Method and means for water treatment

Abstract

The present invention relates to a fiber material, and its use in installations that purify water, wherein the fiber material comprises a multitude of free polymorphic fibers, wherein at least 95% of the fibers have a particle size between 0.01 and 25 mm, and wherein the fibers are obtained by shredding or grinding a stone wool substrate that is suitable for use in the hydroponics of crops. The invention also relates to a method for purifying water and a device provided with the fiber material as described herein for treating water.

Description

[0001] METHOD AND MEANS FOR WATER TREATMENT

[0002] TECHNICAL FIELD

[0003] The invention relates to a fiber material, suitable for use in the filtration and / or purification of water. The present invention also describes a device suitable for purifying water such as wastewater.

[0004] PRIOR ART

[0005] In rural areas, there is a lack of sufficient sewerage facilities as a result of fragmented building policies and ribbon development. As a result, a significant part of the territory remains unconnected to sewerage. Globally, 45% of wastewater is discharged untreated, which directly contributes to a negative impact on water quality as untreated wastewater ends up in surface water.

[0006] This situation makes it difficult to achieve the water quality objectives of the European Water Framework Directive, which states that water must be clean and healthy by 2027. The distance between existing sewer networks and homes / businesses in rural areas is often too great to efficiently discharge wastewater via traditional sewer systems, resulting in high costs and technical challenges. Therefore, alternative solutions are needed.

[0007] In this case, small-scale water treatment systems, particularly those based on natural solutions such as plant filters, are becoming increasingly important. These solutions not only provide an effective way to purify wastewater, but they are also supported by a growing recognition of their sustainability and environmental performance.

[0008] However, to fully realize the potential of biological water treatment systems, continuous improvement is necessary. One aspect in which improvement is needed concerns the substrates used in plant filters, a common component of biological treatment systems. To date, substrates such as lava, lignite fibers, and expanded clay are used. However, these materials have disadvantages, such as degradation over time, a lack of durability, or the need for the addition of aeration to ensure effective purification. There is therefore a need for the development of new, sustainable substrates for plant filters.

[0009] Substrates such as stone wool are sometimes described in the context of water treatment, see JP2001104993, US5395533, W02004108603 or US4388192. However, none of these documents address the context of a plant filter, or can be applied in a plant filter.

[0010] A plant filter requires a substrate to grow on. This substrate must provide a good water filtration system as well as a healthy growth medium for plants. This means it must be resistant to clogging and loss of stability, and nutrient fluctuations must be minimal. At the same time, it must provide sufficient water and oxygen for the roots and microbial activity in the root zone.

[0011] The present invention aims to provide at least a solution to some of the above- mentioned problems or disadvantages.

[0012] SUMMARY OF THE INVENTION

[0013] In a first aspect, the invention relates to a fiber material according to claim 1.

[0014] The fiber material described herein is derived from the waste industry and thus contributes to a circular economy. In addition, the fiber material originating from hydroponics undergoes activation, making it better suited for use in a plant filter. During activation, nutrients and carbon sources are absorbed into the fiber material. An important advantage of using a fiber material based on a stone wool substrate is the potential for longer use of the material. Stone wool is an inert product that does not easily degrade, even after decades of water purification. As a result, the service life of water treatment systems is extended, resulting in a reduction of waste and more efficient use of resources.

[0015] Due to the light, flexible nature and high sponge-like behavior of the fiber mass, the fiber material as described herein is extremely suitable as a growth substrate for microorganisms needed for the process of biological water treatment.

[0016] In addition, the use of a stone wool-based substrate contributes to improved overall operational efficiency of water treatment systems. The unique ability of ground stone wool to form a temporary water zone during periodic percolation of water and then draw in air minimizes the need for intensive aeration. This leads to lower energy costs and a reduced ecological impact of the treatment process.

[0017] Moreover, the use of a stone wool-based substrate results in a reduction of the waste volume associated with traditional water treatment systems. Because stone wool does not easily degrade, there is less need for regular replacement and removal of substrate materials. This contributes to more efficient use of resources and reduces the environmental burden of the treatment process.

[0018] The invention also relates to a use according to claim 15, a method according to claim 19, and a device with the fiber material according to claim 22.

[0019] DESCRIPTION OF THE FIGURES

[0020] Figure 1 shows a schematic representation of a filtration system for use in a water treatment system according to an embodiment of the present invention.

