WO2011080578A1

WO2011080578A1 - Organic filter planted with european and/or tropical desertic canes for the treatment of polluted water, soil or air

Info

Publication number: WO2011080578A1
Application number: PCT/IB2010/003363
Authority: WO
Inventors: Thierry Jacquet
Original assignee: Phytorestore
Priority date: 2009-12-31
Filing date: 2010-12-29
Publication date: 2011-07-07
Also published as: BRPI1000098B1; BRPI1000098A2; CN102712513B; FR2954762A1; CN102712513A; FR2954762B1

Abstract

The invention relates to a planted organic filter for the treatment of pollutants, said planted organic filter comprising an inlet for the pollutants to be treated, an outlet for the non-degraded pollutants, and means of filtration and depollution arranged between the inlet and the outlet of the pollutants. The invention is characterised in that a) said filtration and depollution means take the form of an organic substrate consisting of between 10 and 20% of aggregates that are preferably non-soluble and have an irregular surface, more than 30% of plant fibres in the form of a ligneous material, and between 20 and 40% of compost containing more than 30% of ligneous material and preferably having a biological stability index (BSI) higher than 0.5, and b) said organic substrate is planted with european and/or tropical/desertic canes, said canes preferably encouraging a high carbon dioxide sequestration. The invention also relates to a device for treating polluted water, soil or air, comprising at least one above-mentioned planted organic filter, and to a method for treating polluted water, soil or air, including the introduction of polluted water, soil or air into an above-mentioned device.

Description

Organic filter planted with European and / or tropical / desert rods for treatment

polluted water, soil or air

The present application claims the priority of the patent application FR 0906430 filed on December 31, 2009 in the name of the same holder and the contents of which are incorporated by reference in the present application.

Field of the invention

The present invention relates to an organic filter planted with European and / or tropical / desert rods for the treatment of polluted water, soil or air and a depollution process using such a planted organic filter.

Previous Art

Now aware of the public health risks posed by pollution, French and European standards for the discharge of pollutants, whether for gaseous, liquid or solid matrices, are becoming increasingly restrictive. .

Among the pollution problems, those integrating the carbon dioxide emission are now particularly echoed, especially with the determination of the carbon footprint associated with an activity.

The current solutions to these problems of depollution are however hardly satisfactory, especially if one takes into account the stakes of sequestration of the carbon dioxide in order to limit the global warming.

Thus, when one is interested in the treatment of sludge, the sanitation solutions used today rely, for the most part, on depollution processes by biological purification in sewage treatment plants for wastewater and wastewater. spreading on cultivated soils for agricultural effluents. Due to the disadvantages of these techniques (foul odors, difficult aesthetic integration in the landscape, unsuitable solution for the treatment of small amounts of pollutants, high energy consumption, high operating costs), other solutions have been developed. Among the techniques developed, we find filtration techniques on alluvial beds planted or not.

The sand bed filtration recommended for stand-alone sanitation is an ancient technique described in standard XP P16-603 August 1998 (reference DTU 64 .1). This simple and effective technique relies on infiltration-percolation of wastewater into a large sandbank. However, this technique requires on the one hand large surfaces and poses, on the other hand, clogging problems involving a regular renewal of the filter sand.

To overcome these disadvantages of the sand bed filter, the planted beds have been developed. These beds are alluvial filters consisting of gravel, sand, or crushed layers, planted with plants benefiting from an important root system to maintain permeability within the massif, usually reeds or bamboos.

In addition and to avoid the risk of clogging, these planted masses are built by two or three and operate alternately, so as to enjoy a regular rest period. With a structure comprising three filters, the rest time is then at most two times the operating time.

The latest solutions developed in terms of depollution are based on bio-sanitation, or phytoremediation, and is based on the ability of some plants to take certain pollutants from the soil to accumulate or, for some plants, degrade. However, the resistance of plants to toxic materials varies greatly from one species to another, and on the other hand, the elimination of polluted plants, due to an accumulation of pollutants, is problematic.

In order to further improve the depollution, the inventor has previously developed a pollution control process based on "phytolixiviation", or leaching by plants, described in PCT International Application WO 2006/030164.

This process is based on an alternation of aerobic / anaerobic period allowing the degradation of organic pollutants by the microorganisms of the rhizosphere of a planted organic filter and the Remobilization (by dissolution) of non-degradable species, especially metal species, to allow their leaching (phytolixiviation) and their passage to a second compartment acting as a concentration filter.

In view of the current problems of depollution, there is however a recurrent need for new solutions to obtain a more effective and / or less expensive depollution.

Summary of the invention

The inventor has now developed a new process of depollution, which process is both simple and economical, which is based on a specially developed organic plant filter, which planted organic filter is used in the context of the depollution process as described in PCT International Application WO 2006/030164 incorporated herein by reference.

