Abstract: A process for hydrogenating coal in the liquid phase in the presence of a catalyst comprising an iron oxide obtained by decomposition of an iron compound in a flame, in particular in the flame of a torch. A co-catalyst, such as SnO.sub.2, also prepared by decomposition of a metal compound in a flame, may be added to the iron oxide.

Abstract: The invention is related to a tank designed to contain a cryogenic liquefied gas and formed in addition to the main tank by two other tight walls.In the upper part of this tank an aperture duct connects the ceiling of the tank to the exterior of the tank, a holder supporting a device sensing in various areas wall temperatures of the tank, can be fitted into this aperture duct, a remote temperature sensor is actually hold by this support and is introduced into the tank.The invention finds an application as a means to easily localize leaking failures of the intermediate wall.

Abstract: A gas burner associated with a combustion chamber constitutes a fluid-tight removable heating unit immersible in a liquid to be heated. The unit has a caisson including a chamber for premixing and distributing gaseous fuel and a combustion chamber separated from the premixing chamber by a flame stabilizing grate. The caisson has traversed, in fluid-tight relationship thereto, by ducts permitting thermosiphon circulation of the surrounding liquid and increasing the exchange surfaces constituted by the walls of the caisson.

Abstract: The invention is related to a tank for liquefied gas composed by a triple wall limiting three successive spaces from which two are insulation spaces.The external insulation space contains a substance able to sublime and condense from gaseous state to solid state when cooled by a flow of liquefied gas caused by accidental failure into space.An application is the construction of the tanks of methane carrier.

Abstract: The metallic gas-burner of the invention comprises a central fire-tube constituting a mixing and combustion chamber into which is admitted a fuel-gas and a gaseous combustion agent from an annular air-box surrounding the fire-tube.The fuel-gas is supplied at a low pressure into the rear of the fire-tube and the gaseous combustion agent is distributed at a low pressure into the fire-tube, in the form of at least three main flows from the rear to the front of the tube, the second and third flows being provided in counter-rotation relationship.

Abstract: This invention relates to arrangements for the prevention or minimization of over-pressures due to sudden interruptions in the flow of a compressible fluid which are caused by an obturator such as an electrical valve along a main gas pipe and more particularly relates to such arrangements which consist of a pressure regulator and reducer mounted on the said main pipe upstream of the obturator and the response time of which is longer than that of the said obturator, a venturi which communicates with that section of the main pipe which is situated between the obturator and the regulator and reducer, and a buffer reservoir which is in permanent communication with the said section of main pipe via the venturi. According to the invention the regulator and reducer also forms a venturi.

Abstract: A system for remote reading of indicating devices such as meters and the like, which devices are comprised of a plurality of switch contacts and associated resistance elements. The reading systems senses the closing of one or more of a group of device contacts and does so using only a single pair of sensing lines for each group. Additionally, means is provided for sequencially selecting pairs of lines from a plurality of said pairs of lines, each pair associated with a single group among several assemblies of many groups. The selected pair of sensing lines is routed to an analog-to-digital converter, the output of which is sent to a computing device for processing the data received on the pair of sensing lines.

Abstract: A device for and method of using the heat provided by a heat source and consisting in using as a heat-conveying fluid a substance chemically compatible with porous materials through which the fluid is flowing and which are not substantially wetted by said fluid and subjecting said fluid at the fluid supply to a pressure higher than that of the gas evolved which has passed through a blocking layer included in said porous material and forming a barrier for said fluid in any condition other than the gaseous state.

Abstract: This invention relates to supply circuits for fluids under pressure, particularly gases. Such circuits ordinarily comprise a main pipe between a source of fluid and a point of consumption, and to which main pipe is fitted a regulator and pressure-reducer and at least one obturator is normally fitted to this main pipe downstream of the regulator and pressure-reducer. In such an arrangement, the present invention provides means for minimising over-pressures consequent on the said obturator closing which are caused by the inertia of the regulator, which means is fitted as a by-pass to the main pipe on either side of the regulator and pressure-reducer. In one preferred embodiment, this means comprises a venturi and a reservoir which is connected by a first pipe means to the venturi and wherein the venturi is fitted to a second pipe means as a by-pass to the regulator and pressure-reducer, a valve being provided in the second pipe means upstream of the venturi.