DE102005048764A1 - Longitudinal grit chamber and grease trap combination for e.g. sewage treatment plant, has flow roll in grit chamber that is connected with grease trap via openings, where grease trap is divided by intermediate wall in separate bowl section - Google Patents

Abstract

The combination has a flow roll (8) in a grit chamber (1) that is connected with a grease trap (2) via openings (4). The grease trap is divided by an intermediate wall (9) in a separate bowl section, where the intermediate wall is arranged over the length of the grease trap. The openings are partially closed with lamellae and extend between the intermediate walls. The openings are arranged such that the dimension of the flow roll in the bowl section can be varied through mechanical input.

Description

The The invention relates to a combined longitudinal sand trap and sand trap in sewage treatment plants, Water purification systems and the like. Although both parts the fulfill different function of sedimentation and flotation form they are a functional unit with mutual influence. In its basic function, each part can be considered separately.

sand trap

at such sand traps becomes a flow roll longitudinal by suitable fluid generated. The rotational speed of the roller is essential here higher than the longitudinal speed the flow of flow, so that the roll flow to determining hydraulic size for sand removal becomes.

There the sand deposition is essentially a function of a flow velocity or a corresponding surface charge can, with this approximate uniform rotation speed the appropriate sand removal can be determined and the Sand trap and the sand trap performance are measured. This method represents a proven solution for the Problem of uniform deposition of sand at uneven, before all with fluctuating flow represents.

The usual fluid are either side venting devices and / or propellers and / or guide devices.

Frequently becomes no even flow roll over the longitudinal extension the sand trap sought or realized, but it is for example an increased at the beginning of the sand trap Air supply and thus a higher Roller speed selected. Due to the uneven roll flow in the Sand trap changed also their influence on the grease capture flow along the Sand trap.

grease trap

This Sand trap is in a unit with a parallel grease trap combined. About openings in the partition between sand and fat catch the fat catch is with the sand trap hydraulically connected and has a substantially identical water level. The openings mentioned are not enough to the water level, to the shooting of the sand trap roller in the To prevent fat catching. The openings are generally with partially closed lamellar elements, so that the flow the sand trap for this reason only to a limited extent in the Sand trap spreads. Across from the highly turbulent flow in the sand trap there is a substantially very calm in the fat catch flow with sometimes very small Flow velocities over which Character is little known. The effect of fat capture is in itself undisputed, but its design according to numerous rules follows mainly empirical guidelines. Because of the unknown flow conditions one can use the fat catcher not measured according to the known rules of flotation. A summary of the hydraulic conditions is not known.

The crosscurrents reach in comparison with the total flow in an individual case and / or locally one considerable size and persist again from differently sized, inward or outward directed Partial flows.

invention

invention task was, the flow to research in the fat catch and to find ways to improve it so that she is uniform and uniform and thus accessible to a design becomes.

The Invention task was solved on the one hand, that by numerical flow simulation it was recognized that in Fat catch overall cross flows, Longitudinal flows and rolling currents on the other hand, that through a subdivision of the fat catch into individual, hydraulically from each other separate basin sections in sections a uniform and generates even flow which is an analysis, an adaptation and a good operation accessible is.

Further advantageous embodiments of the invention are in the claims 2 to 10 called.

in the Fat catch prevail in very different and unexpected cases Partial flows, but in no case a whatsoever, general and uniform flow pattern over the whole extent of the fat catch.

Surprisingly, within the fat trap also significant longitudinal flows in optionally both longitudinal directions and in obvious variety depending on the length and geometry of the system, the size and arrangement of the openings and fins, the size and type of flow and roll flow. In addition, the expected, but their distribution, size and direction of unknown currents (Querströ ments) through the openings. These in turn directly influence the longitudinal flow in the sand trap itself. They sometimes even increase the actual flow in the sand trap. This reduces its separation efficiency. In the circle conclusion to then again the flow in the fat catch is affected.