The subject of the present invention is thus a planted organic filter for the treatment of pollutants, which planted organic filter comprises:

- an entry for the pollutants to be treated,

- an output for non-degraded pollutants,

filtration and depollution means interposed between the inlet and the outlet of the pollutants, characterized in that the said filtration and depollution means take the form of:

a) an organic substrate composed of 10-20% aggregates, which aggregates are preferably insoluble and with an irregular surface, more than 30% of plant fibers in the form of a woody material, and 20- 40% of compost containing more than 30% of ligneous material preferably having a biological stability index (BSI) greater than 0.5,

b) which organic substrate is planted with European and / or tropical / desert canes, which cannes preferably favor a strong sequestration of carbon dioxide. The organic substrate then allows a carbon dioxide scavenging rate greater than 10% of the inflow, preferably between 10 and 35%.

The organic planted filter according to the invention is thus designed to operate according to the positive modified carbon balance resulting from the flux calculations modeled by FRANCEZ and VASANDER (1995) for two peat bogs Sphagnum fallax and Carex Rostrata.

For the filter according to the invention, and considering an incoming flow of wastewater or urban sludge of 1 kg / m ² / day of COD and DB05 and dry matter (DM), it is possible to estimate that the carbon is mainly accumulated within the filter (60%.) in the form of mineralized sludge, that a lesser part (30%) is released into the atmosphere in the form of carbon dioxide and methane by decomposition, and finally that low share (10%) is used for the crop production of the filter according to the invention. It is therefore possible to conclude that the organic filters planted according to the invention have an extremely positive carbon balance and this especially as these filters require almost no energy to operate. This is a real break with traditional treatment plants (biological, chemical, physical or even membranes) which are, globally, large emitters of carbon in the atmosphere, much more important elsewhere than the livestock which is however often mentioned.

Advantageously, said insoluble aggregates having an irregular surface are chosen from pozzolan, flint and siliceous sands.

Preferably, these plant fibers in the form of a woody material are selected from the group comprising sugarcane bagasse, coconut bark, palm leaves, bark, especially pine bark. , and all biomass from European and / or tropical / desert cane.

Advantageously, a high lignin content makes it possible to fix the pollutants by changing the chemical form of these, and thus avoids a risk of saturation of the filter or release of pollutants. Lignin makes it possible to obtain a significant index of biological stability (ISB) of the organic substrate. The Biological Stability Index (BSI) is the effective ability of an organic product to produce stable humus in the soil. This coefficient can be determined simply by the methodology described by LINERES A BJAKOVICH (Characterization of the biological stability of organic inputs by biochemical analysis, pp. 159-168) In bECROUX A I6NAZI (ed.) Organic matter and agriculture. of the earth analysis (Gemas) Fifth forum of the reasoned fertilization (Comifer) 16-18 November 1993). this methodology concerns, on the one hand, the measurement of the crude cellulose content, composed mainly of celluloses and a small proportion of lignins and hemicelluloses (method NF V03-040), and on the other hand on the fractionation of VAN SOEST & WINE (1967, 1968), which differentiates four compartments known to be equivalent to soluble molecules, hemicelluloses, celluloses and lignins and cutins. By comparing the biochemical composition of different products and the carbon mineralization measured by respirometry, LINERES & bJAKOVITCH have established this index of biological stability (ISB) whose calculation method is included in the standard NF XP U 44-162.

By European or tropical / desert rods, preference is given to:

1) All perennial grasses with stems that are harder than 1 meter and whose annual biomass growth exceeds 3 tonnes per hectare, which allows for high carbon sequestration as they generally belong to the so-called C4 plant classes .

2) plants with a strong development of underground roots because all these plants have a rhizome and support immersion in water ranging between 10 cm and 1 meter depending on the species (which is not the case for bamboos that can not not withstand strong hydraulic variations).

3) plants whose rhizomes are also characterized by their ability to adapt to variations in the levels of organic filters, which makes it possible to load filters up to a maximum thickness of 1.5 meters of organic substrate, if necessary.

4) other plants that produce, after drying, stubble rich in woody matter (more than 90% of the dry matter after composting) and low in moisture (10 to 15% depending on the species, while short-rotation Willow Spindles) have humidity levels greater than 20 or 30). All these rods therefore have a high valuation potential for their biomass as energy because of their PCI (calorific value) higher than wood (with a PCI between 4000 and 5000) and because of their characteristic of their non putrescible stubble (which makes them often use as building materials for thatched roofs for example).

5) Finally, pants with a high power of evapotranspiration, which always exceeds 4mm per day and per m ² .

