RU2040482C1 - Device for biochemical sewage treatment - Google Patents

Abstract

FIELD: sewage treatment. SUBSTANCE: biofilter media is made in the form of balls having an increased surface due to recesses of irregular tapered shape with rounded off faces and vertices forming in pairs a symmetry in hemispheres, at whose combination the recesses are arranged in a staggered order. The device air tank is furnished with a cap, having the shape of a triangular prism. EFFECT: facilitated procedure. 7 dwg

Description

 The invention relates to biochemical treatment of domestic and wastewater close to them and can be used in wastewater treatment of small settlements and small industries, as well as in the chemical, microbiological, biotechnological industry.

 A device for biochemical wastewater treatment, comprising a feed pipe with additional pipes placed therein and caps in the form of flat domes, a biofilter with loading and a cylindrical shape, aeration tank settler.

 The feed pipe with additional pipes and caps in the form of flat domes located in it does not provide a uniform distribution of oxygen throughout the volume of the aeration tank and the necessary degree of mixing of activated sludge and supplied wastewater. The use of caps in the form of flat domes does not allow to accumulate a sufficient amount of air to increase the time of dissolution of oxygen in the aeration tank.

 The aim of the invention is the intensification of the wastewater treatment process by increasing their contact time with atmospheric oxygen.

 The goal is achieved in that in the device for biochemical wastewater treatment, the biofilter loading is made of balls with a diameter of 70 mm with eight irregularly shaped recesses with rounded faces and vertices converging to the center of the ball. The spherical shape of the elements contributes to the smooth spreading of liquid on the surface and increases the mass transfer properties of the loading elements. The absence of faces in the recesses and a fixed distance between spherical elements with a diameter of 70 mm excludes siltation of the load. The presence of recesses of the form described above eliminates the “dead” phase contact zones not washed by air and water. The active surface of this type of loading is reached 65-75%. The proposed volumetric loading form (ball with a diameter of 70 mm) is convenient in mass production. The size of the ball is optimally selected, since an increase in its diameter entails a decrease in the active surface of the biofilter loading, and a decrease leads to siltation of the load.

The shape of the recesses and their location in the load contributes to the effective removal of mineralized biomass, excluding siltation, lengthens the residence time of the waste fluid in the biofilter, contributing to an increase in the oxidative power of the biofilter. In this case, 1 m ^{3 of the} load accumulate up to 52 l of liquid.

 Sewage, having passed the biofilter loading through one part of the aeration columns, falls under the hood, and into the aeration zone of the aeration tank on the other. The cap is made in the shape of a triangular prism and is located in the lower part of the aeration tank aeration zone. The implementation of the cap of the proposed form is dictated by the need to accumulate more air in the zone of the highest concentration of activated sludge, which lengthens the time of its dissolution in the aeration zone. The aeration process occurs due to the involvement of air in the waste liquid in aeration columns. Getting under the hood and accumulating in it, the air leaves an ascending stream of bubbles from under the side of the hood, located at the dividing wall of the aeration tank and sump. At the same time, horizontal streams of water-air mixture are formed, leaving through the tangential nozzles located at the ends of the aeration columns not brought under the hood. Mutually perpendicular water-air flows allow to achieve greater mixing of wastewater with activated sludge. The above side of the cap is an inclined plane. It creates the possibility of directed collection of activated sludge and excludes zones of siltation of the aeration tank. An increase in the volume of the cap entails a decrease in the volume of the aeration zone, which reduces the oxidative power of the aeration tank. The air outlet is technologically more convenient to carry out along one side of the cap, which in this case is located in the lower part of the inclined plane, subject to additional air accumulation due to the shape of the cap.

 In FIG. 1 shows a device, a longitudinal section; figure 2 is the same, a cross section; figure 3 load element in the plan; figure 4 section aa in figure 3; figure 5 loading, longitudinal section; Fig.6 loading element with a cut in the recesses; 7, a loading element with a notch on the protrusions.

 The device includes a receiving chamber 1, aeration tank 2, a circulation pump 3, a hydraulic elevator 4, a biofilter 5 with an irrigation system 6 and a charge 7, a tray 8, aeration columns 9, a cap 10, a sump 11, a collecting tray 12 for purified water. The cap 10 is made triangular in shape. The loading is made in the form of balls with pyramidal indentations with rounded faces and vertices oriented to the center of the ball.

 A wastewater treatment device operates as follows.

 Wastewater that has been mechanically cleaned in sand traps and gratings (not shown) enters the intake chamber 1, which acts as a flow averager. The entire system is pre-filled with wastewater. The mixture of the initial wastewater and activated sludge, taken from the aeration tank 2 by the circulation pump 3 and from the receiving chamber 1 by the hydraulic elevator 4, is fed to the biofilter 5 through the irrigation system 6, where it is saturated with atmospheric oxygen. A liquid distributed over the loading surface 7 of the biofilter 5 washes the loading surface coated with biofilm and recesses filled with activated sludge. As a result, the wastewater undergoes biochemical treatment and is saturated with oxygen.

 In aeration tank 2, the process of oxidation of organic contaminants not retained by the biofilter takes place.

 Wastewater, passing through the load 7 of the biofilter 5, is collected by a tray 8 located under the biofilter 5 and sent to aeration columns 9, in which oxygen is also saturated with oxygen due to its absorption by the wastewater. The water-air mixture of one part of the aeration columns 9, arranged fan-shaped for uniform distribution of air throughout the volume of the aeration tank, falls under the cap 10, in which air accumulates. As it accumulates, air bubbles exit from under the hood in the form of an upward flow of a water-air mixture.

 Another part of the aeration columns 9, also fan-shaped, directs the water-air mixture to different points in the volume of the aeration tank 2. At the same time, mutually perpendicular water-air flows arise in the aeration tank, which ensures thorough mixing of activated sludge with the waste fluid and saturation with dissolved air oxygen. Waste fluid from the aeration tank enters the sump 11 through the gap between them and, passing a layer of suspended sludge, becomes clarified. The treated wastewater by the collecting tray 12 is discharged from the system.

 The invention has the following advantages.

For a working device:
reduction of wastewater treatment time by 10% with simultaneously increased quality of their treatment, since the use of new structural forms in the proposed device leads to an increase in the saturation of wastewater with atmospheric oxygen, reduces the duration of wastewater treatment and allows their treatment at a qualitatively increased level;
20% reduction in energy costs
reduction in operating costs.

If the device stops suddenly:
the ability to turn off the circulation pump for unforeseen reasons (power outage) for 6-12 hours, i.e. 2-3 times more than the prototype, since the use of the proposed load in the biofilter and the cap of the proposed form in the aeration tank creates the conditions for maintaining the vital activity of microorganisms.

Claims (1)

 DEVICE FOR BIOCHEMICAL WASTE WATER TREATMENT, comprising a housing separated by partitions into an aeration tank and a sump, a biofilter with a loading, an irrigation system and a tray, aeration columns, a receiving chamber, a hydraulic elevator and a circulation pump, characterized in that, in order to intensify the wastewater treatment process due to an increase in their contact time with atmospheric oxygen, loading is made in the form of balls with pyramidal depressions with rounded faces and vertices oriented to the center of the ball, and the aeration tank is equipped with lpakom in the form of a triangular prism.

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