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
  • C10L1/326—Coal-water suspensions
• • 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
• • 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 relates to a liquid fuel comprising pulverized coal dispersed in a liquid, which has a very long storage life and is suitable for transport and energy production. More particularly, the invention relates to a dispersion comprising a liquid which at least partially consists of water, pulverized coal and additives, the coal content being at least 60 % by weight.
• a dispersion of coal is considerably less pollut ⁇ ing and can be more easily handled than solid coal and also eliminates some risks involved in transport and storage. Such a dispersion is also preferred from an economical point of view.
• Physical conversion is another method of transform ⁇ ing the coal into liquid form, and the invention relates to this method. It is practised by dispersion in a
• OMPI liquid which may consist of water only or water in combination with some organic fuel such as heating oi 1 , ethanol , etc.
• the present invention principally relates to a dispersion of pulverized coal in water.
• One of the problems in producing a coal-water fuel is that the surface structure of the coal is modified in removing impurities, often by means of chemical additives, and that the dispersion of the coal particles in a later processing stage will be more difficult as a consequence thereof.
• the process of manufacturing a coal-water fuel often includes removal of inorganic constituents in one way or the other.
• the. coal is ground in one or more mills to a polydisperse particle size distribution. All particles are smaller than about 300 microns and about 35 % of the total amount are smaller than 40 microns.
• a main process step included • therein is a flotation enrichment of the coal, which by selective hydrophobization and charging separates coal and contaminants.
• different types of reagents are used which generally comprise mixtures of aliphatic alcohols together with a frothing agent.
• Other reagents which are suitable in the flota ⁇ tion of coal are mixtures of zwitterionic surfactants and oils insoluble in water together with a frothing agent and trace amounts of al kylsul pho-succinates .
• surfactants of the first main type anionic surfactants have shown to be the most suitable.
• surfactants which can be used are alkylaryl-sulpho- nates and al kylsul pho-succi nates .
• dispersion agent In the final processing stage in manufacturing the coal-water fuel a dispersion agent and possibly a stabilizer are added.
• dispersion agents already known for pulverized coal in water or oil are e.g. anionic polynaphtalen sulphonates, polycarboxyl ic
• the total amount of dispersion agent calculated as a weight percentage of the total dispersion is completely decisive for the physical properties of the dispersion.
• the dispersion agent is one of the significant items of expenditure in the manufacture of the dispersion.
• the present invention provides a method of effecting dispersion of coal particles with the same type of basic compound but with different charges.
• Particularly active dispersion agents are built-up around a hydrophobic aromatic part and one or more hydrophilic ethylene oxide chains.
• the molecular charge can be anionic, cationic or preferably zwitterionic.
• the charge of the molecule is varied with the surface charge of the coal itself.
• zwitterionic compounds of ttiis type it is suitable to choose a zwitterionic alkylaryl ethoxylate e.g. sodium nonyl phenetoxy methyl tauride.
• the compound is most easily produced by a reaction between the terminal hydroxide group of the nonyl phenol ethoxylate and sulphonyl chloride, the resultant halid-e being allowed to react vfith sodium methyl tauride
• the sum formula of the compound is
• zwitterionic compounds which constitute excellent dispersion media for certain coals are ethoxylated quartenary nitrogen sulphates . This type of compound is sold commercially by GAF under the designa ⁇ tion PC-37.
• Cationic compounds which can be used according to the invention are based primarily on pyridine and quinoline. An aromatic ring structure with hydrophobic properties is common to them all. Pyridine reacts with ethers to form compounds of the type alkoxymethyl pyridine.
• These cationic dispersion agents are characterized in that they contain at least 50 ethylene oxide units.
• anionic dispersion agents which are applied to a less extent due to the higher price thereof there may be mentioned salts of alkylaryl ethoxylate.
• Anionic compounds of this type are most appropriate for hydrophilic coals.
• All dispersion agents according to the invention have mole weights over 1,500 and are soluble in water.
• the invention will be described by means of an illustrative example.
• a non-mi celle-forming and therefore relatively sparingly soluble zwitterionic surfactant such as lecithin or alkyl betaine is emulsified in water to form a liquid crystalline phase.
• the emulsion (0.03 % by weight of the coal) is supplied to the grinding step of the fuel preparation process.
• a preparation consisting of lecithin, hexadecane and methyl- isobutyl ketone is added in the ratio 1/5/2.
• the total additive amount and the composition can be varied for different coal qualities (0.01 - 0.05 % by weight of the coal).
• alkylsulpho-succinate 10 - 50 g/ton coal
• the filter cake contains between 15 and 22 % moisture.
• About 90 grammes of the moist purified coal filter cake from the process (22.2 %) is homogenized and mixed with 0.25 grammes dispersion agent dissolved in water and comprising an ammonium salt of nonyl phenoxy polyethylene oxyethanol with a mole weight of about 5,000.
• the dispersion obtained in this manner has excellent properties for transport and direct combustion as a liquid - fuel.
• a gelation agent can be added to the dispersion.
• the gelation can be reversible as well as irreversible. Reversible gelation can be attained with small amounts of polysaccharide, xantan gum, guar-gum, alginate or a modified starch in combination with a metal ion, e.g. aluminium or boron.
• the reversible gelation process can be controlled by changing the temperature or the pH.
• Irreversible gelation of the coal-water dispersion can be effected e.g. by means of different clays, bentonite, Chinese clay, etc.
• the fuel product obtained has now a clearly pseudoplastic rheology.
• the coal-water fuel has been found to be a very good oil" substitute for heat as well as steam production.
• the fuel is purified from a lot of inorganic contaminents and is preferred from an environmental and handling point of view to conventional coal technology.

Landscapes

• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Dispersion Chemistry (AREA)
• Emulsifying, Dispersing, Foam-Producing Or Wetting Agents (AREA)
• Liquid Carbonaceous Fuels (AREA)
• Solid Fuels And Fuel-Associated Substances (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
• Processes Of Treating Macromolecular Substances (AREA)

Priority Applications (5)

Applications Claiming Priority (3)

Publications (1)

Family

ID=20351581

Family Applications (1)

Country Status (7)

Citations (5)

Family Cites Families (1)

• 1982
  • 1982-11-12 AT AT82903239T patent/ATE32747T1/de not_active IP Right Cessation
  • 1982-11-12 DE DE8282903239T patent/DE3278166D1/de not_active Expired
• 1983
  • 1983-11-14 BR BR8307709A patent/BR8307709A/pt unknown
  • 1983-11-14 AU AU22621/83A patent/AU2262183A/en not_active Abandoned
  • 1983-11-14 AT AT83903622T patent/ATE32607T1/de not_active IP Right Cessation
  • 1983-11-14 DE DE8383903622T patent/DE3375730D1/de not_active Expired
  • 1983-11-14 EP EP83903622A patent/EP0143782B1/en not_active Expired
  • 1983-11-14 WO PCT/SE1983/000396 patent/WO1984001957A1/en active IP Right Grant
• 1984
  • 1984-12-11 FI FI844890A patent/FI75862C/fi not_active IP Right Cessation

Patent Citations (5)

Non-Patent Citations (2)

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