DE7900193U1 - MOVABLE ENVIRONMENTAL DEVICE FOR REVITALIZATION BASIN - Google Patents

Description

Applicant; December 28, 1973

Michael Dinnendahl
Höhenberg No. 37
8351 Bernried

Movable circulation device for aeration tanks

The invention relates to a movable Umwälζeinrichtung for activation tanks, with which the tank contents (activated sludge waste water mixture) nuj "in the area of the respective Häumerbrücke standpoint without simultaneous oxygen input directly with a mechanical Umwalzvorricbt-ung (e.g. propeller, pipe pump, etc.) is circulated, which Umwälzvorricntung can be combined with a floor space shield that sweeps over the bottom of the basin and thus a forced mixing of the basin initials and forced evacuation of the activated sludge deposited on the basin bottom in the clearing intervals takes place at the respective scraper standpoint.
Area of application: Aeration basins in biological sewage treatment plants

State of the art:

In the activated sludge tank of biological sewage treatment plants it is important for the cleaning performance of the activated sludge that the sludge is intimately mixed with the discharged wastewater located in the basin. The circulating energy entered must be so large. · ,, that sludge deposits on the bottom of the basin are avoided, as this could cause serious operational disruptions be able.

The circulation is usually combined with the introduction of oxygen, d. H. the process of oxygen entry with surface aerators and with compressed air in the basin, water currents and turbulence are generated that cause the activated sludge to sink Prevent the bottom of the pelvis. For aeration tanks with low loads

this leads to the fact that not only the amount of oxygen required in each case is decisive for the energy expenditure, but also partly the required circulating energy. I. E. the circulating energy is the minimum factor; it will in most cases more oxygen is introduced than the activated sludge needs. Newer systems try among other achieved effects to remedy this maladministration by

a) The ventilation device was designed to be movable and thus not only a small amount of total pool circulation but also zones arise with increased circulation, (e.g. Schreiber Countercurrent pool, Vedewa round pool) or

b) The oxygen input and the circulation have been separated, whereby both systems are designed to be more energy-efficient (e.g. Roto-Flot system from Menzel; oxidation trenches with compressed air ventilation and circulating propellers, Lippeverband Food, etc.)

At the same time, both of the facilities mentioned under a) and b) have the advantage that the oxygen in the air is undersupplied Zones arise, according to more recent findings a basic requirement for the desired denitrification processes, at a) by air intake in the form of a square, at b) by the now possible intermittent ventilation.

Another prerequisite for denitrification processes to run Secondly, however, in the aeration tank there is a concentration of dirt in the areas that are undersupplied with atmospheric oxygen .Zones.

All previously known facilities meet these "two" Basic requirements are not there or are only imperfect inevitably with the classification made under a) and "b" the sown basin contents are circulated and thus zones with increased dirt concentration are not or only insufficiently can form-

The present invention is therefore based on the task of reducing the required energy input and , at the same time, creating the prerequisites required for denitrification processes to run (dirt concentration and insufficient air oxygen supply in the denitrification zone).

Description: System sketch shown in Figure 1

The object is achieved according to the invention in that on a scraper bridge which can be moved over the activation tank (1) (6) one or more mechanical circulation units (7, 8) (e.g. propellers, pumps) are attached, with where the activated sludge - waste water mixture (4) is circulated in the area of the respective bridge position. the Activated sludge (5) deposited on the bottom of the basin (3) during the journey can be carried over with a Basin bottom (3) brushing blade (9) the circulation unit (7, 8) or the Umwälζströmungen forming (10) and again with the remaining tank contents (4) be mixed. The latter can also take place in that the circulating flow generated by the unit (7, 8) (10) is directed against the bottom of the pelvis (3).

The following effects can be achieved simultaneously with the present arrangement:

The circulation is separated from the oxygen input. Effect: The oxygen input can be adjusted exactly according to the oxygen demand be made.

The circulation takes place only at the respective scraper standpoint. Effect: Saving of circulating energy, since not the entire bee content has to be circulated.

A basin with different load areas can be maintained because of the arrangement according to the invention the basin contents are mainly mixed in the vertical direction.

Effect: The desired concentration of dirt occurs in the area of the wastewater discharge, a prerequisite for the denitrification process, since the longitudinal flow in the basin depends on the inflow volume - depending on the basin construction.

The circulation in the denitrification area takes place directly via a mechanical unit.

Effect: In the denitrification zone, the disruptive atmospheric oxygen input can be omitted.

In Figure 1:

1 aeration tank

2 water levels

3 basin sole

4 Activated sludge - waste water mixture

5 settled activated sludge

6 scraper bridge

7 tubular propellers

8 propeller drive

9 Soil sludge clearing shield

10 circulating flow

Claims (2)

■ ♦ »· 1t • -I« ♦ · t 1. Movable circulation device (6, 7, 8, 9) for aeration tanks (1) characterized 7. eichne t that on a via the aeration tank (1) or next to the aeration tank (1) movable device (6) one or more circulation units (7 ₅ 8) for mechanical circulation of the tank contents (4) at each / urgent location the device (6, 7, 8) are installed without simultaneous introduction of oxygen. 2. Movable circulation device (6, 7, 8, 9) for aeration tanks ("I) according to claim 1, characterized in that a floor scraper (9) is also attached that sweeps over the bottom of the pelvis (3).