The Advantages achieved with the concept of the invention lie in the clear hydraulic characteristics of the fat catch and the possibility its design according to the rules of hydraulics. It is too possible, the effect of fat capture later based on the operating results, for example through change the slats a higher or smaller cross flow to reach. This can be beneficial for the individual pelvic sections also happen differently. Another advantage is the fact that in existing installations by simple means, namely by installation of partitions, the concept of the invention can be realized. Most advantageous but that is with the concept of the invention, the fat separation as such essential can be improved because now favorable for the fat separation flow conditions can be achieved in the fat catch.

in the The following will alternate between one or more partitions and Basin sections spoken. Your number in each case appropriate number can be specified or retrofitted be in order to economically achieve the desired hydraulic improvement and fat separation to achieve, namely the flow in the fat catch to improve and optimize.

The Invention is shown schematically in the figure. Show it from the sand and fat catch:

1 : a cross section

2 : a top view.

The sand and fat catch ( 1 ) through the outer walls ( 8th ) and the inclined floor ( 15 ) educated. The liquid has an open water level ( 6 ) on. In the sand trap ( 1 ) the flow roll ( 8th ) in this case by blown air from an air line ( 7 ) generated. In this case, transported in a known manner, the rising air, the liquid with upwards. For continuity reasons and favored by the shape of the pelvic cross-section, the liquid in said flow roll ( 8th ) in the upper area to the other side of the pool, there again down and back to the exit area. According to the invention, the rotational speed of the roller is substantially higher than its longitudinal speed. The rotational speed is therefore the decisive for the action of sand deposition speed.

The air line ( 7 ) can be of uniform diameter or, as in 1 shown from line sections ( 7.1 . 7.2 . 7.3 ) with different diameters and / or sections with different drilling plans, which is not shown here. At the sand trap end, the air duct and ventilation may be omitted. With these measures, sections of different aeration and thus in the associated pelvic sections ( 13 ) a different thickness of the flow roll ( 8th ), so that, for example, the sand trap end down a lower circulation prevails and already settled sand is not entrained again.

The adjacent fat catch ( 2 ) is supported by outer walls ( 14 ), the partition ( 3 ) and the inclined floor ( 15 ) educated. It is separated by one or more partitions ( 9 ) into two or more basin sections ( 12 ), which are completely separated hydraulically. The pelvic sections ( 12 ) are above the openings ( 4 ) in the partition ( 3 ) hydraulically with the sand trap ( 1 ) in connection. The openings ( 4 ) are well below the liquid level ( 6 ) and with lamellae ( 5 ) partially closed. The openings ( 4 ) should on the one hand as large as possible sand and fat trap connect to each other, on the other hand, the cross-flow ( 10 ) limit. That's why the opening ( 4 ) partially closed with lamellae, which the free cross-section of the opening ( 4 ) reduce evenly.

If the partitions ( 9 ) and thus the pelvic sections ( 12 ) in bold ( 2 ) approximately according to the pelvic sections ( 13 ) in the sand trap ( 1 ) are placed in the pelvic sections ( 12 ) each have their own flow conditions. In addition, the direct flow exchange between the individual basin sections ( 12 ), so that in the pelvic sections ( 12 ) can express a roll flow. Even with a different arrangement of the intermediate walls ( 9 ) will appear in the pelvic sections ( 12 ) each set its own flow, usually in the form of a roller flow. This roll flow in the single basin section ( 12 ) is in each case characteristic of the flow roll ( 8th ) in the associated basin section ( 13 ).

In accordance with the rules, the separated fat accumulates in the pelvic sections ( 12 ) at the water level ( 6 ). The fat is removed from there, for example by skimming or clearing. For this purpose, a not shown here, longitudinally movable clearing device used who the. Preferably, the fat can be pushed to the front side of the sand and fat trap and removed there with a dozer blade. For this purpose, the upper part of the partition ( 9 ) preferably hinged, namely, for example, as a flap ( 16 ), be formed. The flap may preferably also consist in a simple form of a total of an elastic part, which with the upper part of the partition ( 9 ) connected is.