[0021] DETAILED DESCRIPTION

[0022] The invention relates to a fiber material that is suitable for use in biological water treatment systems for purifying water and its use in installations.

[0023] Unless otherwise defined, all terms used in the description of the invention, including technical and scientific terms, have the meaning as commonly understood by those skilled in the technical field of the invention. For a better understanding of the description of the invention, the following terms are explicitly explained.

[0024] In this document, "a" and "the" refer to both the singular and the plural, unless the context presupposes otherwise. For example, "a segment" means one or more than one segment.

[0025] When "approximately" or "around" is used in this document with a measurable quantity, a parameter, a duration or moment, and the like, variations of + / -20% or less are meant, preferably + / -10% or less, more preferably + / -5% or less, even more preferably + / -1% or less, and even more preferably + / -0.1% or less than and of the cited value, insofar as such variations are applicable in the described invention. However, it should be understood that the value of the quantity for which the term approximately" or "around" is used is itself specifically disclosed.

[0026] The terms "comprise," "comprising," "consist of," "consisting of," "provided with," "include," "including," "contain," "containing," are synonyms and are inclusive or open terms that indicate the presence of what follows, and which do not exclude or prevent the presence of other components, characteristics, elements, members, steps, as known from or disclosed in the prior art.

[0027] The recitation of numerical ranges by the endpoints includes all integers, fractions, and / or real numbers between the endpoints, including these endpoints.

[0028] The terms "purification" or "treatment" as described herein relate to the treatment of water by mechanical, biological, and / or chemical processes, preferably so that the water subsequently meets a certain (quality) standard.

[0029] The term "filter" as used herein refers to a process in which contaminants present in water are removed, by means of a physical barrier or chemical process. Consequently, filtering can be considered a form of treatment.

[0030] The term "biological water treatment system" in the present invention refers to a system that uses biological processes to purify wastewater.

[0031] The term "plant filter" refers to a type of water treatment system in which plants, usually helophytes, are used to purify wastewater.

[0032] The term "fiber material" in the present invention refers to a material consisting of a multitude of polymorphic fibers.

[0033] The term "polymorphic fibers" refers to fibers that can take on different shapes.

[0034] The terms "diabase" and "basalt" refer to specific types of igneous rock.

[0035] Basalt, a common rock on earth, is a mafic igneous rock that mainly consists of minerals such as plagioclase, pyroxene, and sometimes olivine. Characteristic of basalt is the fine-grained texture, in which individual minerals are not easily distinguishable to the naked eye. The rock usually has a dark color ranging from black to dark gray, due to the presence of dark minerals such as pyroxene and magnetite. Basalt typically forms by the rapid cooling of lava at the earth's surface or under water and is often found in volcanic areas, oceanic crust, and some continental regions. Diabase is a mafic igneous rock, but it generally contains more calcium-rich plagioclase and less olivine than basalt. Diabase usually has a fine- to medium-grained texture, with individual minerals sometimes distinguishable to the naked eye. The color of diabase is similar to basalt, but can be slightly lighter due to the presence of calcium-rich plagioclase. Diabase usually forms deep below the earth's surface by the slow cooling of magma. It is often found in deep dikes, intrusions, and as xenoliths in lava.

[0036] The term "stone wool" refers to a type of insulation material produced from molten igneous rock.

[0037] In a first aspect, the invention relates to a fiber material, suitable for purifying water, for example via plant filters, wherein the fiber material comprises a multitude of loose, polymorphic fibers, wherein at least 95% of the fibers have a particle size between 0.01 and 25 mm, and wherein the fibers are obtained by shredding or grinding a stone wool substrate for use in hydroponics of crops. In one embodiment, the rock wool substrate is diabase or basalt based.

[0038] To date, in such processes, mainly substrates such as lava, lignite fibers, and expanded clay are used. However, these materials have disadvantages, such as degradation over time, less favorable growth of microorganisms, and the need for the addition of aeration to ensure effective purification.

[0039] The fiber material as described in the present invention has the advantage that, due to its inert nature, it is particularly durable in use, and is also a perfect substrate for water purification. The ability of ground stone wool to form a temporary water zone during periodic percolation of water such as wastewater and then draw in air minimizes the need for intensive aeration that is often present in other water treatment systems. These 'sponge' properties of the fiber material make it an ideal substrate for use in, for example, plant filters.

