WO2003076349A2

WO2003076349A2 - Plant and method for the disposal of zootechnical sewage

Info

Publication number: WO2003076349A2
Application number: PCT/EP2003/002294
Authority: WO
Inventors: Luigi Candiracci; Francesco Candiracci
Original assignee: Candiracci Luigi & C SNC
Current assignee: Candiracci Luigi & C SNC
Priority date: 2002-03-08
Filing date: 2003-03-06
Publication date: 2003-09-18
Anticipated expiration: 2004-09-08
Also published as: ES2370241T3; EP1490305B1; EP1490305A2; AU2003240442A8; ATE517848T1; ITBO20020122A0; ITBO20020122A1; WO2003076349A3; AU2003240442A1

Abstract

A plant for the treatment of zoo-technical sewage includes: a basin (2), intended to accommodate the sewage and a material of vegetable origin (100) in a minced form; stirrers (6) and aerators (8) for the material of vegetable origin (100), impregnated with the sewage and associated stuff in basin (2). Said stirrers (6) being adapted to cause the material of vegetable origin (100) to be mixed with the sewage to form a homogeneous biomass which is, in turn, mixed; said aerators (8) being adapted to blow in air into the biomass, thus helping it to be dehydrated and fermented.

Description

PLANT AND METHOD FOR THE DISPOSAL OF ZOOTECHNICAL SEWAGE

Field of the Invention

The present invention relates to the technical field of plants intended for the disposal of organic sewage and, in particular, this invention relates to a plant and a method for the disposal of liquid zoo technical sewage deriving, e.g., from the faeces and urines of swine and similar animals. The disposal of sewage that is produced at swine or other animals' stock farms is presently carried out by means of cleaners wherein the liquid mass, discharged into basins or containers of appropriate sizes, is relentlessly stirred to eliminate ammoniac and other volatile polluting substances. Later, the solid components are separated from the liquid ones in order to use said solid components as manure. The residual liquid components are scattered all over the ground, which must feature suitable crops and an adequate surface area. Background Art Disposal methods are also known to include sewage accumulation in stocking lakes from which this material is later drawn and scattered all over the ground during allowed periods. The main disadvantage of this equipment and these known procedures is that wide ground extents are needed on which the liquid sewage component is to be scattered. These grounds must be grown with suitable crops, be located far from watercourses or water beds that could be polluted by the said sewage as well as from residential centres on account of the exhaled stench. Another drawback is ground saturation within short periods, which causes the ground to be made unable to bear and absorb organic liquids any more. Sewage disposal is also carried out through the adoption of animal sheds fitted with an outwards slanting floor with straw-covered litters. In this case the outwards-draining sewage is collected with a scraper and reused.

The main drawback with this method is that it requires rarely available particular sheds with draining floors and the straw used, that gets dirty without maturing, cannot be used as manure and is to be disposed of, this involving difficult and expensive disposal procedures.

Another drawback with the above-described equipment and methods is that they generate miasmas and bad, particularly nasty smells.

Objects and Summary of the Invention

The main object of this invention is to propose a plant and a method for the disposal of zoo technical sewage, in particular coming from bred swine, and therefore dispensing with dangerous and expensive lakes or ample sewage collecting basins and extended ground plots with adequate characteristics.

Another object is to propose a plant and a method allowing sewage treatment without the use of additional chemical matters capable of turning the sewage into a mixed, stable and natural conditioning compound ready for use in the fertilization of agricultural crops and practically free of nasty smells.

Still another object is to propose a plant and a method offering a high cost-effective efficiency and performance.

Therefore, the problems and limitations of prior art plants and methods are overcome by a plant having the features disclosed in claim 1 and by a method having the steps disclosed in claim 27.

Brief description of the Drawings

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further objects and advantage thereof, may be understood with reference to the following description, taken in conjunction with the accompanying drawings, and in which:

- figure 1 shows a schematic plan view of the plant for the treatment of organic sewage, the subject of this invention;

- figure 2 shows an enlarged, partial and sectional plan view of elements of the plant as shown in figure 1 ; - figure 3 shows a sectional front view of the elements as shown in figure 2;

- figure 4 shows a sectional side view of the elements as shown in figure 2;

- figure 5 shows an enlarged side view of the stirring means shown in figure 1, wherein some parts have been removed in order to better emphasize other parts;

- figure 6 shows a front view of the stirring means as shown in figure 5; - figure 7 shows a plan view of the stirring means as shown in figure 5;

