WO2016079348A1

WO2016079348A1 - Structural module for the support of helophytes

Info

Publication number: WO2016079348A1
Application number: PCT/ES2015/000167
Authority: WO
Inventors: Federico Guillermo Witt Sousa; Carlos CÁMARA MARTINEZ
Original assignee: Blue Water Solutions, S.L.
Priority date: 2014-11-20
Filing date: 2015-11-20
Publication date: 2016-05-26
Also published as: ES2530762B1; ES2530762A1

Abstract

The invention relates to a structural module for the support of helophytes, a water treatment facility comprising same, and a water treatment method. The structural module for the support of helophytes comprises a frame (1) including apertures (3) and open receptacles (4) secured vertically in the apertures (3). The receptacle (4) and the frame (1) are preferably connected at two points in order to prevent rocking and overturning. The lower end of the receptacle (4) is equipped with at least one through-hole (8) for the passage of the roots of the helophyte (7), allowing a mesh of roots to form in the frame (1). The invention also relates to a water treatment facility comprising the structural module, a method for assembling said module and a water treatment method.

Description

STRUCTURAL HELOPHITE SUPPORT MODULE

D E S C R I P C I Ó N

OBJECT OF THE INVENTION

The present invention is part of the technical field of facilities and methods of water purification and regeneration of purified water for reuse.

More specifically, a helophyte support structural module, a water treatment installation comprising at least one module as described, a method of mounting the helophyte support structural module and a water treatment method using at least one are described of said structural modules.

BACKGROUND OF THE INVENTION Purification is a solution currently used to solve the environmental problem resulting from the discharge of wastewater. For this, the water that has already been used for a certain function and that no longer presents adequate conditions so that it can be returned to the natural channel is subjected to one or several treatments that allow it to recover sufficient quality parameters for its discharge or If an additional water regeneration treatment is carried out behind the purification, they can be reused.

One of the known systems of the state of the art for water treatment is phytodepuration. In most cases, palm plants or floating aquatic plants are used (such as water hyacinth, water lilies, water lentils, etc.). Within this type of treatment systems, the most prominent are currently those that use amphibious macrophytes that grow in their natural state rooted in the bottom substrate of shallow lagoons (helophytes or helophyte plants, also known as amphibious or emerging plants) or in soils saturated with water on the edge of these lagoons (hygrofite plants). The most used macrophyte species they belong to the genera Typha (bulrush or enea), Phragmites (carrizo), Sparganium (espargaño), and Juncus or Scirpus (reeds).

The most relevant characteristic of this type of plants that allows them to be used in treatment systems is that their stems and roots have a practically hollow parenchymal tissue, called an aeromechyme, which facilitates the internal transfer to the roots of the oxygen produced in the leaves. The driving force of said aerenchymal transport is the gradient of partial pressures of O ₂ that is established between the submerged roots, consumers of this gas, and the photosynthetic tissues that release it after the photochemical reaction of charge separation that leads to the dissociation of The water molecule.

Roots and rhizomes are organs of the plant that obtain their metabolic energy exclusively through the process of cellular respiration so they use oxygen that reaches them from the upper green structures. However, a part of this oxygen also escapes the rhizosphere, the microcosm that surrounds the roots, where symbiotic bacteria oxidize the organic matter dissolved in the water.

In addition, under certain conditions, nitrification-denitrification and anammox processes can also occur, which contribute to the removal of nitrogen from water. Therefore, the ecosystem formed by the root network and the microorganisms associated with it in the rhizosphere is the true purifying agent of phytodepuration systems. Depending on the relative position of the plants with respect to water, phytodepuration systems can be classified into four groups:

1) Group of artificial surface flow wetland systems (HAFS). These systems mimic the natural growth of emerging macrophytes, but in waterproofed artificial wetlands. Plants are grown rooted in the bottom substrate, and their stems and leaves emerge on the surface of the water. The main limitation of this method is that, since the roots are buried in the flooded bed, the transfer of oxygen to the rhizosphere is useless, taking advantage of the aerenchymal pathway as there is no contact between the roots and the water to be treated. Therefore, the efficiency of clearance is poor and limited to that carried out by microorganisms epiphytes that grow on the submerged part of the stem taking advantage of the oxygen emitted by these green tissues and the passive exchange of gases that cross the atmosphere-water interface. 2) Artificial subsurface flow wetlands (HAFSs). The artificial wetlands waterproofed in this case are filled with an inert material of coarse granule, usually gravel or sand, in which macrophytes are planted. The water, which should not come to the surface of the bed, drains through the interstices of the bed and during its journey is forced to meet the roots. These systems provide a good contact between the water to be purified and the root network of the plants, but the transfer of oxygen is limited to that produced through the airfield, without allowing the direct gaseous exchange between the atmosphere and the water or the 0¿ contribution of green stems to water. Depending on the direction of drainage through the substrate there are vertical or horizontal systems. These two modalities are often used sequentially if nitrogen is intended to be removed. The main drawback of this type of systems is that the interstices through which the water must circulate fill up with some speed, forming preferential paths or forcing the liquid medium to surface on the granular bed, a fact that damages the purification efficiency of the crop and that greatly limits its useful life.

3) Floating treatment wetlands (FTW), emerging macrophyte filters forced to grow in flotation (FMF) and Schwimmkampen or artificial floating islands. This set of systems involves the development of helophyte cultures that form floating tapestries of roots and rhizomes. The helófitos are planted by means of different devices with floats in the surface of channels or rafts waterproofed. As they grow and proliferate vegetatively, a root and rhizomatic lattice forms sufficiently locked so that the plants increase their size by staying upright and floating autonomously on the surface of the wetland. Each crop behaves as a single floating mass because the density of locked plants is less than that of water. Numerous more or less effective planting methods and units have been described to develop these types of treatments.

