SAID STRUCTURE DRAINING AWAY FILTERED WATER

The subject of the invention is a structure draining away filtered water from under the substrate of a water tank, especially an aquarium, and a bottom bio-reactor with the structure draining away filtered water.

The gravel filters that are known in the water supply engineering are constructed on grounds of a reverse filter, that is the filter containing a material of low porosity permeating water from a water inlet, that is at the top of a deposit, and of gradually higher porosity down the deposit. The lower, more coarse layers of the deposit do not participate in purification of the incoming water, but support only the superimposed finer-grained layers. At the bottom of the filtering deposit there is a drainage in the form of perforated pipes sucking the seeping water. The aim of using this type of the filters is to purify water mechanically from the suspended solids.

The filters using a substrate of an aquarium as a filtering medium are known in fishkeeping as the filters intended to keep water quality. Generally, they consist of a rigid grate laid on the bottom of a tank, from under which is water drained away by sucking. The gravel on the grate is coarse enough to hold on the grate. The fine-grained layers are unwelcome in the substrate on the grate.

There are the known solutions that rely on existence of a layer made with gravel material in an aquarium substrate, but incorporating high porosity in the grains, that is open for water flow or diffusion, which coarse material can be held by a grate or the perforated bottoms of containers. A device for water purification with use of the formed charcoal from pyrolysis is known from the patent application US 2006/0054099. These shapes are manufactured by drying, forming and carbonizing of the organic substances produced by the food industry as the wastes. They have the shape of pellets or grains, which are placed on a separate grate constituting the body of the bottom filter or a casing constituting a container. The pellets or grains constitute the filtering layer, which has no coherent structure, is loose and is not finegrained, as well as is limited with the rigid structures like a grate or perforated plate.

A solution is known from the patent description PL 214726, namely an aquarium filtering insert and an aquarium bio-reactor including a preliminary deposit constituting the aquarium substrate that may be piled up with the fine-grained material. The filtering insert has a form of a rigid, coherent, thick plate shape made of charcoal with the preserved vessel structure of wood, out of which was the charcoal shape produced by pyrolysis, whereas the micropipes of the vessels inherited from the structure of wood lead in the vertical direction through the shape, allowing homogeneous laminar seeping of water and providing the substrate for moderate colonisation (shielded with the preliminary bed) by the useful microorganisms.

The aim of the invention is to introduce the solution enabling use of the simple low- processed materials as the water purification medium, with concurrent enrichment of water with the missing ingredients. The essence of the solution according to the invention consists in that the structure includes the susceptible diaphragm consisting of a material that is permeable for water but retains the grains of a loose medium, and that is placed on brackets, whereas the diaphragm constitutes an element separating the superimposed substrate from a void space under the diaphragm through which water flows freely to the inlet of the duct draining away the water.

The own surface of the diaphragm between the spots or segments of suspension is larger than the surface covered with the structure, constituting the surface surplus of the diaphragm after piling it with the substrate oriented downwards.

A flaccid and simultaneously inextensible well fabric constitutes the diaphragm. The local pillars or longitudinal bars constitute the brackets for the diaphragm. The brackets in the form of the local pillars are scattered advantageously and support the diaphragm in the form of the centered honeycomb.

The essence of the bio-reactor according to the invention consists in that the bio-reactor has the structure for draining away the filtered water, equipped with the susceptible diaphragm of a material permeable for water but retaining the grains of a loose medium, located on the brackets, whereas the diaphragm constitutes an element separating the superimposed substrate from the space under the diaphragm, through which flows the water to the inlet of the duct draining away the water, whereas in the bottom part of the substrate, over the diaphragm, the bio-reactor contains at least one layer of the powdered loose fine-grained materials of the large internal surface of the material that constitutes the outer surface of grains, whereas at least a half of the mass composition consists of the grains not greater than 0,25 mm.

At least one layer of the bottom part of the substrate is made of pure aluminum hydroxide or contains aluminum hydroxide.

At least one layer of the bottom part of the substrate is constituted by clay rich with iron, or laterite, or pure iron oxide or iron hydroxide; at least one layer of the lower part of the substrate may be constituted also by powder of calcium carbonate or diatomaceous earth.

Advantage of the solution according the invention is enabling to use the dusty powders as water purifying medium, eliminating technologically sophisticated shapes or pellets with the specific porosity that are placed in the specific containers with perforated walls. The implemented dusty powders as the purifying medium do not require any service, regeneration or replacement of any material insert. At the same time it is not necessary to dedicate significant space for the equipments or pools with the filtrating medium.

The solution according to the invention is presented by an example of execution in the drawings, in which Fig. 1 shows a scheme of an aquarium with the structure, Fig. 2 shows the support of the diaphragm of the structure with local pillars in a shape of the centered honeycomb.