- figures 8 and 9 are front and plan views, respectively, of a plant featuring several basins, and

- figure 10 shows a plan view, to an enlarged scale, of the bridge crane translation means among the different basins in the plant as shown in figures 8 and 9. Brief description of a preferred embodiment of the Invention

With reference to figures 1 through 7, 1 denotes the plant for the treatment of zoo technical sewage, which is the subject of this invention. The plant i&basi -δrlly made up of a basin 2 intended to accommodate the sewage and one or more materials of vegetable origin in a shattered form, either accompanied or not by materials of organic origin, stirring means 6 and aerating means 8 associated to the basin 2. The plant included a bridge crane 3 translating on first guide means 21 of basin 2 and is fitted with sewage inlet means 4 into basin 2.

The first guide means 21 consist of a couple of rails, each of which is fastened to its related longitudinal edge of basin 2 to support a multitude of wheels 30 of bridge crane 3, two of these wheels being driven, through the first transmission means 33, by the first actuator means 32 fastened to bridge crane 3. It is also possible to adopt an integral drive for bridge crane 3, for instance through the use of a drive chain system 34 transmitting the motion of the wheels driven by the first actuator means to the remaining wheels. Sewage inlet means 4 consist of a dispenser 41, featuring a lengthened shape and fastened on a cross edge of bridge crane 3 and internally fitted with stirring means 42 to stir the sewage and discharge it through a lengthwise opening 43 in the above- mentioned dispenser 41. This dispenser 41 is about as long as the width of bridge crane 3, and stirring means 42 consist of an axle fitted with several fins, driven by third actuator means 44.

The plant includes a trolley equipment 5 , slidably supported by second guide means 37 of bridge crane equipment 3, and slidably supports stirring means 6 and aerating means 8. Trolley equipment 5 includes first translation means 52, slidably coupled with second guide means 37 of bridge crane equipment 3 and third transmission means 54 for operating trolley equipment 5 with respect to bridge crane 3.

First translation means 52 include a multitude of idle wheels 53 of trolley equipment 5 that match the rails of second guide means 37. Third transmission devices 54 include a couple of pinions 55 driven by second actuator means 51 connected to their related rack means 24 of bridge crane 3.

Stirring means 6 and aerating means 8 are fastened to saddle means 9 that are translated by fourth transmission means 57 through fourth actuator means 58 of trolley equipment 5 between a lifted condition A and a lowered condition B, wherein stirring means 7 and aerator means 8 are lifted and lowered, respectively, with respect to basin 2.

Fourth transmission means 57 consist of a worm screw 59 which is started rotating by the fourth actuator means 58 and is connected to a related nut screw 61 fastened to saddle means 9. The latter include second translation means 62 fitted with a multitude of idle rolls 63 that are engaged into corresponding rails of third guide means 56 of trolley equipment 5.

Stirring means 6 consist of five shafts 67, each of which is fitted with a multitude of blades 68 and is set rotating around its own axis by fifth actuator means 66 through fourth transmission means 65 of saddle means 9. Blades 68 are preferably arranged helically along their own related shaft 67.

Fourth transmission means 65 include a multitude of gear wheels 64 linked to one another, each of which being fastened onto a shaft 67 of its own; one of these shafts is linked to fifth actuator means 66. Shafts 67 are reciprocally parallel and arranged on a plane that is brought to the longitudinal edges of basin 2. Aerator means 8 include a multitude of ducts 70, each of which is fitted with at least one air discharge outlet 72. In the preferred embodiment, each duct 70 is obtained in a related shaft 67, which in this case is a hollow tube, and discharge outlets 72 are realized matching the free end of said shaft 67 according to a radial arrangement. Provision is made for first guide means 21 and second guide means 37 to be at right angles to shafts 67, so that stirring means 6 and aerator means 8 can be shifted along three axes perpendicular to one another. Actuator means 32, 51, 44, 58, 66 consist, each of them, of an electrically-, pneumatically- or hydraulically-driven rotary motor. Basin 2 is, for instance, made of reinforced concrete, has a rectangular shape and a longitudinal drainage conduct is built into the basin bottom. Basin 2 is, for instance, between 1.00 and 1.50 m deep, between 25 and 150 m long and between 5 and 20 m wide.