All are based on planting elements that confer buoyancy to young seedlings while trying to counteract their tendency to dump while distributing them. regularly until the root network is formed, which can cover the wetland or form independent islands (floating islands). While artificial floating islands have focused almost exclusively on wetland restoration and water remediation in natural areas, the FTW and FMF have also been used to treat wastewater. Its main advantage with respect to subsurface flow wetlands is that the risk of clogging of the spaces through which water must circulate is eliminated and the formation of preferential roads is reduced.

However, in advanced stages of the crop the floating fabric becomes so thick that an insurmountable bathtub for gases is established, so that the main limitation of this set of floating systems is that, when the root tapestry covers the entire surface of the bucket of the wetland or channel, the transfer of oxygen between the atmosphere and the rhizosphere is carried out exclusively by the pathway of the airfield. For this reason, FTW systems are usually interspersed with plant-free zones that allow water aeration, which decreases the yield per unit area. On the other hand, due to the rocking and swings of the young plants, the establishment of a tapestry root sufficiently dense to achieve a purifying efficiency requires months or even periods of the order of one year. In addition, depending on the depth of the channel or raft, in these systems water can circulate freely below the tapestry without penetrating the rhizosphere, which also reduces the performance of the scrubber filter.

4) Semi-submerged helophyte filters. These filters try to compensate for the buoyancy of the helophytes to ensure that the root and rhizomatic framework is floating between two waters a little below the surface. The depth to which said root and rhizomatic framework is located depends on the amount of ballast placed under the plants at the time of planting. The advantages associated with these purification systems are the same advantages of the FTW and FMF filters (there is no risk of clogging or formation of preferential paths) without their main drawback (the barrier formed in the atmosphere / water interface due to the dense floating root mantle that gets to accumulate on the surface). In theory, with these systems, in addition to the air-oxygen transfer to the rhizosphere, free diffusion and direct gas exchange between the atmosphere and the water to be treated are allowed. However, known planting units of the state of the art have failed to obtain satisfactory results. Within the purification systems with semi-submerged helophyte filter during installation and during the first stages of crop development, the root framework has not yet been formed and the seedlings must be distributed in an orderly manner. In addition, young plants must be helped to stand upright and counteract the action of the wind and the tendency to overturn due to the growth and elevation of the center of gravity of their aerial parts. In later stages, the semi-submerged position of the crops involves additional technical problems. Various patents are known from the state of the art which describe the type of systems. For example, in the ES2324277 patent, the plantation is carried out in containers at the bottom of the raft or canal, with very little water. Once the root tapestry is established, a process that can last up to a year, the water sheet is raised to the final height . The set formed by plants, root tapestry and built-in planting elements rises, but the ballast, calculated so that it is strictly necessary to counteract the buoyancy of the set, keeps the semi-submerged raphees, floating between two waters a few centimeters below the surface. As specified in the patent, the ballast consists of some granular material, such as coarse sand or gravel, mixed with the soil substrate in the plant containers. Other patents related to the use of lower ballasts are also known to keep the pins upright without tipping over.

As described in patent ES2331566, the plantation is carried out on a flexible floating net or net arranged on the surface of the water, and the ballast, housed as a counterweight in sacks or bags made of plastic net under the plant containers, It is placed at that time. The counterweight acts by moving the center of gravity of the planting unit further down to help prevent the natural tendency to turn plants when they grow. Complex formulas have also been developed for the calculation of ballasts to be added to the devices. These formulas allow to relate different parameters associated to the system such as the volumetric density of the ballast itself, the weight of the rhizosphere and its volumetric density, the volumetric density of the stems and the weight of the part of these that should be submerged, as well as the weight corresponding to the part of them that is intended to remain out of the water. The values of the parameters listed must be known or established experimentally; However, this calculation seems unrealizable in practice since the weight and volumetric density of the aerial part of the plants vary with the time of day and the different weather and weather conditions depend, and many other factors have to be taken into account (age of the plant, vegetative state in different seasons, health, pruning or mowing, epiphytic fauna, retained bubbles and air pockets formed, etc.). In addition, the submerged parts of the plants grow incessantly and. Although all parameters and factors involved in the formula could be known well in advance (of the order of months and years), in order to always maintain the desired depth, the ballast should be modified continuously, day by day. This is absolutely impossible because to implement the systems known in the state of the art the ballast is incorporated at the time of planting. Therefore, to modify the amount of ballast in advanced stages of the crop, it would be necessary, respectively, to remove the rootballs, an equally impracticable task since the roots and rhizomes of the adjoining plants by then have interwoven, or introduce other bags or sacks through the root pencil to hang them under the containers. The direct consequence of not being able to modify the amount of ballast once the root network is formed is that, if at the time of planting a suitable ballast is applied for the advanced phases of the crop, it will be too sunk in its initial phase and the plants they will die drowned, and if instead they choose to apply a suitable ballast for the time of planting, the crop will tend to float as it develops, emerging completely and becoming a floating filter type FTW or FMF.