[0040] The fiber material also fits into a circular use, as it is derived from a stone wool substrate that was used in the hydroponics of crops. More specifically, it concerns a basalt- or diabase-based stone wool substrate. It was found that such a material offers unique advantages over the already known filter materials. The fiber material also provides a larger contact surface per volume for microorganisms that are essential for water treatment systems and therefore contains a high number of microorganisms responsible for purification. Because the fiber material is a residual product and is sustainably reused, this also has a positive impact on the ecological footprint of the installations in which it is used. The use of the fiber material also contributes to more compact water treatment systems because it is a more compact substrate than the currently used substrates in other systems such as systems with expanded clay, lava rock, etc. Because the use of the fiber material leads to more compact installations, it also lowers the threshold for choosing to implement a biological water treatment system.

[0041] Because the material has previously been used in hydroponics, it has acquired properties that are not present in "virgin" stone wool.

[0042] Virgin stone wool is stone wool that has been produced for the first time from primary raw materials (such as basalt, diabase, or limestone) without the addition of previously used or recycled stone wool material.

[0043] When stone wool is used in hydroponics, such as in the cultivation of tomatoes or other plants, it undergoes a series of physicochemical and biological changes that functionally activate the substrate, making it optimal for reuse in a water treatment system.

[0044] The fiber material has, among other things, a higher density (480-850 kg / m3) than "virgin" stone wool (45-80 kg / m3). The higher density is an important advantage, as it provides a larger surface area per volume, which promotes the adhesion and growth of microorganisms.

[0045] During the growth cycle of the plants, the stone wool is continuously in contact with nutrient solutions that contain essential macro- and micronutrients, including nitrogen compounds, phosphates, potassium, calcium, magnesium, trace elements, and organic components such as humic acids and root exudates. This interaction causes nutrients and dissolved organic substances to accumulate in the fiber structure of the stone wool, enriching the substrate with bioactive components.

[0046] In addition, biological colonization takes place. Microorganisms such as bacteria and fungi attach to the surface of the stone wool fibers and form biofilms that contribute to the breakdown and conversion of nutrients, including carbon sources. Some of these microorganisms play a role in nitrification and denitrification, processes that convert nitrogen compounds into forms that can be used by both plants and the microbial ecosystem in the water treatment system. Root growth within the substrate also results in the secretion of organic acids and enzymes, which influence the pH balance of the fiber material and increase the availability of certain minerals. The root residues left behind after harvest form an additional breeding ground for microbial life and contribute to the formation of stable organic fractions within the substrate.

[0047] Due to this exposure and enrichment during use in hydroponics, the original, inert structure of the fiber material changes into an active medium that, when reused in a water treatment system, not only functions as a physical filter but also as a source of nutrients and a carrier of microbial communities. When the activated stone wool is used in a plant filter, the accumulated nutrients are gradually released, supporting the growth of water-purifying plants. At the same time, the already present microorganisms stimulate the breakdown of organic substances and contaminants in the water. This leads to more efficient purification because both the filtration capacity and the biological activity of the system are enhanced.

[0048] Moreover, the fiber material can play a role as a substrate for rhizosphere processes, in which the roots of the plants in the filter actively interact with the microbial population to break down contaminants and absorb nutrients. The porous structure of the fiber material ensures that water is well retained and that optimal oxygen supply is provided, which is crucial for aerobic microbial processes. Because the fiber material already contains a pre-formed biological community, the start-up time of the plant filter is shortened and the system can reach stable and efficient operation more quickly. This makes it possible to reuse a residual stream from hydroponics in a circular process, in which both the remaining nutritional value and the microbial activity of the stone wool are utilized for sustainable and improved water purification.

[0049] In an embodiment, the dry matter of the fiber material comprises at least 10%, more preferably at least 9%, even more preferably at least 8%, most preferably at least 7% organic material. This organic material mainly consists of residual plant material, root exudates, and microbial biomass that have accumulated in the fiber structure during use in hydroponics.

[0050] The portion of the dry matter that volatilizes during combustion at 550°C can be measured using a Volatile Suspended Solids (VSS) test, a method used to determine the organic content of the suspended solids (TSS). It therefore mainly measures the amount of organic material in a sample, such as biomass from microorganisms, plant residues, and other organic particles. The VSS test is often used in water treatment processes to assess the biological activity and organic load of a system.