The plant also includes a roof intended to wholly cover basin 2 and protect it against meteoric rains. Material 100 consists: a) in its entirety, of components of vegetable origin such as straw, rice chaff, chopped portions of maize wastes, sunflower and wheat, wooden shavings, sawdust, and leaves, preferably a mix of these components, or b) of components of vegetable origin mixed with components of organic origin; straw may, for instance, be got from stable litter and later mixed with organic components.

Provision is made for the plant to be entirely interlocked with electronic computing and control devices consisting of a PLC or a personal computer, capable of supervising phase relations at least among the bridge crane equipment 3, the trolley equipment 5, inlet means 4, stirring means 6, aerator means 8 and actuator means 32, 51 , 44, 58, 66. A manual operation mode is also possible.

Plant operation also includes operating bridge crane equipment 3 along basin 2 to uniformly scatter sewage onto material of vegetable origin 100 and running to and fro along the basin until the above-mentioned material 100 is fully impregnated with sewage.

Stirring means 6 and aerator means 8 are put inside the basin 2 and translate saddle 90, to which they are fastened, from a lifted condition A to a lowered condition B. At this point stirring means 6 are set rotating by the fourth actuator means 66 to get the material of vegetable origin 100 mixed with sewage and forming a stirred homogeneous biomass.and reshuffle the latter. Aerator means 8 are linked to an appropriate generator and blow air into the biomass to help its dehydration and fermentation. During stirring and aeration operations, stirring means 6 and aerator means 8, integral with trolley equipment 5, are progressively translated along straight- line directions over the whole extension of basin 2. In a more precise manner, bridge crane device 3 is translated in an alternate motion along the whole length of basin 2 through stops and predefined-length advances; when bridge crane equipment 3 is advancing, trolley equipment 5 is stationary. The latter, in turn, is translated throughout the length of basin 2 during each stop by bridge crane equipment 3. Once bridge crane 3 has covered the whole length of basin 2, it can be translated to its initial position while, at the same time, letting in new sewage into the basin.

If necessary, the biomass stirring and aeration procedure can repeated one or several times. Stirring and aeration operations are stopped after a given time interval which is needed at least for a partial biomass degradation through enzymatic and biological degradation processes for at least a partial transformation of the biomass into a stable compost substance.

Figures 8 through 10 show a plant featuring several basins - which, for instance, could be arranged side-by-side, two of which, identified with 2a, 2b, are shown in the figure. In this case bridge crane 3, together with sewage inlet means (not shown in these figures) and trolley equipment 5, is installed on shifting means 10 that are shifted along third guide means 11, e.g. rails, fastened on a bedplate 20 extending in front the range of basins 2a and 2b and supporting a multitude of wheels 12 of shifting means 10 . Provision is made on the upper face of shifting means 10 for fourth guide means 13 to which wheels 30 of crane bridge equipment 3 are engaged. The movements of shifting means 10 are obtained with fifth actuator means 14, for instance a couple of electrically-, hydraulically- or pneumatically-driven motors coupled to two of wheels 12. Provision is also made for electric feed cable winding means 15 during movements of shifting means 10. Winding means 15 are driven by sixth actuator means 16. Shelters 17, together with their related supports 18 covering basins 2a and 2b, and stair flights 19 enabling access to collecting means for the treated sewage are also shown.

The invention's operation in the case for a plant featuring several basins can be immediately drawn from what is described above. Shifting means 10 together with bridge crane 3 are initially stationed connected to the first basin, e.g. basin 2a, fourth guide means 13 aligned with first guide means 21 of said basin. Bridge crane 3 is then shifted along basin 2a, and the above-described treatment cycle is carried out. At the end of this cycle, bridge crane 3 is shifted back on shifting means 10 which are therefore shifted along third guide means 11 and brought to be connected with second basin 2b. When the treatment process in the second basin has been completed, operations will be continued in the same way for any subsequent basin.

The method for the treatment of zoo technical sewage, which is the subject of this invention, by means of a plant 1 including at least a basin 2, stirring means 6 and aerator means 8, makes provision for:

- letting into basin 2 material of vegetable origin 100 in a fragmentized form, or components of vegetable origin mixed with components of organic origin;

- providing an even scattering of said sewage on material 100 until the latter has been fully impregnated so that a biomass is obtained;

- imparting movement to the biomass through stirring means 6;

- aerating the biomass through aerator means 8; - stopping the stirring and aeration operations after a given time interval, as needed until at least a partial biomass degradation through enzymatic and biological aerobic degradation processes has been achieved for at least a partial transformation of the biomass into a stable compost substance;

