DE4428052A1

DE4428052A1 - Water treatment assembly soil-layers separated by porous fleece mat

Info

Publication number: DE4428052A1
Application number: DE19944428052
Authority: DE
Inventors: Juergen Wittlich; Bernd-Ulrich Dipl Ing Wilk
Original assignee: WILK BERND ULRICH DIPL ING; WITTLICH JUERGEN DIPL BAU ING
Current assignee: WILK BERND ULRICH DIPL ING; WITTLICH JUERGEN DIPL BAU ING
Priority date: 1994-07-29
Filing date: 1994-07-29
Publication date: 1996-02-01

Abstract

Water effluent is biologically and physically filtered and cleaned in an assembly with growing plants. The novelty is that the assembly is sub-divided into layers by a slightly rippled drain mat which extends upwards to the surface of the plant bed and extending over the rim of the assembly. Fluid passing through the drain mat absorbs ambient oxygen as it moves towards the plants. The fluid effluent draining through the plant bed and drain mat subsequently drains through an absorption stage containing pref. active carbon granules. The drain mat is a fleece non-woven fibre 15 to 50mm thick of air permeability up to 200 kN/m<2>. The grain mat is covered with a filter fleece on both sides with a kf value of approx. 10<2>m/s and made of a material resistant to micro-organisms, aggressive water effluent and moulds.

Description

Die Erfindung betrifft eine Anlage zur biologisch - adsoptiven Reinigung von mit Schadstoffen belastetem Abwasser in einem bewachsenen Bodenfilter - Pflanzenkläranlage (PKA).The invention relates to a plant for the biologically adsorptive cleaning of pollutants contaminated waste water in an overgrown soil filter - sewage treatment plant (PKA).

In der DE 40 41 241 A1 wurde ausführlich über den Stand der Technik zu horizontal und vertikal durchströmten Bodenfiltern diskutiert. Mit entscheidend für die Reinigungsleistung einer PKA ist die Durchströmung des Bodenfilters bei gleichzeitig ausreichender Versorgung der Mikroorganismen mit Luftsauerstoff. Normalerweise erfolgt die Sauerstoffversorgung über die Rhizome und das Wurzelwerk der Pflanzen, die für höher belastete Abwässer oft nicht aus reichend ist. Insbesondere im Hinblick auf eine gezielte Nitrifikation ist der damit verbundene Sauerstoffbedarf nicht zu decken. Ein weiteres Problem stellt die gezielte Entfernung von Nitrat des nitrifizierten Abwassers dar. Da der kohlenstoffhaltige Anteil im Abwasser vor der Nitrifikation weitestgehend abgebaut wird, fehlt der notwendige Kohlenstoff zur Deni trifikation, der auch nicht durch abgestorbene und in Lösung gehende Pflanzenreste gedeckt werden kann.In DE 40 41 241 A1, the state of the art was too detailed and horizontal vertically flowed bottom filters discussed. Crucial for the cleaning performance A PKA is the flow through the floor filter with sufficient supply at the same time of microorganisms with atmospheric oxygen. The oxygen supply is usually via the rhizomes and the roots of the plants, which are often not suitable for more polluted wastewater is sufficient. With regard to targeted nitrification in particular, this is associated with Not meeting oxygen needs. The targeted removal of Nitrate of the nitrified wastewater. Since the carbon-containing fraction in the wastewater before Nitrification is largely reduced, the necessary carbon for deni is missing trification, which is also not covered by dead and dissolving plant remains can be.

