Patent EP-2256093-A1 (EP)
Inventor: ENGELHARDT KARL
IPC: C02F3/12
Filed: 2010-05-06
Abstract: The small-scale wastewater treatment plant with wastewater aeration by drafting of air over aerator openings and by a porous filter body made of mineralized filler material is claimed, where the filter body is introduced to a pre-clarification duct with an aeration space in a circular manner and the clarification water is directly introduced into an aerobic post-clarification filter after leaving the anaerobic septic tank without intermediate line, where the clarification water from the post-clarification filter is fed back again into a water-light-separate sampling chamber. The small-scale wastewater treatment plant with wastewater aeration by drafting of air over aerator openings and by a porous filter body made of mineralized filler material is claimed, where the filter body is introduced to a pre-clarification duct with an aeration space in a circular manner and the clarification water is directly introduced into an aerobic post-clarification filter after leaving the anaerobic septic tank without intermediate line, where the clarification water from the post-clarification filter is fed back again into a water-light-separate sampling chamber in the pre-clarification duct after the filter passage to pass the clarified water into a sewer system. The channel bottom is subdivided into slightly sloping, flat stepped areas in a spiral staircase manner, where the areas slow down the water flow. The channel bottom of the channel elements is combinedly coated with 2 cm thickness of upward open-porous layer made of single-grains having a grain size 8-16 mm. A loose layer having a thickness of 3 cm and made of gravel with a grain size of 4-8 mm is applied on the solid single-grain concrete layer in the channel bottom. The channel elements are laid with sustainable spacer holders, which are suspended at the edge of the pre-clarification duct and are provided with recesses decreasing from holder to holder in turn following the slope, where the channel elements are inserted into the recesses. The channel elements are prefabricated as quarter circle segments, in which the outer channel wall is so high that it closes itself towards the slope winding. The respective upper channel element lies on the bottom. The inner channel wall is lower, so that the channel opens towards inside to the aeration space and circulates the air transversely to the channel running direction. The filter body is formed from channel-shaped reinforced concrete elements, which spirally wind towards below, have a fine hole perforation in the channel bottom and flow into a separately divided four-chamber within a three-chamber septic tank where a water tank is formed for sampling with an overflow into a drainage pipe in the duct. In the channel-shaped concrete elements, a winding composed of 36 pieces of 10-grade segments, which have a single weight of 25 kg and are laid like bricks. The channel elements are provided with grooves and spring at the joining edges, have shaped concrete spacer blocks that form both the space to the pre-clarification duct and the inner vertical supports one upon the each other, and are laid with the prefabricated concrete spacer blocks in an adhesive bed of the cement mortar, so that so that a constant horizontal moving space to the pre-clarification duct and a strong inner vertical support of the channel elements are safely set. The number of holes of the perforation increases with the flow of the fall, so that the flow width of the clarification water and the infiltration capacity increase by the channels up to the lower collection winding. The upper part of the filter body is formed of flat reinforced concrete ring elements without fall, where the reinforced concrete ring elements are stacked one upon the other and are prefabricated as complete circle channels. The channel bottom are divided into sectional fields made of single-grain concrete having grain size of 8-16 mm and by pressure-tight, flat-mounted support beams made of reinforced concrete in the regular intervals. In the area of the filter clarification water inlet, the filter bottom of the uppermost ring is initially suspended with the cement mortar from below in a tight manner, so that a water distribution is given by increasing infiltration permeability. The outer channel wall is higher than the inner, so that a closed outer wall is formed towards inside during stacking but a circular air opening is given with the space to the pre-clarification duct. The lower collecting channels are sloped towards the outlet in the sampling duct.