[0051] In one embodiment, the fiber material is hydrophilic. For this purpose, the fiber material can be supplemented with a surface-active agent, such as a hydrophilic binder. These binders change the surface tension of the fibers and ensure that water is attracted and spread rather than repelled. The binder may be selected from, but is not limited to, the group comprising: polyvinyl alcohol (PVA), modified acrylates, polyacrylates, polyurethanes, ethylene-vinyl acetate (EVA), polyvinylpyrrolidone (PVP), polycarboxylates, polysaccharides, alginates, carboxymethyl cellulose (CMC), hydroxypropyl methylcellulose (HPMC), starch derivatives, polyethylene glycol (PEG), polypropylene glycol (PPG), polyvinyl caprolactam (PVCL), polymaleic acid, polymaleic anhydride, silica-based binders, siloxanes, silanes, sodium silicate, potassium silicate, lithium silicate, colloidal silica, organosilanes, phosphates, phosphonates, casein, soy protein, gelatin, lignosulfonate, tannins, polyamides, polyester binders, polyvinyl chloride (PVC), polyetheramines, polyvinyl butyral (PVB), polyimides, epoxy resins, melamine-formaldehyde, urea-formaldehyde, phenolformaldehyde, resorcinol-formaldehyde, latex-based binders, polyisocyanates, polyolefins, polyvinyl esters, polycaprolactones, polydimethylsiloxane (PDMS), sulfonated polyesters, polyalkylamines, polyalkylene oxides, polyoxazolines, polyurea, polybenzimidazole, fluoropolymers, perfluoropolymers, carbodiimide- based binders, sulfur-containing polymers, thermoplastic elastomers, bio-based polymers, protein-based binders, and enzyme-modified polymers. In a preferred embodiment, the hydrophilic binder comprises an organic binder, preferably a carbohydrate such as a sugar, for example glucose, fructose, or sucrose, or polysaccharides such as starch or cellulose.

[0052] The capillary action of the hydrophilic fibers ensures that water and dissolved nutrients are efficiently transported through the substrate, giving plant roots and microorganisms access to the necessary nutrients and oxygen. This makes the fiber material particularly suitable for use in a plant filter, where balanced moisture distribution is crucial for stable biological activity and optimal purification efficiency. Moreover, the stone wool fibers in an embodiment are inert, meaning that they themselves do not retain or break down nutrients. The chemical stability of the material contributes to a reliable water management system allowing the purified water to be reused without unwanted interactions with the substrate. In short, the conditions within the water treatment systems make the stone wool substrate ideal for use: it is airy, inert, and provides a large contact surface due to the finely ground material.

[0053] In an embodiment, at least 95% of the fibers have a particle size between 0.01 and 25 mm, more preferably between 0.01 and 20 mm, more preferably between 0.01 and 17.5 mm, even more preferably between 0.01 and 17 mm, even more preferably between 0.01 and 16 mm, and most preferably between 0.01 and 15 mm. In an embodiment, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, at least 99.5%, or 100% of the fibers have a particle size between 0.01 and 20 mm, more preferably 0.01 and 15 mm. The term "particle size" refers to the size of individual particles, preferably measured by laser diffraction.

[0054] In an embodiment, the fiber material, when not yet in use in the context of purification such as filtering water, has a moisture content lower than 25%, more preferably lower than 20%, more preferably lower than 15%, more preferably lower than 10%, more preferably lower than 5%, more preferably lower than 2%. This facilitates the transport and use of the fiber material during installation of a water treatment system. The term "moisture content" refers to the amount of water in a material, measured by techniques known in the prior art, such as by moisture meters or a drying oven. In an embodiment, the fiber material can be subjected to an active or passive drying step to achieve the desired moisture content.

[0055] Because the fiber material is derived from material that was previously used for hydroponics, it is possible that contaminants are present that are undesirable in the context of further use in water purification. In an embodiment, the fiber material or the substrate underlying the fiber material will therefore first undergo a cleaning step to remove any contaminants. Such contaminants may include metal ions, originating from the hydroponics process. In an embodiment, the contaminants are selected from the group of zinc ions, cobalt ions, nickel ions, or a combination thereof.

