DE3520217A1 - METHOD AND SYSTEM FOR WATER TREATMENT WITH A FLAKED FLUIDIZED LAYER - Google Patents

Description

Process and system for water treatment with a flake fluidized bed.

The invention relates to a method and a system for water treatment with a flake fluidized bed, in which the flakes are flocculated and separated.

In systems for water treatment with the help of the flake fluidized bed are used to increase performance built inclined walls, which are immersed in the space of the flake fluidized bed and this divide into further rooms. The upper sloping walls of the sections created in this way are provided with deflectors, the lower walls are smooth. The deflectors support the flocculation. The resulting flakes sink to the lower wall and shift downwards, against the current direction. As soon as they reach the lower edge of the wall, they will with the increasing flow of liquid carried upwards. The effect of the clarification is repeated periodically Flow change assisted. With this arrangement, a surface load on the flocculation can be avoided

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Achieve pools of 15 to 20 m.h.

The current systems have the following disadvantages: By installing inclined walls in one Right-angled pools with vertical walls create unused spaces. The subspaces are only partially used for floating, because the mud sinks in the room on the lower wall. The deflectors are attached on one side so that they do not act in the entire volume of the suspension.

The object on which the invention is based is to provide the method and system mentioned at the outset Kind to train so that a better work efficiency can be achieved.

This object is achieved in the method of the type mentioned according to the invention in that the flakes are thickened and enlarged by rotation in water cylinders with a non-whirling flow in concave spaces between the main flow of the liquid, which is brought into a sinusoidally increasing movement, which is caused by the transfer of the movement size of the main flow with the help of wave-shaped walls or baffle plates on flat walls that delimit the flock fluidized bed. The thickening and enlargement of the flakes is carried out in at least two and at most fifteen water cylinders one above the other, with the mean velocity gradient remaining constant or ± n flow direction falling within a range of G = 200 to 20 s. The thickening and enlargement of the flakes is achieved by increasing the bonds between the flakes by addition of a Hilfskoagulierungsmittels and / or by periodically repeating variation of the hydrodynamic forces in the liquid at a frequency of η is 0.01 to 0 ₇ 1 Hz.

In the plant according to the invention, the space of the flaky fluidized bed is formed by a system of verticals Immersion walls in sub-rooms with a wall width of 0/10 to 0.40 m and a length that corresponds to the 4 to 20 times the width, subdivided, with the baffles providing an overflow edge for the mud cut and overlap by 0.05 to 0.30 m. the

Immersion walls are corrugated over the height, preferably sinusoidal or broken or stepped, if necessary they are flat and have a number of deflectors. A section of a period the sinusoidal shape of the baffle is two to six times the width of the sub-space. The rash from the axis of the sine curve is 1/4 to 1/2 the width of the subspace. The deflectors are in Partial space alternately on opposite sides at an angle of 45 * to 70 ° to the horizontal Arranged level and intervene in 1/6 to 1/3 of the width of the sub-space. The distances between the deflectors are 0.5 to 3 times the Width of the subspace.

The method and the plant according to the invention have the following advantages: The space of the flocculent fluidized bed is divided by vertical walls, so that the installation in pools with a right-angled, as well as circular plan is easy. The Sinusfönuige or broken arrangement of the walls or the alternately attached deflectors on flat walls cause a sinusoidal course of the trajectory of the stream. The water cylinders are formed on both sides at concave points on the walls.

The length of a period of the sinusoids or the distance between the deflectors is either the same or it increases in the direction of the flow, which is advantageous in the case of brittle flakes / because the velocity gradient decreases. The dimensions of the individual subspaces are chosen so that the flow is not eddy, ie that the Reynold ³ see number is lower than

ν R

Re = ■ = 600, where ν is the mean progressive Speed, R the hydraulic radius and ν the kinematic viscosity. Some of the flocs escape from the rotating stream and rise into the next water cylinder on where the process repeats itself. Moderate pulsations, for example with a pendulum paddle, which oscillates alternately when entering the area of the flaky fluidized bed, facilitate this

TO agglomeration of the flakes. The diving walls take hold over the overflow edge into the thickening room and divide it into smaller sections. Together with the This will cause pulsations in the sludge level Mud overflow rectified, so that the amount of flakes entrained in the treated water is low.