Thus the known systems of the state of the art suffer from several problems. Surface flow systems with emerging macrophytes only favor the transfer by direct diffusion and the contribution of submerged green tissues; and subsurface flow systems and FMF filters only use the pathway of the airfield. The roots of the surface flow systems, buried in the soil substrate, barely come into contact with the water they must purify. The growth of the root and rhizomatic framework outside any substrate or bed eliminates any possibility of clogging, saturation, undue overflow or formation of preferential paths, problems of which subsurface flow systems suffer in the medium term. DESCRIPTION OF THE INVENTION

The present invention describes a helophite support structural module that is intended to be submerged in water, motionless and fixed at a certain depth. The helophytes planted in the structural module can be emerging or amphibious (helophytes) or other plant varieties that may be suitable for the treatment of sewage in canals, rafts, lagoons and any waterproofed area. Preferably, the helophyte support structural module is portable and can be installed in combination with more identical modules or with other types of elements to form a water treatment installation that is also part of the object of the invention. Also object of the present invention is a water treatment method of a purification channel or raft by the use of at least one helophite support structural module as described. A preferred method of assembly of said helophyte support structural module is also described. The structural macrophyte support module of the present invention comprises a rigid frame that is fixed by means of fasteners that immobilize it to the desired height. The crop is in said frame, so when giving the height of the frame placement, the height of the crop is also regulated, allowing absolute control of the depth at which the scrubber tapestry is placed (composed of the reticular lattice of the helophytes) in All phases of the crop. In addition, the fact that the structural planting module is fixed allows the cultivation to be independent of any climatic or meteorological event or circumstance, as well as the life cycle itself or the growth of the plants. The key to the present invention is to facilitate planting and ensure the correct growth and vegetative propagation of the macrophytes responsible for the water treatment process. In addition, the structural planting module is placed in a fixed position allowing easy and precise depth regulation for the development of the root and rhizomatic framework of the macrophytes so that atmospheric oxygen is transferred without barriers or resistance to diffusion through the interface air / water Another advantage derived from the use of the module, the installation and the method described in the present invention is that an additional oxygen supply to the water is favored, coming from the submerged green parts of the macrophyte stems. In a preferred embodiment, the water treatment installation comprises at least one helophyte support structural module and at least one module inside which other aquatic macrophytes are found. More preferably these aquatic macrophytes are filamentous macroalgae. The helophytes found in the structural support modules are selected from the list comprising Typha spp., Phragmtes spp., Sparganium spp., Iris spp., Juncus spp. or Scirpus spp., or any combination thereof. More preferably they are selected from the list comprising Typha domingensis, Typha latifolia, Saccharum offícinarum, or any combination thereof.

In each installation the number of modules needed is placed according to the needs of the client or the population for which the water is purified. Thus, they can be designed and sized differently for each specific case, providing great versatility.

Filtering by helophytes provides a solvent secondary treatment in water purification processes as it allows to eliminate organic matter and greatly reduce suspended solids. It also allows to reduce mineral nutrients whose presence leads to water eutrophication.

The roots of the helophytes establish a framework and remain well secured and submerged in the proposed structural module that provides them with a three-dimensional support that is placed and maintained at a fixed height within a purification channel or reservoir. At the same time, thinner adventitious roots hang from the rigid network of thick roots that facilitate the contact of the water with the purifying bacteria of the helophytes.

The structural support module comprises a frame and a plurality of containers fixedly and rigidly attached thereto. In these containers is where the helophite rootballs are housed. The fact that the connection between the containers and the frame is rigid is what allows that the helofitas lodged in the containers do not suffer movements of reciprocating nor can overturn, that were the most important problems derived from the use of the systems of the state of the art. The structural support module acts as a firm scaffolding for the formation of a root framework when plants grow.

When this fabric has been formed, it is perfectly interwoven in the frame and the whole frame and the fabric acts allowing the rooting of young plants so that they propagate vegetatively and colonize the free spaces. These new plants grow already immobilized and without being subjected to rocking or swinging movements that would prevent an establishment of the crop in the form of grass or compact hedge.

In addition, the structural support module of the present invention is placed in a fixed position at a certain height where it remains fixed. The height at which it is fixed means that the module does not suppose a barrier that prevents the optimal exchange of gases between the atmosphere and the water to be treated and, on the other hand, it is adequate so that a loose tangle of fine roots hangs from the module. to reach the bottom of the channel or purification tank in which the structural support module is installed. The reticular lattice growth can be done directly in the purification channel or raft in which the structural support module is to be installed or it can be carried out in another water tank and then transferred to the installation site. This allows to accelerate the process of starting a WWTP in which you want to install and allows you to quickly replace sections of facilities that are already underway and that for any reason are in poor condition.

As previously described the treatment facility comprising at least one structure module! of support can additionally include other modules, among which the use of a module with filamentous macroalgae is worth mentioning. The function of this module is to reduce the concentrations of eutrophizing nutrients below the limits established by the corresponding environmental regulations, especially for cases of sensitive areas with risk of eutrophication.

The module comprising macroalgae allows the cultivation of filamentous macroalgae to act as a tertiary water treatment that has already passed through the module Structural support of helophytes. As the macroalgae assimilate nitrogen and phosphorus nutrients for growth and proliferation, these contaminants are removed from the water. Also the filamentous macroalgae act as a support for symbiotic bacteria that contribute to purification.

With respect to the preexisting filodepuration systems, the present invention allows the three ways of transferring oxygen to water to be used for the oxidation of organic matter. These routes are the direct diffusion, the aerénquima and the photosynthetic contribution to the epiphytic bacteria from the submerged green part of the plant. This is achieved because the raphees and the basal part of the helophyte stem are submerged.

