DE10210511B4 - Method and device for treating a sludge, in particular a sewage sludge - Google Patents

Abstract

Process for treating a sludge, in particular a sewage sludge or industrial sludge, in which
a) at least one active ingredient (P) and at least one solvent (FH) is added to at least one treatment tank and is processed into a drug solution and
b) the at least one treatment tank (34) is taken off during at least one treatment period drug solution and the sludge is fed,
in which
c) in which at least one preparation container a circulation of the active substance solution and the not yet dissolved active substance (s) and solvent is generated, which successively flows through a first zone (Z1) and a second zone (Z2) of the preparation container,
d) the active ingredient solution and the not yet dissolved active ingredient (s) and solvent in the first zone of at least one mixing tool (37), preferably under application of shear forces and / or high mixing energy input, mixed or mixed.

Description

The The invention relates to a method and a device for treating a sludge, in particular a sewage sludge or industrial sludge.

To the Drain of clarification or industrial sludges as part of the purification of waste water a method is known in which the sludge through a filter system guided which is the liquid portion consisting essentially of water lets through the mud and filter out the solids from the mud. The mud Add a drug solution with polymers before filtering, about the degree of drainage or to increase the degree of drying of the dry sludge, ie to drain the mud better. The mode of action of the drug solution can one can imagine that the polymers are the solid particles in the mud bind together by electrical charge and as a result, caused electrical attractions and thereby support or improve their separation from the water. The filtered out dehydrated dry sludge mass is often referred to as a filter cake. Improve the polymers also the passage of the water through the filter cake at the following Quantities of sludge.

For the preparation of the drug solution, a two-tank system with a maturation tank and a storage tank with a tank volume of between 3 m ³ and 10 m ^{3 is known} depending on the manufacturer or the desired capacity. The active substance solution is first prepared in the ripening tank from a liquid or pulverulent polymer substance to be dissolved and water as solvent. The polymer substance and the water are mixed in the ripening tank by constant stirring until, after a ripening time (or: batching time, processing time) of typically about one hour (1 hour), the active ingredient solution can be used to dewater a sludge. After maturation, the processed Wirkstofflö solution is transferred to the storage tank, there also constantly stirred and then taken continuously during the filtering or dewatering process the storage tank and fed to the sludge until the storage tank is empty. Following this, the active ingredient solution, newly prepared in the meantime in the maturation tank, is pumped into the empty reservoir tank and re-added to the sludge in a new dewatering process. Because of the high filling volumes of the two tanks and the long maturation time, waiting time, transfer time and discharge time, the active substance solution remains in the known processes many hours, sometimes even several days in the tanks, until it is added to the mud. However, according to legal regulations, the active ingredients in the water must be broken down in order not to pollute the waters. The half-life at which half of the active ingredients are broken down is typically in the range of a few hours.

This now has the consequence that the effectiveness of those in the tanks drug solution towards the end of the maturing process and at the beginning of the filtering process reaches a maximum value and then through during the filtering process the degradation of drug concentration increasingly decreases to one Final value of typically only at most about 50% to 60% the initial one maximum effectiveness. Therefore, during a filtering process either more and more active ingredient solution is added to the passing amount of sludge to compensate for the decreasing drug concentration, or, for the same amount of drug solution, a reduced effectiveness be accepted.

From the DE 198 08 156 A1 a device for conditioning conditioner for aqueous sludge is known with a dissolving chamber to which are supplied from a stock solution pump funded drug stock solution and under pressure inflowing additional water, a dissolving chamber downstream mixing chamber in which a rotating distributor head for mixing in the Dissolution chamber formed mixture of active ingredient stock solution and make-up water is arranged, and with a mixing chamber downstream buffer memory, which is connected via a metering pump with a seed device which emits the mixed in the mixing chamber drug solution as a conditioning agent to the flowing in a delivery pipe aqueous sludge. The distribution head has distributed about its axis of rotation substantially parallel to the axis of rotation extending longitudinal slots as fluid outlets for the approach of the dissolving chamber mixture and radially outward, and along the axis of rotation extending mixing vanes. The mixture then flows through the slit-shaped fluid outlets to the outside in the mixing chamber and is mixed there by the mixing blades. The speed of the distributor head is operated in a range between 700 rpm (revolutions per minute) and 2,500 rpm. The mixture of active ingredient stock solution and make-up water introduced from the dissolving chamber is guided from below into a shaft of the distributor head, then exits through the slots and, after being mixed by the mixing blades, is led out of the mixing chamber again directly through a lateral outlet.

Thus, the drug solution flows through at the DE 198 08 156 A1 Known device, the mixing chamber with the distributor head as a mixing tool only a single time and then immediately fed to the mud.

The treatment of the conditioner runs according to the statements of DE 198 08 156 A1 practically continuously. The mixture swells in the mixing chamber and the device transfers the solution into the aqueous slurry without a separate ripening time. The amount of additional water needed is lower. The mixing blades of the distributor head move only a short distance from the wall of the mixing chamber, which is advantageous for the mixing effect. On the production line for the aqueous sludge, a conditioning measuring device is arranged, which measures the conditioning state of the aqueous sludge and controls the stock solution pump via a computer. It can be kept constant per unit of time supplied amount of make-up water. Since the amount of conditioning agent produced per unit time does not always coincide with the amount of conditioning agent removed per unit time from the metering pump, these different amounts are balanced by the buffer storage in which the conditioning agent can also continue to swell.

From DE 198 08 156 A1 known device is designed for a liquid drug stock solution for mixing with water as a solvent. When using a powdered drug would be with the from the DE 198 08 156 A1 known device not sufficient mixing and solution of the solid drug substance in the water and thus also no sufficient effectiveness of the drug solution achievable.

Of the The invention is based on the object, at least a part to reduce the problems mentioned in the prior art or to avoid.

These Task is according to the invention solved by a method according to claim 1 or by a device according to claim 36.