- extracting the said compost substance from basin 2. This method makes provision for an even sewage scattering on material (100) all over the basin 2 extension to be periodically repeated for as many times as necessary, for instance, between one and three times per day. The biomass stirring and aeration operations are progressively carried out along straight-line directions over the whole extension of basin 2. The method makes provision for stirring ajvd aerating operations on the biomass at the same time and to extract from basin 2 the compost substance after reaching a pre-defined dehydration value of the same substance. In case several basins are used, this method is to be repeated identically for all basins. Provision is made, in order to obtain the material 100, to make use of such vegetable components as straw, rice chaff, chopped portions of maize, sunflower, wheat, wood shaving, sawdust and leaves; preferably a mix of such components, either combined or not, with materials of organic origin.

The main advantage of this invention is to provide a plant and a method for the treatment of zoo technical sewage while dispensing with lakes or extended sewage- collecting basins as well as extended ground plots with adequate features. Another advantage is to provide a highly efficient and yield plant and cost-effective method allowing sewage to be processed without the use of additional chemical substances capable of converting the sewage into an amending stable mixed compost which can be immediately used for the fertilization of agricultural crops and is virtually smell-free. While a particular embodiment of the present invention has been shown and described, it should be understood that the present invention is not limited thereto since other embodiments may be made by those skilled in the art without departing by the object of the present invention. It is thus contemplated that the present invention encompasses any and all such embodiments covered by the following claims.

Claims

1) A plant for the treatment of zoo technical sewage, characterised in that it includes: a basin (2, 2a, 2b) intended to accommodate the sewage and one or more materials (100) of vegetable origin in a fragmentized form, possibly combined with materials of organic origin; stirring means (6) and aerator means

(8) for the materials) (100) impregnated with sewage and associated to at least one basin (2, 2a, 2b); said stirring means (6) being adapted to cause the material(s) (100) to be mixed with the sewage to form with the latter a homogeneous biomass and reshuffling of the same; said aerator means (8) being adapted to blow air into the biomass to help it being dehydrated and fermented.

2) A plant according to claim (1), characterised in that it includes a bridge crane equipment (3) which translates on first guide means (21) of basin (2) and fitted with sewage inlet means (4) into at least one basin (2, 2a, 2b). 3) A plant according claim 2, characterised in that it includes a trolley equipment

(5) slidably supported by second guide means (37) of bridge crane equipment (3) and slidably supporting stirring means (6) and aerator means (8).

4) A plant according to claim (2), characterised in that each longitudinal edge of at least one basin (2, 2a, 2b) is provided with a rail of first guide means (21) for a multitude of wheels (30) of bridge crane equipment (3).

5) A plant according to claim 4 characterised in that at least one of wheels (30) is driven, through first transmission means (33), by first actuator means (32) of bridge crane equipment (3).

6) Plant according to claim 2 characterised in that sewage inlet means (4) which include at least a dispenser (41) with an elongated shape, fastened to a transverse edge of bridge crane equipment (3) and internally fitted with stirring means (42) to handle and drain away the sewage through a longitudinal opening (43) of said dispenser (41).

7) Plant according claim 6 characterised in that dispenser (41) is almost as long as the width of bridge crane equipment (3).

8) Plant according to claim 6 characterised in that stirring means (42) include an axle fitted with a multitude of fins which are rotated by third actuators (44).

9) Plant according to claim 3 characterised in that a trolley equipment (5) that includes second guide means (37) of bridge crane equipment (3) and third transmission means (54) in order to move trolley equipment (5) with respect to bridge crane equipment (3).

10) Plant according to claim 9 characterised in that first translation means (52) that include a multitude of idle wheels (53) of trolley equipment (5) matching the rails of the second guide means (37); third transmission means (54) include at least one pinion (55) driven by second actuators (51) and linked to the related rack means (24) of bridge crane equipment (3).

11) Plant according to claim 3 characterised in that stirring means (6) and aerator means (8) are fastened to saddle means (9), translated by means of fourth transmission means (57) by fourth actuator means (58) of trolley equipment (5) between a lifted condition (A) and a lowered condition (B), respectively, wherein said stirring means (7) and aerator means (8) are lifted and lowered, respectively, with respect to basin (2, 2a, 2b) upon which they are operating.

12) Plant according to claim 11 characterised in that fourth transmission means (57) include at least a worm screw (59) set rotating by fourth actuator means (58) and linked to a related nut screw (61) fastened to saddle means (9).