Erfindungsgemäß wird die Aufgabe dadurch gelöst, daß für die Sauerstoffversorgung in einem vertikal durchströmten Bodenfilter über die gesamte Länge des Beetes, im Querschnitt zwischen zwei Bodenschichten eine Drainmatte gelegt wird, die leicht gewölbt sein kann. -Fig. 1- Diese Drainmatte ist an den seitlichen Rändern der PKA über die Oberkante des Bodenfilters zu führen. -Fig. 2- Ein Aufstauen hat im Normalbetrieb nur noch unterhalb der Drainmatte zu erfolgen. Durch die "Kaminwirkung" wird somit auch in die unteren Schichten des Bodenkörpers Luftsauerstoff herangeführt, der zu einer Verbesserung der Reinigungsleistung u. a. der Nitrifikation führt. Im angestauten unteren Bereich der Anlage bilden sich anoxische Zonen, in denen der noch vorhandene Kohlenstoff für Denitrifika tionsvorgänge veratmet wird. Dieses Prinzip ist bei horizontal/vertikal durchströmten Anlagen analog anzuwenden. Hier ist der Einbau der Drainmatte in der Mitte der Längsseite des Beetes beginnend bis zum Auslauf vorzunehmen. Durch den am Boden befindliche Auslauf stellen sich die gleichen Verhältnisse wie bei vertikal durchströmten Anlagen ein. Auch hier ist ein Anstauen im unteren Bereich, bis maximal zur Unterkante der Drainmatte zur Ausbildung anoxischer Zonen, vorzunehmen. -Fig. 3-.According to the invention the object is achieved in that a drain mat is placed in the cross section between two soil layers for the oxygen supply in a vertically flowed bottom filter over the entire length of the bed, which can be slightly curved. - Fig. 1- This drain mat is to be run on the side edges of the PKA over the upper edge of the floor filter. - Fig. 2- In normal operation, the accumulation only has to take place below the drain mat. As a result of the "chimney effect", atmospheric oxygen is thus also introduced into the lower layers of the floor body, which leads to an improvement in the cleaning performance, including nitrification. Anoxic zones form in the pent-up lower area of the plant, in which the carbon still present for denitrification processes is breathed in. This principle is to be applied analogously for systems with horizontal / vertical flow. Here, the drain mat must be installed in the middle of the long side of the bed, starting at the outlet. The outlet located on the floor creates the same conditions as for systems with vertical flow. Here too, build up in the lower area up to a maximum of the lower edge of the drain mat to form anoxic zones. - Fig. 3-.

Die im nitrifizierten Abwasser enthaltenen Nitrate sind gut löslich. Aufgrund des Fehlens ausreichender C-Quellen ist eine gezielte Denitrifikation unter anderem über externe Kohlenstoffquellen möglich. Erfindungsgemäß wird die Aufgabe dadurch gelöst, daß dem Bodenfilter eine getauchte Adsorptionsstufe nachgeschaltet wird. Diese hat außer dem Vorteil der Bereitstellung von C-Indikatoren für eine Denitrifikation (Abbau des Nitrates in unschädliche Komponenten) aber auch die Bindung von möglicherweise im Abwasser enthaltenen Lösungsmittelanteilen, MKW usw.The nitrates contained in the nitrified wastewater are readily soluble. Because of the lack Adequate C sources include targeted denitrification, including via external ones Carbon sources possible. According to the invention the object is achieved in that the Soil filter is followed by a submerged adsorption stage. This has the added benefit the provision of C indicators for denitrification (degradation of the nitrate in harmless components) but also the binding of possibly in wastewater contained solvent components, MKW etc.

Claims

1. Plant for the biological and physical purification of waste water contaminated with pollutants in an overgrown soil filter - plant sewage treatment plant (PKA) - characterized in that different soil bodies are separated by a drain mat, this is led over the pool edge of the PKA to the surface of the plant bed and thereby contact with the ambient air. That the PKA is followed by an adsorption stage, preferably made of activated carbon.

2. Plant for the biological and physical purification of contaminants Waste water in an overgrown soil filter - plant sewage treatment plant (PKA) - according to claim 1, characterized in that synthetic resins or other suitable as adsorbents Materials are used.

3. Plant for the biological and physical purification of contaminants Waste water in an overgrown soil filter - plant sewage treatment plant (PKA) - according to claim 1, characterized in that the adsorbent is constantly in the nitrified waste water is immersed and can flow around the effluent.

4. Plant for the biological and physical purification of contaminants Waste water in an overgrown soil filter - plant sewage treatment plant (PKA) - according to claim 1, characterized in that the drain mat preferably has a thickness of 15 mm to 50 mm is used.

5. Plant for the biological and physical purification of contaminants Waste water in an overgrown soil filter - plant sewage treatment plant (PKA) - according to claim 1, characterized in that the drain mat is permeable to air at pressures of up to 200 kN / m² remains.

6. Plant for the biological and physical purification of waste water contaminated with pollutants in a vegetated soil filter - plant sewage treatment plant (PKA) - according to claim 1, characterized in that the drain mat is provided on both sides with a filter fleece and a k _f value of approx. 10² m / s.

7. Plant for the biological and physical purification of contaminants Waste water in an overgrown soil filter - plant sewage treatment plant (PKA) - according to claim 1, characterized in that the materials used for the drain mat are resistant against microorganisms, aggressive waste water, fungi, mold.

8. Plant for the biological and physical purification of contaminants Waste water in an overgrown soil filter - plant sewage treatment plant (PKA) - according to claim 1, characterized in that the PKA in normal operation up to at most the lower edge of the Drain mat is pent up and only to supply the reed plants in water shortages is flooded.