• a) Zudosieren wenigstens eines Wirkstoffs (oder: einer Wirksubstanz) und wenigstens eines Lösungsmittels in wenigstens einem Aufbereitungsbehälter und Aufbereiten zu einer Wirkstofflösung während eines Aufbereitungszeitraumes;
• b) Entnehmen der Wirkstofflösung aus dem Aufbereitungsbehälter und Zuführen zu dem Schlamm in einem Behandlungszeitraum;
• c) Erzeugen einer Zirkulation der Wirkstofflösung und des oder der noch nicht gelösten Wirkstoff(s/e) und Lösungsmittel in dem Aufbereitungsbehälter während des Aufbereitungszeitraumes, wobei die zirkulierende Strömung fortlaufend nacheinander eine erste Zone und eine zweite Zone des Aufbereitungsbehälters durchströmt;
• d) Vermischen der Wirkstofflösung und des oder der noch nicht gelösten Wirkstoff(s/e) und Lösungsmittel in der ersten Zone mittels wenigstens eines Mischwerkzeuges, vorzugsweise unter Beaufschlagung mit Scherkräften und/oder unter Eintrag einer hohen Mischenergie, im Allgemeinen während des Aufbereitungszeitraumes.

The process according to claim 1 for treating a sludge, in particular a sewage sludge or industrial sludge, comprises the following process steps:

• a) dosing at least one active ingredient (or: an active substance) and at least one solvent in at least one treatment container and processing to a drug solution during a treatment period;
• b) removing the drug solution from the treatment vessel and feeding it to the mud in a treatment period;
• c) generating a circulation of the active ingredient solution and the undissolved active ingredient (s) and solvent in the treatment tank during the treatment period, wherein the circulating flow successively flows through a first zone and a second zone of the treatment tank;
• d) mixing the active ingredient solution and the undissolved active ingredient (s) and solvent in the first zone by means of at least one mixing tool, preferably by applying shear forces and / or by introducing a high mixing energy, generally during the treatment period.

• a) wenigstens einen Aufbereitungsbehälter zum Aufbereiten von Wirkstofflösung aus wenigstens einem Wirkstoff und wenigstens einem Lösemittel,
• b) wenigstens eine Zudosiereinrichtung zum Zudosieren des oder der Wirkstoff(s/e) und der oder des Lösemittel (s) in dem Aufbereitungsbehälter,
• c) wenigstens eine Zuführeinrichtung zum Entnehmen von Wirkstofflösung aus dem Aufbereitungsbehälter und Zuführen dieser Wirkstofflösung zu dem Schlamm,
• d) wenigstens eine Mischeinrichtung zum Mischen des oder der im Aufbereitungsbehälter befindlichen Wirkstoff(s/e) mit dem oder den Lösungsmittel(n), wobei die Mischeinrichtung
• d1) ein innerhalb einer ersten Zone des Aufbereitungsbehälters angeordnetes Mischwerkzeug und
• d2) in Förderwerkzeug in einer von der ersten Zone getrennten zweiten Zone des Aufbereitungsbehälters zur Erzeugung einer Zirkulation der Mischung im Aufbereitungsbehälter durch die erste Zone und die zweite Zone umfasst.

The apparatus according to claim 36 for treating a sludge, in particular a sewage sludge or industrial sludge, is preferably provided for carrying out a method according to the invention and comprises

• a) at least one preparation container for preparing a solution of active substance from at least one active substance and at least one solvent,
• b) at least one metering device for metering in the active substance (s) and the solvent (s) in the treatment container,
• c) at least one feed device for taking off active ingredient solution from the preparation container and feeding this active substance solution to the sludge,
• d) at least one mixing device for mixing the or in the treatment container located drug (s / e) with the solvent or solvents, wherein the mixing device
• d1) a mixing tool arranged within a first zone of the treatment tank and
• d2) in the delivery tool in a separate from the first zone of the second treatment zone of the container for generating a circulation of the mixture in the treatment tank through the first zone and the second zone.

The Circulation of the drug solution according to the invention As a result, the suspension or mixture of active ingredient and solvent passes through the first zone several times with the mixing tool and a particularly good mixing and almost complete resolution of Active substance (s) is achieved in the at least one solvent. This allows a very short reprocessing time, so that the processing "on-line" or "just-in-time" during the Treatment time can be done. This is with the present method and the present device for the first time for solid or powdered drugs possible.

Under a sludge is understood in the present application, a flowable mixture of solid particles and liquid. The solids Particles are generally suspended in the liquid and typically have a relatively high weight fraction by weight, so that in general the slurry has a higher viscosity than the liquid.

advantageous Embodiments and developments of the method and the device according to the invention emerge from the other, dependent claims 1 and 36 respectively dependent claims.

• – Halten oder Einstellen der Wirksamkeit der dem Schlamm zugeführten Wirkstofflösung während des gesamten Behandlungszeitraumes zwischen einer maximalen Wirksamkeit und einer nicht mehr als 30 % unterhalb der maximalen Wirksamkeit liegenden minimalen Wirksamkeit.

In general, the effectiveness of the prepared drug solution, for example, by law, decreases the active substance concentration of the drug solution continuously from. Therefore, the further process step is preferably provided:

• Maintaining or adjusting the effectiveness of the sludge-fed drug solution throughout the treatment period between maximum efficacy and minimal efficacy no greater than 30% below maximum efficacy.

These embodiment the invention is based on the consideration, the effectiveness of the drug solution while the treatment of the sludge consistently above seventy percent (70%) of maximum efficacy. Through this control or regulating the effectiveness of the drug solution will be the amount consumed of active ingredients the method known from the prior art significantly reduced.

• – Halten oder Einstellen der im Aufbereitungsbehälter befindlichen Menge, insbesondere des Volumens oder auch der Masse, der Wirkstofflösung und der noch nicht gelösten Mischung aus Wirkstoff(en) und Lösemittel(n) zwischen einer Maximalmenge und einer Minimalmenge, die größer ist als die Hälfte der Maximalmenge.

In a particularly advantageous embodiment, the method comprises the further method step:

• Holding or adjusting the amount present in the preparation container, in particular the volume or mass, of the active ingredient solution and the not yet dissolved mixture of active ingredient (s) and solvent (s) between a maximum amount and a minimum amount which is greater than half of maximum amount.

The Device accordingly preferably comprises a control or Control device for controlling or regulating the processing container located in the Amount of drug solution between a maximum amount and a minimum amount that is larger as at least half the maximum amount.

By the control or regulation of the processing tank Quantity (the drug solution and suspension or mixture of the undissolved constituents) in between The maximum amount and the minimum amount lying area is the the treatment tank for the treatment of the sludge taken drug solution continuously or in individual steps repeatedly refilled and reconditioned. Furthermore can in comparison to the prior art, relatively small mixing tanks or Reprocessing tank used be, because the drug solution demand-compensated, is produced and stored no residue in a storage tank must become.

