Abstract: Disclosed is a process for the flotation of a mineral concentrate comprising the steps of forming an aqueous slurry of a milled mineral ore containing particles of a desired mineral species and adding a flotation reagent which causes a desired variation in the flotation tendency of the desired mineral species present within the slurry so as to increase the efficiency of separation of that mineral species from the slurry relative to a situation where said flotation reagent is absent from the slurry. A stabilising agent is introduced to the slurry in an amount which creates electrochemical conditions conductive to separation of the desired mineral from the slurry and causes the destruction of a deleterious component from the slurry which consumes the flotation reagent thereby maintaining or improving the efficiency of separation of the desired mineral species from the slurry of milled ore.

Abstract: A carbon dioxide snow discharge apparatus having at least two snow discharge tubes wherein at least two of the snow discharge tubes have different internal diameters which can be operated either individually or together to vary the flow rate of the carbon dioxide snow, the snow discharge tubes being joined at selected points along their length.

Abstract: A pressure regulator for lower pressure distribution of gases from a higher pressure source of gas including a gas inlet and a gas outlet defining a gas path therebetween, a regulating element disposed downstream of the gas inlet remote from the gas path, including a resiliently displaceable device responsive to gas pressure and connected to a valve at the gas inlet to thereby regulate the gas pressure at the gas outlet, and to gas distribution systems employing the same.

Abstract: A method and apparatus (1) for the control of biological treatment of waste water in which waste water is fed to a substantially air tight supported growth biological filter unit (2) that includes an exhaust gas vent (5). Dissolved oxygen is supplied to the filter unit and the oxygen consumption rate across the filter is measured by comparing the flow rate of oxygen into the filter (2) to the flow rate of oxygen exiting the filter through the gas vent (5). The feed rate of waste water is adjusted to maintain a predetermined oxygen consumption, thereby controlling the effluent quality.

Abstract: An apparatus (1) for dividing plant materials (4) comprising, a first conveyor (2) to transport a tray (3) or the like so as to selectively position generally upstanding plant material disposed in the tray, harvesting means (7) to grip and sever the plant material (4) adjacent its base when selectively positioned by the first conveyor (2) and to transport the plant material to a dividing station (D), image signal generating and processing means (6) to scan the cutting and cutter means (10) responsive to a division signal from said image signal generating and processing means (6) to divide the plant cutting (5) according to predetermined rules related to the structure of plant material, and planting device (13) to transport and position the divided plant material (17) in a growing medium (20).

Abstract: A freezing tunnel includes a longitudinally extending housing defining a cooling cavity containing a cooling atmosphere which progresses from one end of the tunnel to the other end. An endless mesh belt extends through the housing for carrying articles to be frozen. A shroud is located within the housing and extends transversely across the belt and terminating in edges which define an opening. The shroud defines an inner region and an outer region between the inner region and the housing and includes first and second longitudinally spaced shroud portions, each having respective apertures for allowing fluid communication between the inner and outer regions. Electrically driven fans direct the cooling atmosphere through the respective apertures and the opening and past the articles to be frozen.

Abstract: A gas operated balloon inflating machine for inflating balloons of the kind having a body and a filling neck terminated in a beaded edge. The apparatus includes a gas operated releasable clamping device to secure the beaded edge of the balloon between a support surface and a sealing surface thereby providing for inflation of the balloon from an aperture in the sealing surface. A gas operated control valve selectively supplies gas to the aperture from a reservior and a gas operated sealing device is used to seal the neck of the balloons after inflation. A logic controller selectively supplies pressurized gas from a high pressure source to the clamping device, control valve and sealing means to sequentially clamp, inflate, seal and release balloons. The exhaust gas from each of these devices is directed to the reservoir for inflation of the balloons. The size to which the balloons are inflated is preferably controlled by the size of the inflating reservoir and regulation of the pressure in the reservoir.

Abstract: A coin-freed vending machine for cylinders of compressed gas comprises an outer cabinet having a door-opening, a storage chain conveyor for cylinders within the cabinet and a rotatable transfer cradle between the door-opening and the conveyor preventing access to the conveyor. The transfer cradle is furnished with sensors enabling an empty cylinder placed in it through the door-opening to be identified by a data processor, following which the cradle and conveyor are operated to load the empty cylinder into the conveyor and to unload a full cylinder from the conveyor for extraction through the door-opening.

