WO1999064373A1

WO1999064373A1 - Composting arrangement for night-soil and other degradable material

Info

Publication number: WO1999064373A1
Application number: PCT/SE1999/001038
Authority: WO
Inventors: Bertil Östbo
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-06-12
Filing date: 1999-06-11
Publication date: 1999-12-16
Anticipated expiration: 2000-12-12
Also published as: SE513767C2; SE9802102L; AU4812599A; SE9802102D0

Abstract

The invention relates to a composting arrangement for night-soil and other degradable material. The arrangement comprises a container (1, 2) with a first inclined plane (3), arranged in the lower part (1) of the container, for receiving material which is to be broken down from a toilet bowl or the like, which is connected to an opening (5) arranged in the top surface of the container. In the container, a second inclined plane (10) is arranged above the first plane (3) and in such a way that it slopes in the opposite direction to the first one. The top surface of the container is designed with a second opening (11) for connection to a second toilet bowl or the like, from which material which is to be broken down is supplied to the second inclined plane. The two inclined planes are each provided with an active starting bed for accelerating the breakdown of the material supplied to each inclined plane. The lower edge of the second inclined plane is located above the first inclined plane, so that material which has been broken down or is in the process of being broken down on the second inclined plane can drop onto the material on the first inclined plane and participate in the continued breakdown of this material.

Description

COMPOSTING ARRANGEMENT FOR NIGHT-SOIL AND OTHER DEGRADABLE MATERIAL

The present invention relates to a composting arrangement for night-soil and other degradable material, comprising a container with a first inclined plane, arranged in the lower part of the container, for receiving material which is to be broken down from a toilet bowl or the like, which is connected to an opening arranged in the top surface of the container, and a second inclined plane which is located above the first plane.

Composting arrangements of this general type have long been well known and, from the environmental point of view, represent a much better alternative, for management of biodegradable material, than the water-flushing systems which are commonly used today and which cause serious and increasing damage to the environment.

When such a composting arrangement is being set up, a starting bed of compost earth containing the necessary bacteria and maggots is arranged on the inclined plane. The degradable material which is supplied to the plane at its highest end is thus broken down as it gradually moves towards the lowermost end of the plane, where the compost earth formed can be removed. In addition to night-soil, the arrangement can be supplied with, for example, degradable household waste. No detailed description of the breakdown process employed will be given here, as this is well documented in, among other places, the patent literature.

For the compost container to have the required capacity to cope with peak loads, it will need to have a large volume and considerable height, especially where the material is supplied at the highest end of the inclined plane. The volume of the composting material decreases as it is being broken down and as it moves towards the lowermost end of the plane. This means that there is an unused volume in the container at the lower end of the inclined plane if the container is designed with substantially constant height. Even if the height of the container is reduced towards the lowermost end of the plane, it is often difficult to achieve any practical use of the space which is thus freed. Such a shape also complicates the manufacture of the container, making it more expensive.

SE 376229 describes a composting technique which involves urine separation, and where faeces is composted separately and urine composted separately, entirely independently of each other and without being mixed.

The known arrangement comprises a single toilet bowl provided with an arrangement for urine separation. The faeces is dropped onto a compost heap and the urine is diverted to a matting or the like of inactive material. The matting of inactive material is arranged on an inclined plane and the final product in the form of broken down urine is led to a pipe.

This arrangement does not provide for any increase in capacity in respect of breakdown of faeces since all the faeces is collected in a single heap. In the event of peak loading, there is therefore a risk of overloading of the installation.

The main object of the present invention is to make available a composting arrangement with a container which is simple and inexpensive to manufacture and whose full capacity can be utilized to a large extent, so that it provides a considerably greater capacity than previously known containers of the same size.

According to the invention, this is achieved by the fact that the space above the relatively low compost bed, near the lowermost end of the inclined plane in the container, is also used for composting purposes.

The special characteristic feature of a composting arrangement of the type mentioned in the first paragraph is that the second inclined plane slopes in the opposite direction to the first one, that the top surface of the container is designed with a second opening for connection to a second toilet bowl or the like, from which material which is to be broken down is supplied to the second inclined plane, that the two inclined planes are each provided with an active starting bed for accelerating the breakdown of the material supplied to each inclined plane, and that the lower edge of the second inclined plane is located above the first inclined plane, so that material which has been broken down or is in the process of being broken down on the second inclined plane can drop onto the material on the first inclined plane and participate in the continued breakdown of this material.

