Water filter for drawing drinking or process water from a body of water

Abstract

Water filter (1) for drawing drinking or process water from a body of water with a metallic outer wall (2) having filter openings (8), characterized in that the outer wall (2) consists of pure copper 99.9% or a copper alloy with a copper content of 85% or more.

Description

The invention relates to a water filter for drawing drinking or process water from a body of water, with a metallic outer wall having filter openings. When drawing water from lakes, rivers, or similar inland waters, or even from the sea, water filters are used. These pre-filters, also known as strainers, are positioned below the water's surface for drinking, process, or industrial water extraction. Water filters commonly found in practice often have a cylindrical housing with a sieve-like structure made of stainless steel. The mesh size of the sieve is designed to trap larger particles of dirt. Such pre-filters or water filters typically have diameters between 600 mm and 2000 mm and heights between 1000 mm and 3000 mm. Of course, these dimensions are merely examples. Water filters can be designed to be larger or smaller without deviating from the principles of the invention. The term "process water" also includes water used as a heat transfer medium for energy generation through heat extraction from a natural body of water. In this process, the process water is drawn from the external body of water—for example, a river, lake, or reservoir—passed through a heat exchanger or a heat pump, particularly a so-called large-scale heat pump, and then returned to the same or a different body of water. Here, the process water acts as a secondary heat transfer medium, absorbing the thermal energy contained in the water and transferring it to an internal heating system via the heat exchanger. To prevent solids from entering the heat exchanger, the system is equipped with a water filter. The quagga mussel (Dreissena rostriformis) is increasingly posing a problem for water filters. The quagga mussel, also known as the zebra mussel, is an invasive freshwater mussel species originally from the Black Sea region. It has spread extensively in Europe and North America and poses a significant threat to native aquatic ecosystems and infrastructure. Due to its rapid reproduction almost year-round, it forms dense mussel beds on various substrates. It colonizes and clogs water pipes, water treatment plant filtration systems, boats, and fishing nets, resulting in high cleaning, maintenance, and repair costs. In some cases, water filters must be cleaned by divers or retrieved for cleaning once or twice a year. The quagga mussel has few natural predators in foreign ecosystems. Therefore, it reproduces rapidly and uncontrollably.Once a population has established itself in the lake, it is virtually impossible to prevent it from attaching to organic and inorganic substrates. From there, they release larvae which, once they reach a size of 200 µm, adhere to a new location for settlement. The invention is based on the objective of creating a water filter of the type mentioned above in which so-called fouling is reduced. According to the invention, the problem is solved by the outer wall being made of pure copper 99.9% or a copper alloy with a copper content of 85% or more. It has been found that copper, with its antimicrobial properties, is toxic to microorganisms, particularly damaging to cells. This prevents organisms from colonizing copper surfaces. The accumulation of unwanted materials on a solid surface, typically in a liquid, is known as fouling, which is reduced or prevented by the copper. Furthermore, copper ions are released from the outer wall, leading to antifouling in the immediate vicinity of the water filter. This antifouling on the outer wall and in the surrounding area also reduces barnacle growth in downstream components of the system, particularly in water pipes, pumps, and similar equipment. The invention is advantageous in that no mussel growth, in particular no growth of quagga mussels, is detectable on the water filter and the adjacent system components. Since there is no reduction of the open filter area due to mussel growth, a constant water withdrawal is possible, potentially with a constant pump output. Cleaning due to fouling is less frequent or even unnecessary. No spawning of mussel larvae and a reduction in mussel growth in the downstream system components were observed in the area of ​​the water intake point where the water filter is located. Due to the manufacturing process of the water filter's outer wall, it is corrosion-resistant to both lake and river water. With a copper content of 85% or higher in the copper alloy, beneficial effects, as