FR2738257A1 - Accelerated fermentation of domestic and green waste - Google Patents

Abstract

Fermentation of waste material uses a large-dia. tube (1) with inner welded partitions (3) and inclined vanes which link them, forming cells of small capacity. As the tube rotates, the waste material drops from the cells successively over a height of > 2 m onto deflectors so that any lumps are broken up. Air and water feeds (6, 7) create a favourable medium for the development of bacteria, promoting a rise in temp. to > 80 deg C, in which pathogenic germs are destroyed. The water feeds are contained in an upper beam and are controlled automatically by electrically-operated valves connected to a moisture sensor inside the tube. The temp. of the air feed is governed by a temp. sensor and the tube is rotated by variable-speed pneumatic friction tyres (filled with nitrogen or water, depending on the geographical situation) and a redn. gear system which turns it at 4-12 revolutions/hr.

Description

The present invention relates to an accelerated fermentation installation in a closed enclosure, constituting the digester,
This large diameter tube 5 to 6 meters, separated by partitions joined by pallets thus forming small capacity cells, trapping air at each tilting of the shredded material, mechanical mixing, energetic successive falls of more than 2 m, on the deflectors and turning over by the rotation of the pallets, ensure the breaking up of agglomerates of heterogeneous products, the bacteria grow in: greater number, water spraying, air injection, creating an environment favorable to good development of bacteria, accelerating the thermophilic phase, these leading to good fermentation
In known installations of this type, the tube does not have any partitioning, or cell, no advancing device with a fall.

The invention overcomes these drawbacks and aims to produce an accelerated fermentation tube, allowing mechanical stirring with control of thermogenesis.

For an installation of the aforementioned type, this object is achieved in accordance with the invention, because the tube is of large partitioned diameter, is separated into cells, an adjustable deflector ensures the advancement: of the products.

The fermentation installation shown in the drawings comprises a large diameter tube 5 to 6 meters, made of welded steel sheets of very thick, waterproof.

Steel bearing rims (2) fixed on the outside of the tube at both ends, ensure contact with the tires for rotation.

The partitions (3) the number is a function of the capacity of the tube (tonnage to produce) these partitions separate the mass of product avoiding compaction. The sectors (4), 12 in number, make up the alveoli, ensuring a lifting and transport role for the fall of
CettE products: fall due to an attrition effect between the products and advancement in the following cells, the fixed beam assembly (5) is formed by an upper water supply tube (6), equipped with solenoid valves and sprayer ensuring the humidity of 50 z inside the tube, two lower tubes (7) for injecting hot and cold air, openings judiciously distributed along the length, diffuses the air inside of the tube.

The inclined deflectors! 8) in two parts articulated in the middle, two cables connecting the movable part of the deflectors from the inside, increasing or decreasing the speed of advancement or product inside the tube, thus regulating the degree of fermentation , and temperatures from 5G to over 800 degrees celius.

A chute (12) ensures the introduction of the shredded material into the tube
The tube rests on two chassis (9) positioned at the two ends, by means of 4 pairs of tires (10) paired, inflated with nitrogen, or with water, depending on the geographical location of the installation, a variable speed reducer (11), causes the tires to rotate, by friction on the running gear and ensures slow rotation of the tube from 4 to 12 revolutions per hour.

Claims (7)

1. Installation of accelerated fermentation in a closed, rotary enclosure, of fermentable ground material of household waste, or of green waste, finely ground. comprising a large diameter tube (1) into which are welded partitions (3) for separating the product from inclined pallets (4) connect the partitions to each other, constituting cells of low capacity, which by rotation of the tube causes successive falls more than 2 meters on the deflectors, thus breaking the product agglomerates, the falls being guided by the deflectors in the following cells, a beam formed by the special water and air supply tubes (6 and 7), creating an environment favorable to the development of bacteria, this causes the temperature to rise by more than 80 degrees celius, destroying pathogenic germs. 2. Partitioning device according to claim 1 characterized in that the partitions (3) constitute the holding element of the cell as a pallet support 3. A turning and advancing device according to claim 1, characterized in that the rotation of the tube angularly positions the vanes (4) in flow on the deflectors (8) having the effect of trapping air, during overturning and to break up the agglomerates. 4. Device for spraying water, according to claim 1, characterized in that the upper beam element contains the water tubes, equipped with solenoid valve and controls automatically, according to the hydrometric value inside the tube. 5. Air blowing device according to claim 1 - 4, in that the lower profiles of the beam encloses the air blowing tube (6 and 7), hot and cold, with judiciously distributed openings, insufflation air, equipped with solenoid valves with automatic control, depending on the temperature inside the tube. 6. Rotation installation according to claim 1, in that the tube is driven by means of friction tires, at variable speed. 7. Installation according to any claim from 1 to 6,  in that the means of mechanical mixing and falling  and turning, under optimum conditions of humidity and temperature promotes fermentation.