Patent GB-723336-A (GB)
Title: Apparatus for converting a mixture of super-heated steam and a finely divided volatilisable fuel oil, or coal dust, into a combustible gas
IPC: F02M21/00
Filed: 1952-02-12
Abstract: 723,336. Gasifying finely divided fuels. SMITH, J. H., and GRIERSON, R. Feb. 5, 1953, [Feb. 12, 1952.] No. 3644/52. Classes 55 (1) and 55 (2). In apparatus for producing a combustible gas from a finely divided volatilizable fuel oil or coal dust there is provided two working cylinders 11 and 12 having inlet and outlet valves 13, 14, 15 and 16 and a common piston in the form of a column of liquid 28 in an upright U-shaped container, opposite ends of the column of liquid co-acting with the two cylinders, and means for igniting a charge of a combustible gas and a gas containing free oxygen in the cylinder 11 so as to displace the column of liquid to compress a charge of a mixture of finely divided fuel and steam in the cylinder 12 so that the temperature of the mixture is raised to a level at which the fuel reacts with the steam, a reverse displacement of the liquid column serving to compress in the cylinder 11 a further charge of combustible gas and gas containing free oxygen for repeating the cycle. As shown, the cylinder 11 has a sparking device 27 for igniting a mixture of a combustible gas and air in the cylinder 7, the upper parts 22 of the U-shaped container form annular boilers producing steam for the process, the steam being superheated in superheater 24. Finely divided fuel is introduced into the superheated steam through an inlet 25 and the mixture enters the cylinder 12 through a pipe 26. The valves 13, 14, 15 and 16 are arranged to be actuated in succession by the rotation of a shaft 21, and cam devices 20 acting on links 19 and connected by rockers 18 to the valves. The shaft 21 is rotated by movement of floats 44 and 45 connected by a flexible link 43 which moves a grooved wheel 40 as the floats rise and fall with the column of liquid. The arrangement is such that a wheel 30 on the shaft 21 is rotated through 90 degrees for each movement of the liquid column. In the position shown all four valves are shut and a compressed charge of combustible gas and air is about to be ignited in the cylinder 11. As a result of this ignition the column of liquid is moved to compress in the cylinder 12 a charge of fuel and steam previously admitted through valve 15. At the end of this compression the outlet valve 14 of the cylinder 11 opens and the reverse displacement of the liquid column exhausts the cylinder 11. During the following movement of the liquid column the valve 14 is closed and the valve 13 opens to admit a fresh charge of combustible gas and air to the cylinder 11, while the valve 16 of the cylinder 12 is also open to allow the combustible gases therein to pass forward to a gas holder (not shown). At or near the end of this part of the cycle valves 13 and 16 close and the valve 15 opens to admit during the next movement of the liquid column a fresh amount of fuel and steam, the charge in the cylinder 11 being compressed before it is ignited by the device 27. The apparatus may be modified to work on a two-stroke cycle, pressure responsive members inside the cylinders being arranged to operate the inlet and outlet valves thereof. Heat insulated floats may be provided on each surface of the liquid column and those portions of the cylinders 11 and 12 not surrounded by the boilers 22 may be heat insulated. The effective stroke of the column of liquid may be of the order of about 30 feet.