With a composting arrangement of this type, the container capacity is utilized considerably more efficiently than in previous arrangements, since the volume above the outlet end for compost earth is also employed for composting purposes. This means that it is possible either to increase the capacity of the arrangement or to use smaller containers, which reduces the space requirement and the manufacturing and transport costs of the arrangement.

In contrast to the arrangement according to SE 376229, a composting arrangement according to the invention can have two toilet bowls connected to one and the same composting container. Night-soil, that is to say a mixture of faeces and urine, is in this case supplied separately to two composting heaps under each respective toilet bowl. These heaps are in each case supported by an inclined plane, one of which is located above the other. Both inclined planes are provided with a starting bed and the night-soil is therefore broken down on both planes. After a period of use, material which has been broken down or is in the process of being broken down will drop from the upper plane onto the composting bed on the lower plane and participate in the continued breakdown of this material.

It is preferable for the first opening in the top surface of the container to be located above the highest end of the lower inclined plane, and for the second opening to be located above the highest end of the upper inclined plane.

The second inclined plane expediently ends with a transverse edge in order to hold the compost bed in place, which edge is in this case provided with openings for liquid, which runs down and wets the bed lying underneath. If appropriate, the upper inclined plane can be designed with openings for passage of liquid arranged along a large part of its length, for spreading the liquid across the underlying bed.

It is preferable for the upper inclined plane to extend over at least half of the length of the container, preferably over 2/3 of the length. In this way, if the material dropping has not been completely broken down, it has sufficient time to be broken down before reaching the outlet opening at the lower end of the lower inclined plane.

The container is expediently designed in two parts, with a bottom part and a top part, which makes manufacture and transport simpler and less expensive, and makes it easier to install a starting bed and to replace a destroyed compost bed with a new one. The inclined plane can in this case be secured at the transition between these parts. Further features of the invention are given in the patent claims .

The invention will be described in greater detail below with reference to the embodiment which is shown as an example in the attached drawings.

Fig. 1 is a diagrammatic illustration of a composting arrangement modified in accordance with the invention.

Fig. 2 is a longitudinal cross section through the arrangement in Fig. 1.

The arrangement shown in the drawing comprises a two-part composting container comprising a lower part 1 and an upper part 2. Inserted in the lower part 1 there is, in a conventional manner, an inclined plane 3 which extends over the entire length of the container. Alternatively, the bottom of the container can have an inclination.

When the arrangement is being set up, a starting bed 4 of compost earth or the like with the necessary bacteria and maggots is first placed on the inclined plane 3. This is made easier by the fact that the container is divided in two, as the whole of the inclined plane 3 can then be made accessible.

Above the highest end of the inclined plane 3, an opening 5 is arranged in the top surface of the container 'for connection to a toilet bowl or the like. Reference number 16 designates a ventilation channel, which expediently comprises a fan. The degradable material supplied via the opening 5 forms a heap 6 whose height varies depending on the frequency of use. In order to cope with peak loads too, the container must be relatively high. The material supplied is broken down with time, and the volume is thereby reduced. This is reflected in a decreasing thickness of the layer of composting material in the direction of the lower end of the inclined plane 3, where the final compost earth is removed.

Liquid which is separated off from the material is allowed to pass through a screen arrangement 7 to a collection housing 8, from which it can be conveyed, for example, to one or more tanks 9 arranged under the container 1 , 2 or diverted to a tank located outside the toilet unit, for example via a further composting bed.

The above represents known technology.

To achieve better utilization of the volume in the container 1, 2 above the compost bed near the outlet end, i.e. above the lowermost end of the inclined plane 3, the present invention proposes that a further inclined plane 10 be arranged above the plane 3 and with an inclination opposite to that of the other one.

The plane 10 is arranged with its highest end below a second opening 11 in the top surface of the container part 2, which opening is also intended to be connected to a toilet bowl or the like. The plane 10 is also provided with a starting bed 12 for accelerating the breakdown of the degradable material 13 which is supplied via the opening 11. The material 13 is broken down and reduces in volume while moving towards the lowermost end of the plane 10.