In comparison with flexible meshes or networks, the rigid frame structure of the present invention serves as scaffolding and structural support for the installation and fixation of the containers with the seedlings; support and fixing element functions so that the crop is kept submerged to the proper depth; and functions of the immobilizer element of the seedlings, preventing their balancing, swaying and any turning, torsion or tipping action that could damage the vegetative propagation and colonization through rhizomes. Likewise, the structural module acts as a framework for the root network to act as an elevated substrate so that the new shoots have a firm point of support and anchorage instead of being loose, as is the case when flexible meshes or networks are used. From the structural module hangs a lax framework of adventitious roots forming a curtain covered with purifying bacteria to the bottom of the canal or raft.

With the proposed helophyte support structural module, the contact between the water and the rhizosphere is optimal when the root system is submerged in the water. Another advantage of the present invention is that the slightly submerged position of the scrubber root framework lowers the relative position of the scrubber root framework, reducing the amount of water that circulates freely through the bottom of the canal, raft or artificial wetland, so Increases its performance with respect to filters of floating aquatic macrophytes or emerging floating macrophytes (FMF).

On the other hand, compared to submerged helophyte filters that support the semi-submerged floating position of the root and rhizomatic tapestry in a calculated ballast of beforehand by means of a complex formula whose parameters are difficult to determine, the present invention keeps the crop fixed and sunk to the desired height and depth by means of simple anchoring or clamping devices. In addition to incorporating each plant the module comprises a plurality of containers that are preferably alveoli of forest or agricultural use, preferably of grid, which are simple and standard production devices.

On the other hand, in contrast to the known ballast placement methods of the prior art, the installation system object of the present invention does not imply the need for individual receptacles for a ballast as a counterweight under or inside each plant container ; in this case the fixation acts on the complete installation unit, in fact on the rigid support itself or frame. As described above, the semi-submerged macrophyte systems described to date do not allow the amount of ballast to be altered once the root framework is formed. As a consequence, if at the time of planting a suitable ballast is applied for the advanced stages of the crop, it will be too sunk in its initial phase and the plants will drown; on the contrary, if it is decided to apply a ballast more suitable for the initial phases of the crop, the set will tend to float as it develops, emerging completely and becoming a floating filter (FTW or FMF). In comparison, the present invention facilitates any intervention on the setting of height and depth at any time or phase of cultivation, independent of the system from any circumstantial eventuality and also from the life cycle itself and the growth of the plants.

In addition, the mechanism by which the overturning of the seedlings is prevented in the present invention consists in the firm fixing and anchoring of the containers to a rigid frame. This procedure avoids that, for example by a gust of air, the aerial parts of the plants tip over and remain locked in a horizontal position, lying permanently on the water despite the presence of the counterweight.

Additionally, the structural module described herein prevents the plant from being subjected to rocking and swinging movements. It has been found that this type of movement, common in systems with floating or semi-submerged plants through the use of a lower counterweight, they damage and delay the establishment of the root network and the propagation of new plants, and the colonization of the free spaces of the crop. Finally, it should be noted that the systems and installations described in the state of the art that use emerging macrophytes or helophytes imply very long terms of up to one year, to develop the scrubber tapestry and therefore to begin to fulfill the mission for which they have been implanted However, with the present invention a firm anchoring substrate is provided for young roots and new plants, consisting of the support framework and root framework, which accelerates the formation of a tight lawn. This allows the term required until the purification facilities are fully functional and operational to be reduced to a few months.

The essential advantages provided by the proposed invention are that the plants do not turn over and by having a support for the roots and rhizomes, new plants (those that are born from the rhizomes) can stand up and also grow without overturning, which allows their once they effectively colonicize the empty spaces between seedling and seedling, which is the goal of planting and which is not achieved with any system known in the state of the art. This is essential because if the plants are subject to fluctuations, rocking, etc. They do not grow or proliferate. Thus, the fact that the structural support module described completely prevents the tilting of the containers and is rigid and fixed in a certain position has contributed to obtaining the described advantages.

DESCRIPTION OF THE DRAWINGS

To complement the description that is being made and in order to help a better understanding of the characteristics of the invention, according to a preferred example of practical implementation thereof, a set of drawings is attached as an integral part of said description. where, for illustrative and non-limiting purposes, the following has been represented:

Figure 1.- Shows a perspective view of a helofite support structural module formed by double mesh and in which the helophite root ball containers are appreciated. Figure 2.- Shows a profile view of the helophyte support structural module of Figure 1.

Figure 3a.- Shows a view of a helophite support structural module in which helixite rootballs are observed in the containers.

Figure 3b.- Shows a view of a helophite support structural module in which the root framework has already been formed. Figure 4.- Shows a view of a structural module of helophyte support that is attached to a wall of the water tank by means of bars with angled ends that rest on the walls of the channel or purification tank.

Figure 5.- It shows a view of a structural module of helophyte support that is attached to a wall of the water tank by means of cables comprising tensioners to regulate the position of the module with respect to the walls of the channel or purification tank.

Figure 6 - Shows a view of a structural module of helophyte support that is attached to a wall of the water tank by means of bars that are fixed by means of screws to the walls of the channel or purification tank.

Figure 7.- Shows a perspective view of the connection between the first body and the outer tube and the second body and the inner tube.

Figure 8.- Shows a view of the structural module shown in Figure 7 in which the separation between the first body and the second body determined by the height of the outer tube is appreciated PREFERRED EMBODIMENT OF THE INVENTION

Examples of embodiments of the present invention are described below with the aid of Figures 1 to 8. A structural module of helophyte support is proposed, an installation of treatment comprising at least one structural module of helophyte support. a method of assembling the structural module of helophyte support and a method of water treatment of a channel or purification tank. The helophyte support structural module comprises a frame (1) with a plurality of openings (3), and a plurality of open containers (4) and each rigidly fixed vertically in an opening (3) of the frame ( one ). In said containers (4) is where helophytes are grown. An example of a helophite support structural module is shown in Figure 1. Said helophite support structural module can be totally or partially submerged in a body of water at a fixed depth. In another embodiment, the structural support module is not submerged in water.

