WO2011048475A1

WO2011048475A1 - Plant and process for the production of energy from biomass

Info

Publication number: WO2011048475A1
Application number: PCT/IB2010/002688
Authority: WO
Inventors: Mauro Salvini
Original assignee: Idroelettrica S.R.L.
Priority date: 2009-10-22
Filing date: 2010-10-20
Publication date: 2011-04-28
Also published as: ITFI20090226A1

Abstract

Plant for the production of energy from biomass, comprising a boiler in which material formed by used equestrian bedding is burnt, and comprising, upstream of the said boiler, a tank (1) destined to receive the material to be treated and in which there are positioned means (3) for conveying said material to a crushing station located downstream and in which means (5) are provided for the reduction of the material into elements of predetermined size, means (8; 80) for conveying the crushed material to a drying station downstream, and means (12) for conveying the crushed and dried material from said drying station to said boiler.

Description

TITLE

Plant and process for the production of energy from biomass

DESCRIPTION

The present invention relates to a plant and to a process for the production of energy from biomass.

In particular, the present invention is advantageously useful for the production of energy from used equestrian beddings.

It is well known that in the equestrian centres, the disposal of used beddings is a heart felt problem under many aspects.

In fact, under many legislations, used beddings which are disposed externally to the equestrian centre are classified as waste and cannot be recovered, nor even as agricultural amender. As a consequence of this, the equestrian centre is forced to bear heavy expenses for said waste disposal.

Moreover, the high quantities to be stocked need spaces that could be used in an economically more advantageous manner and the equestrian centre is forced to foresee the use of suitable means and internal infrastructures for handling said material.

Besides this, the accumulation of dejections causes an uncontrolled proliferation of insects and of bacterial species which are harmful for the health of animals and men, in addition to the exhalation of smells which, under particular hygrometric conditions, can be very disagreeable .

The main aim of the present invention is to eliminate or at least to reduce said drawbacks.

These results have been achieved, according to the present invention, by adopting the idea of realizing a device and of carrying out a process having the features described in the independent claims. Further characteristics of the present invention are the subject of the dependent claims.

Thanks to the present invention, it is possible to overcome the drawbacks mentioned above and to simplify the management of an equestrian centre, both in terms of logistics and in terms of hygiene. Moreover, a plant according to the present invention is relatively easy to build, reliable and economical if compared to the advantages it offers.

Every technician who works in this field will better understand these advantages and further advantages and features of the present invention thanks to the present description and. to the enclosed drawings that are given by way of example and should not be seen in a limitative sense, wherein :

Fig.l shows a schematic side view of a plant according to the present invention ;

Fig.2 shows a schematic plan view of the plant of Fig. 1;

Fig.3 shows a schematic cross- section view of the plant of Fig. 1 in correspondence of the collection tank for the material to be treated;

Fig.4 shows a schematic cross-section view of the plant of Fig. 1 in correspondence of the first lifter and of the crusher;

Fig. 5 shows a schematic cross-section view of the plant of Fig. 1 in correspondence of the dryer,-

Fig.6 shows a schematic cross-section view of the plant of Fig. 1 in correspondence of the lifter which extracts the treated material;

Fig.7 shows a detail relative to the bottom of the collection tank for the crushed material;

Fig. 8 shows a detail relative to the dryer;

Figs. 9, 10 and 11 show a side view, a cross- section view and a detail of a plant according to a further embodiment of the plant .

Reduced to its essential structure and with reference to the figures 1 to 8 of the enclosed drawings, a plant according to the present invention comprises a collection tank (1) with a mobile roof (2) into which the material to be treated is introduced. The roof (2) can be, for example, a horizontal sliding roof as indicated by the double arrow "S" in Fig.l. The material which is introduced into the tank (1) is composed of used equestrian beddings.

Said collection tank (1) is advantageously a trapezoidal cross section tank, with a wall (PI) which forms a slide for guiding the material to an underlying horizontal screw-feeder (3) that is parallel to said wall (PI) in correspondence of the lower side thereof .

Preferably, said screw-feeder (3) is a coreless screw- feeder to facilitate the handling of the material without any hindrances.

The end portion of the screw-feeder (3) is in an extension (Tl) of the tank (1) . In other terms, the tank (1) exhibits an output section with the end portion of the screw-feeder (3), so the material introduced in the tank is guided, by the conveyor (3), in said end portion (Tl) of the tank (1) where there is installed a toothed lifter (4) which lifts the material fed by the conveyor (3) to transfer it to the hopper (T5) of a superjacent crusher (5) .

Said lifter (4), in practice, constitutes the end wall of the tank (1) through which the material destined to the crusher (5) exits.

The material coming from the tank (1) and handled by the screw-feeder (3) and by the lifter (4) is crushed in the crusher (5), so as to assume a relatively homogeneous size and so as to allow the subsequent drying phase to take place more regularly.

For example, the material exiting the crusher (5) can be of a size between 0.5 cm and 10 cm and, preferably, between 2.0 and 3.0 cm.

The output section of the crusher (5) is intercepted by a fixed metal sheet (6) which guides the discharge of the crushed material to an underlying collection tank (7). The latter exhibits an opening in correspondence of its bottom, where the portion of a second lifter passes (8) and transfers the crushed material from the tank (7) to the dryer described in the following. Fig.7, where the arrow "AT" indicates the forward direction of the teeth (D8) of the lifter (8) and, consequently, of the crushed material (7) , shows a constructive detail of the latter: a part of the wall (P7) is hinged around a horizontal axis to facilitate the de-compacting and the trimming of the crushed material which is moved away from the tank

(7) . In practice, the material handled from the lifter

(8) which moves forward along the direction "AT" is intercepted by said mobile part of the wall (P7) which, being free to rotate, as indicated by arrow "F7", works with its lower edge so as to trim the exiting crushed material which consequently assumes a more uniform thickness. This process facilitates the subsequent drying of the material under treatment.

