DE2322511A1 - Effluent purificn. and sludge treatment plant - eliminating surplus activated sludge by aeration and biological decompsn. - Google Patents

Abstract

Purificn. of effluent, and treatment of the produced sludge, by thickening and dewatering and subsequent biological decompsn. in an aerating reactor. The biological material in the sludge for its biological decompsn. is formed and maintained alive up to the entrance of the sludge into the aerating reactor, while the oxygen required is supplied to the sludge during transport to the aerating reactor in the form of a gas or gas mixt. Sludge disposal problems are eliminated.

Description

Method for operating a wastewater treatment and sludge treatment plant and installation for carrying out the method The invention relates to a method for the operation of a wastewater treatment and sludge treatment plant, in which Clear sludge from wastewater treatment is thickened, drained and then drained is subjected to a rotting process in an aeration reactor and a system to carry out the procedure. The elimination of the sewage sludge causes more and more difficulties in most wastewater treatment plants because the open dumping of sewage sludge is becoming less and less possible, and agriculture also shows less and less interest in the use of sewage sludge.

Processes for biological sludge rotting are already known, However, all of which have the disadvantage that the necessary biology through Feeding additives containing this biology into the sludge treatment plant must first be generated in the latter, which is quite cumbersome and above all is time consuming, since the biology in the sludge treatment plant is tedious at first needs to be built.

The purpose of the invention is to create a wastewater treatment and Sludge treatment plant in which these disadvantages do not occur.

The inventive method is characterized in that one the biology present in the formation of the sewage sludge, the biological one Degradation of the sewage sludge is necessary until the sewage sludge enters the Keeping aeration reactor alive by adding the oxygen it needs to Form of a gas or gas mixture to the sewage sludge on its transport route to Ventilation reactor feeds.

To reduce the amount of gas or gas mixture to be conveyed and to increase the biological activity, it is useful if you use the sewage treatment plant and / or the sewage sludge to be fed from this to the aeration reactor on the Transport route between these two parts of the plant and / or the ventilation reactor supplies pure oxygen or air enriched with pure oxygen. To do it To have the least possible loss of oxygen, it is advantageous if one pure oxygen or air enriched with such oxygen in the aeration tank the sewage treatment plant introduces liquid and that from this escaping gas still containing oxygen from the waste water treatment plant the sewage sludge to be fed to the aeration reactor on the transport route between them feeds both parts of the plant and / or the aeration reactor.

To understand the biology during the transport of the sewage sludge from the Not to let the wastewater treatment plant for the aeration reactor die, but rather on the contrary, to activate it, it is useful if the sewage sludge is in the sewage sludge thickening and / or dewatering stage pure oxygen or one containing oxygen substantial increase to the biological Activity Activity is zortilnaft, when mari a diological conversion sprocess tss supporting gas or gas mixture passes through the ventilation reactor ü '# d rilt help of the gas mixture emerging from the latter when it is warmed up the liquid in the wastewater treatment plant and / or the Thickening and / or dewatering stage located sewage sludge is heated. Included it is useful if one is in the sewage treatment plant Liquid to increase the biological activity by at least 20C, preferably 5 to 10 ° C, compared to the inlet temperature of the liquid to be cleaned.

In certain cases it can be beneficial if to improve the biological activity taking place in the aeration reactor that in the aeration reactor sewage sludge to be treated is already treated before it is discharged into the reactor Well mixed.

It can be useful if you have at least two with each other connected basin provided wastewater treatment plant used, whereby one to purifying wastewater feeds the one acting as an aeration basin to the Wastewater in this pure oxygen or an oxygen mixture to be entered, and then the one enriched in this way with oxygen or an oxygen mixture Waste water is fed to the second basin, which acts as a secondary clarifier, and the clarified Water drains from this until the activated sludge concentration in the first basin is below drops a certain value, whereupon the operating direction is changed so that the second basin acts as an aeration basin and the first basin as a secondary clarifier.

The invention also relates to a system for carrying out the inventive method, which is characterized in that it at least a wastewater treatment plant and an excess sludge removal device connected to it has that the latter has at least one sludge thickening arrangement and a sludge dewatering arrangement is connected to an aeration reactor, and that aeration means are provided in order to remove from the sewage treatment plant withdrawn excess sludge on its way to the aeration reactor in oxygen In the form of a gas or gas mixture, to build a compact as possible It is useful if the treatment chamber of the aeration reactor is circular is trained. Two or more circular rings arranged one inside the other can also be used Treatment chambers are provided.