[0056] In an embodiment, the fiber material comprises less than 1% w / w total chemical contamination, preferably less than 0.5%, preferably less than 0.25%, preferably less than 0.1%. The term "total chemical contamination" refers to the sum of all contaminants caused by unwanted ions such as, for example, cobalt, nickel, or zinc. By keeping the contaminants low, the safety and quality of the purified water is guaranteed. The substrate underlying the fiber material usually also contains a very high degree of plastics. These are of course undesirable in the context of water purification. In an embodiment, a separation step will therefore also be carried out to separate plastics and fiber material from each other. This separation can be carried out by techniques known for this purpose, such as sieving.

[0057] In an embodiment, the fiber material contains less than 0.1% w / w plastics, more preferably less than 0.05% plastics, where the plastics are defined as plastics that have a length or size greater than 5 mm. The plastic content is often higher in "virgin" stone wool (often on average 3.5% w / w).

[0058] In an embodiment, the fiber material has a pH between 4.5 and 10.0. In a preferred embodiment, the fiber material has a pH between 4.5 and 9.5, even more preferably between 5.5 and 9.0. This pH value promotes the growth of helophytes and thus improves the efficiency of water purification. An optimal pH in the fiber material is crucial because it affects the activity of microorganisms responsible for breaking down organic material and removing contaminants from the water. A good pH of the fiber material not only promotes the growth of helophytes, but also optimizes the conditions for a healthy microbiome, which ultimately results in more efficient and effective water purification.

[0059] In an embodiment, the fiber material has a softening temperature between 750 and 1150°C. This temperature range contributes to the improved stability and durability of the fiber material under extreme conditions. The fiber material may preferably have a softening temperature between 800 and 1100°C, more preferably between 800 and 1175°C, even more preferably between 750 and 1100°C, even more preferably between 825 and 1125°C, and most preferably between 850 and 1050°C. These preferred temperatures are important because they indicate the optimal conditions for the performance of the fiber material. The term "softening temperature" refers to the temperature at which a material begins to soften.

[0060] The softening temperature of a material can be determined by various methods, depending on the type of material and the available means. A commonly used method is to perform a so-called "softening test." In this test, the material is heated at a constant rate while the temperature is measured. The softening temperature is the point at which the material begins to soften and deform under the applied load. This test can be performed using various devices, such as a DSC (Differential Scanning Calorimetry) machine for polymers, or a rheometer for materials such as bitumen. The softening temperature is an important parameter for understanding the thermal properties and application possibilities of materials in various industries, such as construction, plastics processing, and the chemical industry.

[0061] In an embodiment, the fiber material has a bulk density of 300 to 1000 grams / liter, preferably between 400 and 950 grams / liter, more preferably between 500 and 900 grams / liter, even more preferably between 450 and 850 grams / liter. This ensures that the fiber material stays well in place and is easy to handle and transport. In addition, the fiber material has good water permeability at this bulk density. The higher density of the fiber material is an important advantage, as it provides a larger surface area per volume, which promotes the adhesion and growth of microorganisms. The term "bulk density" refers to the mass of a material per unit volume.

[0062] In an embodiment of the fiber material, the fibers contain between 40 and 60% SiO2 w / w, more preferably between 45 and 55% w / w, such as 47% w / w.

[0063] In an embodiment of the fiber material, the fibers contain between 10 and 20% CaO w / w, more preferably 12 to 17% CaO w / w, such as for example 16% w / w.

[0064] In an embodiment of the fiber material, the fibers contain between 10 and 20% AI2O3 w / w, more preferably between 10 and 15% AI2O3 w / w, more preferably between 12 and 18% AI2O3 w / w, and even more preferably between 14 and 16% AI2O3 w / w. In the most preferred embodiment, the fibers contain 14% AI2O3 w / w.

[0065] In an embodiment, the fiber material contains between 5 and 15% MgO w / w, more preferably between 7.5 and 12% MgO w / w, such as for example 10% MgO w / w. In an embodiment, the fiber material contains between 5 and 10% FeO w / w, such as for example 8% FeO w / w. In an embodiment, the fiber material contains between 1 and 5% Na2O w / w, such as for example 2% Na2O w / w. In an embodiment, the fiber material contains between 0.1-3% TiO2 w / w, preferably 1% TiO2 w / w. In an embodiment, the fiber material contains between 0.1-3% MnO w / w. In an embodiment, the fiber material contains between 0.1-3% K2O w / w, preferably contains 1% K2O w / w. In a second aspect, the invention relates to the use of the fiber material as described above for the purification and / or filtration of water such as wastewater. In a preferred embodiment, the water that is purified and / or filtered is rainwater, precipitation, groundwater, surface water, run-off water, or wastewater, for example originating from households, cooling water, (agricultural) industry, or public events (such as festivals).

