RU98997U1 - INSTALLATION OF BIOLOGICAL SEWAGE TREATMENT - Google Patents

Abstract

 1. Installation of biological wastewater treatment, which includes an averager, a chain of stages of aeration treatment by microorganisms, denitrification by microorganisms, a sump, the third stage of aeration treatment with membrane filtration and airlifts, a polystyrene filter, and also including a UV irradiation unit, characterized in that has at least the same two chains, passing through each of which the wastewater passes one after another two stages of aeration cleaning by microorganisms, in the last of which proceeds nitrification and denitrification partial flow, in a third stage of purification aeration and aeration is increased relative to the other stages, wherein aeration systems are provided as the third stage membrane aeration purification. ! 2. Installation of biological wastewater treatment according to claim 1, characterized in that the devices for the distribution of wastewater in the chains after the averager are gates.

Description

The biological wastewater treatment plant is designed to treat effluents discharged from residential and office buildings.

From patent No. 2201405 RU a device for wastewater treatment, including

- equalizing tank with activated sludge and wastewater supply, a pump for pumping raw water into the activation tank,

- activation tank having air inlet with an aerator,

- the discharge of raw water into the sump and pump for pumping sludge,

- sump, configured to remove sludge and the release of purified water,

- Control block,

The device is equipped with a housing with a lid for accommodating equalization and activation tanks, in which a level sensor is installed, and the side walls of each of the tanks are connected by stiffeners.

Moreover, the device is additionally equipped with an aeration chamber located in the housing with a porous filter and a stabilization chamber for activated sludge.

The sump is installed in the activation tank and is made in the form of a truncated pyramid, the smaller base of which is facing down, and is equipped with an outlet nozzle equipped with a soothing chipper and a protective visor covered from below.

A soothing chipper and a visor are located above the aerator of the activation tank, equipped with a biological charge and connected to a sump having an airlift damper and a sludge recirculation pump to the sludge stabilization chamber, equipped with a coarse-bubble aerator and an overflow pipe to drain excess water and sludge to the equalizing tank, and the sludge tank aerator to dilute the biological film removed by the airlift, as well as an overflow pipe for the release of purified water into the porous chamber filter equipped with an aerator, a pump for pumping purified water into the tank - stormwater - overflow pipe connected to a drive installed in the equalizing tank and equipped with airlift for pumping water from the drive to the equalizing tank, and in the equalizing tank, a pump for pumping raw water to the activation the tank is enclosed in a filter for cleaning coarse sewage.

A known method of wastewater treatment (patent No. 2201404 RU), including biological disposal with nitri-denitrification, which occurs in the first stage of treatment, and disinfection of hydrobionts in the second stage.

Known methods of disinfecting water due to UV radiation (patents No. 2288189, 1225819).

From the patent No. 2229198 RU a device for aeration is known in which a finely bubble aerator is attached to the lower part of the biological load.

The closest analogue is the method of wastewater treatment (patent No. 2068811 RU) using a treatment station using two stages of treatment with activated sludge, intermediate clarification between the first and second stages of treatment, secondary clarification after the second stage of treatment and sludge circulation.

The first stage of wastewater treatment is carried out aerobically as an adsorption stage with a sludge load equal to at least 2 kg of BOD5 per kilogram of dry substance per day or optionally anaerobically, mainly with prokaryotes in the working biomass. The second stage of wastewater treatment with activated sludge is used as an aerated stage with a sludge load of less than 0.15 kg BOD5 per kilogram of dry substance per day. The sludge from the secondary clarification is at least partially reintroduced into the adsorption step.

The aim of the invention is to increase the cleaning efficiency while optimizing costs.

In the proposed installation, which includes averaging runoff, three stages of cleaning with aerobic microorganisms, a denitrification stage with microorganisms, a settling tank, membrane cleaning, filtering and irradiation with UV radiation, the goal is achieved due to the fact that the waste stream after averaging passes sequentially through two stages of cleaning with aerobic microorganisms. As a result, in the second stage, due to low loads, nitrifying cultures develop, oxidizing ammonium nitrogen to nitrite and then to nitrate. In the depths of the biofilm of the same loads with the biocenosis of microorganisms under conditions of oxygen deficiency, denitrifying microorganisms develop, therefore, the denitrification of runoff begins in the second stage.

Further, the stock passes denitrification by microorganisms in a tank without aeration. As the silt mixture passes through the carrier blocks by specialized microorganisms, nitrates are reduced to molecular nitrogen. As a result, there is a decrease in the concentration of nitrates in the effluent. Due to the lack of mixing, all suspended particles are intensively fixed on the biofilm covering the loading surface.

Also, the cleaning efficiency is increased due to the third stage, where in conditions of intensive aeration (aeration is higher relative to other stages), the deep oxidation of organic substances carried out from the previous stages and the saturation of the purified water with oxygen take place. The capacity of the third stage is equipped with a membrane cleaning unit. As a result, the effluent mixture is filtered, the concentrated mixture is recycled to the tank, excess activated sludge is removed from the system, and purified water flows by gravity into the filter.

The membranes are equipped with an aeration system, which allows for the biocenosis of activated sludge with dissolved oxygen, to maintain a suspension of activated sludge and wastewater in suspension, and also to turbulent the flow at the membrane surface to prevent clogging.

