WO2015173450A1

WO2015173450A1 - Equipment for breeding insect larvae and auxiliary systems

Info

Publication number: WO2015173450A1
Application number: PCT/ES2015/070364
Authority: WO
Inventors: Andres Fullana Font; Santos ROJO VELASCO; Paola GOBBI; Alfredo LLECHA GALIÑANES; Agustín LOZANO MORCILLO
Original assignee: Universidad De Alicante
Priority date: 2014-05-15
Filing date: 2015-05-06
Publication date: 2015-11-19
Also published as: ES2551280B2; ES2551280A1

Abstract

The invention relates to equipment for breeding insect larvae, comprising a larvae digestion reactor, with a supply system, an aeration system and a solid extraction system. The solid extraction system has an air stream introduced via the base of the reactor, solid-gas and solid-solid separators being arranged behind the reactor. The aeration system comprises an aeration conduit arranged in the lower part of the reactor, connected to the digestion chamber by means of a diffuser with a plurality of perforations along the digestion chamber. The supply system comprises a water and nutrient mixer and an extruder for extruding the sludge formed. The reactor can operate under hyperbaric conditions.

Description

BREEDING EQUIPMENT OF INSECT LARVES AND AUXILIARY SYSTEMS

DESCRIPTION

Breeding equipment for insect larvae and auxiliary systems.

TECHNICAL SECTOR The present invention relates to an insect larvae breeding equipment, for example dipterans, beetles and, in general, saprophagous insects, by means of hyperbaric conduits, which allows the conversion of organic waste into larval biomass, and that can be used later in human or animal feed or in the generation of compounds with industrial interest.

It also refers to auxiliary systems for feeding and extracting waste solids.

STATE OF THE TECHNIQUE

There are numerous advantages in the use of decomposing insect larvae for the processing of different organic substrates (eg agri-food by-products, sewage sludge, livestock waste, catering, urban, etc.), some of these advantages are:

1) Larvae can feed on organic matter of very diverse nature in large areas of the world.

2) They transform the organic compounds contained in the residues and by-products into proteins, fats and other bio-compounds with industrial interest.

3) Its high protein content has great nutritional value for use in animal and / or human nutrition. Although in the state of the art various equipment for artificial cultivation and mass production of decomposing diptera larvae have been proposed, one of the The main problems they present are the impossibility of their development in totally anaerobic conditions. Larvae cannot grow and feed properly on substrate thicknesses greater than 25 centimeters. That is why in some known equipment shallow trays ( ^« 10 cm) are used as devices for the development of larvae, as seen in US20130319334A1 (Larry Newton & Craig Sheppard." Systems and Methods for Rearing Insect Larvae ") or US201 10296756A1 (Mao Zhang. Mini Space Farm, "A Food Regenerative System in the Long-Term Space Mission"). These teams have the problem of poor use of space, the scaling of their production and the difficulty of harvesting the larvae at the end of the digestion of the substrate.

For the collection of the larvae, many teams incorporate ramps that allow the natural exit of the larvae allowing their self-harvesting. US20130319334A1 is cited again and US6579713B2 (Paul Olivier. "Apparatus for bio-conversion of putrescent wastes"). However, these methods are time consuming and do not improve biomass production per unit area. In addition, larvae often do not perform synchronous growth and development, so self-harvesting can last several days or weeks.

Some procedures include the use of forced air in rectangular or cubic devices (CN102499190A; "Ventilating and stirring type Hermetia illucens bioprocessor". ES2331452B2 ¹ FLYSOIL, SL "Equipment and process for the elimination of organic waste by insect larvae"). However, these devices operate continuously and they establish different gradients with larvae of different ages and multiple substrate supply.

On the other hand, the use of reactors (digesters) with a length / diameter ratio with a value less than 1, leads to less space utilization, hinders the supply of the substrate for larval development, as well as the extraction of the substrate modified by the larval activity and the larvae harvested. In addition, the use of gaseous streams at atmospheric pressure percolating through conventional means in which the larvae of the dipterans are fed is relatively inefficient, since the air is randomly blurred by the places where it finds less resistance. This fact does not completely solve the problems derived from areas with anaerobiosis, since there will be completely anaerobic areas randomly located in the food substrate that will be naturally avoided by the larvae. The present invention is aimed at solving the technical problems described above, by means of a novel insect larval breeding equipment and, in a second object of the invention, a plurality of auxiliary systems of said equipment.

BRIEF EXPLANATION OF THE INVENTION

The present invention thus relates to a breeding equipment for insect larvae, preferably saprophages (decomposers of organic substrates), for example dipterans or beetles. This equipment allows the development and collection of insect larvae using reactors composed of pipes that can work in hyperbaric regime. The invention also relates to systems for the provision of the food substrate and for the removal of solids containing waste and the larvae of the reactors of said equipment.