described above, could be observed. Preferably, the outer wall is made of sheet metal with punched and / or embossed filter openings. The filter openings are arranged and dimensioned such that a flow velocity of approximately 1.0 to 0.05 m / s can be achieved when water is drawn in. The geometry of the filter openings can be chosen almost arbitrarily, however, it is advantageous for the filter openings to be round, polygonal or slotted. In some embodiments, the slotted filter openings feature a slot bridge. This design reduces the risk of foreign matter becoming trapped in the filter openings compared to a design without a slot bridge. Alternatively, the outer wall can be made of wire mesh or sieve fabric. These designs are also suitable for manufacturing the outer wall of the water filter, whereby, of course, the required flow velocities for water intake must be taken into account during the manufacturing and dimensioning of the wire mesh or sieve fabric, which a specialist can easily accomplish. To remove contaminants from the water filter, the outer wall has been modified with a cleaning opening. This cleaning opening is conveniently designed as a manhole, allowing for internal inspection of the water filter, for example, using a submersible robot. It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations. The scope of the invention is defined solely by the claims. The invention will be explained in more detail below using exemplary embodiments with reference to the associated drawing. It shows: Fig. 1 a side view of a water filter according to the invention, Fig. 2 a top view of the water filter according to Fig. 1, Fig. 3 a bottom view of the water filter according to Fig. 1, Fig. 4 an enlarged view of detail IV according to Fig. 1, Fig. 5 a side view of the representation according to Fig. 3, Fig. 6 enlarged views of detail IV according to Fig. 1 in alternative embodiments. Fig. 9 The water filter 1, also called a pre-filter or strainer, has a metallic outer wall 2, which is composed of a cylindrical base body 3, an attached closure part 4 that closes a cleaning opening 6 designed as a manhole 5, and a connection flange 7 for coupling to a piping system (not shown). Internal inspection of the water filter 1 is possible through the cleaning opening 6 designed as a manhole 5. The entire outer wall 2 is made of a sheet 10 consisting of pure copper or a copper alloy with a copper content of at least 85% and, in particular, between 90% and 99.5%, in order to exert an antimicrobial effect that prevents fouling. For flow through the outer wall 2, filter openings 8 are dimensioned such that a flow velocity of, for example, 0.1 to 0.05 m / s can be achieved when water is drawn in. The filter openings 8 can have any geometry, for example, as shown in Figs. 4 and 5, and can be slot-shaped and provided with a slot bridge 9. This design proves advantageous because the jamming of foreign matter in the slot-shaped filter openings 8 with slot bridge 9 is reduced compared to a design without a slot bridge. The filter openings 8 according to Fig. 6 are essentially rectangular and designed without a slot bridge, which simplifies manufacturing compared to the variant with slot bridge 9. The filter openings 8 according to Fig. 7 are round and the filter openings 8 according to Fig. 8 are polygonal and punched out of the sheet metal 10. The filter openings 8 according to Fig. 9 are part of a sieve fabric 11 or perforated sheet, which forms at least substantially the outer wall 2 of the water filter 1. Reference sign 1 Water filter 2 Outer wall 3 Base body 4 Closure part 5 Manhole 6 Cleaning opening 7 Connection flange 8 Filter opening 9 Slotted bridge 10 Sheet metal 11 Filter mesh

Claims

Water filter (1) for drawing drinking or process water from a body of water with a metallic outer wall (2) having filter openings (8), characterized in that the outer wall (2) consists of pure copper 99.9% or a copper alloy with a copper content of 85% or more. Water filter (1) according to claim 1, characterized in that the outer wall (2) is made of a sheet (10) with punched and / or embossed filter openings (9). Water filter (1) according to claim 1 or 2, characterized in that the filter openings (8) are round, polygonal or slotted. Water filter (1) according to one of claims 1 to 3, characterized in that the slot-shaped filter openings (8) have a slot bridge (9). Water filter (1) according to claim 1, characterized in that the outer wall (2) is made of a wire mesh or sieve fabric (11). Water filter (1) according to one of claims 1 to 5, characterized in that the outer wall (2) has a cleaning opening (6). Water filter (1) according to claim 6, characterized in that the cleaning opening (6) is designed as a manhole (5).

Images