Advantageously, the said European and / or tropical / desert canes are chosen from the group comprising Acorus Calamus, Amnophila arenaria, Ampelodesmos mauritanicus, Andropogon gerardii, Arundo donax sensu, Bromus inermis, Calamagrostis acutiflora, Calamagrostis arundinacea, Carex morrowii, Carex hanged , Chasmanthium latifolium, Chionochloa conspicua, Chusquea culeou, Colocasia esculenta, Cortaderia fulvida, Cortaderia richard /, Cortaderia selloana, Cymbopogon citratus, Cyperus ensiatus, Cyperus giganteus, Cyperus longus, Cyperus papyrus, Cephalopsia cespitosa, Elegia capensis, Equisetum aericanum, Equisetu hyemale , Equisetum fluviatile, Equisetum maximum, Fargesia murielae, Fargesia nitida, Glyceria maxima, Hibanobambusa tranquillans, Indocalamus solidus, Indocalamus tessellatus, Juncus acutus, Juncus effusus, Leymus arenarius, Miscanthus sinensis and var., Miscanthus floridulus, Miscanthus sacchariflorus, Miscanthus giganteus, Molinia altissima, Molinia arundinac a, Molinia caerulea, Panicum virgatum, Panicum rigidulum, Papyrus papyrus, Pennisetum and var., Phalaris arundinacea, Saccharum arundinaceum, Saccharum officinarum, Saccharum ravennae, Schoenoplectus californicus, Schoenoplectus tabernaemontanis, Scirpus lacustris, Sorghum halepeus, Spartina alterniflora, Sponiopogon sibiricus, Stipa Stipa sp / endens, Typha minima, Thysanolaena latifolia, Zizania aquatica, Zizania latifolia and Zizania palustris, Greslania rivularis, Greslania multiflora, Flagellaria sp., Scirpus subulatus, Sacharum spontaneum, Andropogan leucostachyus, Colocasi gigantea, Typhonodorum lindlleyanum, Cyperus distans, Heliconia latisphana, Heliconia stricta and Medicago sativa.

Preferably, the organic filter planted according to the invention comprises at least two species, preferably three species and particularly preferably at least four different species of European cane and / or tropical / desert. The inventor has been able to demonstrate that the organic filter planted according to the invention makes it possible to avoid the formation of bad odors, which are sometimes problematic for certain pollutions. This good efficiency is in particular the fact of an excellent permeability (greater than 15 mm / h) of the organic substrate, which results for a part of the humification rate higher than 50% and makes it possible to limit the clogging phenomena but especially of optimize the oxygenation of microorganisms of the rhizosphere involved in the degradation of pollutants. It is also this rhizosphere in contact with organic matter rich in humus that will allow the formation of a root system able to act on the form of pollutants.

In the context of an implementation of the organic filter planted according to the invention in the pollution control process described in PCT International Application WO 2006/030164, no addition step of natural organic acids is furthermore necessary to to clean up heavy metals. The implementation of said planted organic filter thus greatly simplifies this process but also to reduce the cost of use. In addition, no step of adding disinfectants (lime and / or chlorine) is also necessary for good disinfection of urban sludge.

Finally, the inventor has been able to demonstrate the effectiveness of the filtered organic filter according to the invention on a very large number of pollutants in the context of the treatment of pollutants in solid, liquid or gaseous form; which efficiency is illustrated in the examples.

These elements make it possible to avoid the addition of natural organic acids and disinfectants (lime and chlorine).

The present invention also relates to a treatment device for the treatment of polluted water, soil or air comprising at least one organic filter planted as described above.

Finally, the subject of the present invention is a method of treating polluted water, soil or air comprising the introduction of polluted water, soil or air into such a device. Preferably, this treatment process is intended for trapping carbon dioxide with a carbon dioxide scavenging rate greater than 10% of the influx, preferably between 10 and 35%.

More preferably, and when the organic filter comprises brown peat as compost, said treatment process is intended for the trapping of heavy metals with an abatement rate greater than 90% of the incoming flows, which heavy metals are chosen from particularly preferred manner among copper, lead, zinc and aluminum. Description of the figures

Table 1 describes the details of the characteristics of the European canes of the invention.

Table 2 describes the detail of the characteristics of the tropical / desert rods of the invention.

FIG. 1 is a schematic sectional view of a device for the treatment of wastewater with two successive organic filters with vertical and horizontal filtration respectively, a settling basin and a trapping filter.

Figure 2 is a schematic sectional view of a planted organic filter for the treatment of wastewater.

Figure 3 is a schematic sectional view of a second organic filter planted for the treatment of wastewater.

Figure 4 is a sectional view of a device for the treatment of polluted sludge with a first planted organic filter followed by a trapping filter.

Figure 5 is a schematic sectional view of a horizontal organic filter for the treatment of polluted air.

Figure 6 is a schematic sectional view of a vertical organic filter for the treatment of polluted air.

Detailed description of the invention

The organic filter planted according to the invention will be vertical or horizontal filtration as it aims to treat effluents flowing vertically or horizontally. For the organic filter planted according to the invention, the European or tropical / desert rods are chosen from plants not benefiting from accumulating capacities known for pollutants. Thus, after a clean-up cycle, these plants are easily valued, particularly in the field of energy, furniture, construction, ornament, and even in the field of food human or animal. For the latter case, it should be noted that many canes are used as fodder for cattle in many developing countries.

It is also possible to use other bank plants or wetlands with the same lack of accumulator capacity for pollutants.

These different plants also have a reduced winter rest period compared to reeds. Thus, the effectiveness of depollution is increased compared in particular to reed filters because of an increased tolerance with regard to temperature variations.

