SU44189A1 - Device for supplying washing with water for drainage of low resistance of the fast filter - Google Patents

Description

The present invention relates to the field of water supply to populated areas and industrial enterprises, namely to the field of improving water quality by purifying it from suspended solids and coloring.

At present, the common method of purifying drinking water is coagulation settling and filtration. The process of settling with the use of chemical reagents and the introduction of recent design improvements is considered to be developed quite fully and in any case is more perfect than the filtering process.

In recent years, fast (American) filterless filters with low resistance drainage in the form of ribbed boards, which form a grid with 50% gaps in the useful area of the filter, have received the most application in the filtering technique.

Both the design of the filters and the design of the drains, which are the most significant part of them, are currently borrowed from foreign practice, despite their widespread use under Alliance conditions. There are 2-3 domestic drainage constructions. Trust "Kommunstroy, prof. S.V. Moiseev and the trust “Vodokanalizatsiya are private fragments of a common problem.

The constructions of these constructions (according to literary sources) partly confirm what has been said above and recognize the necessity of systematic study of filtration and washing processes in order to substantiate selected systems, as well as to find new more advanced methods.

As a rule, all drainage systems, high resistance, are complex and require the use of metal. In view of this, in allied practice, drainage drains of weak resistance with or without horizontal compensation, made mainly of wood, are considered to be the most acceptable.

The technical conditions for constructing drains of weak resistance are mainly reduced to a single requirement that ensures uniform washing of the filter loading filter sand, with an average washing intensity of 10 to 12 liters per second per 1 .m with a washing time of 3-5 minutes and with an average free head over the bottom of the filter in b-10 m of water column.

Here, washing refers to the removal of a biological film, all organic matter and mechanical suspensions that have penetrated the pores of the sand loading during the operation of the filter. The washing process should also not disturb the position of the filtering plane.

loading (funneling, etc.) and sequential order of the supporting layers.

If we assume the constant resistance of the passage of water for all points of the lower surface of the filter, then the indicated requirement for uniformity of washing entails the requirement of constant free pressure of the supplied washing water for all of the points indicated in the double bottom of the filter.

The latter requirement illuminates the hydraulics problem in the present conditions and is very complicated, since the flushing water supplied through the pipe has a significant velocity pressure, selects the shortest path of less resistance and punches the load with separate passages, mixing the sand with supporting gravel layers.

Thus, the design of the drainage is set to reduce the velocity head and evenly distribute the wash water under the filter charge.

In separate active structures, these conditions are satisfied as follows. In the drainage of the zero resistance Kommunstro - due to the increased water cushion in the international space; in the drainage of prof. S.V. Moiseev and the trust "Vodokanalizatsi" (on the filters of the southern Leningrad waterworks) - by dividing the flow of wash water into separate streams, horizontal compensation and increasing the "water pillow."

In the proposed design, a jet of wash water flowing out of the supply pipe is pressed against the bottom of the filter with a flat screen and, to facilitate the cancellation of the velocity head, it is divided into separate horizontal layers (belts) with a special step damper. Horizontal compensation is performed as usual in a water patch.

The objective of the proposed design is to create a main jet on horizontal flat layers of tape by applying a stepped damper.

in the form of barriers transverse to the flow direction.

FIG. 1, 3 and 4 of the drawing shows vertical sections of the filters; FIG. 2, 5 and b-horizontal sections of international space.

The step damper can be designed in two systems:

1. According to FIG. 1 and 2, all of the 4 extinguisher bars have a face edge cut off at an angle of due to this, all individual layers are directed into the water pad inclined at the same angle, and the velocity head is lost due to the impact only on the waterbag.

2. According to FIG. 3,4, 5, and 6 bars 4 extinguishers have a cut-off part at an angle of 60 °, partly at an angle of 90. The alternation of these bars creates conditions for the layers to absorb each other (by intersecting the flow lines) before hitting the water layer.

FIG. 1 and 2 represent the drainage design for low and medium throughput filters, with approximately usable area from 3.00 to 12.00 i, with the following symbols adopted; / - square reflective screen; 2 - spacer bolts for mounting the screen above the inlet pipe; 4 - wooden quencher bars; 5 - wooden fillies for the installation of bars. The high throughput filter is depicted in FIG. 3 4, 5 and 6. The design scheme is similar to that described above for a small filter; here / is a reflective box-section screen over the supply pipes, 4 are rectangular quencher wooden bars (boards are placed on an edge) and with a bevel (at an angle of 60) edge, 5-wooden fillies for mounting quencher bars.

If necessary, the damper bars and fillies can be made of metal or concrete.

The subject matter of the invention.

A device for supplying wash water under the drainage of a small resistance of the fast filter, characterized in that

Wash water pipes are installed with cut faces on the angle of the bars 4, in order to quench the velocity head of the wash water and to evenly distribute it under the filter drain by splitting its main jet transverse to the flow direction of the obstacle.

Phi-5

Fig4