It is useful if the ventilation reactor has at least one treatment chamber for receiving the item to be treated, and that at least one fan for carrying out at least one that supports the biological conversion process Gas or gas mixture flow through the material to be treated, from the one Side wall of the treatment chamber to the opposite side wall of the the latter, and discharge means arranged on the underside of the treatment chamber for discharging the treated goods.

It is also advantageous if the initiation or

Suction of the gas or gas mixture flows formed side walls the treatment chamber into several areas provided with inlet and outlet openings divided and these areas separated from each other via flow regulators with at least one print or. Suction fans are connected.

In certain cases it is useful if the sewage treatment plant has at least two interconnected basins, and that the fluid supply and the fluid removal means and the means for introducing pure oxygen or an oxygen-containing gas in the liquid to be clarified in such a way with one another tied together are that in i # determining the one pool as animate seclums and the other Basin can be operated as a clarifier and vice versa.

The invention is explained below with reference to the drawing, for example explained. FIG. 1 shows, in section, an exemplary embodiment of a system according to the invention; FIG. 2 is a plan view of the one shown in FIG System; and FIG. 3 shows, on an enlarged scale, a section through a second example Embodiment of part of the system according to the invention.

As can be seen from Figures 1 and 2, the wastewater to be purified is via the supply line l, a chopper 2, a subsequent sand trap and one of the remote controlled inlet valves 3 and 3a immediately above the basins The sole is introduced into one of the two basins 4 and 4a. For example is the inlet valve 3 is open, then the inlet slide 3a is closed at the same time, so that the Wastewater only enters basin 4. The aeration turbine arranged in this basin 4 5 is set in rotation via the drive motor 6 and carries over the hollow drive shaft 7 supplied pure oxygen or oxygenated Air into the wastewater in the basin 4. The ventilation 4 turbine 5a is located yourself at rest. The drain arrangement 8a arranged in the basin 4a is open, while the drain arrangement 8 located in the other basin 4 is closed.

The wastewater entering the aeration basin 4 is at constant mixing with the activated sludge, the aerated wastewater-activated sludge mixture through the connection openings 10 located in the basin partition wall 9 into the Displaced neighboring basin 4a, which insofar has the function of a secondary clarifier assumes that the activated sludge is spread over the distance from the connecting openings 10 is deposited on the bottom of the pool up to the drain arrangement 8a. That from the activated sludge freed and biologically treated wastewater leaves this basin, which acts as a secondary clarifier 4a via the drainage arrangement 8a into the drainage channel 11 and passes through it pass a dip wall 12 in a finishing basin 13, in which also a Ventilation turbine 5b is arranged. This arrives again from the finishing basin 13 aerated water through the drainage channel 14 into the drain.

As in this training of the wastewater treatment plant the activated sludge constantly displaced from the pool 4 into the adjacent pool 4a and no longer returned becomes, occurs in basin 4 with increasing operating time a decrease in the concentration of activated sludge a. Below a certain activated sludge concentration there would be a strong decrease the cleaning performance. In addition, the activated sludge deposited in the basin 4a no more oxygen supplied, so that in this basin after a certain Operating time sequelae would wake up noticeably.

In order to rule out the above-mentioned consequences and ensure a perfect To ensure cleaning performance, the operation of the two basins 4 and there changed after a certain time. With this change, which takes place fully automatically, the ventilation turbine 5 switched off, the remote-controlled one Inlet slide 3 closed, the remote-controlled inlet slide 3a opened and the drain assembly 8a closed. With the standstill of the ventilation turbine 5 occurs a calming of the water movement in basin 4, so that the still in this basin 4 existing activated sludge can sediment. After a certain downtime the aeration turbine 5, the drain assembly 8 is opened, whereby the water drain is guaranteed again. At the same time, the ventilation turbine 5a in the basin 4a switched on and thus the sludge deposited in this basin 4a again brought into the necessary state of suspension and supplied with oxygen.