[0066] In an embodiment of the use of the fiber material, the fiber material is a substrate for the growth of microorganisms, such as microorganisms that oxidize organic material in the water. The aerobic and anaerobic processes carried out by these microorganisms break down the organic material in the water or wastewater. The underlying biochemical processes of this breakdown are those known in the art of biological water treatment systems.

[0067] In an embodiment of the use of the fiber material, the fiber material is added to a receptacle or container to form a bed in a filtration system. The receptacle or container can have several embodiments. In an embodiment, the receptacle or container is a rectangular container. The receptacle can be provided with a waterproof membrane layer so that the water to be treated does not come into contact with the ground. In an embodiment, the container consists of two frames, an outer and inner frame between which the membrane is fixed. The frames hold the waterproof membrane in place. The waterproof membrane prevents water from leaking into the ground and forces the water to flow through the purification system before being discharged. In a further embodiment, additional filter layers (also called beds) are added to the filtration system.

[0068] In an embodiment, the additional filter layers are selected from lava rock, expanded clay, and expanded lignite. In a preferred embodiment, two additional filter layers are used, both composed of lava rock. In a preferred embodiment, the fiber layer is located between the lava rock layers, with the bottom lava rock layer serving as a drainage layer for the water. In an embodiment, the lava rock consists of particles with a particle size of 5 to 50 mm.

[0069] In an embodiment, the ratio of the thickness of the first layer of lava rock (the lower one) to the thickness of the fiber layer is between 5: 1 and 1:5, more preferably between 4: 1 and 1 :4, more preferably between 3: 1 and 1 :3, more preferably between 2: 1 and 1:2, such as 1: 1 or 1 :2. In an embodiment, the ratio of the thickness of the second layer of lava rock (the top one) to the thickness of the fiber layer is between 5: 1 and 1:5, more preferably between 4: 1 and 1 :4, more preferably between 3: 1 and 1 :3, more preferably between 2: 1 and 1:2, such as 1 : 1 or 1:2.

[0070] In an embodiment, the thicknesses of the three layers are equal or with a maximum difference of 20%, more preferably a maximum of 10%.

[0071] In an embodiment, plants are provided in the top lava layer, resulting in a root zone that helps eliminate odor nuisance. This ensures an odorless and hygienic environment and contributes to the effectiveness and acceptance of the water treatment system.

[0072] In a third aspect, the invention relates to a method for purifying water, such as runoff water, precipitation, household wastewater, or agricultural wastewater, in which the water is collected and during the treatment process the water flows through a filtration system in which the filtration system comprises a bed constructed from the fiber material as described herein. In an embodiment, the water is collected in a collection point (optionally with biological pre-treatment) such as a primary settling tank and is then led via a pump sump to a filtration system. After the water has been purified by the filtration system, it will leave the system.

[0073] In an embodiment of the method, the filtration system is a plant filter. In an embodiment of the method, the filtration system comprises a first and a second lava rock layer, and the bed with the fiber material is located between these lava rock layers. The bottom lava rock layer serves as a drainage layer for the water.

[0074] The lava rock layer at the bottom and top of the filtration system are intended to provide good distribution of water and good drainage of water. This is possible because lava is a porous rock, giving it good water permeability.

[0075] In an embodiment of the method, the filtration system does not require external aeration. In a fourth and final aspect, the invention relates to a device for purifying water, wherein the device comprises a filtration system, wherein the filtration system comprises a bed constructed from the fiber material as described herein.

[0076] Both domestic and agricultural wastewater contain organic, suspended solids and nutrients. During the purification phase in the filtration system of a biological water treatment system, these contaminants are biologically converted and removed. This process can take place within plant filters that house microorganisms on a solid substrate. Before the wastewater flows through the entire plant filter system, suspended solids are first removed in a sedimentation tank. Subsequently, the water is evenly distributed over the surface of the helophyte field, where it flows through the substrates and comes into contact with various microorganisms. This core principle is based on extensive percolation fields, within which one system contains both an oxygen-rich and an oxygen-poor zone. The microorganisms in these zones carry out various conversions, without the need for additional aeration via intensive aerators. This means that no artificial oxygen zones need to be created, resulting in minimal operational costs.