The present invention solves the aforementioned problems, its objective being the creation of a breeding equipment for diptera insect larvae as an integral system for the development and growth of organic matter decomposing diptera larvae, including the fattening and biomass collection stages.

The insects to which the system refers can be, for example, larvae of species of saprophagous dipterans of different families, mainly stratiomides (Stratiomyidae, eg Hermetia lllucens), symphids (Syrphidae, eg Eristalis tenax, Eristalinus aeneus) muscled (Muscidae eg Musca domestica) and caliporides (Calliphoridae, eg Calliphora vicina, Chrysomya megacephala, Lucilia sericata) although it can be applied to larvae of other families of organic matter decomposing dipterans, and also of beetles.

The texture of the organic substrate offered as food to the larvae of decomposing insects of organic matter is often a pasty solid that prevents its correct drive by conventional methods. That is why the present invention is aimed at generating a mixing and impulsion of sludge capable of providing a mixture of foods with a correct moisture content, which It allows to be transported inside large pipes. The present invention also includes means for the introduction of neonatal insects or larvae of small dipterans inside the reactors, by means of a drive system.

The problem of extracting solid components from larval digestion and retained in conductors of type reactors, in which their length / diameter ratio has a value greater than 1, is also solved in the present invention. This extraction takes advantage of the movement of the larvae inside the reactor and their mixing effect. Larval digestion causes over time that the food substrate is transformed into a solid with porous structure. That is why it is possible to extract the contents of the interior of the reactor by means of an air entrainment system composed of an air supply unit, the reactor itself that acts as a conduit and a solid-gas separation system that allows the collection of the mass formed by the undigested substrate, digested substrate and larval biomass. When this solid current is found with a low water content, it is possible to perform a separation by screening of the larvae and the other components.

The present invention also solves the problem of the development of larvae in substrates with thicknesses greater than 25 cm. This is possible thanks to the continuous injection of oxygen, which can be introduced into the system maintaining a hyperbaric pressure inside the reactor to optimize the larval digestion process in aerobiosis. Besides maintaining this hyperbaric pressure, it is possible to control the temperature and humidity of the substrate, so that they are adequate to guarantee the growth and fattening of larvae of the diptera.

This hyperbaric pressure is maintained by means of control arranged inside the reactor (for example valve systems), allowing a total oxygenation thereof, greatly increasing the survival of the larvae and accelerating their metabolism. The proposed system works in such a way that the substrate introduced into the reactor is assimilated by the larvae of the interior, being able to proceed to the addition of a new food substrate, if required, allowing its mixing with the substrate previously modified by the larval and microbial activity . The system is discontinuous and operates by loads of food. Once the larval development process has been completed, the interior of the reactor and the larvae can be extracted from the system for later use. Breeding equipment of decomposing insect larvae comprises a larval digestion reactor. In addition to the reactor, the equipment includes a feed system, aeration system and a solids extraction system.

The solids extraction system preferably operates by air flow, for which it comprises an air delivery system configured to generate an incoming air stream, and preferably introducing it into the base or bottom of the reactor. Once said air drags the solids (debris and larvae), then it takes an outlet pipe from the reactor. The entrained solids can be taken to a tank for subsequent treatment or, directly, to a solid-gas separator, followed by a second separator, in this case solid-solid to separate the larvae from the waste material. In particular, the aeration system preferably comprises an aeration duct, located at the base or bottom of the reactor, and is connected to the digestion chamber by means of a diffuser containing a plurality of perforations along the chamber of reactor digestion. The aeration duct can also function as an input of the solids extraction system.

The feed system will preferably be a mixer of a stream of water and a stream of nutrients that forms a sludge or paste and an extruder that introduces it into the reactor through a narrowing. In this narrowing, water or neonatal insects can be added in an additional stream.

Preferably, the equipment will comprise a hermetic reactor and a hyperbaric air or oxygen pressure system inside the reactor. This may have a pressure line that connects a pressure vessel or discharge equipment to the reactor, and as an optional safety measure, an internal pressure gauge to the reactor capable of acting on an exhaust or purge valve of the reactor. The pressure gas can be entered through the aeration duct.

The invention also relates to a solids extraction system and the feeding system independently, for application to larval breeding equipment of diptera or beetle insects. DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, the following figures are included: - Figure 1. Flow chart of the reactor filling process with nutrients and neonates.

Figure 2. Flow chart of the reactor content extraction process. - Figure 3. Scheme of a first embodiment of the reactor, of square section.

Figure 4. Scheme of a second embodiment of the reactor, of circular section.