For the withdrawal of the excess sludge extends into each of the both basins 4 and 4a each have an excess sludge outlet 15 or lSa, via which the Excess sludge drawn off and a sludge thickener provided with a rake 16 17 is supplied0 The sludge water removed in the sludge thickener 17 is over a sludge water line 18 is fed to the feed line 1.

The thickened sludge is then passed to a sludge post-aeration arrangement 19 supplied, where by means of a rotary aerator 20 coming from the basin 4a, over the exhaust pipe 21 supplied oxygen-containing gas, mixed with Pure oxygen supplied via the supply line 22 from the oxygen generation system 23 is entered in order to preserve the biology contained in the extracted sludge and activate.

After the sludge ventilation arrangement 19, the thickened one arrives Sludge into a sludge dewatering arrangement 24 and from there via a mixed material addition arrangement 25 in an annular aeration reactor 26. When to preserve in the mud contained biology is required, the sludge can also be stored in the sludge dewatering arrangement 24 and / or the niche product addition arrangement 25 with pure oxygen or an oxygen-containing one Gas mixture are ventilated.

About the mixed material addition arrangement 25 can, if necessary, for the biological Conversion process in the aeration reactor 26 necessary biology are strengthened, by having part of the exiting at the bottom of the aeration reactor 26 treated material is mixed into the dewatered sludge via the mixed material addition arrangement 25 and so additionally biologically vaccinated.

The material to be treated in the annular aeration reactor 26 is over the rotating column provided with a conveyor arrangement 27 and the distributor arms 28 evenly and continuously from above into the circular treatment chamber 29 of the aeration reactor 26 filled.

It goes without saying that it is necessary to achieve the best possible result It is also possible to use the garden area, two or more nested, To provide circular treatment chambers 29.

The treatment channel 29 has a medium diameter, for example of 72cm, a clear width of 4m and a usable filling height of 7m, that means a usable capacity of approximately 6200m3.

The treatment chamber 29 is divided into 12 chamber sections along its circumference subdivided by 300 arc lengths each, whereby overhaul work on individual chamber sections are possible without interrupting the operation of the entire system.

Seen over the scope of the treatment chambers 29, the individual Treatment chamber sections on the radially inward and the outward directed side wall each with a suction chamber provided with suction openings 30 or formed with a pressure chamber 31 provided with injection openings.

About the pressure chamber 31 is an oxygen mixture in the Treatment chamber 29 is introduced sludge. This creates in the Pasteurization zone 0 temperatures from 75 to 85 C.

The suction chamber 30 is provided with a suction fan, not shown connected, which is via the suction openings in this side wall a strongly heated gas or gas mixture is sucked off and through in the sludge thickening and -post ventilation arrangement 17 and 19 and the basin 4 and 4a arranged heat exchangers 32 for heating the thickened sludge or that in the two basins 4 and 4a located wastewater, which the biological activity is considerable increased and at the same time utilizes the heat dissipated from the ventilation reactor 26.

For heating the wastewater in the two basins 4 and 4a it is also conceivable that this is carried out via a heat exchanger through the cooling water of a To heat nuclear reactor.

If the gas or gas mixture extracted via the suction chamber is still has a sufficient oxygen content, this can be used to further utilize the Oxygen also the mud post-aeration - and / or sludge drainage arrangement 19 and 24 are supplied.

FIG. 3 shows a section through an aeration reactor, in which two nested, annular Behsndlungsksmmern 29 and 29a are provided.

In this arrangement, the radially inward and the outwardly directed side wall of the two treatment chambers 29 and 29a per treatment chamber section three chambers 30a, 31a, 31a 'or 30b, 31b, 31b 'arranged.

The suction and pressure chambers each have a controllable valve connected to a suction or pressure fan.

Thanks to the horizontal division into three zones, it is possible to use the sludge to be aerated in a diagonal direction, for example from 31a to 30b or vice versa and then from 31b to 30a or vice versa with pure oxygen or an oxygen-containing gas to ventilate, resulting in perfect ventilation is achieved.

It is also possible, for example from chambers 31a and 31b the end to ventilate only with pure oxygen and from the chambers 31a 'and 31b' with air.

