Patent GB-149306-A (GB)
Title: Improvements in fuel
IPC: C10L1/32
Filed: 1919-12-22
Abstract: A fuel consists of a suspension and a colloidal solution of any carbonaceous particles in any liquid hydrocarbon, whereby the liquid, paste, or gel formed is mobile and may be atomized at the temperature of use, and yet is stable, that is does not settle, for a period permitting storage and transport.  The carbonaceous substance is pulverized or otherwise reduced mechanically, electrically, or chemically, until about and preferably more than 95 per cent passes through a screen of 100 mesh to the linear inch and 85 per cent through a screen of 200 mesh, and is then mixed with the liquid hydrocarbon by passage through a ball, tube, or paint mill, or by heating to 65-95 DEG  C. with or without agitation, or by a combination of these methods, or the solid may be reduced p  in presence of the liquid.  Suitable carbonaceous substances specified are anthracite, semi-anthracite, bituminous and semi-bituminous coals, lignites, peats, anthracite culm, dust, and slush, bituminous and lignite slack, screenings, and dust, coal seam dust, pressure still, smelting, and gas cokes and charcoals, and wood.  Suitable liquids mentioned are fuel oils, pressure-still oil or tar, coal tar from coke ovens or gas works, and molasses, and liquefied solid hydrocarbons.  The liquid should preferably have a viscosity of about 20 DEG  Engler at 20 DEG  C., and 10 DEG  C at 30 DEG  C.  The viscosity may be increased by (1) addition of petroleum or asphaltic pitch, petroleum residues or heavy petroleums; 5-10 per cent of pitch is suitable.  (2) emulsifying the oil as with the lime-resin product mentioned below, followed or not by repeated heating and cooling.  It may be reduced by addition of kerosene, turpentine, pressure-still oil or tar, or other "cut-back."  The stability of the compounds may be increased by (1) increasing the viscosity of the oil as above. (2) addition of "peptisers," which reduce the apparent specific gravity of the particles; coal-tar distillates, particularly croesote, naphthalene, solvent naphtha, and the "green" residual after removal of anthracine are specified; 1-10 per cent is suitable.  (3) addition of a protecting agent or "fixateur" particularly the lime-resin product mentioned.  This product may be in liquid, paste, powder or other solid form, or as grease by addition of oil.  The last and preferred form is made, for example, by saponifying 10 parts resin by 5 parts lime slaked and suspended in 83.5 parts Texas Navy oil and 1 1/2 parts water. The resin may be replaced by balsams, turpentine, and other resinous by-products or by pine-wood pitch, and other alkali than lime may be employed.  Usually such an amount of this protector is used as will add 0.5-1.5 per cent resin to the fuel. (4) promoting the tendency to "get" formation; as by addition of a little extra "fixateur," or preventing vibration or shock, or by keeping the temperature low and constant.  (5) the use of two or more liquid hydrocarbons more or less immiscible, especially when one of the liquids contains solid particles, as free carbon or asphaltum. (6) the addition of "fillers" preferably of lighter specific gravity than the oil.  Cellulosic by-products such as waste from starch, corn, and flour factories, wood pulp, wood dust, particularly that containing resin, and finely divided peat and lignite are mentioned. Liquid products may be obtained containing up to 45 per cent of carbonaceous particles, and atomizable pastes containing up to 75 per cent solid particles. Oils and tars such as pressure-still oil containing free carbon and asphalt may be centrifuged to reduce the percentage of solids. Examples of suitable compositions are: (1) 50.5 parts pressure-still oil, 3 parts pressure-still wax tailings, 1 1/2 parts "fixateur," 30 pressure-still coke, and 15 parts petroleum pitch. (2) 67.8 parts Navy fuel oil, 31.2 parts bituminous coal, 1 per cent "fixateur."  (3) 50 parts pressure-still oil, 1.2 parts "fixateur," 6.8 parts Texas Navy oil, 10 parts coal tar, 2 parts creosote, and 31 parts coke.  (4) 30.5 parts Pacahontas coal ground so that 85 per cent passes a screen of 300 mesch per inch, 69.0 parts texas Navy oil, 1.5 parts of the lime resin grease blended in an ordinary paint-mixing machine with a 200 lb. wheel running at 70 revs. per minute.