Figure 5. Scheme of a third embodiment of the reactor, also of circular section.

Figure 6. Flow diagram of a reactor in hyperbaric conditions.

EMBODIMENTS OF THE INVENTION

A preferred embodiment of the invention will now be described, as an illustrative and non-limiting example thereof.

Figure 1 shows an embodiment of the feeding system, configured to provide mixing of the different substrates with nutrients for the larvae. Preferably, the system is connected to a stream of nutrients (1) that contains the different types of nutrients that the larvae need, and a stream of water (2), which helps to obtain the necessary plasticity for the drive of the resulting substrate in form of mud.

The two streams enter the mixer (3), where a series of blades that are inserted in an axis remove and mix the different components and nutrients that the larvae need. The turn can be one way, or include several sets of blades with opposite turns. The mixer (3) will be in the form of a hopper, conical, pyramidal or truncated cone or any shape that allows the mixing taking advantage of the existing space. Once the food has been mixed, it is transported outside, for example by means of an endless screw, whose first end is inside the mixer (3). The mixed feed stream (4) leaves the mixer (3) until it reaches a second worm or extruder (5) with one or two spindles. At the outlet of the extruder (5), the sludge stream (6) is driven to a narrowing (7), in which the sludge can be directed towards a flexible or fixed line to be introduced into the reactor (8). The additional stream (9) would correspond to an extra stream of water or neonatal insects that can be introduced into the reactor (8) along with the sludge, through the narrowing (7).

The reactor (8) may have a cylindrical, hexagonal, square or rectangular profile, due to its ease of modular scaling, or any other, generally having its inscribed diameter less than or equal to its length.

Figure 2 describes the solids extraction system inside the reactor (8) where insect larvae are grown. Inside the reactor (8) are the larvae, remains of undigested food substrate and substrate biodegraded by larval and microbial activity. The system is composed of an inlet air stream (10), which enters into an air delivery system (1 1), such as a compressor, from where it is propelled into the reactor (8) by means of the corresponding driving. The elements that are to be evacuated are carried by the current of air that has entered the reactor (8) from the bottom, and they exit through the outlet pipe (12), larger in diameter than the inlet, to the solid-gas separator (13). The air delivery system (1 1) will therefore be strong enough to drag the solids from the reactor (8).

In the solid-gas separator (13) (cyclone, filter or expansion chamber, for example) it is possible to separate the solids from inside the reactor (8) into two streams, one of gas free of solids and another stream of solids (14 ) which contains all the solid elements inside the reactor (8). The solid stream (14) feeds a solid-solid separation system (15) (screening, flotation, aeration, centrifugation, etc.), which allows the larvae to be separated into a stream of larvae (16) and the rest of solids in the waste stream (17). The solids extraction system can also function as a reactor aeration system (8), simply by driving less inlet air stream (10) in the air discharge system (1 1), so that it is capable of removing the stale air without removing larvae and nutrients.

Figure 3 describes a first embodiment of the digestion reactor (8). This reactor (8) preferably comprises a system composed of a rectangular housing (81) into which both the food and the larvae are introduced and their cultivation is carried out. The aeration system contains a diffuser (83), in this case corresponding to a diffuser plate in which there are perforations (84) where the air exits to the internal digestion chamber of the reactor (8). The gas stream enters through a rectangular aeration duct (82), in the lower part of the reactor (8), and exits through the perforations (84) of the diffuser plate, passing through the bed formed by the larvae and the food allowing substrate oxygenation and larval aerobic metabolic activity. The perforations (84) may not be too large to prevent material from falling into the aeration duct (82).

Figure 4 describes a second embodiment of the digestion reactor (8), in which the housing (81) is cylindrical. The aeration system contains the diffuser (83), in this case a cylindrical diffuser conduit, in which the perforations (84) are located, where the air inside the digestion chamber leaves. The air enters through a circular aeration duct (82 '), at the bottom of the reactor (8), and exits through the perforations (84) of the diffuser line, passing the air through the bed formed by the larvae and the food.

Figure 5 describes the general scheme of a third embodiment of the reactor (8) whose housing (81) is also cylindrical. The aeration system of this embodiment comprises a blind aeration duct (82 "), that is to say no outlet at its innermost end to the reactor (8), which blows a gaseous stream into the interior of the reactor (8). Aeration (82 ") has a diffuser (83) formed by a face of its outer wall. In the diffuser (83) the perforations (84) will be arranged so that the air can escape.

The reactor (8) may be hermetically sealed and connected to an oxygen pressure vessel that maintains a hyperbaric oxygen pressure, which spreads homogeneously in the diet or medium from which the larvae are fed. necessarily through the perforations (84) as will be explained below. Alternatively, it may have a non-hermetic cover (85) at at least one of the ends to facilitate aeration and sampling or control of the reactor contents.