13) Plant according claim 11 characterised in that saddle means (9) including second translation means (62) fitted with a multitude of idle rollers (63) that are engaged into related rails of third guide means (56) of trolley equipment (5).

14) Plant according to claim 11 characterised in that stirring means (6) include a set of shafts (67), each of which is fitted with at least one blade (68) and put around its own axle by fifth actuator means (66) through fourth transmission means (65) of saddle devices (9).

15) Plant according to claim 14 characterised in that each shaft (67) includes a multitude of blades (68) helically arranged along said shaft (67). 16) Plant according to claim 14 characterised in that fourth transmission means (65) include a multitude of gear wheels (64) linked with one another and each of which is fastened to its related shaft (67). 17) Plant according to claim 4 characterised in that shafts (67) are mutually parallel and arranged in a plane brought to the longitudinal edges of basin (2). 18) Plant according to claims 2 and 3 characterised in that aerator means (8) include a multitude of ducts (70), each of wnieli is fitted with at least one outlet opening (72) for air discharge. 19) Plant according $o -claims 14 and 18 characterised in that each duct (70) has been obtained in a related shaft (67), and that outlet openings (72) are realized near he free end of said shaft (67). 20) Plant according to claims 2, 3 and 14 characterised in that first guide means (21) and second guide means (37) are arranged at right angles to shafts (67).

21) Plant according to any of the foregoing claims, characterised in that it includes a multitude of basins (2a, 2b) and shifting means (10) to bring bridge crane equipment (3), together with sewage inlet means (4) and trolley equipment (5) supporting stirring means (6) and aerator means (8), subsequently in relation_, to each basin (2a, 2b).

22) Plant according to claim 1 or 21, characterised in that a basin (2), or each basin (2a, 2b), has a longitudinal draining channel built into the bottom of basin (2) or each basin (2a, 2b).

23) Plant according to claim 1 or 21, characterised in that it includes a roof (17) as a covering for basin (2) or basins (2a, 2b).

24) Plant according to anyone of claims 5, 8, 10, 11 and 14 characterised in that actuator means (32, 51 , 44, 58, 66) consist of an electrically- or pneumatically- or hydraulically-driven rotary motor.

25) Plant according to claim 1 or 21 , characterised in that the material components of vegetable origin (100) include at least one or more components out of straw, rice chaff, chopped portions of maize wastes, sunflower, wheat, wood shaving, sawdust and leaves. 26) Plant according to claims 2, 3 and 21, characterised in that it is wholly interlocked with electronic computing and control equipment capable of supervising the phase relation at least among translating means (10), bridge crane equipment (3), trolley equipment (5), sewage inlet devices (4), stirring means (6) and aerator means (8). 27) A method for the biological treatment of zoo technical sewage by means of a plant (1) including at least a basin (2), stirring means (6) and aerator means (8), the said method being characterised by the combination of the following steps:

- introducing into a basin (2, 2a, 2b) one or more materials (100) of vegetable origin in a fragmentized form, possibly combined with materials of organic origin;

- evenly scattering this sewage over material(s) (100) until the latter is/are wholly impregnated to yield a biomass;

- getting the biomass stirred by means of stirring means (6);

- aerating the biomass by means of aerator means (8); - stopping the biomass stirring and aeration operations after a given time interval as needed at least so that a partial biomass degradation takes place through enzymatic and biological aerobic degradation processes for an at least partial conversion of the biomass into a stable compost substance; - extracting this compost substance from at least one basin (2, 2a, 2b). 28) The method according to claim 27 for a plant including a multitude of basins (2a, 2b), characterised in that the inletting, scattering, stirring and aerating steps involving the biomass, as well as the biomass extraction from each basin (2a, 2b) are repeated sequentially.

29) The method according to claim 27 or 28, characterised in that the even scattering of sewage over materials) (100) all over the extension of basin (2) or each basin is periodically repeated as many times as necessary, e.g. between one and three times per day.

30) The method according to claim 27 or 28, characterised in that the biomass is progressively set stirred and aerated along straight-line directions. 31) The method according to claim 27 or 28, characterised in that a biomass is mixed and aerated at the same time. 32) The method according to claim 27 or 28, characterised in that the compost substance is extracted from basin (2) after a pre-established dehydration value has been attained for said substance. 33) The method according to claim 27 or 28, characterised in that it makes use, as components of vegetable origin of the materials): straw, rice chaff, chopped portions of maize wastes, sunflower, wheat, wood shaving and sawdust, leaves or mixtures thereof.