The material removed from the tank (7) by means of the lifter (8) is transported to a dryer (9) . The latter, according to the proposed embodiment, comprises a conveyor formed by perforated overlapped webs (N9) which is positioned between and underlying burner (10) and an exhaust fan overhead (11). The webs (N9) are wound around pulleys (P9) which delimit a path whose length is sufficient to allow the permanence of the material inside the thermal flux produced by the burner (10) for a time sufficient to allow the drying of the material. Moreover, said conveyor comprises a plurality of brushes (S9) which act on the corresponding webs (N9) so as to clean them.

For example, the drying station for the crushed material can be dimensioned to allow the extraction of 0.05 ÷ 0.10 kg of H₂0 per minute per each kilogramme of treated biomass.

Moreover, for example, the hot air coming from the burner (10) and directed perpendicularly to the forward direction of the material imposed by the webs (N9), can be at a temperature between 25°C and 50°C, preferably 40°C, with a speed between 0.5 m/sec and 2.0 m/sec, preferably 1.0 m/sec.

The dried . material exits the dryer (9) and falls onto the teeth of a third lifter (12) which transports the material to a boiler downstream (not shown in the drawings) where the material is burnt to produce thermal energy.

The produced energy can be used, for example, for internal requirements of the equestrian centre (production of hot water, production of steam and so on) , and, if it exceeds the requirements of the equestrian centre, it can be provided to external consumers .

In this way, it is possible to solve the problem of the disposal of used beddings an economically logistically and hygienically advantageous manner.

The equipment described above can be contained in a pre-assembled module (M) such as container, for example. For instance, the equipment for treating the material can be contained in a first container and the boiler can be contained in a second container adjacent to the first one.

In the plant described above there takes place a process which comprises the following operative steps transportation of the material to be treated to a crusher in which the material is reduced to elements of predetermined size ;

transportation of the crushed material to a dryer in which the crushed material is dried until it achieves a predetermined degree of humidity;

transportation of the dried material to a boiler in which the dried material is burnt to produce thermal energy .

The same process can take place in the plant shown in Fig 9 and in fig.10, in which, to transport the material from the tank (1) to the crusher (5), it is possible to use only the screw-feeder (3) which is conveniently disposed in an inclined position, with one side (30) which plunges into the bottom of the collection tank (1) and one side (31) which discharges the material on the crusher(5). The latter, according to the embodiment shown in Fig.9 and in Fig.10 and in the details of Fig.11, consists of a drum (100) with a surface provided with toothed rings (101) cooperating with oscillating blades (102) mounted on an additional drum (103) which moves said blades by rotating them around an axis which is parallel to the axis of the first drum (100). The crushed material is then transported to the dryer (9) by a screw-feeder (80) instead of being transported by the lifter (8) described above. Upperly to the drum (100) there is mounted a sliding gate (104) by means of which it is possible to adjust the quantity of material transferred to the crusher (5) .

In practice, the construction details may vary in any equivalent way as regards the shape, dimensions, disposition of elements, nature of the used material, without nevertheless departing from the scope of the adopted solution idea and thereby remaining within the limits of the protection granted to the present patent.

Claims

1) Plant for the production of energy from biomass, comprising a boiler in which material formed by used equestrian bedding is burnt, characterized by the fact that it comprises,, upstream of the said boiler, a tank

(1) destined to receive the material to be treated and in which there are positioned means (3) for conveying said material to a crushing station located downstream and in which means (5) are provided for the reduction of the material into elements of predetermined size, means (8; 80) for conveying the crushed material to a drying station downstream, and means (12) for conveying the crushed and dried material from said drying station to said boiler.

2) Plant according to claim 1 characterized by the fact that the said conveying means (3) comprise a coreless screw-feeder positioned and acting on the bottom of the said tank (1) .

3) Plant according to claim 1 characterized by the fact that it further comprises means (4) for handling the said material from the tank (1) to the crushing means (5), with a lifter (4) located and acting in an extension (Tl) of the said tank (1) and which lifter (4) transfers the material fed by the screw-feeder (3) towards hopper (T5) for the loading of the crushing means ( 5 ) .

4) Plant according to one or more of the previous claims characterized in that the said crushing means (5) discharge the crushed material into an underlying collection tank (7) cooperating with said means (8) for conveying the crushed material to the drying station.

5) Plant according to claim 4 characterized by the fact that between an output section of the crushed material from said crushing means (5) and the said tank (7) there is positioned an element (6) that guides the discharge of crushed material in the same tank ( 7 ) .

6) Plant according to one or more of the previous claims characterized in that in said drying station there is a dryer (9) comprising a conveyor formed by perforated overlapped webs (N9) and positioned between an underlying burner (10) and an overhead exhaust fan (11) -

7 ) Plant according to claim 6 characterized by the fact that said conveyor (9) comprises a plurality of brushes (S9) destined to clean the said webs (N9) .

8) Plant according to claim 1 characterized in that the said means for conveying the crushed material towards the drying station comprise a screw-feeder (80) .

9) Process for the production of energy from biomass, comprising a step in which a material formed by used equestrian bedding is burnt, characterized in that it comprises the following operative steps:

- transportation of the material to be treated to a crusher where it is reduced into elements of predetermined size;

- transporting the crushed material to a dryer in which the crushed material is dried to achieve a predetermined moisture content;

- transporting the dried material to a boiler in which the dried material is burned to produce thermal energy.