GB490426A - Method for the treatment by fermentation of waste refuse and of vegetation and apparatus for the application of said process - Google Patents

Abstract

490,426. Manures. SOC. EAU ET ASSAINISSEMENT ANCIENS ETABLISSEMENTS C. GIBAULT, and CHIDAINE, P. E.G. Feb. 12, 1937, No. 4262. [Class 111] A process of fermenting waste refuse, or grass, plants, straw, &c., by subjecting the refuse, &c., in a cell to the simultaneous action of air and water is characterized by continuously sprinkling the refuse, &c., with water while air is caused to circulate by suction applied below a perforated base supporting the refuse, &c. The water should have a pH value between 7À5 and 8, and water from sewers is suitable. The temperature should be maintained at about 65 to 70‹ C., and the operation may be started bv the addition of a small quantity of warm water. Fertilizing substances such as iron, zinc or ammonium sulphates, manganese or iron oxides, calcium, iron or magnesium carbonates, ammonia, phosphates, silicates, crushed rock, or animal refuse may be added to the refuse. A fermentation cell (Fig. 1) is formed with removable gratings 1 of small mesh, or of large mesh covered with rags 2, and with ports 3 for removal of the mould. Each cell is provided with a control board 4, Fig. 3, carrying a flow meter 9 and valve 8 for controlling the supply of water from conduit 7 to sprinklers 11. An evacuating conduit 12 draws air through tubes 17, 19, the cell, tube 20, flow meter 14 and regulating valve 13. A reversing valve 15 enables the air to be circulated upwardly through the cell. Condensed water flows to conduit 22 through siphon 21. The control hoard is also provided with a thermometer 24, manometer 25 and port 26 for withdrawing samples. The liquid traversing the refuse is discharged through siphon 23 into conduit 22. Several assemblies of plant are described and illustrated. In Fig. 6, the cells A are arranged on either side of a gallery formed with a gulley containing tipping buckets E for receiving the mould discharged through ports C. The untreated refuse is lifted from pit O by grab Q, passed through sieve S and conveyed to trapdoors T covering the cells. The liquid passing through the cell is collected in cesspit F, and is pumped therefrom to reservoir Y supplying the sprinklers. Prior to discharging the material into buckets E, it is dried by stopping the water supply whilst maintaining the air circulation. The fermented material is sieved, giving a finished product, inert material and combustible material, the latter being burnt. The ashes, containing potassium, are tipped into the cesspit. In a modified plant, the cells'are in the ground, the refuse being directly tipped thereinto. The reservoir is disposed around the upper part of the furnace chimney. In a further modification, the refuse is directly tipped into the cells in the ground, and is ultimately discharged by grabs into buckets or a belt conveyer moving over a raised platform. Fig. 18 shows a cell for the continuous treatment of refuse, wherein the lower part is subdivided by fluid-tight partitions 69 on the top of which rests a grating covered with waste rags. Each compartment 72 is connected to a conduit through a siphon 74, and also to a suction pipe for air having means whereby the degree of suction in any of the compartments may be varied dependent on the state of fermentation and the nature and thickness of the refuse. Two water sprinklers are provided, each near and parallel with a side wall of the cell. The refuse is continuously tipped into, and when converted, removed from the cell, the space left on removal of the mould being filled with fresh refuse. In another construction, the air drawn through the cells is passed' under the grating and/or into the bottom of the chimney of a furnace.