREA)
• Detergent Compositions (AREA)

Priority Applications (7)

Applications Claiming Priority (4)

Publications (1)

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Family Applications (1)

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Citations (5)

• 1981
  • 1981-03-02 WO PCT/US1981/000259 patent/WO1982003085A1/en active Application Filing
  • 1981-03-02 BR BR8108998A patent/BR8108998A/pt unknown
• 1982
  • 1982-01-19 PH PH26751A patent/PH24575A/en unknown
  • 1982-02-27 ES ES509980A patent/ES509980A0/es active Granted
  • 1982-10-29 DK DK479682A patent/DK479682A/da not_active Application Discontinuation
  • 1982-11-01 FI FI823713A patent/FI823713A0/fi not_active Application Discontinuation
  • 1982-11-01 NO NO823620A patent/NO823620L/no unknown

Patent Citations (5)

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