Abstract: A spray dispenser for a container of a fluid under pressure, having a schrader type discharge valve; consists of a handpiece removably secured on the container and having a spray discharge nozzle in tubular connection with the valve, a movable trigger mounted on the handpiece and connected to the valve so that the trigger is operable to open the valve against the influence of a spring forming part of the valve, and an interlock lever fulcrumed on the handpiece, which is resiliently influenced to obstruct movement of the trigger but is hand-releasable to permit such movement.

Abstract: To vent the contents of a pressure vessel upon failure of the vessel due to overheating or to abnormal pressure increase therein, a safety valve defines two passages through it both leading from the vessel interior to atmosphere. One passage is normally obstructed by a fusible member; the other is normally obstructed by a rupturable disc or like member.

Abstract: Uncured rubber scrap may be segregated from metal and fiber contaminants by the method of first embrittling the scrap by immersion in a liquid cryogen, then impacting the embrittled rubber and magnetically removing metal, and then milling the remainder. Gas flotation is used during milling so that particles of rubber and fiber are selectively removed from the mill and subsequently classified by size, whereby most of the fibrous component is segregated from a remainder. The remainder is then worked so as to increase the surface area of residual fiber prior to further segregation of fiber from rubber by gas flotation. The combined milling and flotation procedure may also be used for separating components of other mixtures. Apparatus for embrittling and milling is described.

Abstract: Apparatus is disclosed for refrigerating a moist article, the apparatus comprising a cold room, means for circulating cooling atmosphere through the cold room, a moisture absorbent liquid cooling spray in the path of said atmosphere, means for collecting and recirculating the liquid in a continuous path, means for admitting a cryogenic cooling fluid to the liquid and means for removing the fluid and absorbed moisture from the liquid before the liquid returns to the spray.

Abstract: A method of freezing animal carcasses comprises spraying the carcass with liquid nitrogen to produce a chilled outer layer thereby to seal the moisture within the carcass for the dual purpose of maintaining the quality of the meat and preventing the frosting or icing up of the heat exchange coils of a forced draught cooling system utilized subsequently to bring the entirety of the carcass to a desired chilled or frozen condition. Also disclosed is a freezing room including means for liberating a cryogenic liquid into the air stream from the fans of a forced draught cooling system for rapid pull-down of the room temperature.

Abstract: Apparatus is disclosed for refrigerating a moist article, the apparatus comprising a cold room, means for circulating cooling atmosphere through the cold room, a moisture absorbent liquid cooling spray in the path of said atmosphere, means for collecting and recirculating the liquid in a continuous path, means for admitting a cryogenic cooling fluid to the liquid and means for removing the fluid and absorbed moisture from the liquid before the liquid returns to the spray.

Abstract: A fusible safety device for a pressure vessel includes a body of fusible material in the form of a tablet which acts as a leak-proofing gasket and is so arranged as not to be vulnerable to creep movement under normal temperature and pressure. The tablet is seated on a floor in a counterbore which puts the inside of the vessel in communication with atmosphere. The tablet is firmly compressed against the floor by a pressure plate in turn loaded by a sleeve screwing within the counterbore. The gas venting passage through the counterbore consists of a vent bore being the lesser diameter portion of the counterbore, and one or more holes in the pressure plate which are essentially out of axial alignment with the vent bore.

Abstract: A manually operable resuscitator includes a manually deflatable gas reservoir to supply gas to a hollow valve housing for controlled supply to and from a patient. The housing has three ports, a first one for connection to the reservoir, a second one for supply to the patient and a third one for exhaust to atmosphere. A distensable diaphragm which is distended by pressure in the reservoir to open the first port and close the third port. A non-return valve controls flow from the first port to the second port. The diaphragm may carry a valve to permit flow from the first to the second port if pressure drops in the latter as the patient inhales.

Abstract: An infant incubator. A substantially rectangular patient support tray forms the floor of an occupant compartment. A substantially rectangular plate is disposed beneath the tray to define therewith a return flow path for taking atmosphere from the compartment from opposite longitudinal edges of the compartment floor. A base is provided beneath the plate to define therewith a delivery path for supplying atmosphere to the compartment at opposite transverse edges of the compartment floor. The base includes a heater to heat the atmosphere flowing over the base under the action of a centrally located impeller indirectly coupled to a motor located beneath the base. Humidifying means can also be provided.