• a) in aufeinanderfolgenden Aufbereitungszyklen neue Wirkstofflösung im Aufbereitungsbehälter aufbereitet, wobei
• b) jeder Aufbereitungszyklus bei Erreichen oder Unterschreiten der Minimalmenge im Aufbereitungsbehälter gestartet wird,
• c) in jedem Aufbereitungszyklus
• c1) während einer Zudosierphase Wirkstoffe und Lösemittel dem Aufbereitungsbehälter zudosiert wird, wobei der Zudosier-Mengenstrom zumindest im zeitlichen Mittel größer ist als der Entnahme-Mengenstrom der Wirkstofflösung, solange, bis die Maximalmenge erreicht ist, und dann die Zudosierung wieder beendet wird, und
• c2) während einer Abnehmphase infolge der Entnahme an Wirkstofflösung die Menge im Aufbereitungsbehälter abnimmt, bis wieder die Minimalmenge erreicht wird.

The preparation of the drug solution is done in a particularly advantageous embodiment with generally continuous withdrawal of drug solution by intermittent addition. In particular, will

• a) processed in successive reprocessing cycles new drug solution in the treatment tank, wherein
• b) each preparation cycle is started when the minimum quantity in the preparation tank is reached or fallen below,
• c) in each preparation cycle
• c1) during a Zudosierphase agents and solvent is added to the preparation tank, the Zudosier flow rate is greater than the withdrawal rate of the drug solution at least on average over time, until the maximum amount is reached, and then the metering is terminated again, and
• c2) during a removal phase as a result of the removal of active substance solution, the amount in the preparation container decreases until the minimum quantity is reached again.

The flow rates (Flow rates or mass flows), So the amount per time, during dosing and removal are preferred each substantially constant in time, so that a linear Course results.

The Preparation times or cycle times of each treatment cycle are generally much smaller than in the prior art and generally range between 1 minute and 10 Minutes, especially between 2 minutes and 8 minutes and preferably between 3 minutes and 6 minutes, and / or are smaller than that Treatment period, in particular by at least a factor of 20 and preferably at least a factor of 100.

The special 2-point control method with the intermittent addition now allows in a particularly advantageous development, the calculation of the removed during the treatment period or a sub-period of the treatment period amount of drug solution or their flow without a meter in the extraction line and / or the Zudosiermengenstromes the metered drug Solvent mixture or, in the case of a known or at any time known genverhältnis of active ingredient and solvent, the flow rate of the solvent during dosing without a meter in the metering for the solvent, such as a water meter. The respective flow rates are equal in a dense system and negligible losses because of the continuity equation, so that the cycle times of the treatment cycles or the periods of their dosing or Abspritzphasen or the temporal integrals or the sums of the treatment cycles in the treatment vessel changing amounts a direct Measure of the inflowing or withdrawn quantities.

With the thus determined removal flow rate during the treatment period or a sub-period of the treatment period by means of a conveyor, in particular a delivery pump, removed drug solution can even in a particular embodiment the current delivery characteristic or delivery rate the conveyor be determined, in particular by comparison with a speed a drive of the conveyor.

The liquid the sludge consists in most cases at least predominantly of water.

The Sludge treatment is preferably a separation of the solid in the mud of the liquid, especially drainage an aqueous one Sludge. This drying of the sludge is preferably by means of a filter performed.

The Method and apparatus according to the invention are for treatment different sludges suitable. So can in addition to sewage sludge, the when treating wastewater in sewage treatment plants, industrial sludge is also treated be involved in industrial processes and promotion of raw materials. In particular, here are without limitation the Generality as industrial sludge in the paper or cellulose industry accumulating cellulose slurries, im Ore mining accumulating ore-containing sludge or in oil production resulting oily or oil and salt water containing sludges called, in which a separation of the solid particles from the liquid with support the active polymers is required.

The solvent for the drug solution is generally water, the active ingredients are generally polymers or polyelectrolytes for improving drying or dehydration of the mud.

The Filtrate water obtained may be in an environmentally friendly embodiment as a solvent for the treatment the drug solution used and thus recovered become

The Method and apparatus are preferably for any Admixture of liquid active ingredient and / or solid active ingredient in any ratio to the solvent designed. The metering device contains a solvent feed system for this purpose for feeding of solvents, a liquid drug delivery system and a powder feeder for metering active ingredient powder. Preferably is first the liquid agent the solvent can be added or added to this and then the active ingredient powder the mixture of solvent and liquid agent or, if no liquid agent was added, the pure solvent attached.

In an advantageous embodiment the metering device comprises a mixing pot connected to the solvent feed system or vortex pot and the powder feeder is above the vortex pot for feeding of drug powder in the vortex pot and flowing solvent therein arranged. In a preferred embodiment is by a fan or the like Means an air flow is generated, which the active ingredient powder on a Deflector deflects and thereby homogenized the active ingredient powder. The Active ingredient powder is then transferred from the baffle plate into the vortex pot guided or dropped.

The Invention will continue in the following with reference to exemplary embodiments and explained in more detail. there Reference will be made to the drawings. Each show in one schematic representation:

1 A first embodiment of a device for treating a sludge in an overall diagram,

2 A second embodiment of a device for treating a sludge in an overall diagram,

3 a treatment container with mixing device arranged therein in a schematic interior view,

4 a cross section through the mixing device of 3 along the in 3 sectional plane designated IV-IV,

5 a diagram of the time course of the processing container in the amount of the active ingredient and the effectiveness of the drug solution, and

6 a in 5 with a circle enlarged section of the time course of Wirk substance solution and the effectiveness of the drug solution for two treatment cycles.

Corresponding parts and sizes are in the 1 to 6 provided with the same reference numerals.

In the 1 and 2 are two different embodiments each of a device for treating an aqueous sludge, for example sewage sludge or industrial sludge, in a conveyor pipe, of which a pipe section 1 shown is shown. The mud flows in the direction of an arrow 2 to a filter, not shown, where it is dehydrated or dried. In the pipe section 1 is a vaccine device 3 effective in the pipe section 1 a distributor head 4 and outside the pipe section 1 a drive 5 having. The distributor head of the feeding device for feeding the active substance solution L to the sludge can in particular according to DE 100 40 546 A1 be constructed with mixing blades and arranged axially of the axis of rotation slots from which the drug solution L emerges and then into the mud in the pipe section 1 is mixed in at high speeds.