The invention incorporates the structure draining away water from under the bottom substrate in the water container like an aquarium or a pond; and the bottom bio-reactor with the specially selected materials piled on the mentioned structure as the bottom part of the substrate of the water container, that allows to purify or to supplement composition of water seeped through the substrate and drained away from under the substrate of the water container, in the oxygen or non-oxygen environment working conditions, utilising the chemical and biological processes, especially by maintaining and utilising colonisation of the substrate by the oxygen and non-oxygen microorganisms.

The structure draining away the filtered water in the aquarium incorporates the bottom plate 1 that constitutes the construction bottom of the structure and the brackets 2 located on the plate that constitute the supportive elements for the diaphragm 3. The brackets 2 may have the shape of local pillars or longitudinal bars. Arrangement of the local pillars may have the form of the centered honeycomb 10 as shown in Fig. 2

Between the floor plate 1 and the diaphragm 3 there is the void under-the-diaphragm space 4, through which can water flow freely towards the inlet of the duct draining away the water. Water can be drained away in order to pour it back to the container as the treated water, or in order to another use, e.g. as the treated drinking water.

A flaccid and simultaneously inextensible well fabric constitutes the diaphragm 3. The own surface of the diaphragm 3 between the spots or segments of suspension with the supports 2 is larger than the surface covered with the structure, constituting the surface surplus 5 of the diaphragm 3 after piling it with the substrate oriented downwards.

In the advantageous example the diaphragm 3 is made of the dense and durable fabric in the type of the well baize woven of the nylon strand. Using such material for the diaphragm enables its easy wrinkling, that enlarges advantageously the border area surface of the device or differentiates advantageously thickness and thus the three-dimension flow field, as well as the microbiological and chemical function of the substrate layers lying on the diaphragm. Further, it allows small movements of the diaphragm, including movement of the individual fibers relatively to each other, out of which is it woven, and of the materials constituting the substrate lying on the diaphragm. The movements are advantageous for reorganisation of the structure, that recreates the permeability, that was lost during the previous exploitation, of the water seeping through the substrate and diaphragm.

The material of the diaphragm 3 is woven thickly and tightly, enabling it to retain the fine grains of the loose superimposed substrate. Retaining the even finer grains functions in a reverse filter that forms due to water flow.

The structure in the application for the bio-reactor is located in the lower part of the container, in the discussed example in the lower part of the aquarium. Over the diaphragm 3 there is a lower part of the substrate 6, over which is the upper part of the substrate 7, over which is the water zone 9 of the container.

In the lower part of the substrate 6, over the diaphragm 3, the bio-reactor contains at least one layer 8 of the dusty loose fine-grained materials with high inner surface of the material of the layer that constitutes the outer surface of grains. At least a half of the mass composition consists of the grains not greater than 0.25 mm. Over the layer 8 of the dusty materials is located the upper part of the substrate 7, for example in the form of sand or gravel.

The unusual use, for the filtrating structures, of the layer 8 of the dusty materials for the substrate lying on the diaphragm 8 (assuming the low speed of water filtration from the beginning through the bio-reactor) enables to achieve a large contact surface between the seeping water with the chemically active solid substances. At the same time, the high resistance is achieved against loss of permeability due to the microorganisms' expansion, because volume of the porous space, that takes part as the stream conveying space in seeping of water and at the same time is easily available (directly or nearly directly) for colonization by these microorganisms, is large and can advantageously exceed biomass quantity of these microorganisms that are able to stay alive in the given conditions.

Typically, the water container (an aquarium or a pond), in which the bottom bio-reactor acts, has the substrate typical for such containers in the upper part that is the top part, for example sand in a pond, coral sand in a marine aquarium, as well as the substrate layers specific for the bio-reactor below the regular substrate, as the lower part of the substrate, piled on the diaphragm 3.

Advantageously, for the marine aquarium there will be, coming from the top, a layer of powder of precipitated calcium carbonate, a layer rich with aluminum hydroxide, possibly a layer rich locally with iron oxides or hydroxides, a layer of precipitated calcium carbonate. For the fresh water aquarium or pond, there will be a layer of diatomaceous earth, a layer rich with aluminum hydroxide, possibly a layer rich locally with iron oxides or hydroxides, a layer of diatomaceous earth, possibly a layer of sand directly on a diaphragm.

The layer rich with the iron compounds may be a layer of clay rich with iron, a layer of laterite, or a layer of pure iron oxide or hydroxide. The materials are specified here in the order of price and efficiency in water purification from phosphates or arsenates.

The layer rich with iron not created originally out of iron hydroxide gets chemical activity of the bond of phosphates and arsenates mainly due to activity of the microorganisms.

Depending on various conditions, other materials of the bio-reactor are also useful, e.g. half-burnt dolomite that absorbs phosphates and silicates can be used. In other applications, powder of calcium carbonate or diatomaceous earth alone may be sufficient.