DAUZUC is a device for the treatment in the built wet area and the evacuation of wastewater treated by the capillarity of the soil and evapotranspiration in the atmosphere.
Charging with wastewater followed by capillary absorption into the soil layer creates a water pump that increases the capillary action of the soil layer in the basin.
Gradually, water stored in the soil is taken up by plant roots or evaporates from the soil surface into the atmosphere. Without additional water, the soil will gradually dry out.
DAUZUC obtains by increasing the rate of capillary absorption and due to the heat input brought by the discharged wastewater and the exothermic biological processes of the microorganisms, evapotranspiration values 6 mm / day (annual average).

The process is continuous and consists of:
– Mechanical treatment in the tank:
When the wastewater falls into the tank, the liquid part enters the filter tube distributing through the slots, and flows on the drain channel at its base, distributing evenly in the gravel layer, through the slits located outside the tank. Organic bodies larger than the width of the slots are retained.
– Biological treatment in the tank and in the built-up wetland
In the tank, the anaerobic digestion of biodegradable materials alternates with the aerobic digestion, depending on the variation of the wastewater flow and the load of the built wetland. Aeration is achieved by circulating air between the absorption tube and the exhaust tube but also due to the flow of water that enters the tank from the wet area built to reach the level of the distributor filter tube. This influx also enriches the content of aerobic microorganisms, with those in the built wetland. They are retained in the tank until transformed into liquid by aerobic biodigestion, feces and paper. Due to
the turbulence generated by the periodic level variations in a basic cylindrical space, the biodigestion is amplified, the liquefaction time being reduced to a few days. Under these conditions, the required volume of the tank is 5-10 times smaller than that of septic tanks or traditional treatment plants.
In the tank, the anaerobic and denitrification phase is performed for the elimination of nitrogen gas, after the nitrification in the built wet area and the anoxic phase of the phosphorus elimination. Here takes place the aerobic digestion of biodegradable materials by the stationary bio-media existing in the soil which, due to the variable flow of wastewater and level variations in multilayer, is submerged and aerated alternately, each time the level of the distributor filter tube is exceeded. to the water inside the tank and its exit in the gravel layer and its withdrawal due to the absorption by capillarity by the natural soil layer. Aeration inside the gravel layer and in the soil is intensified both by the convection caused by the movement of water infiltration through the granular medium and by the diffusion of air from the surface to the layer of granular material, by absorption in porous media. Ammonium nitrification (biological oxidation) also occurs due to chemoautotrophic bacteria, as well as denifrification at its base, by aerobic microorganisms when dissolved oxygen consumes oxidized nitrogen instead of oxygen, and by aerobic microorganisms. They convert nitrites and nitrates into gas in the form of
nitrogen (N2). Due to the organic load in the soil and the permanent aeration, the elimination of phosphorus also takes place. DAUZUC also purifies the water through two filtration processes, namely:
– surface filtration of the treated water, through which the medium-sized solid suspensions are removed by retention in the pores of the gravel bed, until the proportional dissolution in the effluent. Given that the solid suspensions retained are both of mineral and biological origin, it results that the process of surface filtration removes the suspended materials and a significant part of the organic load of the water undergoing the treatment;
– the final filtration of the water subjected to the treatment, through which the solid suspensions are removed
almost entirely when the water exceeds the level of the geotextile membrane which allows only the passage of clean water.
Biodegradation and disintegration of organic compounds and filtration is continued by microorganisms aerobedin the plant soil, also activated by the absorbed air.

The process is continuous and consists of:
1. Mechanical treatment in the tank in which solids and larger than the slots are retained in the tank
2. Biological treatment in the tank, by digestion, performed by aerobic and anaerobic microorganisms existing in wastewater but also migrated from the soil layer to total or partial liquefaction to the size of the slits.
3 Biological treatment in gravel, geotextile and soil layers.
The liquid and solids under the size of the slots are drained through slits in the gravel layer where they are purified by biofilm type biological filter , which is formed in the gaps between the stones in the gravel layer, in the soil layer and the geotextile material above it.
4 Discharge of water treated by capillarity and evapo-perspiration.

Technical data to be provided by the beneficiary
*) depth must be at least 0.95 m from the base of the sewer pipe to the penetration into the pit to the base of the pit.
The filling with earth must be made in such a way that it always remains in the embankment (hill) from the surrounding area.
TYPE EL Lxlxh *) Gravel 16-30.5 mm c.m.
DAUZUC 2-4 2-4 4x3x1.5 9
DAUZUC 6 6 6x3x1.5 15
DAUZUC 10 10 10x3x1.5 30
DAUZUC 20 20 20x3x1.5 60
DAUZUC 30 30 30x3x1.5 90
DAUZUC 50 50 50x3x1.5 150
DAUZUC 100 100 100x3x1.5 300