In the direction of the arrow 2 after the vaccination device 3 , ie downstream, is on the pipe section 1 a measuring device 6 connected, the conditioning condition, in particular the flocculation and / or Filtratbeschaffenheit measures, and with a control unit 7 connected, in turn, with a solution pump 8th is in operative connection and controls them. The solution pump 8th is in a supply line 9 arranged to the inoculating device 3 leads and in which also a check valve 10 is arranged. Further, the solution pump 8th with its vacuum side with an outlet 52 a treatment tank 34 connected.

The solution pump 8th forms together with the vaccine device 3 and the supply line 9 with the shut-off valve 10 a supply means for supplying drug solution L from a treatment tank 34 to the mud in the production pipe 1 ,

In the processing tank 34 protrudes vertically from above down an inlet pipe piece 33 whose end or mouth area immediately before a trained as a propeller or impeller conveying tool 35 is arranged. Below the conveying tool 35 is inside a laterally closed mixing chamber 36 whose interior is a first zone Z1 of the treatment tank 34 makes, a mixing tool 37 arranged having two or more laterally projecting mixing blades and about a vertical axis of rotation A together with the conveying tool 35 is rotatable.

The rotational speeds or speeds of a common drive 38 powered, coupled tools 35 . 37 are thus the same in the illustrated embodiment. By a reduction or separate drives but also different rotational speeds for the conveying tool 35 and the mixing tool 37 will be realized. The speeds for the mixing tool 37 and the conveying tool 35 are typically set at between about 700 rpm (rpm) and 1,800 rpm, preferably in a range between 1,200 rpm and 1,700 rpm, typically 1,500 rpm.

Through the inlet pipe piece 33 becomes one in a vortex pot 21 produced or metered mixture FH + P from a solution FH and an active ingredient powder P the propeller of the conveying tool 35 fed. By the rotation of the propeller blades of the conveying tool 35 the mixture becomes FH + P from the inlet pipe section 33 sucked and substantially axially to the axis of rotation A in the mixing chamber 36 and thus into the first zone Z1 of the treatment tank 34 promoted.

In the lower part of the mixing chamber 36 are lateral outlet openings 50 and 51 provided by the the mixing tool 37 mixed mixture FH + P back into the area outside the mixing chamber 36 of the treatment tank 34 , which is referred to as second zone Z2, led out.

Due to the suction effect of the conveying tool 35 a large part of the mixture in the second zone Z2 is conveyed back up and passes through the mixing chamber 36 one more time. There is thus a circulation or swirling flow in the liquid mixture FH + P within the treatment tank 34 generated, which successively passes through the two zones Z1 and Z2 and thus leads to a repeated mixing of the two components FH and P of the mixture FH + P and accelerates the dissolution of the powder P in the solution FH and supported. The finished active substance solution L, which is produced in practice by complete dissolution of the powder P in the solution FH, is supplied by the solution pump 8th over the outlet 52 of the treatment tank 34 aspirated.

Above the vortex pot 21 is a powder feeder 31 , For example, a multi-chamber feeder, arranged, the precisely metered amounts of powder of active ingredient powder P from a powder supply 29 in a storage container in the vortex pot 21 added. At the powder supply 29 is a sensor 32 to monitor a required minimum of active ingredient powder in the supply 29 arranged.

The solution FH is from a dissolving chamber 20 the vertebrate pot 21 fed. The vortex pot 21 has a conically downwardly tapered mixing surface over which a film of solution FH spirals down E into the inlet pipe section 33 flows. On this film of the solution FH, the active ingredient powder P is scattered.

For a finer distribution of the active ingredient powder P in the solution FH an unillustrated air flow can be used, which is against a baffle plate, not shown above the vortex pot 21 is directed, from which the drug powder P rebounds and into the vortex pot 21 falling. This reduces the agglomeration of powder particles of the active ingredient powder P and leads to a greater homogeneity of the distribution of the powder particles of the active ingredient powder P in the solution FH in the vertebrate well 21 , In particular, the air flow can be simply from the cooling fan of a drive motor for the powder feeder 31 be diverted.

The dissolution chamber 20 are used as starting materials for generating the solution FH from a liquid agent delivery system 82 a Flüssigwirkstofflösung F and a water supply system 12 Water H supplied as a solvent. The liquid drug delivery system 82 for the liquid active substance F comprises a series connection of a metering pump 26 a stopcock 25 , another stopcock 24 and a liquid drug supply 23 , seen against the flow direction. The liquid active substance F is a known liquid polymer active ingredient in which polymers are dissolved in a solvent, in particular a carrier oil.

The water supply system 12 for feeding the water H into the dissolving chamber 20 includes a series circuit, seen in the flow direction, from a supply 11 or, alternatively, a connection to a water pipe, a stopcock 13 , a dirt filter 14 , a pressure regulator 15 with pressure gauge 16 , a water valve 17 , a water meter 18 and a check valve 19 , The concentration of the liquid agent F in the solution FH may be in the dissolving chamber 20 and changed by controlling the respective delivery systems. In particular, the solution FH can also consist only of pure water H if no liquid component F is supplied.

The feed system for the water H, the liquid agent F and the solution FH formed therefrom and the fluidized bed 21 with the powder feeder 31 can be summarized as Zudosiereinrichtung for metering active ingredient powder P and / or active ingredient stock solution F and solvent H.

In the embodiment according to 2 is different from the embodiment according to 1 the water supply system 12 simplified and includes for supplying the water H only a connection to a water pressure line of typically 4 to 6 bar, a stopcock 13 and a water valve 17 with blocking function. So it's in the water supply system 12 according to 2 neither pressure gauges nor water meters available. Nevertheless, in the system according to the invention, a quantity detection of the water H is possible, which will be explained.

The water H is now according to 2 at a mixing point 83 mixed with the liquid agent F, that of a Flüssigwirkstoffzuführsystem 82 that like in 1 is constructed, is supplied. A dissolution chamber 20 is in 2 not available anymore. The mixing of water H and liquid active substance F is sufficiently good, even without a dissolving chamber, and the water pressure of the water line is also sufficient, without additional pump, the mixture or solution FH to the fluidized-bed 21 to transport.

Since the mixing of liquid substance F with water H is much easier than with active ingredient powder P, it makes sense first, as in 1 and 2 to mix the liquid active substance F with the water H and then first to supply the active ingredient powder P. In principle, however, a reverse order is conceivable.