An essential feature of the module of the present invention is that the attachment of the containers (4) to the frame (1) is rigid to allow the correct growth of the helophytes and the formation of the reticular framework without overturning or balancing said helophytes.

Likewise, the structural helophyte support module (2) is fixed at a certain depth of the water body in which it is placed to ensure that the roots of the plant are always submerged in the water and that the upper part is in the air (out of! water).

The containers (4) can be tubes, sockets, etc. In each of them a helophyte is grown. Said containers (4) comprise a mouth (5), intended for the passage of the aerial part of the helophyte (7), and at least one passage opening (6) intended for the passage of the roots of the helophyte (7). The passage openings (6) are vertical grooves extending from the mouth (5) of the container (4) to an opposite end. Alternatively, said containers (4) comprise two mouths, one upper and one lower (5), the upper one intended for the passage of the aerial part of the helophyte (7), and the lower one for the passage of the roots of the helophyte, being able to count with a passage opening (6) also intended for the passage of the roots of the helophyte (7). Preferably the dimensions of the containers may be the standard for the Alveoli for commercial use agricultural use and its upper mouth adjusts to the opening (3) of the frame (1). The inside of the container (4) can be filled with peat or other plant substrate and the young helophytes whose roots and rhizomes can emerge when they grow through the lower mouth and / or through the grooves ( 6) to establish the root framework.

Preferably the passage openings (6) of the containers (4) are longitudinal grid openings. In this case the containers have longitudinal grid walls, with open grooves through which the roots and rhizomes can leave for the colonization and propagation of the crop to form a well-rounded continuous root framework. In fact, vegetative propagation by means of rhizomes is the means of reproduction of helophytes during the months of growth, with the dissemination of seeds relegated to dispersion over a long distance. In figures 3a and 3b the evolution of the root network has been represented from a first image in which the helophite rootballs are observed and a second image in which the root fabric that is formed is observed.

In an exemplary embodiment such as that shown in Figure 2, the frame (1) comprises at least one additional support point (8) arranged at a distance (d) from the openings (3) so that the container (4) is join the frame (1) at least in the opening (3) and at the additional support point (8). Preferably the frame (1) is rigid.

For example, if the frame (1) is a flat body, the container (4) can be fixed by its mouth (5) to the opening (3) and to ensure that the joint between the container (4) and the frame ( 1) be a rigid joint the container (4) can be attached to the frame (1) in the mouth (3) and also at the additional support point (8). Preferably, the connection of the mouth (5) to the opening (3) is carried out by means of joining devices.

In this case the mouth (5) of the container (4) is attached to the opening (3) of the frame (1) in which it is located and a base of the container (4), opposite the mouth (5), is joined to the additional support point (8) by means of a lateral support configured to prevent the oscillation of the containers (4). Preventing the oscillation of the containers (4) prevents the occurrence of overturns, headings or swings of the container (4) with the helophytes that could cause said helophytes to grow correctly or that could even cause their broth so that the roots remain exposed to the air causing Even the death of the plant.

In an exemplary embodiment, the frame (1) comprises at least one flat reinforcement formed by rods that cross and delimit an infinity of grids that conform the openings (3). In other embodiments, the frame (1) may comprise three, four, five, six, etc. flat armor In other examples the framework is made up of. at least, flat armor with circular openings or with different geometric shapes, which allow the fixation of the socket, ensuring its rigidity and in sufficient number to allow new seedlings to emerge through them.

In another embodiment, the frame (1) comprises a first body (10) and a second body (11), both with openings (3) arranged one above the other and separated from each other a distance (d) less than or equal to the length of the containers (4) that are fixed to the frame (1) in said openings (3) of the first body (10) and fitted in the openings (3) of the second body (11). The separation distance (d) must be such that it allows the attachment of the container (4) to the first body (10) and the second body (11) to ensure a rigid fixation at two points and that the container (4) does not move . More specifically, the containers (4) are connected to the openings (3) of the first body (10) and fitted into the openings (3) of the second body (11). The framework could also comprise three, four, five, six, etc. flat bodies The embodiment in which there are multiple bodies allows, for example, to improve the holding of the containers (4) if they are placed between several bodies.

In the openings (3) of the second body (11) the containers (4) can be fitted or introduced with little clearance so that there are no forces on the container (4).

Additionally said second body (11) may comprise the additional supports (8) in case the module has them. Otherwise, the container (4) can be attached to the second body (11) directly in the openings (3) of said second body.

In the case that the frame (1) comprises the first body (10) and the second body (11), these can be flat reinforcements formed by rods that cross and delimit an infinity of conforming grids of the openings (3) and they are separated from each other by columns (13) that join them. As can be seen in Figures 7 and 8, in an exemplary embodiment the columns (13) that join the first body (10) and the second body (11) are formed by internal tubes (18) arranged vertically and linked to the second body (1 1) and outer tubes (19) arranged around the inner tubes (18). In this arrangement, one end of the outer tube (19) abuts the second body (11) and another end of the outer tube (19) abuts the first body (10).

Furthermore, the outer tube (19) can have a length coinciding with the separation distance (d) between the first body (10) and the second body (1 1).