When the chambers 31a, 31a ', 31b and 31b' as pressure chambers and the Chambers 30a and 30b act as suction chambers, is also extracted from above from the outside atmosphere Air through the sludge at the top of the treatment chambers to the Suction chambers 30a and 30b sucked. Here, too, this can be done through the suction chambers 30a and 30b sucked off heated gas or gas mixture for heating the to be thickened Sludge and / or used to heat the wastewater to be treated.

The chambers can also, as in FIG. 3, on the left band hole chamber 29 shown on the left as an example, using adjustable release agents 33 must be connected to each other, so that it is e.g. possible to use a single lxaw er 30a, 31a 'or two individual chambers 30a and 31a' with different pressure ratios to build.

To ensure that the treatment chambers 29 and 29a treated goods perfectly in the vertical direction down to the discharge point slips, the treatment chambers are designed as shown in the drawing, that they widen slightly conically towards the bottom.

Furthermore, it is easily possible to do so in the aeration reactor 26 treated sludge to loosen it up additionally with crushed tulle or Mix in peat.

Claims (28)

Patent claims Process for the operation of a wastewater treatment and sludge treatment plant, in which sewage sludge originating from wastewater treatment is thickened, dewatered and is then subjected to a rotting process in a ventilation reactor, characterized in that the formation of the sewage sludge in this existing biology, which is necessary for the biological degradation of the sewage sludge, is kept alive until the sewage sludge enters the aeration reactor by the oxygen required for this is added to the sewage sludge in the form of a gas or gas mixture on whose transport route to the aeration reactor. 2. The method according to claim 1, characterized in that one of the Wastewater treatment plant and / or that to be fed from this to the aeration reactor Sewage sludge on the transport route between these two parts of the plant, and / or the Aeration reactor pure oxygen or air enriched with pure oxygen feeds 3. The method according to claim 2, characterized in that pure oxygen is used or enriched with such Air into the in the aeration tank Wastewater treatment plant introduces liquid and that from this escaping gas still containing oxygen from the waste water treatment plant the aeration reactor to be fed sewage sludge on the transport route between them feeds both parts of the plant and / or the aeration reactor. 4. The method according to claim 1, characterized in that the Purify sewage sludge in the sewage sludge thickening and / or dewatering stage Supplies oxygen or an oxygen-containing gas. 5. The method according to one or more of the preceding claims, characterized in that one supports the biological conversion process Gas or gas mixture passes through the aeration reactor and this after the exit from the latter, the sewage sludge indentation and / or dewatering stage for aeration of the sewage sludge located in this. 6. The method according to one or more of the preceding claims, characterized in that one supports the biological conversion process gas or gas mixture passes through the ventilation reactor and with With the help of the gas mixture emerging from the latter in a heated state, the in the waste water treatment plant and / or the liquid in the thickening and / or the sewage sludge located in the dewatering stage is heated. 7. The method according to one or more of the preceding claims, characterized in that one is located in the wastewater treatment plant Liquid o to increase the biological activity by at least 2 C preferably 5 to 100C compared to the inlet temperature of the liquid to be cleaned a heat exchanger through which, for example, the heated cooling water of a nuclear reactor is conducted, heated. 8. The method according to one or more of the preceding claims, characterized in that the sewage sludge to be treated in the aeration reactor previously treated material is mixed in before it is discharged into the reactor. 9. The method according to claim 8, characterized in that 5 to 20%, preferably 5 to 10%, of already treated material mixed with the sewage sludge. 10. The method according to one or more of the preceding claims, characterized in that the sewage sludge to be treated from above into a preferably ring-shaped treatment chamber of an aeration reactor fills in, then the material to be treated continuously from one side wall the treatment chamber towards the opposite side wall of the latter with at least one gas or gas that supports the biological conversion process. Gas mixture flow permeated, and the treated at the bottom of the treatment chamber Well discharges, so that an automatic throughput of the goods to be treated in vertical Direction from top to bottom through the treatment chamber takes place. 11. The method according to one or more of the preceding claims, characterized in that it is used to support the biological conversion process a gas mixture containing oxygen, such as air, or pure oxygen guides through the item to be treated. 12. The method according to claim 10, characterized in that the Gas or gas mixture with at least one pressure fan on one side wall conveyed into the treatment chamber into the item to be treated and with at least one suction fan sucks off the opposite side wall. 13. The method according to claim 12, characterized in that the Gas or gas mixture flow in different diagonal directions through the treatment k & n # r '# r directs. 