There the ones available on the market Polymer blends specific for Ingredients of the mud are composed and different good in powder or liquid Act shape is with the variable metering device according to the invention a virtually arbitrary combination of liquid polymers and powder polymers for the drug solution L possible. So it can be in a simultaneous operation a liquid-powder-mix function ever according to filtration needs be parameterized, by a corresponding design of the controller in a control facility, which is generally one or more Microprocessors and memory with appropriately stored software or control algorithms. The relationship the proportions of water H and polymer FH and / or P in the finished drug solution is generally included between 1: 150 and 1:80 1: 100.

2 also shows something more clearly than 1 through the conveying tool 35 produced circulation of the mixture FH + P and the drug solution L generated therefrom within the treatment tank 34 through zones Z1 and Z2.

It is also in 1 and 2 to recognize that the conveying tool 35 on the one hand conveys a major part or the major part of the circulating mixture into the zone Z1, but also a smaller part outside the mixing chamber 36 circulated in the outer zone Z2. The revolution in Zone Z2 also serves to prevent the settling of still undissolved polymers on the container wall of the treatment tank 34 , From the inlet pipe piece 33 Exuding mixture FH + P is almost completely from the propeller of the conveying tool 35 brought into the zone Z1, in which the mixing tool 37 ensures a strong mixing. The conveying tool 35 thus generates in the embodiments according to 1 and 2 In addition, a very turbulent soil and surface longitudinal flow in the filled treatment tank 34 with which not only the active substance product is optimally dissolved, but also no deposition of the highly viscous polymer solution on the inner walls of the treatment tank 34 can be done.

In the treatment tank 34 are now a topmost level sensor 39 for detecting a maximum filling amount M _max , an underlying second level sensor 40 arranged to detect a minimum degree of filling or a minimum filling amount M _min , wherein both level sensors 39 and 40 clearly above the conveying tool 35 are arranged. Further, a third level sensor 41 below or at the level of the conveying tool 35 provided that signals a too low degree of filling when the treatment tank 34 is "empty", so to speak.

With the level sensors 39 and 40 such as 41 is a not shown, preferably integrated in the aforementioned control device, control and / or regulating device connected to the measurement signals of the level sensors 39 and 40 for a control of the filling level, filling volume or generally the amount M of in the treatment tank 34 existing mixture FH + P and already dissolved drug solution L used.

The control device is furthermore connected to the metering device, in particular to the powder metering device 30 and the delivery system for the solution FH, in particular the water supply system 12 , there in particular the stopcock 13 , as well as the feeding system 82 for the liquid active substance F, in particular its stopcocks 24 and or 25 and the feed pump 26 , By placing the metering device and thus the metered mixture FH + P is now the amount M in the treatment tank 34 always kept in the control interval between the maximum amount M _max and M _min .

The operating volume or maximum filling volume corresponding to the maximum amount M _max is typically 100 l (liters) to 300 l, preferably 150 l to 190 l. The respective amount M _max - M _min to be replenished is typically 10 l to 30 l, in particular 15 to 25 l and preferably 20 l. The ratio M _min / M _max is generally in a range between 0.7 and 1, in particular between 0.8 and 1, advantageously between 0.85 and 1 and preferably between 0.9 and 1.

By regulating the filling quantity M in the treatment tank 34 by means of quantity sensors or level sensors 39 and 40 and the control and regulating device, not shown, a two-point control loop is realized, the control behavior in the diagram according to 5 and 6 is shown.

At regular time intervals Δt of typically 2 to 8 minutes, conditioning cycles are performed. In each cycle, after reaching the minimum amount M _min , detected by the lower level sensor 40 , the amount M in the processing tank 34 increased by adding or refilling the mixture FH + P with a sufficiently large volume flow, until the maximum amount M _max , detected by the upper level sensor 39 is reached. The metering phase is now complete. Due to the continuous extraction at the outlet 52 reduces the amount M of the drug solution L in the treatment tank 34 during a subsequent weight loss phase again until the minimum amount M _{min is} reached again and the cycle begins. As in 5 it can be seen, for example, 20 such cycles take place in one hour.

The cycle time .DELTA.t and the replenishment amount M _max -M _min are dependent on the need for a specific sludge treatment process removal flow rate (withdrawn amount per unit time) of the drug solution L. However, the cycle time .DELTA.t should not fall below a minimum cycle time to a sufficient mixing and effectiveness W of To ensure active ingredient solution L.

The mixing device with the conveying tool 35 in the mixing tool 37 as well as the drive 38 remains active during the entire control and treatment phase, so that constantly a mixing process and a corresponding treatment and development of the polymer product in the treatment tank 34 takes place.

The regulation of the quantity M in the treatment tank 34 between the two limit values M _max and M _min allows a real-time preparation without intermediate storage of the drug solution and a virtually immediate addition to the sludge of the prepared drug solution. As a result, the very young active ingredient solution L, which is still very young at the time of use, has a significantly increased effectiveness W on average compared with the prior art, which, as in FIG 5 and 6 shown very close to the maximum (relative) efficiency W _max of 100% and typically in a range between W _max = 100% and a minimum (relative) efficiency W _min = 90% = 0.9 W _max , preferably even between W _max = 100% and W _min = 95% = 0.95 W _max can be kept. Due to this high efficiency W of the treatment tank 34 taken drug solution L can be saved up to a significant amount of polymers of up to 30%. Furthermore, a mixed water saving of up to 90% is possible.

The Efficacy W of the drug solution L is expediently determined on the basis of the immediate result of the sludge treatment or measured. In particular, as a measure of the effectiveness W of the drug solution L of Degree of drying or degree of dehydration or solids content of remaining in the filter sludge residue or Dry sludge or filter cake are used. The less Contains residual water of the filter cake, the more more effective is the drug solution L been. Alternatively or in addition but also the so-called zeta potential of the polymers or polyelectrolytes as a measure of effectiveness W be used and measured.

The treatment plant can be operated as follows:
At system restart with empty preparation tank 34 First, a groundwater amount of water H without polymer addition in the treatment tank to through the level sensor 41 filled level. As soon as this "empty sensor" reports "covered", the mixing device switches to the drive 38 as well as the metering device for the active ingredient powder P and possibly the liquid active substance F added. The metered addition of the polymer mixture begins and the circulating mixture in the treatment tank 34 through the two zones Z1 and Z2 begins.