By way of example of European and / or tropical / desert canes, mention may be made of the plants chosen from the group comprising Acorus Calamus, Amnophila arenaria, A pelodes os mauritanicus, Andropogon gerardii, Arundo donax sensu, Bromus inermis, Calamagrostis acutiflora, Calamagrostis arxininacea, Carex morrowii, Carex pendula, Chasmanthium latifolium, Chionochloa conspicua, Chusquea culeou, Colocasia esculenta, Cortaderia fulvida, Cortaderia richardi, Cortaderia selloana, Cymbopogon citratus, Cyperus ensiatus, Cyperus giganteus, Cyperus longus, Cyperus papyrus, Chaseschampsia cespitosa, Elegia capensis, Equisetum americanum, Equisetum hyemae, Equisetum fluviatile, Equisetum maximum, Fargesia murielae, Fargesia nitida, Glyceria maxima, Hibanobambusa tranquillans, Indocalamus solidus, Indocalamus tessellatus, Juncus acutus, Juncus effusus, Leymus arenarius, Miscanthus sinensis and var., Miscanthus floridulus, Miscanthus sacchariflorus, Miscanthus giganteus, Molinia altissima, Molin ia arundinacea, Molinia caerulea, Panicum virgatum, Panicum rigidulum, Papyrus papyrus, Pennisetum and var., Phalaris arundinacea, Saccharum arundinaceum, Saccharum officinarum, Saccharum ravennae, Schoenoplectus californicus, Schoenoplectus tabernaemontanis, Scirpus lacustris, Sorghu halepeus, Spartina alterniflora, Sponiopogon sibiricus, Stipa calamagrostis, Stipa splendens, Typha minima, Thysanolaena latifolia, Zizania aquatica, Zizania latifolia and Zizania palustris, blackberries / ania rivularis, Greslania multiflora, Flagellaria sp., Scirpus subulatus, Sacharum spontaneum, Andropogan leucostachyus, Colocasi gigantea, Typhonodorum lindileyanum, Cyperus distans, Heliconia latisphana, Heliconia stricta and Medicago sativa.

The details of the characteristics of these European and tropical / desert rods are described in Tables I and II respectively.

Advantageously, the European and / or desert / tropical rods of the invention are amphibian plants, with high floodability and a large drought period, and having a very large root network, to allow the development of the rhizosphere in depth, on more than 1,5m and width, over 5m.

Preferably, the organic filter planted according to the invention comprises at least two species, preferably three species and particularly preferably at least four different species of European cane or tropical / desert.

According to a specific embodiment in which the organic filter is intended to treat polluted water, the various species of European and / or tropical / desert canes of the planted organic filter of the invention are chosen from the group consisting of Bromus inermis, Cyperus Longus, Molinia caerulea, Molinia arundinacea, Stipa splendens, Saccharum ravennae, Schoenoplectus tabernaemontanis, Scirpus lacustris, Cortaderia fulvida, Cortaderia richardi, Cortaderia selloana, Cyperus papyrus, Papyrus papyrus, Cyperus giganteus, Miscanthus sinensis, Miscanthus floridulus, Miscanthus sacchariflorus, Miscanthus giganteus, Molinia altissima, Cyperus ensiatus, Elegia capensis, Saccharum arundinaceum, Saccharum officinarum, Schoenoplectus californicus, Zizania aquatica, Zizania latifolia, and Zizania palustris.

According to another specific embodiment in which the organic filter is intended to treat polluted air, the various species of European and / or tropical / desert canes of the planted organic filter of the invention are chosen from the group consisting of Carex orrowii, Carex pendula, Equisetum hyemale, Equisetu fluviatile, Equisetum maximum, Stipa calamagrostis, Stipa splendens, Calamagrostis acutiflora, Cortaderia fulvida, Cortaderia richardi, Cortaderia selloana, Equisetum americanum and Calamagrostis arundinacea.

According to yet another specific embodiment in which the organic filter is intended to treat polluted soils, the various species of European and / or tropical / desert canes of the planted organic filter of the invention are chosen from the group consisting of Carex morrowii , Carex pendula, Mol / nia caerulea, Molinia arundinacea, Panicum virgatum, Panicum rigidulum, Miscanthus sinensis, Miscanthus floridulus, Miscanthus sacchariflorus, Miscanthus giganteus, Molinia altissima, and Panicum amarum.

The density of European and / or tropical / desert rods in the planted organic filter is advantageously between 5 and 15 plants / m ² , preferably this density is 10 plants / m ² on average.

To ensure a good efficiency of the planted organic filter, the thickness of the organic substrate is between 300 and 1500 cm depending on the pollution to be performed.

More specifically, the thickness of the organic substrate is between 300 and 700 mm in the case of an organic filter for the depollution of water or polluted soils and between 300 and 1500 mm in the case of an organic filter to to the depollution of polluted air.

For the organic substrate, compost will be understood, preferably a compost as defined by the NF U44-051 standard, but also preferably having at least one of the characteristics listed in Table III which follows.

Table III

* See work by GUIDON and VALAT (1988) concerning the study of Baupte peat in the Channel for the definition of these different components.

Preferably, said compost will be rich in lignin and fibers, with a lignin content of greater than 30%, such as that observed in particular in blonde peat. The nature of the blonde peat is well known to those skilled in the art and results from the processing of Sphagnum and is rich in cellulose fiber and carbon. Its texture is called fibric and its other essential characteristics are its low density, its high water content and its low content of mineral ash because often young (2000 years). An equivalent material can be obtained with a composting time of 1 to 3 years minimum, preferably 2 to 3 years minimum.