Preferably the inner tubes (18) are longer than the separation distance (d) and the outer tubes (19) are interchangeable. In order to vary the distance between both bodies, additional outer tubes (19) can be placed, on which they are already placed, thus increasing the distance between bodies, or replace the outer tubes (19) with others that have a greater or lesser height according to the needs. The fact that the inner tubes (18) are of a greater height allows the first body (10) to move away from the second body (11). In this embodiment, the inner tubes (18) are arranged in openings (3) of the second body (11) and are linked to said second body (11) by means of tomilleria (20). In addition, the outer tubes (19) have measures greater than the measurements of the openings (3) of the first body (10) and the second body (11) in order to act as a stop and rest on said second body (11) and serve as a support to the first body (10) without sneaking through the openings (3).

To ensure that the helophyte support structural module maintains a fixed position at the desired depth in the body of water, the frame (1) can comprise bars (12) that are attached to the frame (1) and have ends angled configured to rest on the walls (16) of a purification channel or raft. These are lateral fasteners in the installation unit, by way of

inverted as seen in figure 4 or support element that rests on the edges of the channel or purification pool. The lateral fasteners can be supported directly, being fixed by the own weight of the support module, or can be anchored to the edges by means of screws or screws.

In another embodiment, the helophyte support structural module comprises a plurality of mechanical joining elements (14) intended to join the walls (16) of the purification channel or reservoir. Preferably, the mechanical joining elements (14) are screws or screws, as can be seen, for example, in figure 5. In this case, the mechanical joining elements (14) can additionally comprise tensioners (15) which allow the depth to be adjusted and equalized. of the suspension points of the support module when it is suspended or hung from the outside of the purification channel or tank by means of braces.

Another embodiment, shown in Figure 6, the helophyte support structural module comprises the use of metal frames fixed directly to the frame (1), which in turn screw the walls (16) of the purification channel or tank using screws. The fixing place of the brackets on the walls determines the height at which the installation unit is fixed. You can also use strips with height-adjustable insertion points or other similar fixing means. Figure 6 shows buoys that are elements that prevent the frame from warping or sinking through the center when placed in a raft instead of in a canal. The use of buoys for this function is not part of the object of protection of this patent. In another embodiment, the structural support module (2) is suspended in the water body by means of braces. In an exemplary embodiment, it can be hung by means of steel braided cables from eyebolts anchored at the edges of the purification channel or raft or from posts anchored next to the walls (16). In this embodiment the length of the cables can be regulated by the use of tensioners and prisoners.

In case the structural support module (2) is placed in rafts of great width, the module may additionally comprise at least one float or buoy (17) attached to the frame (1). The use of a float or buoy prevents the frame (1) of the module (2) from combating and sinking excessively in the areas furthest from the edge of the the raft

It is also an object of the invention a water treatment installation in which there is at least one helophite support structural module (2) as described above. Preferably, the helophytes in the containers (4) of the structural support module (2) of the treatment plant are selected from the list comprising Typha spp., Phragmites spp. Sparganium spp., Iris spp., Juncus spp. or Scirpus spp., or any combination thereof. More preferably said helophytes are selected from the list comprising Typha domingensis, Typha latífolia, Saccharum officinanim, or any combination thereof.

Additionally, the water treatment facility comprises other aquatic macrophyte plants that can be aquatic vascular plants. The installation can also include additional modules inside which macroalgae are housed.

In a preferred embodiment of the water treatment installation, the helophyte support structural module is arranged in a channel crossed by the water to be treated which comprises a plurality of vertical partitions intended to compartmentalize or divide said channel avoiding short circuits, shortcuts or preferential roads.

More preferably the vertical partitions are placed in the channel substantially perpendicular to the walls of the channel, have a length less than the width of the channel and are placed alternately and opposite along its length.

Also object of the present invention is a method of assembling a helophite support structural module as described above.

In the embodiments in which the structural module comprises the frame (1) with a first body (10) and a second body (11) separated by columns (13) formed by an inner tube (18) and an outer tube (19 ) The mounting method comprises the steps of:

iv) remove the first body (10), v) placing additional outer tubes on the outer tubes (19) so as to increase the separation distance between the first body (10) and the second body (11),

vi) place the first body (10).

Likewise, the assembly method may additionally comprise the steps of:

iv) remove the first body (10) and remove the outer tubes (19),

v) placing outer tubes (19) of different lengths than the outer tubes (19) removed in the previous stage,

vi) place the first body (10).

These stages allow varying the separation distance between the frame bodies (1). Another example of modifying said separation can be carried out by carrying out the following steps:

iv) remove the first body (10).

v) placing additional outer tubes on the outer tubes (19) so as to increase the separation distance between the first body (10) and the second body (11),

vi) place the first body (10).

This makes it possible to increase the thickness of the frame (1) (that is, to increase the separation distance (d) between the first body (10) and the second body (11)) depending on, for example, the containers (4) used when begin planting the rootballs of the plants and the type of radical system of these plants. You can start for example with a size and after a certain time, such as a year, when a reticular lattice has already formed that covers the separation distance between the first body (10) and the second body (11) then You can increase this distance (d).

As previously described this can be done by adding new outer tubes (19) over existing ones or by removing existing ones and placing ones of greater height. In this way the surface that the roots have to grow is increased and with this the treatment potential is increased without having to perform pruning. That is, the present invention allows the temporary variation of the separation distance (d) between the two bodies (10, 11) of the frame so as not to have to perform pruning and optimizing the root surface.

Finally, a method of water treatment of a purification channel or raft comprising the following steps is considered part of the invention:

a) fix a helofert support structural module (2) in a water tank filled with water up to an operational height as described in one of claims 1 to 14 at a height that allows the structural support module to be fully submerged in water,

b) let the roots of the helophytes grow out of the containers (4) through the passage opening (6) until they form a locked reticular lattice.

