Patent GB-1255617-A (GB)
Title: A toilet waste storage system
IPC: E03D5/016
Filed: 1968-12-19
Abstract: 1,255,617. Sanitary closets; toilet waste disposal systems. GENERAL AMERICAN TRANSPORTATION CORP. 19 Dec., 1968 [20 Dec., 1967; 23 Sept., 1968], No. 60527/68. Heading E1C. A sanitary closet and waste disposal system for use on vehicles such as aircraft, buses, boats and trains, or on sites lacking conventional sewage treatment facilities, comprises a toilet pan discharging into a first tank which includes liquid level sensing means adapted, upon the level of liquid in the tank reaching a predetermined level, to open a valve causing discharge of the contents into a second tank on which is mounted heating means adapted to volatilise out of an opening at least part of the waste liquid transferred from the first tank to the second tank. In the embodiment of Fig. 1, a single container is divided by a horizontal wall 14 to form separate first and second tanks 13, 17, the former receiving the waste from a pan 11 and having a communicating aperture 18 in the wall 14 to the tank 17, this aperture being normally closed by a valve 23. The valve is operable by energising the coil 22 of a solenoid, this being accomplished automatically when the level of liquid in the tank reaches a detector 55 via control apparatus 58 which includes means for reclosing the valve when the level falls below a second detector 60. The valve 23 may also be operated manually in conjunction with a valve 38 for discharging waste from the second tank to an outlet 49 in, e.g., the fuselage of an aircraft, this being effected by an attendant pulling a handle 29 which is connected by respective cables 20, 45 to the two valves 23, 38. Heating pipe 100 is mounted on tank 17 below its bottom wall and is furnished with hot air, e.g. air produced, by the aircraft engines, so that while the aircraft is in flight the liquid portion of the waste in tank 17 is continuously volatilised. The vapour produced is passed via a pipe 105, relief valve 106 and pipe 107 to a biological and odour filter 108, and thence via pipe 109 to the atmosphere. Some of the vapour may be condensed to produce flushing water for the pan. In the embodiment shown, however, flushing is effected by recirculation of liquid in the tank 13 via a pump 31 and filter 32, the pumped liquid passing via a pipe 110 to a flushing ring 111. Chemical liquid is added to the tank 13 at suitable intervals via inlet 65, pipes 66, 68 and check valve 67, prior to which both tanks may be flushed by supplying liquid through pipes 86, 81 and 82 to spray rings 80 and 83. The apparatus may be combined with the waste pipe 93 from a sink via a three-way valve 92 and pipes 91, 95, the valve 92 normally being set to deliver into tank 13, i.e. when tank 17 is being heated, but being set to deliver into tank 17 at other times. In a modification (Fig. 2, not shown) the filter (32) and pump (31) are combined with the valve structure, which is operated by a compressed-air cylinder (153) instead of by a solenoid. In the embodiment of Fig. 3, two first tanks 13', each of which receives the discharge from a pan 11, discharge into a common second tank 17' via conduits 160, 161, 162 under control of separate solenoidoperated valves 23 both of which, together with the valve 38 in the second tank, are manually operable by the handle 29, through cables 20 and 45. This embodiment also includes a heat exchanger 180 for cooling and condensing the vapour passing through the pipe 107 and filter 108, there being provided an inlet 191 for the vapour, outlets 181, 192 for condensed water and vapour, respectively, and an inlet 188 and outlet 189 for cooling air. In the embodiment of Fig. 5, a flexible conduit 230 is fitted between first tank 13' and second tank 17', the valve closing communication between the tanks being in the form of gripping rods 283, 286 carried on the ends of levers 282, 285 which are rotated in opposite senses by a reversible motor 277 and gearing (Fig. 11, not shown) to cause the rods 283, 286 to squeeze the flexible conduit to a closed condition or open it as desired. In addition, a thermal shield 256, which is slidable to and from a position blocking the entrance to the second tank by an hydraulic cylinder 257, is provided to prevent hot vapour reaching the conduit 230 when the heating arrangement, which in this embodiment comprises both a volatilising heater 252 and an incinerating heater 253, is in operation. The heaters 252 and 253 are electric. Tank 13' includes a solids separator 238. In a modification (Fig. 15, not shown) solids are separated by a screen dividing two sections of the tank (13') one of which has a sloping bottom guiding the solids to the flexible conduit (230).