The flap or flaps ( 16 ) are deflected by the passing clearing device and automatically brought back into their closed position either by their elastic return or by a separate return device. The clearing device thus moves over all pelvic sections in a single operation ( 12 ) away.

Since the aim of the invention is to create defined and uniform flow conditions in the fat catch, it is considered to be particularly advantageous if the openings ( 4 ) over the entire length (L) between two partitions ( 9 ) of the respective section ( 12 ) of the fat catch ( 2 ). This is not shown in the picture. Rather, the figure shows a commonly chosen formation of the opening ( 4 ) in the partition ( 3 ). The result is in the corner between partition ( 3 ) and intermediate wall ( 9 ) Flow vortices, which the uniform flow through the opening ( 4 ) to disturb. The degree of the disturbance is understandably dependent on the dimensions and the size of the cross flow and therefore plays a larger or smaller role in individual cases.

1

sand trap

2

grease trap

3

partition wall

4

Opening (in the partition)

5

slats

6

water level

7

air line

8th

flow roller (in the sand trap)

9

partition

10

crossflow

11

Flow flow (in Sand trap)

12

Beck section (in bold)

13

Beck section (in the sand trap)

14

exterior walls

15

ground

L

Length (of Basin section in the fat catch)

Claims (10)

Longitudinal sand trap ( 1 ) and fat catch ( 2 ) with a longitudinal flow roll ( 8th ) in the sand trap ( 1 ) in the direction of the flow ( 11 ) in sewage treatment plants, water purification plants and the like, formed from a channel-like, longitudinally-traversed sand trap ( 1 ) and a parallel, with the sand trap ( 1 ) via openings ( 4 ) associated fat catch ( 2 ), wherein the flow roll ( 8th ) in the sand trap ( 1 ) by suitable fluid ( 7 ), characterized in that the fat catcher ( 2 ) by one or more, over the length of the fat trap ( 2 ) distributed partitions ( 9 ) into several separate basin sections ( 12 ) is divided. Longitudinal sand trap and grease trap according to claim 1, characterized in that the openings ( 4 ) in a conventional manner with fins ( 5 ) are partially closed. Longitudinal sand trap and grease trap according to claims 1 and 2, characterized in that the openings ( 4 ) over the entire length (L) between two partitions ( 9 ) of the respective section ( 12 ) of the fat catch ( 2 ). Longitudinal sand trap and grease trap according to claim 1 to 3, characterized in that the intermediate walls ( 9 ) are preferably arranged where the size of the flow roll ( 8th ) in the associated basin section ( 13 ) changes by mechanical specifications. Longitudinal sand trap and grease trap according to claim 4 for a sand trap ( 1 ) with pelvic sections ( 13 ), in which the ventilation performance of the aerators ( 7 ) and thus the flow roll are different, characterized in that the position of the intermediate walls ( 9 ) and thus the pelvic sections ( 12 ) analogous to the pelvic sections ( 13 ) to be ordered. Longitudinal sand trap and grease trap according to claim 5 for a sand trap ( 1 ) with pelvic sections ( 13 ), in which the ventilation performance of the aerators ( 7 ) and thus the flow roll are different, and wherein the basin sections ( 12 ) analogous to the pelvic sections ( 13 ), characterized in that to the individual basin sections ( 13 ) two or more basin sections ( 12 ) to be ordered. Longitudinal sand trap and fat catch according to claim 1 to 3, characterized in that the pelvic sections ( 12 ) are arranged approximately uniformly over the length of the sand and fat trap. Longitudinal sand trap and grease trap according to one of claims 1 to 7, characterized in that the uppermost part of the intermediate walls ( 9 ) as a flap ( 16 ) is trained. Longitudinal sand trap and grease trap according to claim 8, characterized in that the flap ( 16 ) at least partially made of an elastic material be stands. Longitudinal sand trap and grease trap according to one of claims 1 to 9, characterized in that the intermediate walls ( 9 ) flush with the adjacent walls (partition ( 3 ), Ground ( 15 ) and outer wall ( 14 )) and connect the pelvic sections ( 12 ) completely separate hydraulically.