In another embodiment, the structural support module is placed in a water tank different from the purification channel or reservoir. In said water tank, the roots are grown to form the necessary framework to allow the correct support of the plants and subsequently transferred to the purification channel or reservoir. After that, it is introduced into the purification channel or tank already filled to the operating height and fixed in the desired position.

In addition, the treatment method may comprise an additional step of passing the water to be treated through an additional module inside the macroalgae that receives the water from the purification channel or reservoir in which the structural support module is placed of helophytes (2).

An example is described below in which they use structural support modules for the water treatment necessary for a rural urban nucleus for which an equivalent population of 150 inhabitants has been calculated. In an exemplary embodiment, two purification channels are constructed in parallel, each 50 m long and with a rectangular section 2.5 m wide and 1 m deep. These channels are waterproofed with 1 mm thick linear low density polyethylene geomembrane. The objective is to establish in each channel a dense network of intertwined roots and rhizomes of helophytes and well locked that form a rhizosphere of appropriate characteristics, dimensions and purification capacity so that, after adequate pretreatment, reduce the parameter of the DB05 of the urban wastewater of the town. In a preferred embodiment, the variety of helophyte that is grown is of the species Typha domingensis. On the ground, next to each channel, 20 structural modules of helophyte support are mounted, each with a 2.5 m long and 2.5 m wide frame. In this example, the frame is made up of two 3.5 mm thick steel welded wire mesh cut to size. The mesh weave used is 5 cm square. Both meshes are placed in parallel, 10 cm apart and joined by welding of iron bars. To give greater rigidity to the set, cross-corrugated iron bars are welded. The set forms a rigid three-dimensional frame 2.5 m long, 2.5 m wide and 10 cm thick. In addition to being stainless steel, the frame could be made of aluminum, preferably anonymous aluminum.

The frame (1) could be made of metal body covered with plastic. In another embodiment, the frame (1) could be made of polyethylene. polypropylene or a similar material.

The containers for the plants are of grid of agricultural and forestry use. The containers used in this case are frustoconical, of high density polyethylene, and its dimensions are: 5 cm internal diameter at the top, 4 cm diameter at the base and 16 cm in length. In one embodiment, the containers could be made of polypropylene, PVC or other similar material. The mouth has a reinforcement that allows its fixation by means of forest clips to the support mesh. Inside, stuffed with peat, the helophytes are housed, one for each container. The connection between the container (4) and the frame (1) can also be made by wires, flanges or other means. In another embodiment, the containers (4) could be made of ceramic material. In another embodiment, the frame can also be made of ceramic material. The containers are inserted into the support structure at regular intervals, crossing both rigid reticles, and firmly fixed or anchored to the upper reticle by means of forest staples. The distribution is 20 containers per square meter. The rootballs of the plants are then introduced into the containers. Therefore, a planting density of 20 feet of plant per square meter is established. The introduction of the plants in the containers can also be carried out prior to fixing them in the frame of the support structure.

In this exemplary embodiment, the structural support modules comprise inverted L-shaped iron bars and electro-welded to the installation unit. These elements have the appropriate dimensions so that once the horizontal segment rests on the walls (16) of the channel, the upper rigid mesh of the installation unit (first body (10)), in which are the containers (14 ) is located 30 cm below the edge of the walls (16) of the canal.

The structural support modules are placed contiguously inside the purification channels, which have previously been filled with water up to 80 cm, based on the installation systems that are incorporated. Thus, in the present example the roots of the plants remain between 10 cm and 26 cm below the surface of the water, therefore the basal parts of the stems being submerged 10 cm, which will provide additional oxygen to the bacteria that grow on them. . In addition, there will be no physical barriers that offer resistance to the free diffusion of gases through the inferred air / water.

A thick network of roots and rhizomes has formed a few months after planting in the frame of the module, and new plants that propagate from the rhizomes are well anchored and do not lie down or drown as they grow. From that moment, the WWTP is fully operational and works at full capacity, achieving 95% removal of BOD5 and sufficient removal of suspended solids, as well as a reduction of the Nt and Pt parameters.

An example of application of the described treatment method would be its use for regeneration of purified water in order to use it as irrigation water.

Claims

one. ; Structural module of helophyte support characterized by comprising:

- a frame (1) comprising a plurality of openings (3), and

- a plurality of open containers (4) and each of them is fixed vertically in an opening (3) of the frame (1) and these containers (4) comprise:

-a mouth (5), intended for the passage of the aerial part of the helophyll (7), and

-at least one passage opening (6) intended for the passage of the roots of the helophyte (7).

2. - Helophite support structural module according to claim 1 characterized in that the passage opening (6) of the containers (4) are vertical grooves extending from the mouth (5) of the container (4) to an opposite end .

3. - Helophite support structural module according to claim 1 characterized in that the frame (1) comprises at least one additional support point (8) disposed at a distance (d) from the openings (3).

4. - Helophite support structural module according to claim 3 characterized in that the mouth (5) of the container (4) is connected to the opening (3) of the frame (1) in which it is located and a base of the container ( 4), opposite the mouth (5), is attached to the additional support point (8) by means of a lateral clamp configured to prevent the oscillation of the containers (4).

5. - Helofite support structural module according to one of claims 1 to 4, characterized in that the frame (1) comprises at least one flat reinforcement formed by rods that cross and delimit an infinity of grids forming the openings (3) .

