Abstract: A horizontal circular filter is provided which includes plural filter pans arranged in a circle and rotatable as a group around a fixed central vacuum box. The filter pans are connected to respective sections of the vacuum box by respective manifolds which rotate with the filter pans. Each of the filter pans comprises a pan having a flat bottom wall including plural filtrate drainage troughs therein. A removable, disposable, plastic channel-forming grid is positioned on the bottom wall between the side walls of the pan. A filter cloth is disposed over the grid, and a cloth "caulking" arrangement secures the filter cloth in place so as to also hold the grid in place in the pan. A method of retrofitting existing punched plate filter pans is also provided.

Abstract: The invention relates to a device for filtering on a substantially horizontal plane, comprising a filter cloth (50) and a structure (51) for supporting the filter cloth capable of tilting about a horizontal axis (47) and comprising a peripheral groove (48) of uniform cross-section. The cloth is fastened to the support by a hollow tubular gasket (55) made of elastic or substantially elastic material, arranged to interact with the groove; the tubular gasket is designed to distort transversely between a free or contracted state in which it can be easily introduced into the groove into which the filter cloth has been inserted beforehand, and a distorted or dilated state in which it locks the cloth inside the groove by pressure.

Abstract: Apparatus for introducing and mixing a first liquid with a second liquid in which use is made of a spinning disc for throwing droplets of the first liquid centrifugally outwardly, and an agitator immersed at least partially in the body of the second liquid, spaced below the spinning disc, and displacing second liquid upwardly and outwardly from the body of liquid to intersect the droplets of first liquid thrown from the spinning disc for admixture above the body of the second liquid.

Abstract: A process for introducing and mixing a liquid, in a substantially liquid medium, comprising a rotary agitator whose axis is vertical and which is capable of creating a zone of turbulence above the liquid level, the liquid is introduced in the form of a vertical jet which is converted above the level of the liquid medium into a horizontal sheet of droplets to which there is imparted a centrifugal movement, by causing the jet to impinge on a surface that is fixed perpendicularly to the axis of the agitator, and mixing being effected above said level. In its preferred embodiment the apparatus is particularly suited for introducing corrosive liquids into a liquid medium containing solid particles in suspension. It is advantageously used for the wet-process production of phosphoric acid.

Abstract: A process which enables a mixture of liquid and gas, coming from a rotary vacuum filter, to be collected and simultaneously separated.The mixture of gas and liquid is passed from the filter into a vacuum box provided with a space which rotates around the axis of the filter and is generally of circular shape, in which the liquid and gas separate, the liquid is introduced into a lower fixed space generally in the shape of a circular channel, and the gas is introduced into an upper fixed space generally in the form of a circular channel, so that the liquid and gas are collected separately.The process and the apparatus of the invention are advantageously employed in circular table filters divided into filtration zones and provided with wash means, especially in the manufacture of phosphoric acid by the wet method.