CZ2480U1 - Device for washing filters, particularly filters formed by floating layer particularly wastewater treatment plant filters - Google Patents

Description

Technical field

The technical solution relates to a device for washing filters, in particular filters consisting of a floating filter layer in waste water treatment plants.

Background Art

Floating filters, made up of eg expanded polystyrene granules, are used mainly in wastewater treatment plants to capture the fine solid fraction that has remained in the settled water after the coarse flakes have been drained. In the filtration process, dirt is deposited on the granules and filtered water is collected over the filter layer. The filter is gradually clogged and it is necessary to get rid of dirt. This is done by rinsing with filtered water, which is allowed to flow through the filter for some time against the filtering direction, while the wash flow is several times greater than that of filtration. A clogged filter puts more water in the water flow than a clean filter, and when the filter becomes clogged, the water pressure in front of the filter increases. This is used to start the washing process.

Known filter washing devices consist of a valve or slide on a large diameter discharge pipe and a fluid pressure sensing device in front of the filter to give the valve or slide a pulse to open when the pressure upstream of the filter reaches a specified value.

Particular demands are placed on the filter washing device in particular in two ways: They are required to run at full flow of wash water in the shortest possible time and to keep the minimum allowable level in the treatment plant with great precision. If the level drop stops, the floating filter is washed out of the treatment plant.

In known flt washing devices, these conditions can only be met at the cost of using expensive high-speed valves and sophisticated control technology.

The aim of the technical solution is therefore to create a simple yet reliable automatic filter washing device, which is associated with minimal production costs.

The essence of the technical solution

The object of the present invention is to provide a device for washing floating filters, in particular wastewater treatment plants, which consists of an ascending pipe interconnected by an overflow with a downward conduit comprising a vertically oriented loop, the downward pipe being connected to the atmosphere via a drive valve. interconnected with the surface sensor, the overflow being connected to the interior of the treatment plant reactor by an aeration tube at a desired minimum level.

Picture on the drawing

The technical solution will be further elucidated by means of a drawing in which the figure represents a complete filter washing device in a configuration with a schematic representation of a waste water reactor.

Example of execution

A device for washing the filters consists of a riser 1 and the down pipes 2 which are interconnected through the second weir In the middle of the descending vertical pipe is formed by the loop 4. In the upper end of the descending loops £ _x pipe connected to the atmosphere through an electrovalve 5 electrically connected with level sensor 6 at the bottom of the treatment plant reactor. The inner space of the overflow 2 ^e j aerating pipe 7 connected to the reactor chamber cleaning.

The filter washing device is shown in a schematic representation of a treatment plant reactor consisting of a cylindrical vessel 8, a built-in 9, a filtration layer 10, and a filtered water supply space 11. 12 is the raw water inlet to the reactor, 13 is the sludge exhaust, and 14 is the filtered water outlet from the reactor.

Crude water with admixed flocculants enters the reactor through inlet 12. At the bottom of the cylindrical vessel 8, the coarse flakes are freed. The dewatered water then flows upward through the filter layer 10 into the filtered water supply space 11. As pollution of the filter layer 10 increases, its resistance increases and the pressure in front of it increases. This leads to an increase in the level of the level sensor 6, whose electrodes are energized by the electrovalve 5, which releases the overpressure in the downward conduit 2. column of water flowing from the reactor.

When washing, the level in the filtered water storage space 11 decreases rapidly, the water rinses the filter layer 10. As soon as the level reaches the mouth of the aeration pipe 7 located at the bottom of the storage space 11, the air will penetrate through the vent pipe 7 into the overflow space 2 ^and aerate it to interrupt the water column in down pipe 2 and end washing. It will

Also, as a result of the continuous feed of raw water into the reactor, the level of filtered water in the storage space 11 and thus in the ascending pipe 1 rises. The remaining water in loop 4 is ejected into the uplink arm of the loop 2 by overpressure γ. as long as the level difference differences between the storage space 11 and the uplink pipe 1 on one side and the uplink arm of the loop 2 and the descending pipe 1 on the other side are not equalized.

The described device finds use where it is necessary to jump the liquid level to a predetermined level, especially when washing filters in a sewage treatment plant.

Claims (1)

RIGHT TO PROTECT Apparatus for washing filters, in particular floating filters of sewage treatment plants, characterized in that it consists of an ascending pipe (1) interconnected by an overflow (3) with a downcomer (2) comprising a vertically oriented loop [4], a downcomer (2) above the loop (4) communicates with the atmosphere via a valve (5) with a drive connected to the level sensor (6), the overflow (3) communicating with the interior of the treatment plant reactor through an air tube (7) opening at the desired minimum level.