6. - Helophite support structural module according to one of claims 1 to 5 characterized in that the frame (1) comprises a first body (10) and a second body (11) both with openings (3) arranged one above the other and separated from each other a distance (d) less than or equal to the length of the containers (4) that are fixed to the frame (1) in the openings (3) of the first body (10) and fitted in the openings (3) of the second body (11).

7 - Helophite support structural module according to claims 3 and 6 characterized in that the additional support point (8) is in the second body (11).

8. - Helofite support structural module according to claim 6, characterized in that the first body (10) and the second body (11) are flat reinforcements formed by rods that cross and delimit an infinity of grid conforming openings (3 ) and are separated from each other by columns (13) that link them.

9. - Helophite support structural module according to claim 1 characterized in that the frame (1) is rigid.

10. - Helofite support structural module according to claim 1 characterized in that the connection between the containers (4) and the frame (1) is carried out by means of joining devices (9).

11 - Helofite support structural module according to claim 8 characterized in that the columns (13) are formed by internal tubes (18) arranged vertically and linked to the second body (11) and external tubes (19) arranged around the inner tubes (18) so that one end of the outer tube (19) abuts the second body (11) and another end of the outer tube (19) abuts the first body (10).

12. - Helophyte support structural module according to claim 11 characterized in that the outer tube (19) has a length coinciding with the separation distance (d) between the first body (10) and the second body (11).

13 - Helophyte support structural module according to claim 11 characterized in that the inner tubes (18) are arranged in openings (3) of the second body

(11) and are linked to said second body (11) by screws (20).

14 - Helophite support structural module according to claim 11 characterized in that the outer tubes (19) have measures greater than the measurements of the openings (3) of the first body (10) and the second body (11).

15. - Helofart support structural module according to claim 11, characterized in that the inner tubes (18) are longer than the separation distance (d) and the outer tubes (19) are interchangeable.

16. - Helofite support structural module according to one of claims 1 to 15, characterized in that the frame (1) additionally comprises bars (12) that are attached to the frame (1) and have angled ends configured for lean on the walls (16) of a purification channel or raft.

17. - Helophite support structural module according to claim 16 characterized in that the bars (12) have an inverted "L" shape.

18. - Helofite support structural module according to one of claims 1 to 1? characterized in that it comprises a plurality of mechanical joining elements (14) intended to join the walls (16) of a purification channel or raft.

19. - Helofite support structural module according to claim 18 characterized in that the mechanical joining elements (14) additionally comprise tensioners (15) attached to the frame (1).

20. - Water treatment installation characterized in that it comprises at least one helophite support structural module (2) as described in one of claims 1 to 19.

21. Water treatment installation according to claim 20 characterized in that the helophytes arranged in the containers (4) of the structural support module (2) are selected from the list comprising Typha spp., Phragmites spp., Sparganium spp. , Iris spp .. Juncus spp. or Scirpus spp., or any combination thereof

22 - Water treatment installation according to claim 21 characterized in that the helophytes are selected from the list comprising Typha domingensis, Typha latifolia, Saccharum offícinarum. or any of its combinations.

23.- Water treatment installation according to one of claims 20 to 22 characterized in that in addition to helophyte plants comprise other aquatic macrophytes.

24. - Water treatment installation according to claim 23 characterized in that the aquatic macrophytes are aquatic vascular plants.

25. - Water treatment installation according to one of claims 20 to 24, characterized in that it additionally comprises a module inside which macroalgae are housed.

26. - Water treatment installation according to one of claims 20 to 24, characterized in that the helophite support structural module is arranged in a channel, crossed by the water to be treated, comprising a plurality of vertical partitions intended to compartmentalize said channel avoiding short circuits, shortcuts or preferential water paths.

27. - Water treatment installation according to claim 26 characterized in that the vertical partitions are placed in the channel substantially perpendicular to the walls of the channel, have a length less than the width of the channel and are placed alternately and opposite to along its length.

28. - Method of assembly of a helofite support structural module as described in one of claims 11 to 19 characterized in that it comprises the following steps:

i) place the inner tubes (18) in corresponding openings (3) of the second body (11) so that they are linked.

ii) place the outer tubes (19) around the inner tubes (18) with one end in contact with the second body (11),

iii) place the first body (10) so that the inner tubes (18) are inserted into corresponding openings (3) of the first body (10) and that said first body (10) is in contact with the free end of the outer tube (19).

29. - Assembly method according to claim 28 characterized in that it additionally comprises the steps of:

iv) remove the first body (10) and remove the outer tubes (19), v) placing outer tubes (19) of different lengths than the outer tubes (19) removed in the previous stage,

vi) place the first body (10).

30. - Assembly method according to claim 28 characterized in that it additionally comprises the steps of:

iv) remove the first body (10),

v) placing additional outer tubes on the outer tubes (19) so as to increase the separation distance between the first body (10) and the second body (11).

vi) place the first body (10).

31. - Method of water treatment in a purification channel or raft characterized by comprising one of the following stages:

a) fix a structural module of helophyte support (2) in a water tank filled with water up to an operational height, as described in one of claims 1 to 19 at a height that allows the helophyte support module to remain totally submerged in water.

b) let the roots of the helophytes grow out of the vessels (4) through the passage opening (6) until they form a locked reticular lattice.

32. - Water treatment method according to claim 31, characterized in that steps a) and b) are carried out in a water tank different from the purification channel or raft and subsequently introduced into the purification channel or reservoir already filled until operational height and stage c) is performed.

33. - Water treatment method according to one of claims 31 to 32. characterized in that it also comprises an additional step of passing the water to be treated by an additional module inside which macroalgae that receives the water from the water are housed. purification channel or raft in which the helophyte support structural module (2) is placed.