Abstract: A method for conditioning cooled used moulding sand retaining moulding sand binder in a mixer (1), wherein the cooled used moulding sand is heated to at least a minimum temperature, moisturized by providing water or water vapor through holes in an agitator and subsequently cooled in the mixer from the minimum temperature using the effect of a vacuum.

Abstract: The invention relates to a method of treating power station residues in the form of bulk material, particularly the filter ash from power stations, by hydrating the lime content by adding moisture and by further wetting of the bulk material, with an opportunity for constantly feeding in material to be processed and discharging processed material, and also to an apparatus for carrying out the method. In order to provide a method and an apparatus by which large quantities of power stations residues (ash) can be quickly and safely treated at economic and comparatively low cost, it is according to the invention proposed that the bulk material supplied should pass through a succession of different spatially substantially separate treatment zones be moved mechanically at adjustable intensity throughout the entire process, be differently treated in each treatment zone, be caused to react and transported along a reaction line under control.

Abstract: Described is a pressure-resistant mixer with a feed opening (15), a rotating mixing container (1) with a drainage device (20) and with mixing tools (17) arranged eccentrically to the axis of the mixing container axis (35) inside the mixing container (1), and with drive motors (6, 22) and drive devices (33, 34) for driving the mixing devices (17) and/or the mixing container (1).In order, on the one hand, to avoid sliding seals in contact with the materials being mixed, and, on the other, to avoid having to use extremely large size seals, is proposed in accordance with the invention to position the mixing container (1) inside a stationary pressure vessel (3).

Abstract: In order to reduce the duration of the method of producing lead paste for batteries by mixing lead oxide, sulphuric acid, water and possibly conventional additives below a limit temperature with at least partial cooling, acid is first added at substantially the maximum speed possible for distribution in the mix, without causing burning therein, and so quickly that the amount of heat supplied to the mix is greater than the amount of heat which is removed by cooling, and then, when the material being mixed reaches a predetermined operating temperature which is below the limit temperature, the addition of acid is regulated in dependence on constant temperature measurements in the material being mixed, in such a way that the temperature remains at the level of the operating temperature substantially until the end of the operation of adding acid.

Abstract: A process for the production of agglomerates which are resistant to leaching out, from finely divided waste materials, is characterized in that a hydraulic binding agent is dissolved in water under a condition of forced mixing until it substantially no longer sediments, the resulting aqueous colloidal solution is combined with the finely divided waste materials and in so doing the water content of the mixture is adjusted to an agglomeratable consistency, the mixture is agglomerated through mixing, and then hardened.

Abstract: A method of regenerating old casting sand consists of the steps of introducing essentially dry, used casting sand into a single container, then simultaneously subjecting the sand to rapid heating and extreme turbulence by directing a gas flame against the sand having a temperature of at least 1400.degree. C. (2550.degree. F.) along a first axis, rotating a crushing tool about a second axis parallel to the first axis and positioned such that the crushing tool does not pass through the gas flame and rotating the container about a third axis, parallel to the first and second axes. In a preferred embodiment, the container is cylindrical in shape and the third axis is inclined from the vertical at an angle of between 10.degree. and 60.degree., thereby creating upper and lower zones. The burner flame preferably is directed to the sand in the lower zone and the crushing tool is positioned to operate in the upper zone.

Abstract: An apparatus for electrically heating conductive bulk materials by resistance Joule effect heating includes end and side walls defining an oven chamber having an inlet and an outlet. A plurality of pairs of generally planar electrode plates are angularly mounted with respect to the opposed end walls of the chamber and are electrically disconnected from one another. The electrode plates mounted to each end wall are disposed at the same angle and are arranged such that the upper edge of each electrode plate is at a different distance from the end wall than the lower edge of the plate, so that the planes of the plurality of electrode plates mounted to each end wall are substantially parallel and vertically displaced from each other. The electrical supply for each pair of electrodes plates is electrically isolated from that of each other pair. The amount of energy supplied to each pair of electrode plates is adjustable.

Abstract: A method of preparing foundry sand by measuring moisture and compressibility includes the steps of determining a set of desired characteristics for compressibility and for moisture in accordance with a particular clay content, measuring the actual compressibility in a first stage early in the processing of the foundry sand, adding moisture in accordance with the difference between the moisture for the measured compressibility and the moisture for the desired compressibility to bring the foundry sand to a predetermined value in accordance with the assumed set of characteristics, making a second measurement of the compressibility in a second stage as a countercheck near the conclusion of the processing, measuring the difference between the actual compressibility at the second stage and the desired compressibility, and employing such difference as a correcting value to adjust the calibration of the first measuring stage.

Abstract: A closure member (11) for opening and closing an outlet orifice (30) in a stationary cover (32) of a drum (1) drivable in rotation in a processing machine, in which the material being treated is conveyed upwards towards the outlet aperture, which is provided generally at the lower region of the drum. Closure member (11) is movably fitted to the cover (32) and is at least partly closable.

Abstract: Described is an apparatus for closing and continuously emptying the container of a processing machine by means of a closure cover (6-9) which is arranged in the bottom (1) of the container and which is driven so that it can be moved into and out of the emptying opening (2) in the bottom (1) of the container by way of a pivotal shaft (17) acting as a lifting means on a mounting means, for example a mounting arm (16), outside the container.

Abstract: A method and apparatus for measuring water content of flowable mixtures such as casting sand, concrete, or chemical mixtures. The mixture is agitated in a mixing tray (10), then a moisture sensing measuring probe (7) is inserted into the mix for taking a measurement. The probe is then withdrawn from the mix and cleaned, as by brushing, stripping, blasting with air, or spraying with liquid. A temperature sensor (8 ) may also be inserted into the mix with the measuring probe. The probe is mounted in a lifting unit (5) which normally holds the probe in a cooling and cleaning casing (6) out of the mix. The unit can also locate the probe at different selected levels within the mix.

Abstract: In the disclosed method, granules or pellets are formed from meltable glass-producing mixtures which comprise sand and a sodium-containing component. The sodium-containing component consists at least partially of aqueous sodium hydroxide. The remainder of the sodium component may comprise sodium carbonate or other sodium salts or compounds. The glass-producing mixture may also contain other solid components customarily found in such mixtures. In accordance with the inventive method, the sand grains are treated with the aqueous sodium hydroxide at elevated temperature and without direct contact with CO.sub.2, whereby a surface layer of water soluble silicates is formed on the sand grains. The sand is then mechanically treated in order at least partially to dislodge or remove the water soluble silicates from the sand grains.