14. The method according to one or more of the preceding claims, characterized in that one is connected to at least two Basin-provided wastewater treatment plant is used, whereby the to be cleaned Wastewater is fed to a basin acting as an activation jack to remove the wastewater to enter pure oxygen or an oxygen mixture in this, and then that wastewater enriched in this way with oxygen or an oxygen mixture to the second supplies the basin acting as a secondary clarifier and removes the clarified water from it, until the activated sludge concentration in the first tank falls below a certain value sinks, whereupon the operating direction is changed, so that the second basin as Aeration basin and the first basin acts as a secondary clarifier. 15. The method according to one or more of the preceding claims, characterized in that the sewage sludge is added to the aeration reactor before it is introduced Adding dry matter such as garbage or peat. 16. Plant for carrying out the method according to one or more of the preceding claims, characterized in that it has at least one wastewater treatment plant (4 to 14) and an excess sludge removal device connected to it (15,15a) shows that the latter has at least one sludge thickening arrangement each (17) and a sludge dewatering arrangement t24) with an aeration reactor (25) is connected, and that aeration means (20) are provided to the from the sewage treatment plant (4 to 14) withdrawn excess sludge on its way to the aeration reactor (25) Add oxygen in the form of a gas or gas mixture. 17. Plant according to claim 16, characterized in that the treatment chamber (29) of the aeration reactor is circular. 18. Plant according to claim 16 or 17, characterized in that the ventilation reactor has at least one treatment chamber (29) for receiving the to has to be treated, and that at least one fan for passing through at least a gas or gas mixture that supports the biological conversion process through the material to be treated, namely from one side wall of the treatment chamber (29) towards the opposite side wall of the latter, and on the underside the treatment chamber (29) arranged discharge means for discharging the treated Good, are provided. 19. Plant according to claim 17 or 18, characterized in that they have at least two circular treatment chambers (29,29a) arranged one inside the other having. 20. Plant according to claim 17, characterized in that the circular ring-shaped Treatment chamber <29) along its circumference in individual parts through a partition is divided into separate sections. 21. Plant according to claim 18, characterized in that the for Introduction or suction of the gas or Gas mixture flows formed side walls of the treatment chamber (29) into several with inlet and outlet openings marked areas (30a, 31a, 31a ', 30b, 31b, 31b') and these areas are separated from one another Connected via flow regulators with at least one pressure or suction fan are. 22. Plant according to claim 21, characterized in that the for Introduction or suction of the gas or gas mixture streams serving side walls are designed as double walls, the interior of which by dividing walls into individual Chambers is divided. 23. Plant according to claim 21, characterized in that the for Introduction and / or suction of the gas resp. Gas mixture streams serving side walls formed as double walls are, the interior of which can be divided into individual chambers by adjustable separating means is, and that on the side of the double wall facing away from the treatment chamber the side wall areas corresponding to the individual chambers are separated from one another Connected via flow regulators with at least one pressure or suction fan are. 24. Plant according to claim 17, characterized in that around the central axis the annular treatment chamber (29) rotatable from the central axis to Treatment options (29) reaching distribution means (28) for distributing the material to be treated from the Central axis are provided in the treatment chamber (29). 25. Installation according to one or more of the preceding claims 16 to 24, characterized in that the wastewater treatment plant has at least two having interconnected basins (4,4a), and that the fluid supply and the liquid discharge means and the means (5, 5a) for introducing pure oxygen or an oxygen-containing gas in the liquid to be clarified in such a way with one another are connected that intermittently one basin (4) as an aeration basin and the other basin (4a) can be operated as a secondary clarifier and vice versa. 26. Installation according to one or more of the preceding claims 16 to 25, characterized in that the treatment chamber (29) of the ventilation reactor (25) widens conically downwards. 27. Plant according to claim 17 or 19, characterized in that the interior space of the aeration reactor bounded by the treatment chamber (29) (25) to form a e.g. the control center receiving room is covered. 28. Plant according to claim 17 or 19, characterized in that the entry and discharge means of the aeration reactor (29) at a common, vertically extending rotatable shaft (27) are attached. Blank page