With increasing filling of the treatment tank 34 Next will be the min probe or the bottom level sensor 40 covered first and after a lot M _max - M _min , in particular 20 l, further fluid supply finally also the max probe or the upper level sensor 39 , whereby the Erstbefüllung is completed and turn off the mixing water and Polymerdosierzugabe.

After each addition of active ingredient, an adjustable basic mixing time always starts for the mixing device, after which the mixing device shuts off when no solution is requested from the filter system. Without dosing of drug solution L on the other hand, the mixer turns on continuously in the interval for one minute, so that the drug solution in this waiting time is not in the treatment tank 34 settles. Ready-made polymer solution L can now be used for the treatment tank 34 for dosing into the sludge in the pipe section 1 be removed.

In normal filter operation of the sludge runs at start signal, the mixing device with the mixing tool 37 and the conveying tool 35 in the treatment tank 34 as well as the solution pump 8th On and to the mud conditioning or treatment is the treatment tank 34 the amount M _max - M _{min is taken} from drug solution L until the minimum quantity sensor is traversed and a new post-dosing cycle begins.

When replenishing is preferably first the water valve 17 opened before the powder dosing switches back on, so that the water vortex in the mixing pot or vortex pot 21 can form first, before the active ingredient powder P is interspersed.

The water valve 17 in the water supply system 12 according to 1 and 2 is a special solenoid shut-off valve and preferably connected to the outlet of the sludge filter or bindbax, so that exclusively or at least partially filtrate water of the filtered sludge can be used in drug solution approach and thus a very economical sludge conditioning completely or partially without fresh water feed by recycling the Filtratwassers is possible.

The level sensor 41 serves as empty sensor for the mixing device and the solution pump. When falling below this minimum level, the drive 38 and the drive of the solution pump 8th shut down due to the dry run protection function. At the same time, the filter process on the filter machine is preferably also blocked until the treatment tank 34 refilled and again with its total volume up to the upper level sensor 39 is available.

The treatment system for treating conditioning agent or active substance solution for the treatment of a sludge according to the invention, in particular according to the illustrated embodiments, has the further advantage that over the number of cycles passing through the control within a predetermined time interval and the known difference M _max - M _min , which corresponds to the amount of replenishment during a cycle, the amount of active substance solution L passing through the entire system or the amount of water H metered in can be calculated.

Alternatively or additionally, the time duration tA of the weight loss phases of the preparation cycles can be measured, and the removal volume flow M _max -M _min / tA of the active substance solution L can be determined therefrom be that of the solution pump 8th currently subsidized flow rate corresponds. Further, the time tZ, according to the Zudosierphase measured in each processing cycle and the corresponding flow rate M _max - the extraction flow rate M _max M _min / tZ - added M _min / tA to the metered addition of volumetric flow for the water H and the active ingredients FH and P to get. This determination of the actual metered volume flow takes place practically in real time and is much more accurate than known inductive flow measuring systems.

By this continuous computational determination of the volume flows, in particular the volume flow of the added water H, is a water meter 18 as in 1 or other quantity measuring device no longer required and thus the simplified embodiment according to 2 possible.

Of the Extraction volume flow is typically between 200 l / h and 2500 l / h, the metered volume flow during the metering phases accordingly higher.

Furthermore, even a fully automatic delivery characteristic determination of the solution pump 8th , which is generally an eccentric screw pump, with different filter backpressure, which is typically between 0 and 16 bar depending on the progress of the treatment phase possible. For this purpose, it is detected or measured how often the pump rotates in a predetermined time interval, and on the thus determined frequency or speed of the solution pump 8th and the determined from the regulation and the number of refill cycles performed flow rate per unit time, in particular the delivery volume per unit time determined how powerful the pump is still. This can cause aging of the solution pump 8th be determined to advance a possibly required replacement of the solution pump 8th to be able to recognize.

3 now shows a further embodiment of a treatment tank 34 who also in 1 and 2 can be used. The mixing device with the mixing tool 37 and the conveying tool 35 on a common drive shaft 87 from a common drive 38 Being driven is no longer vertical as in 1 and 2 but arranged horizontally. The axis of rotation A is thus perpendicular to gravity, directed. The mixture FH + P is further from a vertically, ie parallel to the gravity, downwardly extending inlet pipe section 33 led down and into the treatment tank 34 brought in. The longitudinal axis of the inlet pipe section 33 and thus the main flow direction of the mixture FH + P is thus in contrast to the embodiments in FIG 1 and 2 in the embodiment according to 3 directed perpendicular to the axis of rotation A of the mixer.

To get a good suction effect of the propeller or conveying tool 35 to achieve is the inlet pipe piece 33 at his the conveyor tool 35 adjacent end 33A slanted and has by this bevel cut a the delivery tool 35 facing the mouth, from which the mixture FH + P directly on the suction side of the conveying tool 35 to be led. The cutting angle of the beveled end 33A of the inlet pipe section 33 is preferably 45 °, but may also differ slightly from this angle.

The mixing device with conveying tool 35 , Mixing tool 37 and joint drive 38 is according to 3 in a lower area of the treatment tank 34 arranged. Below the mixing device is again an outlet 52 of the treatment tank 34 provided, through which the ready-prepared drug solution L can be removed. Despite the according to 3 relative proximity of the outlet 52 to the likewise downward outlet 50 the mixing chamber 36 generates the conveying tool 35 Such a turbulent flow in the outer zone Z2 of the treatment tank 34 that at the outlet 52 it is possible to remove a solution of active substance L which has already been prepared virtually completely and which has passed through the mixing zone Z1 several times.

4 now shows a section through the mixing chamber 36 with the mixing tool received therein 37 as a mixing paddle with a central shaft 37A is rotationally symmetric about the axis of rotation A and two on the shaft 37A diametrically opposite fixed or integrally formed with this mixing blades 37B and 37C having. The wall of the mixing chamber 36 has a hollow cylindrical basic shape and has on its inner side extending parallel to the axis of rotation A bulges or caverns 87 on, in the example of the 4 have a semicircular cross section and the hollow cylinder segments as transition sections 88 connected to each other.