The output for non-degraded pollutants advantageously takes the form of one or more recovery drains, which are well known to those skilled in the art. To facilitate the evacuation of leachate, the pollutant outlet is positioned in a draining layer consisting of pebbles, gravel or other equivalent draining material, organic substrate.

For a good efficiency of the draining layer, its thickness is chosen between 100 and 1500 mm, preferably between 150 and 1000 mm and, particularly preferably, between 200 and 500 mm.

The organic filter according to the invention is isolated from the ground by means of sealing means, which prevent the infiltration of pollutants into the natural environment and are well known to those skilled in the art. Preferably, said sealing means will take the form of a geomembrane. In the case of diffuse soil pollution, the filter is made without a geomembrane with a simple addition to the existing soil of an organic substrate comprising a compost rich in fibrous material greater than 30.

The organic filter according to the invention comprises an aeration system, which advantageously connects the draining layer to the surface. This aeration system makes it possible to improve the efficiency of the periods of dewatering in the framework of the organization of the successions of irrigation / drying cycles described in PCT international application WO 2006/030164.

This aeration system can take the form of vents connected to the base of the organic filter planted by means of ducts or ducts. Said aeration system may in particular be connected to the recovery drains arranged in the draining layer.

Advantageously, this aeration system takes the form of vents connected on the one hand to the organic substrate and, on the other hand, to the recovery drains arranged in the draining layer at the base of the planted organic filter and this by means of ducts. or pipes.

Depending on the nature of the "effluent" to be treated, the nature of the organic filter planted according to the invention may differ slightly. Thus, in the context of a treatment of gaseous effluents, the organic filter planted according to the invention will also comprise an irrigation system.

Preferably, the organic filter planted according to the invention will comprise one or more valve (s) associated with the exit of non-degraded pollutants and at the inlet for pollutants to be treated, and possibly to the irrigation system in the case of a gaseous effluent treatment.

These various valves make it possible to improve the supply and the drainage of the organic filter planted according to the invention and, above all, to organize the succession of irrigation / drying cycles (anaerobic / aerobic period) of the process as described in the international application PCT WO 2006/030164 to optimize the degradation of pollutants by microorganisms of the rhizosphere.

Advantageously, these valves make it possible to organize irrigation / drying cycles of the organic filter planted as a function of the pollution to be treated.

Advantageously, these valves make it possible to organize a distribution of the irrigation / drying periods corresponding to a ratio of 2/1 to 1/50, preferably of 1/1 to 1/20, for example of 1/2 to 1/20, and particularly preferably from 1/3 to 1/20.

According to a particular embodiment, the organic planted filter according to the invention aims at trapping pollutants, especially metallic, and the compost used then takes the form of prereminated vegetable debris having the characteristics listed in Table IV which follows.

Table IV

Proportion component

Organic matter> 50%

Siccité> 30%

PT Between 5 and 10%

Potassium Between 5 and 10%

Calcium Between 5 and 10%

Magnesium Between 5 and 10%

fiber rate> 40%

Density between 0.2 and 0.4

Organic ash content <6%

Carbon / Nitrogen ratio> 30 Such characteristics can be obtained simply with a minimum composting time of 3 years of plant debris or with brown peat.

Indeed, the inventor has been able to demonstrate the effectiveness shown in particular brown peat for fixing heavy metals. This peat comes from the transformation of woody plant debris (various trees) and Ericaceae. It is composed of fibers mixed with finer elements, resulting from further degradation of the plants, giving it a mesic texture. She is older (5000 years old) than blonde peat.

With this particular form of planted organic filter, the inventor was able to demonstrate that the metal elements were attached to the peat particles at the peat / root interface. More specifically, it has been demonstrated that in less than 10 minutes, 90% of zinc (at an initial concentration of 1 mmol / l) was adsorbed to brown peat. The time of water infiltration to the drains is sufficient to fix the zinc on the peat. It is thus possible to recover and then valorize certain pollutants as raw material. Research conducted on copper-polluted (Cu ² +) soil showed the presence of copper metal (Cu) in the form of aggregates and this while the leachates did not contain it. It therefore seems that the biological activity of the microorganisms present at the root level and / or that of the roots themselves allows the reduction of the organic copper in metallic form and the consequent aggregation of the copper atoms in the form of grains; which reduction and aggregation are similar to detoxification.

This particular form of organic filter planted in any case allows to obtain an extreme concentration of pollutants cheaply and the organic part of the filter, which concentrates the pollutants, can then be simply evacuated to a suitable treatment center (burial, incineration or to allow, in case of abundant deposits, the establishment of extractive industry).

A second object of the invention is a device for the treatment of polluted water, soil or air containing at least one organic filter planted according to the invention as described above. The pollution in question may result from at least one pollutant chosen from the group comprising heavy metals, organochlorines, salts, sulfur, sulphites and their mixtures.

In a first embodiment, the device aims at the treatment of polluted water, which device comprises two stages, called vertical filters and horizontal filters and each composed of at least one organic filter planted according to the invention with vertical or horizontal filtration respectively .

Preferably, the number of independent planted filters for each stage (composed respectively of organic filters planted with vertical or horizontal filtration) is increased to 4 or more, preferably to about 10. This number makes it possible to increase the rest period by compared to the operating time and improve the efficiency of treatment all without adding chemical reagents.