Figure 6 describes the general operation of the reactor (8) in hyperbaric conditions of air or oxygen, preferably with a pressure between 1 and 6 bar and can reach 20 bar, depending on the type of larva. The reactor (8), is connected to a hyperbaric pressure system formed by a pressure line (18) plugged into a pressure vessel or delivery equipment (19), which injects the gas into the reactor (8). In the pressure line (18) there is a control or shut-off valve (20), which allows the gas inlet to the reactor (8) to be controlled. Likewise, a pressure control system formed by a meter (21) acting on an exhaust valve (22) or purge the reactor (8) is introduced if the detected pressure exceeds a predefined value. The pressure gas inlet into the reactor (8) can be through the aeration duct itself (82, 82 ', 82 ") or by an added inlet, preferably also at the bottom of the reactor (8) and covered by the Nutrients and larvae.

The gas stream should allow adequate humidity, temperature and oxygen diffusion for the correct survival and development of the larvae, the optimum conditions being known in the state of the art.

Claims

1- Insect larvae breeding equipment comprising a larval digestion reactor (8) and a feeding system, said equipment being characterized in that it comprises an aeration system and a solids extraction system, wherein said system of Solids extraction comprises an air delivery system (11) configured to introduce an inlet air stream (10) into the bottom of the reactor (8), and an air outlet duct (12).

2- Equipment according to claim 1, wherein the solids extraction system further comprises a solid-gas separator (13) connected to the outlet line (12).

3- Equipment according to claim 2, wherein the solid extraction system further comprises a solid-solid separator (15) that separates the larvae from the solid waste materials.

4- Equipment according to any of the preceding claims, wherein the aeration system comprises an aeration duct (82, 82 ', 82 ") located at the bottom of the reactor (8), connected to the digestion chamber by means of a diffuser (83) with a plurality of perforations (84) along the digestion chamber.

5- Equipment according to claim 4, wherein the aeration duct (82, 82, 82 ") comprises an inlet for the inlet air stream (10) generated by the solids extraction system.

6- Equipment according to any of the preceding claims, wherein the aeration system is the solids extraction system with the air delivery system (1 1).

7- Equipment according to any of the preceding claims, wherein the feed system comprises a mixer (3) of water and nutrients and an extruder (5) with a narrowing (7) prior to the reactor (8).

8- Equipment according to the preceding claim, wherein the mixer (3) has a hopper shape. 9. Equipment according to any of claims 7-8, comprising an endless screw whose first end is inside the mixer (3) and a second endless screw or extruder (5) of one or two spindles.

10- Equipment according to the preceding claim, where the extruder outlet (5) reaches the narrowing (7) and where said narrowing (7) is connected to a conduit, flexible or fixed, to be introduced into the reactor (8).

1 1- Equipment according to any of claims 7-10, comprising in the narrowing (7) an inlet for an additional stream (9) of water or neonatal insects.

12. Equipment according to any of the preceding claims, further comprising a hyperbaric air or oxygen pressure system inside the reactor (8) which is airtight.

13. Equipment according to the preceding claim, wherein the pressure is between 1 and 6 bar, or is equal to or less than 20 bar.

14. Equipment according to any of claims 12-13, wherein the hyperbaric pressure system is formed by a pressure line (18) connected to a pressure vessel or delivery equipment (19) and to the reactor (8), and a internal pressure gauge (21) to the reactor (8) connected to an exhaust valve (22) or reactor purge (8).

15. Equipment according to the preceding claim, wherein the pressure line (18) comprises an inlet to the reactor (8) through the aeration system.

16. Equipment according to any of the preceding claims, wherein the reactor (8) has a cylindrical, hexagonal, square or rectangular profile.

17. Equipment according to any of the preceding claims, wherein the reactor (8) is sealed.

18. Equipment according to any of the preceding claims, wherein the inscribed diameter of the reactor (8) is equal to or less than its length. 19- Solid extraction system, for the insect breeding equipment of claim 1, characterized in that it comprises an air delivery system (11) configured to introduce an inlet air stream (10) in the lower part of the reactor (8), and an outlet duct (12) of air.

20- A system according to claim 19, comprising a solid-gas separator (13) after the exit line (12).

21- System according to claim 20, further comprising a solid-solid separator (15) for separating the larvae from solid waste materials.

22- Feeding system for the insect breeding equipment of claim 1, characterized in that it comprises an inlet of a stream of water (2) and a stream of nutrients (1) in a mixer (3), and an extruder (5) connected to the reactor (8) through a narrowing (7).

23- System according to claim 22, comprising an inlet for an additional stream (9) of water or neonatal insects in the narrowing (7).