During the rotation of the mixing tool 37 will now be in the zone Z1 in the interior of the mixing chamber 36 solution and mixture of polymer and water mixed with high mixing energy input. Between two caverns 87 becomes the fluid mixture at the reach areas 88 led out and at the Abreißkanten formed there and the corre sponding edges of the mixing blades 37B and 37C exposed to strong shearing forces are mechanically reduced by the not yet completely dissolved polymer particles from outside to inside and de resolution is significantly accelerated.

By combining the high speeds of the mixing tool 37 and the cavern mixing chamber 36 the mixture FH + P passes through the first zone Z1 from the mixing tool 37 with high mixing energy 31 and with a comparatively short lead time excellent open-minded and homogenized. The mixture FH + P leaves the first zone Z1 as already predominantly developed active substance solution L. The development is improved each time the mixing zone Z1 passes and a mixture FH + P newly added by a subsequent addition is reopened again.

In the treatment tank 34 There is always a mixture of an already practically completely digested active substance solution L and a comparatively small amount of FH + P of a not yet disrupted mixture of solvent or solution of solvent and liquid active ingredient FH on the one hand and active ingredient powder P on the other hand. Since the ratio of the mixture FH + P and the drug solution L in the treatment tank 34 is less than 0.2 or even 0.15, the quality of the extracted drug solution L is also in the relatively small preparation times of a few minutes in the treatment tank 34 not negatively affected.

at the treatment process according to the invention for the preparation of polymer drug solution of polymer powder and / or Liquid polymer product will be on the basis of a consumption-quantity-controlled mixing of a variable polymeric amount of active ingredient with a quantity-proportional addition of water without use solution tank intermediate storage worked. The known from the prior art active substance aging by the storage tank storage is eliminated practically complete in this procedure, because the still young solution immediately used for dosing in the mud completely. Just alone with a changed one Parameter setting you can select a variety of mix solutions to to achieve more effective and more economical drainage results. It is also possible, special mix solutions on critical sludges set, without leaving residual amounts of remaining solution in the tank consider must as in the prior art. The low volume compared to the prior art of the treatment tank This application is very accommodating as well as the very simple one Adjustment of the active substance concentration. In this method is in a small mixing tank with only 150 or 160 l content over one Water valve, a powder metering lock and / or a liquid metering pump in a selectable one Mixing ratio polymer product introduced, wherein for intensive connection of the components a novel two-zone circulation mixture is used.

Claims (52)