The device may also comprise, downstream of a possible liquefaction compartment, means for separating the suspended solids present in the polluted water or sludge. These means will advantageously take the form of a degril them, a pit all waters and / or a decanter-digester.

Typically, the irrigation / drying cycles of the planted organic filter will be from 4 hours to several months in the case of polluted sludge, preferably 12 hours to 2 months and particularly preferably of the order of one month.

The organization of these cycles will be slightly different in the case of wastewater treatment, with irrigation / drying cycles from 4 hours to several months, preferably from 1 to 15 days and particularly preferably from the order of from 1 to 7 days.

This important variation is due to the fact that in the case of sludge pollution (as in the case of soils), the dissolution of non-degradable species requires a significant washing time, whereas in the case of water pollution, non-degradable species already found in a more easily soluble form simplifying their leaching in the planted organic filter. In another embodiment, the device is for the treatment of gaseous effluents, which device comprises at least one planted organic filter having a thickness of at least 30 cm; this thickness constituting a threshold for the vertical filtering walls or for the filtering roofs.

Said device can then take the form of an organic filter planted with horizontal filtration or a "vertical filter wall".

The device then comprises at least one entry for gaseous effluents which is positioned in the organic substrate and further comprises an irrigation system allows reasoned irrigation and that the substrate is cyclically under hydromorphic conditions.

The gaseous effluents to be treated are then forced through the planted filter and part of the pollutants is then degraded by the microorganisms. Another part is transformed into a poorly soluble and non-bioavailable form. The rest of the pollutants are retained in the filter and then lixivé, the leachates are then recovered in the drain at the bottom of the filter.

In this case, the irrigation / drying cycles of the planted organic filter will be from 2 hours to 24 hours, preferably from 5 to 200 minutes and particularly preferably from the order of 10 minutes.

The fact that the irrigation / drying cycles are so short compared to the wastewater is related to the effluent to be treated itself. Indeed, the introduction of air greatly accelerates the rate of drying of the planted organic filter which implies de facto a significant reduction in the time of the irrigation / drying cycles so as to have a planted organic filter viable and functional.

In yet another complementary embodiment, the device is for the treatment of polluted soils.

In this case, the device is similar to that used for the treatment of polluted sludge and it can also include a first liquefaction compartment to transform polluted soils or "polluted sludge" by increasing the dryness so as to facilitate the treatment of these soils. As before, the device may then comprise, downstream of this liquefaction compartment, means to separate the suspended matter present in the polluted sludge as described above.

Otherwise, it is also possible to replace the first liquefaction compartment by a planted organic filter differing from the organic filter planted according to the invention and as described above in that the organic substrate is replaced by polluted soil. The leachate resulting from this planted organic filter is then treated in two successive stages, called vertical filters and horizontal filters and each composed of at least one organic filter planted according to the invention with vertical or horizontal filtration respectively.

For such a device for treating polluted soils, the irrigation / drying cycles of the plant-grown organic filter will be from 4 hours to several months in the case of polluted soils, preferably from 12 hours to 2 months, and particularly preferably from 1 to 2 months. order of one month.

In a preferred embodiment of the device according to the invention, it uses a closed circuit irrigation, so as to save water. In another preferred embodiment of the device according to the invention, the latter further comprises at least one planted organic filter in which the compost is a brown peat and which aims at trapping pollutants, especially metallic pollutants.

A third object of the invention is a method for treating polluted water, soil or air comprising the introduction of polluted water, soil or air into a device as described above.

Preferably, this treatment process is intended for trapping carbon dioxide with a carbon dioxide scavenging rate greater than 10% of the influx, preferably between 10 and 35%.

More preferably, and when the organic filter comprises brown peat as compost, said treatment process is intended for the trapping of heavy metals with an abatement rate greater than 90% of the incoming flows, which heavy metals are chosen from particularly preferred manner among copper, lead, zinc and aluminum.

A fourth subject of the invention relates to the use of a treatment device as described above for the trapping of dioxide carbon with a capture rate of carbon dioxide greater than 10% of the inflow, preferably between 10 and 35%.

Advantageously, said use is based on a treatment device based on brown peat as described above and is aimed at the trapping of heavy metals with an abatement rate greater than 90% of the incoming flows, which metals are chosen in a particularly preferred manner among Copper, Lead, Zinc and Aluminum.

Other features of the invention will appear in the following examples, without these constituting any limitation of the invention.

Examples

1 - Example of a device for the clearance of gaseous effluents

Figure 6 illustrates the structure of a vertical organic filter for the filtration of gaseous effluents with a flow rate of 8000 Nm3 / h. This vertical organic filter is positioned along a wall (19) from which it is isolated by a geomembrane (20). An inlet for the gaseous effluents is connected to an aeration network (13) and makes it possible to bring the gaseous effluents into the organic substrate (4) planted with European and / or tropical / desert rods (6). Between the aeration network (13) and the organic substrate (4), a vacuum (22) is maintained to ensure a good distribution of effluents. To prevent drying of the organic substrate due to the arrival of gaseous effluents, the organic substrate (4) is traversed by an irrigation network (15). Similarly, to ensure the maintenance of the organic substrate (4), it rests on a frame (21) type gabion sealed in the wall (19).