[0077] In an embodiment of the device, it comprises:

[0078] - a collection well (optionally with biological pre-treatment) such as a primary settling tank,

[0079] - a pump sump, wherein the pump sump is configured to receive wastewater from the collection well; and the aforementioned filtration system, wherein the filtration system is connected to the pump sump and configured to receive water from the pump sump.

[0080] The connection between the various components of the device is achieved by solutions known from the prior art, such as pipes and pumps. The flow of the wastewater begins when the wastewater enters a collection well such as a primary settling tank. It will then be brought to a pump sump via pipes, after which it will be brought to the filter system in a regulated manner. The wastewater enters the filtration system from the top of the system, where it is then distributed by means of pipes with perforations that are spread over the entire filter. These pipes ensure an even distribution of the water over the bed with the fiber material. In addition, there is a drain pipe at the bottom of the filtration system where the purified water ultimately leaves the filter via the bottom. In an embodiment of the device, the filtration system as described above comprises a first and a second layer of lava rock, with the bed with the fiber material located between these lava rock layers.

[0081] In an embodiment of the device, the aforementioned primary settling tank and / or pump sump is provided with one or more sensors for measuring an amount of wastewater present.

[0082] The present invention will now be described in more detail, with reference to examples or figures that are not limiting.

[0083] EXAMPLES

[0084] Example 1

[0085] Fiber material according to an embodiment of the present invention was obtained based on a substrate that was previously used in hydroponics, for example for the cultivation of tomatoes. In this hydroponics system, the substrate functions as a supporting medium for the plant roots and provides an ideal environment for growth. The substrate consists of mats of stone wool with a neutral pH. The mats have good capillary action and retain moisture evenly. This substrate consists mainly of silica.

[0086] After harvesting the tomatoes, the substrate is collected and undergoes a cleaning process to remove organic residues and contaminants. The material is then shredded into fine fibers and dried to remove excess moisture. This drying process helps maintain the integrity of the fibers and prevents possible microbial growth during storage and transport. The result is a clean and dry fiber material that is suitable for further processing and use in various applications, including water treatment systems such as the plant filter. These careful steps of collecting, cleaning, shredding, and drying are essential to ensure the quality and effectiveness of the fiber material for optimal performance in water treatment processes.

[0087] The technical specifications of the obtained fiber material

[0088] Mineralogical: amorphous silicate

[0089] Physical form: dry powder

[0090] Particle shape: polymorphic

[0091] Particle size: 0-15 mm Color: yellow-brown

[0092] Moisture content: <2% pH: min 5.5 max 9.0 softening temperature: 850-1050°C

[0093] Bulk density: 400-850 g / L

[0094] Chemical composition:

[0095] SiO247%

[0096] CaO 16%

[0097] AI2O3 14%

[0098] MgO 10% FeO 8% Na2O 2% TiO21% MnO21% K2O 1% Plastics <1% Zn<l% Ni< 1%

[0099] DESCRIPTION OF THE FIGURES

[0100] Figure 1 illustrates a filtration system being a plant filter (1) that forms an essential part of a water treatment system. This plant filter uses a fiber material (4) as described in Example 1 that provides an ideal habitat for microorganisms to purify water. The filtration system is placed in a container (7) that is lined on the inside with a waterproof membrane (2). This prevents wastewater from leaking into the ground and forces the water to flow through the purification system before being discharged. At the bottom of the container is a first layer of lava rock (3). This layer serves as a support for the entire system and helps to evenly distribute the water flowing through the system. On top of the lava rock is a layer of the fiber material as described herein (4). This material provides a large contact surface for microorganisms to adhere to and grow. The microbiome that forms on these fibers consists of various microorganisms responsible for breaking down and removing contaminants (such as organic waste) in the water. On top of the fiber material, another layer of lava rock (5) is placed. This layer helps stabilize the fibers and ensures that the water is evenly distributed throughout the purification system. On top of these three layers of rocks, plants (6) are placed, preferably helophytes. The water enters the plant filter via the top of the system, where it is then distributed by means of pipes with perforations that are spread over the entire filter. These pipes ensure an even distribution of the water over the bed with the fiber material. In addition, there is a drain pipe at the bottom of the filtration system where the purified water ultimately leaves the filter via the bottom. The plant filter is in contact with a pump sump via pipes (not shown in the figure), which provides the supply of water to the system. At the same time, a drain pipe is installed to discharge the purified water (not shown in the figure). This combination of inlet and outlet systems ensures efficient circulation of water through the filtration system, whereby the plant filter is optimally used for the purification of water and the maintenance of a healthy aquatic ecosystem.