Exemplary embodiments of the invention are explained in more detail with the aid of drawings. Show it:

Fig, 1a a clarifier with a rectangular plan with the system,

Fig. 1b the same clarifier in longitudinal section, Fig. 1c the same clarifier in cross section,

Fig. 2a a clarifier with a circular plan with the

System,

Fig, 2b the same clarifier in cross section,

3 shows a sinusoidal shaft installation in vertical section,

a shaft installation in the form of stepped bent surfaces in vertical section and

5 shows a level installation with vertical deflectors cut.

As shown in the figures, the raw water with precipitants runs into a clarifier through an inlet 1 into a flocculation space 2 in which paddle-shaped stirring elements 3 are provided. Between the flocculation and clarification space there is a perforated line 4 -Fig. 1- or a gap HFig. 2-. Furthermore, a subchamber 5 of the flock fluidized bed, a baffle 6, deflectors 7 , a sludge overflow edge 8, a channel B for the treated water ^ a drain line 10 for the treated water, a sludge thickening chamber 11 and a desludging line 12 are provided.

The water with ground precipitants flows through line 1 into flocculation room 2. The flocculation is supported by the movement of the pad-shaped stirrer 3, the resulting suspension flows in through the perforated line or through the gap 4 and is with the help of the baffles 6 distributed in the subspaces of the flock fluidized bed 5. In the concave spaces of the wave diving walls and between the deflectors 7, water cylinders rotate, in which the flakes are thickened and enlarged. This process repeats itself in several water cylinders on top of each other. The treated water flows through the channels 9 into the Drain line 10 from. The sludge from the level of the flaky fluidized bed falls over the overflow edge 8 into the thickening space 11 and is periodically

drained through line 12 »

In the plants shown in FIGS. 1 a to 5, a surface load of 15 m: h can be achieved using an iron (III) -containing precipitant , and 20 m: h with the addition of an auxiliary coagulating agent.

The system described can also be used for the separation of water softening and biofloculation resulting particles are used.

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Claims (8)

ν. FONER EBBINGHAUS FINCK PATENTANWÄLTE EUROPEAN PATENT ATTORNE-Y-S MARIAHILFPLATZ 2 & 3, MÖNCHEN 9O POST ADDRESS: POSTFACH 95 O1 6O, D-8OOO MÖNCHEN 95 June 5, 1985 DEAC-32874.5 Vysoke uceni technicke ν Brne Process and system for water treatment with a flake fluidized bed Claims j 1. Process for water treatment with a Flake fluidized bed in which the flakes are flocculated and separated, characterized in that the flakes are rotated in water cylinders with a non-swirling flow in concave spaces between the main flow the fluid is thickened and enlarged, moving in a sinusoidal ascending motion is brought about by transferring the magnitude of motion of the main shape with the help of wave-shaped Walls or baffle plates on flat walls that delimit the flock fluidized bed. 2. The method according to claim 1, characterized in that the thickening and enlargement of flakes at least in two and is carried out in a maximum of fifteen water cylinders one above the other, with the mean velocity gradient kept constant or lowered in the direction of flow in a range of G = 200 to 20 s ~. 3. The method according to claims 1 and 2, characterized gekennzeichne t _/ that an auxiliary coagulant is added to thicken and enlarge the flakes by strengthening the bonds between the flakes and / or the hydrodynamic forces in the liquid at a frequency of η = 0.01 to 0.1 Hz can be changed periodically repetitively. 4. Plant for performing the method according to one of claims 1 to 3, characterized in that g e k e η η draw t that the space of the flake fluidized bed by a system of vertical baffles (6) in sub-rooms (5) with a wall width of 0.10 to 0.40 m and a length that corresponds to the four? up to twenty times the width, divided is, wherein the baffles cut an overflow edge (8) for the sludge and around 0.05 to 0 / 3Om overlap. 5. Plant according to claim 4, characterized in that the baffles (6) over the Height are wavy. 6. Plant according to claim 5, characterized in that the corrugation or sinus is stepped. 7. Plant according to claim 4, characterized in that the baffles (6) are flat and are provided with a number of deflectors (7), 8. Plant according to claim 6, characterized in that g e k e η η draw t that a portion of a period of the sinusoidal shape of the baffle (6) the two to Six times the width of the subspace (5) and the deflection from the axis of the sinusoidal shape 1/4 to 1/2 of the width of the subspace (5) is, 5. Plant according to claim 4, characterized in that the deflectors (7) in the Subspace {5) alternately on opposite sides at an angle of 45 ° to 70 ° to the are arranged in a horizontal plane and intervene in 1/6 to 1/3 of the width of the subspace (5) / the distances between the deflectors (7) being 0.5 to 3 times the width of the partial space (Make 5J.