The performance of a device according to FIG. 6 is described in table V which follows: Table V

VOCs: volatile organic compounds; PM10: Particles of 10 μπι or less.

FIG. 5 illustrates the structure of another filter for the treatment of gaseous effluents in which the gaseous effluents enter via an inlet (10) at the base of the isolated soil filter by a geomembrane (2). The base of this organic filter comprises floor supports (18), in which passes the arrival of effluents (10) and on which a grating (17). On this grating (17), we successively find a

Draining layer (5), then a specific organic substrate (4) planted with European and / or tropical / desert canes (6). The gaseous effluents pass through the draining layer and then the organic substrate where they are degraded and, for some of them, accumulated. An irrigation system (15) makes it possible to carry out periods

15 at the filter and at the same time to evacuate the non-degraded pollutants (16) for further processing in other filters.

2- Example of a device for the depollution of wastewater

Figure 1 illustrates the structure of the device for treating organic material present in wastewater. This device incorporates two successive organic filters, the first of which is vertically fi ltered and the second fi ltered horizontally. Figures 2 and 3 show two possible structures of organic filters, in which an arrival of polluted water (1) brings the effluents to be treated at the level of the organic filter isolated from the ground by a geomembrane (2). The wastewater effluents then pass through the organic substrate (4) planted with European and / or tropical / desert canes (6) of a minimum height (8) before reaching the draining layer (5) which can be overcome an intermediate filter layer (13) including sand or small gravel. In all cases, the filters have a minimum thickness in organic substrate (9). To ensure good degradation of the pollutants during their passage through the filter, low aeration is provided by the collection drain (3) and a high aeration (7) is provided between the draining layer and the organic substrate.

The wastewater effluents, after treatment by passing through the first two organic filters of the device described in Figure 1, are discharged through an inlet (10) in a basin with anti-slip steps (11) and oxygenating aquatic plants (11). ). This basin is a high feed for the trapping filter downstream via a drain (3) which also serves as ventilation between two fills of the basin. This drain (3) then delivers the pretreated effluents into the organic substrate (4) of the trapping filter which is planted with European and / or tropical / tropical canes (6). The last pollutants present are degraded or accumulated in the latter filter.

The performances of such a device have been tested on two different sites and are described in Tables VI and VII which follow.

Table VI

MES: Suspended matter; COD: Chemical oxygen demand; DB05: Biological oxygen demand; MO: organic matter; NTK: Nitrogen

Table VII

concentrations

Outgoing Yield

Loads With materials Without materials With materials Without materials

Woody woody ligneous entrants

Mg / l mg / l mg / l%% parameters

PH 7.65 7.65 7.7

MES 89 25 60 71.9% 32.6%

DCO 299 125 180 58.2% 39.8%

DB05 102 32 55 68.6% 46.1%

NTK 13.1 2.5 10 80.9% 23.7%

Pt 2.7 1.7 2.5 37.0% 7.4%

Hydrocarbons 1.5 0.05 1.1 96.7% 26.7%

Total 4HAP 0.2 0.01 0.2 95.0% 0.0%

Total 6HAP 0.5 0.04 0.5 92.0% 0.0%

As 0.05 0.05 0.05 0.0% 0.0%

Cd 0.02 0.01 0.02 50.0% 0.0%

Cr 0.06 0.05 0.06 16.7% 0.0%

Cu 1.0 0.05 1 95.0% 0.0%

Ni 0.08 0.05 0.08 37.5% 0.0%

Pb 5.1 0.1 5 98.0% 2.0%

Zn 4.3 0.4 4 90.7% 7.0%

Al 7.1 0.1 6.5 98.6% 8.5%

bacteria

3,000,000 186,000 93.8%

aerobic 3- Example of a device for the remediation of polluted soils

Figure 4 illustrates the structure of a device for the treatment of organic matter present in polluted soil or sludge.

This device comprises an inlet (1) for soils or polluted sludge which causes effluents to be treated at the level of the organic filter insulated from the ground by a geomembrane (2). The level of the organic filter (14) then rises progressively as the European or tropical / desert canes (6) also rise. The latter are also chosen to have a height at maturity (8) greater than 1.2 m. During the irrigation of the filter, which can be carried out by the effluent liquid or by a complementary irrigation system, the effluent pollutants then progressively pass through the organic substrate (4) before reaching the draining layer (5). ) where is positioned a drain (10) for discharging leachate to the trapping filter. To ensure good degradation of the pollutants during their passage in the organic filter, low aeration is provided by the collection drain (3) and a high aeration (7) is provided between the draining layer and the organic substrate.

The leachates discharged by the drain (10) to the trapping filter arrive in the draining layer (5) of the latter and, as they rise, penetrate a specific organic substrate (5) of good thickness (9). planted with European and / or tropical / desert canes (6) which are also chosen to have a height at maturity (8) greater than 1.2 m.