Claims

CLAIMS1. A fiber material, suitable for use in purifying water, wherein the fiber material comprises a multitude of loose, polymorphic fibers, wherein at least 95% of the fibers have a particle size between 0.01 and 25 mm, and wherein the fibers are obtained by shredding or grinding a stone wool substrate used in the hydroponics of crops.

2. The fiber material according to claim 1, characterized in that the fiber material comprises a dry matter, wherein the dry matter comprises at least 10% organic material, measured by a Volatile Suspended Solids test.

3. The fiber material according to any of the preceding claims, characterized in that the fiber material is hydrophilic.

4. The fiber material according to any of the preceding claims, characterized in that the stone wool substrate is diabase- or basalt-based.

5. The fiber material according to any of the preceding claims, characterized in that the fiber material is derived from a stone wool substrate that was previously used in the hydroponics of crops.

6. The fiber material according to any of the preceding claims, characterized in that the fiber material has a moisture content lower than 20%.

7. The fiber material according to any of the preceding claims, characterized in that the fiber material comprises less than 1% w / w of a contaminant, wherein the contaminant is selected from the group of zinc ions, cobalt ions, and / or nickel ions.

8. The fiber material according to any of the preceding claims, characterized in that the fiber material contains less than 0.1% w / w plastic.

9. The fiber material according to any of the preceding claims, characterized in that the pH of the fiber material is between 4-10.

10. The fiber material according to any of the preceding claims, characterized in that the fiber material has a softening temperature between 750 and 1150°C.

11. The fiber material according to any of the preceding claims, characterized in that the fiber material has a bulk density of 300 to 1000 grams / liter.

12. The fiber material according to any of the preceding claims, characterized in that the fibers contain between 40 and 60% SiO2 w / w.

13. The fiber material according to any of the preceding claims, characterized in that the fibers contain between 10 and 20% CaO w / w.

14. The fiber material according to any of the preceding claims, characterized in that the fibers contain between 10 and 20% AI2O3 w / w.

15. Use of the fiber material according to any of claims 1 to 14 for the purification and / or filtration of water such as wastewater or precipitation in a plant filter.

16. The use of the fiber material according to claim 15, wherein the water originates from households, (agricultural) industry, precipitation, or public events.

17. The use of the fiber material according to any of claims 15 and / or 16, wherein the fiber material is a substrate for the growth of microorganisms.

18. The use of the fiber material according to any of claims 15 to 17, wherein the fiber material forms a bed in a filtration and / or purification system with which the water comes into contact.

19. Method for purifying water, such as household wastewater or agricultural wastewater, wherein the water is collected and during purification and / or filtration the water flows through a filtration system, characterized in that the filtration system comprises a bed constructed from the fiber material according to any of claims 1 to 14, and wherein the filtration system is a plant filter.

20. The method according to claim 19, wherein the filtration system comprises a first and a second lava rock layer and wherein the bed with the fiber material is located between these lava rock layers.

21. The method according to any of claims 19 to 20, wherein the filtration system does not require external aeration.

22. Device for purifying water, wherein the device comprises a filtration system, wherein the filtration system comprises a bed constructed from the fiber material according to any of claims 1 to 14 and wherein the filtration system is a plant filter.

23. The device according to claim 22, comprising:- a collection point such as a primary settling tank, a pump sump, wherein the pump sump is configured to receive water from the collection point; and the aforementioned filtration system, wherein the filtration system is connected to the pump sump and configured to receive water from the pump sump.

24. The device according to any of the preceding claims 22 to 23, wherein the filtration system comprises a first and a second lava rock layer and wherein the bed with the fiber material is located between these lava rock layers.

25. The device according to any of the preceding claims 22 to 25, characterized in that the aforementioned collection point and / or pump sump is provided with one or more sensors for measuring an amount of water present.

Images