In order to hold the starting bed 12 in place, the plane 10 is designed with an upright edge 14 along the lower end. The edge is expediently provided with openings 17 to allow separated-off liquid to run down and wet the material lying underneath on the plane 3. Alternatively, the plane 10 can be provided with openings along the greater part of its length in order to spread the liquid over the material on the plane lying underneath.

Completely or partly broken down compost material will drop from the lower end of the upper inclined plane 10 onto the layer of material lying underneath on the plane 3 , and the process continues with the material moving towards the outlet end of the container.

In this way it is possible to lengthen the total distance which the material has to travel before reaching the outlet end, which means that it is possible to achieve complete breakdown of the said material. Moreover, the invention means that the otherwise unused volume in the container, above the outlet end, is used for composting purposes.

As is shown, the arrangement can be adapted to serve two toilets. Alternatively, it is possible to use only one toilet bowl connected to the opening 11, the plane 10 being in this case lengthened so that it reaches almost to the opposite wall of the container. This affords a very long breakdown distance, which among other things is advantageous for converting supplied urine to a liquid nutrient.

The plane 10 should be provided with side edges or be connected to the side walls of the container, so that material cannot drop onto the underlying plane from along the edges of the plane 10. An air gap 15 is also formed between the rear part of the plane 10 and the adjacent container wall in order to permit the necessary circulation of air in the container.

It is preferable for the plane 10 to extend at least over half the length of the container 1, 2, preferably over about 2/3 of its length.

In the drawing, the plane 10 has only been shown diagrammatically. In the case of a two-part container, it is expediently secured at the transition between the two parts or, if these are divided by a separately inserted raised part, between this part and one container part. The raised part can also be designed with inner mounting rims for the extra plane. To permit use of a container with thin walls, the container parts can be designed with reinforcing corrugations or the like, and these can be used for supporting the extra plane 10.

The invention has been described above with reference to the embodiment shown in the drawing. However, it can be varied in several respects within the scope of the patent claims. Thus, the principle of an extra, upper inclined plane can be used in all types of composting arrangements independently of the exact shape of the container.

Claims

PATENT CLAIMS

1. Composting arrangement for night-soil and other degradable material, comprising a container (1, 2) with a first inclined plane (3), arranged in the lower part (1) of the container, for receiving material which is to be broken down from a toilet bowl or the like, which is connected to an opening (5) arranged in the top surface of the container, and a second inclined plane (10) which is located above the first plane (3), characterized in that the second inclined plane slopes in the opposite direction to the first one, in that the top surface of the container is designed with a second opening (11) for connection to a second toilet bowl or the like, from which material which is to be broken down is supplied to the second inclined plane, in that the two inclined planes are each provided with an active starting bed for accelerating the breakdown of the material supplied to each inclined plane, and in that the lower edge of the second inclined plane is located above the first inclined plane, so that material which has been broken down or is in the process of being broken down on the second inclined plane can drop onto the material on the first inclined plane and participate in the continued breakdown of this material.

2. Arrangement according to Claim 1, characterized in that the first opening (5) in the top surface of the container (1, 2) is located above the highest end of the lower inclined plane (3), and in that the second opening (11)- is located above the highest end of the upper inclined plane (10) .

3. Arrangement according to Claim 1 or 2 , characterized in that the upper inclined plane (10) ends with a transverse edge (14) with openings for liquid.

4. Arrangement according to any of Claims 1 to 3 , characterized in that the upper inclined plane (10) is designed with openings for passage of liquid arranged along a large part of its length.

5. Arrangement according to any of Claims 1 to 4, characterized in that the upper inclined plane (10) extends over at least half of the length of the container (1, 2), preferably over about 2/3 of the length.

6. Arrangement according to any of Claims 1 to 5, characterized in that the upper inclined plane (10) is designed with side edges or is connected to the side walls (1, 2) of the container (1, 2) so that material is prevented from dropping down along the side edges of the plane.

7. Arrangement according to any of Claims 1 to 6, characterized in that a ventilation gap (15) is arranged between the wall of the container and the highest end edge of the upper inclined plane (10) .

8. Arrangement according to any of Claims 1 to 7, comprising a two-part container with a bottom part and a top part (1, 2) , characterized in that the upper inclined plane (10) is secured at the transition between these parts (1, 2) .

9. Arrangement according to any of Claims 1 to 8, characterized in that the container (1, 2) is provided with a screen arrangement (7) and a liquid outlet line at the lowermost end of the lower inclined plane (3).