The performance of such a device is described in Table VIII which follows: Table VIII

Charges Concentrations

Outgoing Inbound Yield

Mg / 1 mg / 1% parameters

PH 7.5 7.0

MS 8354 36 99.6%

MES 7241 25 99.7%

COD 6055 200 96.7%

BOD 1910 40 97.9%

Organic Carbon 2640 360 86.4%

NTK 211 0.5 99.8%

NH ₄ 11.4 0.08 99.3%

P total 37 8 78.4%

Claims

1. A planted organic filter for treating pollutants, which planted organic filter comprises:

- an entry for the pollutants to be treated,

- an output for non-degraded pollutants,

a) an organic substrate composed of 10-20% aggregates, which aggregates are preferably insoluble and with an irregular surface, more than 30% of plant fibers in the form of a woody material, and 20- 40% of compost containing more than 30% of ligneous material and preferably having a biological stability index (BSI) greater than 0.5,

b) which organic substrate is planted with European and / or tropical / desert canes, which cannes preferably favor a strong sequestration of carbon dioxide.

2. The organic filter plant according to claim 1, characterized in that said insoluble aggregates and having an irregular surface are selected from pozzolan, flint and siliceous sands.

3. The organic filter plant according to any one of claims 1 or 2, characterized in that said plant fibers in the form of a woody material are selected from the group bagasse sugar cane, bark nuts coconut, palm leaves, bark and especially pine bark.

4. The planted organic filter according to any one of claims 1 to 3, characterized in that said European and / or tropical / desert canes are chosen from the group comprising Acorus Calamus, Amnophila arenaria, A pelodesmos mauritanicus, Andropogon gerardii, Arundo donax sensu, Bromus inermis, Calamagrostis acutiflora, Calamagrostis arundinacea, Carex morrowii, Carex pendula, Chasmanthium latifolium, Chionochloa conspicua, Chusquea culeou, Colocasia esculenta, Cortaderia fulvida, Cortaderia richard /, Cortaderia se / loana, Cymbopogon citratus, Cyperus Cyperus giganteus, Cyperus longus, Cyperus papyrus, Cyperus giganteus, Cyperus longus, Equisetum americanum, Equisetum hyemale, Equisetum fluviatile, Equisetum maximum, Fargesia murielae, Fargesia nitida, Glyceria maxima, Hibanobambusa tranquillans, Indocalamus solidus, Indocalamus tessellatus, Juncus acutus, Juncus effusus, Leymus arenarius, Miscanthus sinensis and var., Miscanthus floridulus, Miscanthus sacchariflorus, Miscanthus giganteus, Molinia altissima, Molinia arundinacea, Molinia caerulea, Panicum virgatum, Panicum rigidulum, Papyrus papyrus, Pennisetum and var., Phalaris arundinacea, Saccharu arundinaceum, Saccharum officinarum, Saccharum ravennae, Schoenoplectus californicus, Schoenoplectus tabernaemontanis, Scirpus lacustris, Sorghum halepeus, Spartina alterniflora, Sponiopogon sibiricus, Stipa calamagrostis, Stipa splendens, Typha minima, Thysanolaena latifolia, Zizania aquatica, Zizania latifolia and Zizania palustris, Greslania rivularis, Greslania multiflora, Flagellaria sp., Scirpus subulatus, Sacharum spontaneum, Andropogan leucostachyus, Coiocasi gigantea, Typhonodorum lindlleyanum, Cyperus distans, Heliconia latisphana, Heliconia stricta and Medicago sativa.

5. The planted organic filter according to claim 4, characterized in that it comprises at least two different species of European cane and / or tropical / desert.

6. The planted organic filter according to any one of claims 1 to 5, characterized in that said compost and is rich in lignin, with a lignin content greater than 30%, preferably said compost is as defined by the standard NF U44-051.

7. The planted organic filter according to any one of claims 1 to 6 characterized in that said planted organic filter is for the trapping of pollutants including metallic and in that said compost takes the form of preriferated vegetable debris with the characteristics listed in Table IV, preferably said compost is brown peat.

8. The planted organic filter according to any one of claims 1 to 7 characterized in that said planted organic filter is intended to treat polluted soils and in that it is made without geomembrane.

9. A treatment device for the treatment of polluted water, soil or air comprising at least one planted organic filter according to any one of claims 1 to 7.

10. The treatment device according to claim 9 characterized in that it further comprises at least one planted organic filter for trapping pollutants, especially metallic, according to claim 7.

11. A method of treating polluted water, soil or air comprising the introduction of polluted water, soil or air into a device according to any one of claims 9 or 10.

12. A treatment method according to claim 11, characterized in that it is intended for trapping carbon dioxide with a carbon dioxide scavenging rate greater than 10% of the inflow, preferably between 10 and 35.

13. A treatment method according to claim 11, characterized in that it comprises a plant-based organic filter according to claim 7 and in that it is intended for the trapping of heavy metals with an abatement rate greater than 90% of the Incoming streams, which heavy metals are preferably selected from copper, lead, zinc and aluminum.

14. Use of a device according to any one of claims 9 or 10 for trapping carbon dioxide with a carbon dioxide scavenging rate greater than 10% of the inflow, preferably between 10 and 35.

15. Use of a treatment device according to claim 10 for trapping heavy metals with an abatement rate greater than 90% of the incoming flows, which heavy metals are preferably chosen from copper, lead, zinc and Aluminum.