Process for treating a sludge, in particular a sewage sludge or industrial sludge, in which a) at least one active substance (P) and at least one solvent (FH) are metered into at least one treatment vessel and processed into a solution of active substance and b) the at least one treatment vessel ( 34 ) is taken during at least one treatment period drug solution and the sludge is supplied, wherein c) in the at least one preparation tank, a circulation of the drug solution and the undissolved active ingredient (s) and solvent is generated, successively a first zone (Z1) and a second zone (Z2) of the preparation tank flows through, d) the active substance solution and the not yet dissolved active substance (s) and solvent in the first zone of at least one mixing tool ( 37 ), preferably under the action of shear forces and / or with a high mixing energy input, mixed or mixed. The method of claim 1, wherein the metered Active substance (s) and solvent first essentially be passed through the first zone of the treatment tank. Method according to Claim 1 or Claim 2, in which the first zone (Z1) is located from the interior of a mixing chamber arranged inside the preparation tank (Z1). 36 ) is formed and the second zone (Z2) outside the mixing chamber is formed in the treatment tank. The method of claim 3, wherein the mixing chamber is formed hollow cylindrical. Method according to one or more of the preceding Claims, in which the drug solution and the or the unresolved drug (s) and solvent vertically from top to bottom through the first zone (Z1). Method according to one or more of the preceding Claims, in which the mixing tool is rotated about a rotation axis and the drug solution and the or the unresolved drug (s) and solvent parallel to the axis of rotation of the mixing tool through the first zone (Z1) led become. Method according to one or more of the above claim, wherein the active substance solution and the not yet dissolved active substance (s) and solvent in the first zone are mixed or mixed by the at least one mixing tool under application of shear forces and / or with a high mixing energy input. Method according to one or more of the preceding Claims, in which a) the effectiveness of the processed drug solution by Degradation of the drug concentration in the drug solution continuously decreases b) the efficacy of the solution of active substance added to the sludge during the entire treatment period between maximum efficacy and one not more than 30% below the maximum efficacy minimal effectiveness. The method of claim 8, wherein the minimum effectiveness at least 0.8 times the maximum effectiveness. The method of claim 8, wherein the minimum Efficiency is at least 0.9 times the maximum efficacy. Method according to one of the preceding claims, in during that the treatment period continuously new drug solution in the treatment tank is processed. Method according to one or more of the preceding Claims, in which a) the during supplied during the treatment period Total amount of drug solution is greater than the from the treatment tank maximum intake capacity and b) during the treatment period continuously new drug solution in the same processing tank which is also taken from the active ingredient solution for the sludge. Method according to one or more of the preceding Claims, in which the located in at least one preparation tank amount of drug solution and not yet solved Active substance (s) and solvent at least during of the treatment period between a maximum amount and a Minimum amount that is larger as at least half the maximum amount is held. The method of claim 13, wherein the minimum amount at least 0.8 times the maximum amount. The method of claim 13, wherein the minimum amount at least 0.85 times the maximum amount. The method of claim 13, wherein the minimum amount at least 0.9 times the maximum amount. A method according to any one of claims 13 to 16, wherein a) new active ingredient solution in successive reprocessing cycles recycling bin is processed, where b) each treatment cycle on reaching or below the minimum amount in the treatment tank started becomes, c) in each preparation cycle c1) during a Addition phase active ingredients and solvents the treatment tank is added, wherein the metered flow rate at least in the temporal Medium is larger as the withdrawal rate of the drug solution, until the maximum amount is reached, and then the dosing is stopped again, and c2) while a weight loss phase as a result of the removal of active substance solution Amount in the processing tank decreases until the minimum amount is reached again. The method of claim 17, wherein the metered quantity stream the active substance (s) and solvent (s) and / or the removal amounts stream of the drug solution in each case substantially are or are constant over time. The method of claim 17 or claim 18, wherein the cycle duration of each conditioning cycle in a range between 1 minute and 10 minutes dialed becomes. The method of claim 17 or claim 18, wherein the cycle duration of each conditioning cycle in a range between 2 minutes and 8 minutes becomes. The method of claim 17 or claim 18, wherein the cycle duration of each conditioning cycle in a range between 3 minutes and 6 minutes becomes. A method according to any one of claims 17 to 21, wherein the Cycle time of each treatment cycle is less than the treatment period. A method according to any one of claims 17 to 21, wherein the Cycle time of each conditioning cycle by at least one factor 20 is smaller than the treatment period. A method according to any one of claims 17 to 21, wherein the Cycle time of each conditioning cycle by at least one factor 100 is less than the treatment period. A method according to any one of claims 17 to 24, wherein the cycle times of the conditioning cycles or the durations of their dosing phases or slimming phases that the preparation container during the Treatment period or part of the treatment period taken amount of drug solution or whose withdrawal rate is determined. The method of claim 25, wherein the determined Withdrawal flow during the the treatment period or part of the treatment period by means of a conveyor, in particular a feed pump, taken drug solution the current delivery characteristic or delivery rate the conveyor determined is, in particular by comparison with a speed of a drive the conveyor. A method according to any one of claims 17 to 26, wherein the cycle times of the conditioning cycles or from the time periods the dosing phases or the slimming phases of the treatment cycles the the processing tank while amount of solvent (s) added over a given period of time and / or active ingredient (s) or their metered-in flow rate determined becomes. The method of claim 27 when dependent on claim 25 or claim 26, wherein from the durations of one or more Abnehmenphasen the current withdrawal rate of drug solution determined and the metered mass flow during one or more preceding or subsequent dosing phases from the periods of these dosing phases and the determined extraction flow rate is determined. Method according to one or more of the preceding Claims, in which as active ingredient (s) a solution one or more polymers and / or polyelectrolytes used will or will be. Method according to one or more of the preceding Claims, in which, for the preparation of the active substance solution, active substance (s) in the form of solid particles, especially as a powder or granules is used or be and the particles of the drug (s) in the solvent be mixed. Method according to one or more of the preceding Claims, in the preparation of the drug solution, drug (s) or drug stock solution (s) in liquid Form is or are used and the / the liquid drug (s) in the solvent is mixed or become. Method according to one or more of the preceding Claims, in the case of the treatment of the sludge solid components of liquid be separated, especially the sludge is drained. The method of claim 32, wherein the sludge after the feeder the drug solution fed to a filter in which solid components of the sludge are filtered out. The method of claim 33, wherein the filter is penetrated Filtrate water as solvent for the Preparation of the drug solution is used. A method according to any one of claims 32 to 34, wherein the Degree of drying of the solid components of the sludge after their Separation from the liquid increases with the effectiveness of the drug solution. Apparatus for treating a sludge, in particular a sewage sludge or industrial sludge, comprising a) at least one treatment tank ( 34 ) for the preparation of active ingredient solution of at least one active substance (P) and at least one solvent (FH), b) at least one metering device ( 21 . 31 ) for metering the active substance (s) and the solvent (s) into the treatment tank, c) at least one feed device for removing active substance solution from the treatment tank and supplying this active substance solution to the sludge d) at least one mixing device for mixing of the active substance (s) present in the preparation container with the solvent (s), wherein the mixing device d1) comprises a mixing tool arranged within a first zone (Z1) of the preparation container ( 37 ) and d2) a conveying tool ( 35 ) in a separate from the first zone second zone (Z2) of the treatment area for generating a circulation of the drug mixture or active agent solution in the treatment tank by the first zone and the second zone. Apparatus according to claim 36, in which the metering device comprises a pipe piece projecting into the preparation tank ( 33 ), which opens at the negative pressure side of the conveying tool, comprises for transporting the active substance (s) and the solvent (s) to the conveying tool. Apparatus according to claim 36 or claim 37, wherein the conveyor tool and / or the mixing tool by one or a common Rotary axis (A) are rotatable or is or turn or rotate. Apparatus according to claim 38, wherein the axis of rotation (A) of the conveying tool directed substantially parallel or coaxial with the longitudinal axis of the pipe section is. Apparatus according to claim 38, wherein the axis of rotation (A) of the conveying tool substantially perpendicular to the longitudinal axis of the pipe section is directed and the pipe section at its end at the conveyor tool beveled side facing is. Device according to one or more of claims 36 to 40, wherein the first zone (Z1) from the interior of a mixing chamber arranged inside the treatment container ( 36 ) is formed and the second zone (Z2) outside the mixing chamber is formed in the treatment tank. Apparatus according to claim 41, wherein the mixing chamber has a hollow cylindrical basic shape. Apparatus according to claim 41 or claim 42, wherein the at least one predominant one Area of the pressure side of the conveying tool in fluid communication with the mixing chamber and the first zone formed therein stands and the remaining area of the pressure side of the conveyor tool in the second zone or directly with the second zone in fluid communication stands. Device according to one of claims 41 to 43, wherein the mixing chamber on its the inner wall facing the mixing tool, preferably parallel to the axis of rotation of the mixing tool extending caverns ( 87 ) having. Device according to one of claims 36 to 44, wherein the Blending tool has at least two mixing blades, preferably extend parallel to the axis of rotation of the mixing tool. Device according to one or more of Claims 36 to 45, in which the metering device comprises a solvent feed system for supplying solvent and a powder meter ( 31 ) for metering active ingredient powder (P) to the solvent. Apparatus according to claim 46, wherein the metering device comprises a vortex pot (14) connected to the solvent supply system ( 21 ) and the powder feeder is disposed above the vortex pot for delivering powdered drug into the vortex pot and solvent flowing therein. Apparatus according to claim 46 or claim 47, wherein the means for generating an air carrier stream for the active ingredient powder are provided and a baffle plate on the air carrier stream is directed with the active ingredient powder for its homogenization or is, wherein preferably the active ingredient powder from the baffle plate is led into the vortex pot or falls into it. Device according to one or more of claims 36 to 48, where the conveying tool is designed as a propeller. Device according to one or more of the preceding claims 36 to 49 further comprising a control or regulating device for Controlling or regulating the amount of drug solution or drug mixture between a maximum amount and a minimum amount, which is bigger than half the maximum amount. Apparatus according to claim 50 with a processing container associated Quantity measuring device, in particular level sensors or mixture sensors, for determining the amount in the treatment tank drug solution and mixture of drug (s) and solvent (s) or exceedance or falling below the maximum amount or the minimum amount. Device according to one or more of claims 36 to 51 for implementation A method according to any one of claims 1 to 35.