The installation includes at least two cleaning circuits described above. Moreover, the number of working circuits can be quickly changed, due to which the flexibility of changing performance depending on the load and reducing cleaning costs is achieved. Changing the duration of the system, in order to optimize the urgent costs at the predicted load, can be done using gates to control the flow of wastewater into the first stages of treatment, which are installed after the averager.

After the filters, water is also fed by gravity to the UV irradiation unit, where, in addition to disinfection, part of the difficultly oxidized organic and inorganic substances is oxidized by ozone and oxygen and hydroxyl radicals formed under the action of hard UV radiation on water molecules and dissolved oxygen. In general, the installation has increased cleaning efficiency.

Utility Model Implementation

Wastewater enters the sewage well, and then into the averager. Averaged wastewater through the external sewage network enters the distribution chute 1 (Figure 1.). The distribution chute is equipped with gates to regulate the flow of wastewater into the tank of the first stages of the cleaning chain 2. The lower part of the tank is filled with blocks of the microorganism carrier 3. Due to intensive aeration, favorable conditions are created in the compartment for the development of aerobic cultures of microorganisms with high fixing ability. Accordingly, an attached biocenosis of microorganisms develops on the surface of the carrier. Microorganisms attached to the surface of the carrier adsorb contaminants from the flowing water and oxidize them to carbon dioxide and water. When it enters the tank, the wastewater is mixed for a short time with the entire contents of the compartment, which reduces the likelihood of sludge dying off in the case of volley discharge of heavily contaminated wastewater.

Aeration of the wastewater in the tank is carried out by compressed air supplied through porous fine-bubble aerators 4 from the compressor 5. Next, the drains through the holes in the light partition flow into the tank of the second stage 6.

The capacity of the second foot is arranged similarly to the capacity of the first step. In the second stage tank under conditions of relatively low loads, nitrifying cultures of microorganisms develop, oxidizing ammonium nitrogen to nitride and then to nitrate. Denitrifying microorganisms develop in the depths of the biofilm under conditions of oxygen deficiency; therefore, runoff denitrification partially proceeds in the tank of the second stage. From the tank of the second stage, the drains pass into the denitrifier 7 which is separated from the tank of the second stage by a light partition.

The denitrifier is arranged similarly to the previous tanks, but there is no air supply in the operating mode, due to which anoxic conditions are created in the liquid volume, which are favorable for the vital activity of denitrifying microorganisms. As the silt mixture passes through the carrier blocks by specialized microorganisms, nitrates are reduced to molecular nitrogen. As a result, there is a decrease in the concentration of nitrates in the effluent. Due to the lack of mixing, all suspended particles are intensively fixed on the biofilm covering the loading surface. Periodically (1 time per month), air is supplied to the air distribution system of the denitrifier by opening the valve 18. In this case, sediment is stirred up and, accordingly, the charge is regenerated. Next, the water through the distribution manifold 8 enters the sump 9.

In the sump there is a gravitational separation of the sludge mixture. Sludge suspension is deposited in the bottom of the sump 9, from where airlift 10 is pumped to the first stage, and the excess amount is transported to the sludge platforms by opening the taps 11. The airlift is regulated by the crane 12. The clarified water from the upper part of the sump flows by gravity to the third stage 13, where under intensive aeration is a deep oxidation of organic substances carried out from the previous steps and the saturation of purified water with oxygen.

The capacity of the 3rd stage is equipped with a membrane tertiary treatment unit. A mixture of activated sludge and wastewater is pumped into an external membrane module. Next, the mixture is filtered and discharged. The concentrated mixture is recycled to the tank by a recirculation pump. Excess activated sludge is discharged from the system.

The membranes are equipped with an aeration system. Air is supplied from the blower to the aerators, which are usually mounted in the membrane modules themselves.

The purified water from the tank of the third stage is fed by gravity to the filter 14. The working element of the filter is polystyrene foam 15, located between two shelves. Water, moving from top to bottom, passes through the loading layer, resulting in a deep cleaning. Then, gravity water is fed from the chain filters to the UV-irradiation unit 16. In addition to the main purpose of the UV-irradiation unit, the UV-irradiation unit oxidizes part of the difficultly oxidized organic and inorganic substances with ozone and oxygen and hydroxyl radicals formed under the action of hard UV-radiation on molecules water and dissolved oxygen. The purified and disinfected water is discharged from the installation through pipeline 17.

Description of drawings

Figure 1 shows the technological scheme of the biological wastewater treatment plant, which includes two treatment chains.

Claims (2)

1. Installation of biological wastewater treatment, which includes an averager, a chain of stages of aeration treatment by microorganisms, denitrification by microorganisms, a sump, the third stage of aeration treatment with membrane filtration and airlifts, a polystyrene filter, and also including a UV irradiation unit, characterized in that has at least the same two chains, passing through each of which the wastewater passes one after another two stages of aeration cleaning by microorganisms, in the last of which proceeds nitrification and denitrification partial flow, in a third stage of purification aeration and aeration is increased relative to the other stages, wherein aeration systems are provided as the third stage membrane aeration purification. 2. The biological wastewater treatment plant according to claim 1, characterized in that the devices for distributing wastewater into the chains after the averager are gates.